Dr. Zooch Saturn V Cluster Mod

[Silverfish]

Wow, my first thread!
I recently ordered a Dr Zooch Saturn V, and before it comes through in the post, thought I would start this thread so I can get on and build it as soon as it arrives!

Although it is already a great kit, I would like to make it even more impressive by making it a cluster (this is only my third rocket, and first cluster, so i am a relative novice ). I was originally thinking of doing a 4 18mm cluster, but that would obviously not fit inside the body tube. I then thought that a better option would be to have one central 18mm engine, and then four outer 13.5mm canted ones (if that will even fit, which I doubt it will :s), so I could then fly it on either one, or a cluster of engines.

The problems that I am faced with are as follows:
1) What is the diameter of the body tube, and what arrangement of engines would fit inside it (see attachments for my ideas)?
2) I would like to keep the F1 engines attached during the flight, but do not know if this will be possible (see attachment for my idea).
3) As I do not have the Rocksim file of the Saturn V, I am not sure how much more weight I would need to add to the nose cone for it to be stable.

I am sure that these are only the start of my worries, and that I am going to have a difficult time trying to achieve my goal, but I know there there are some very talented rocketeers on this forum, and any input would be most welcome.

Thanks,
Silverfish

 

[RangerStl]

I'll defer to Dr. Zooch for the real answers, but my opinion is that you're going to have a lot of trouble doing that in that size. I think his kit is BT-60 based which is 1.6" ID or 40.5mm. I also know that hos nose cones are ballasted to work with smallish, scale-looking fins. There really isn't any margin to increase the engine weight by 1.5x and still be stable.

Also, since this is your first cluster and third rocket, I can identify and appreciate your enthusiasm. However, to save getting yourself frustrated trying to do the ultimate project first I suggest you get a clustered sport rocket kit first. This will allow you to see what you are getting into. I'm pretty sure a clustered Zooch Sat-V would reach Low Earth Orbit IF you could add enough nose weight to make it stable.

There are several cluster kits available, the one that always jumps to the front of my mind is the Flis Kits Deuces Wild (BT-60 2x 18mm) because of its cult following around here He also has the Richter Recker (3x24mm :eyepop https://www.fliskits.com/products/01prod_fs.htm

Semroc has a few including a larger scale Sat-IB. https://www.semroc.com/Store/scripts/prodList.asp?idCategory=80

Starlight has the Serion (BT-60 3x18mm).

There really are too many vendors to mention each specifically. I hope others will chime in with their favorite beginner cluster rockets.

And welcome to TRF.

N

 

[Micromeister]

SilverFish:
Clustering is my #2 passion with mod-rocs. As a matter of fact what your planning is exactly what I'm doing with my Zooch Saturn-V.

While pointing the outboard 13mm motors toward the models LOADED CG is a good thing, it's also not completely necessary. In This case I'd suggest moving your 13mm motor mounts inside the main body the BT-5 and BT-20 tubes can actually touch if you like. I alway seperate mine by at least a couple thicknesses of Cardstock so I can externally tape each motor to the motor tube as well as friction fit.

If your planning on using the engine bells you can move the 13mm tubes out to the inside edge of the main body and offcenter set the bells a bit to hide the difference. I haven't gotten to that point yet.

Generally when I'm clustering a proven design model I keep careful track of the mass of all the extra added components and add that and 1/2 of the extra motors mass to start, then adjust as necessary to get the CG back to the original starting point.
Clustering is Great fun but is not just a matter of sticking a few more igniters in the motors. To be clear Clustering is as much an ART as Science. I strongly suggest using only a 12V High amp cap. battery, and a Relay ignition system moving the power supply to the Launcher rather then the controller of the system. Rule of thumb for BP clusters is 2 amps per igniter.
Most important is to Check each igniter for continuity before, and AFTER they have been installed in the motors. I can't tell you how many BAD directly out of the unopened igniters or motor packs if found in recent years. Check, Check, Check
If your really interested in clustering BP motor in our models I invite you to visit the Library section of narhams.org In the Tech-Tips file you can download "Clustering BP motors" Tech-Tip-006 that is loaded with a ton of info on what really as to happen for reliable BP cluster success, gizmos and gadgets to helps, and schematics for a Heavy duty relay system that has provided me with exceptional service for over 30 years.

Good luck with your first cluster. Personally; I'd really suggest getting your feet wet with a couple 2 and 3 motor clusters before jumping into a 5 or greater motor model, but if you really pay close attention to detail and procedure you should be OK. My First cluster was a 4- C6 clustered Saturn-1B back in the stone ages LOL

Edit: Looking at the kit, RangerStl is correct it is BT-60 not BT-70, I'm looking at 5 13mm mounts still thight but they'll go.

 

[Silverfish]

Having done some research on the internet in response to your replies, I came across this dual engine cluster kit, which fits the BT-60: https://www.modelrockets.co.uk/shop/product_info.php?cPath=50_113&products_id=1279

This may be a far easier alternative, as I wouldn't have to add as much extra nose weight, and it would fit directly into the body tube (not to mention save money on buying motors and igniters!! ). I could then use two of the F1's from the kit either side, and make my custom ones over the two motors, or just leave them with an engine hook. It may not be quite as exciting, but as both would be the same class of motor and have the same delay, I would not have to worry about getting the ejection charges to fire at the same time.

Silverfish

 

[Micromeister]

Silverfish:
Having logged litterly 1000's of Clustered flights over my 40Plus years of flying. I can positively guarentee you do not have to worry about multi motors ejecting at the same time. They will not, one of the ways we cluster freaks like to get an early read on how our Cluster models did, we'll count the number of Pop,Pop Pops. we hear at ejection to confirm the number the lit. I can count on one hand the number then ejected so closely that they were counted as a single ejection.

When designing your Cluster models it's fitting to ensure your laundry will be ejection by a single motor in the cluster. Stuffer tubes and other volumn limiting techniques help in these cases

 

[Silverfish]

Going to the topic of launch controllers for a second, I have come across these 'Quick Match' igniters: https://www.modelrockets.co.uk/shop/product_info.php?cPath=28_46&products_id=912

These would prevent me from having to get a larger launch controller, although I do not know how reliable they are (the last thing that I want is for one of the engines not to ignite), or whether it would be better to use a 12V controller and some cluster clips?

P.S. Micromeister, having read the narhams.org cluster article, I WILL build a continuity checker, but building my own relay launcher seems too difficult for someone like me with no real electronics experience. I would love to see some pictures (or do you have a build thread?) of your saturn, to help me decided which combination of motors to use! Thanks

Silverfish

 

[JStarStar]

BT-60 is 1.637" = 41.5 mm, so you could not build a 5-motor cluster of 1 x 18 mm and 4 x 13 mm inside a BT-60, without cutting and canting the tubes as your sketches illustrate.

That can be very tough to do accurately, even for long-experienced builders, and mis-cutting the cant angles by even a mm or two can have major effects on the direction of the thrust and send the finished vehicle in all sorts of weird directions. :y::y:

Now, you could fit 5 13 mm motor tubes all inside a BT-60 - (3 x 13 = 39), so if you were OK with all the motors being 13mm, it would be possible to do it without going through the advanced detail work of canting the tubes.

Heck, if you can obtain MMX motors and parts (10mm tube), THAT might even be a solution -- go with the stock 18mm motor mount for the center, and use MMX motors for the 4 outboards. Using MMX outboards, you might even be able to use the engine bells.

You're not really depending on the outboard motors for serious thrust power -- you're not entering any altitude contests here -- if what you want is to have a Saturn V leave the pad with 5 motors burning, that might be the way to do it.

MMX motors would of course be lighter than even 13mm motors, so that would be somewhat beneficial in the CG situation (less weight in the tail end).

 

[luke strawwalker]

Wow, my first thread!
I recently ordered a Dr Zooch Saturn V, and before it comes through in the post, thought I would start this thread so I can get on and build it as soon as it arrives!

Although it is already a great kit, I would like to make it even more impressive by making it a cluster (this is only my third rocket, and first cluster, so i am a relative novice ). I was originally thinking of doing a 4 18mm cluster, but that would obviously not fit inside the body tube. I then thought that a better option would be to have one central 18mm engine, and then four outer 13.5mm canted ones (if that will even fit, which I doubt it will :s), so I could then fly it on either one, or a cluster of engines.

The problems that I am faced with are as follows:
1) What is the diameter of the body tube, and what arrangement of engines would fit inside it (see attachments for my ideas)?
2) I would like to keep the F1 engines attached during the flight, but do not know if this will be possible (see attachment for my idea).
3) As I do not have the Rocksim file of the Saturn V, I am not sure how much more weight I would need to add to the nose cone for it to be stable.

I am sure that these are only the start of my worries, and that I am going to have a difficult time trying to achieve my goal, but I know there there are some very talented rocketeers on this forum, and any input would be most welcome.

Thanks,
Silverfish

Here's what I know:

1) the kit is based on a BT-60 body tube, 1.637 inches outer diameter (check Semroc's site for the inner diameter, but I think you'll find your limited to a cluster of (5) 13mm mini-engines (dash-T engines) for this size body tube.

2) there is NO room to cant the engines, and NO reason to do so, because if you have one engine not ignite at takeoff, the off-axis thrust is DEFINITELY going to cause problems, making the rocket unstable. You can have enough problems as it is with the off-center thrust from a no-start as it is, with all the engines firing along the same axis-- with canted motors it's virtually certain doom.

3) this idea has been discussed before, and some folks have done it (search for the thread either here on TRF, over at Ye Olde Rocketry Forum, or on Rocketry Planet, I cannot recall at the moment which forum the thread discussing the cluster kitbash was on, but there is a lot of good information there.

4) One big problem you're going to have is, finding a long enough delay. Basically you're talking about launching a rocket with power equivalent to a "C" motor yet only having 2-3 second delay AT MOST, which is really too short for this model. The additional noseweight required will help offset this some, but you really need to model this in Rocksim to avoid nasty surprises...

5) The easy answer to the question of "how much noseweight" is, whatever the difference is in the weight of the new motor mount plus engines compared to the old motor mount with it's engine. Say you construct the kit motor mount per the instructions, install an engine, and it weighs (just a number here) 50 grams. Say you also construct your new clustered motor mount, install all the engines, and weigh it and it weighs in at say 150 grams. You'd have to install 100 grams of noseweight to offset the additional weight in the tail of the rocket, to keep the CG at the exact same point (negating moment-arm effects for the moment and assuming the CG is at the exact center lengthwise of the kit.) If the CG is further aft, less weight would actually be required in this case to move the CG forward, because that weight would be further from the CG (presuming you put it in the forwardmost part of the nose, which is NOT going to be easy with this kit since it has a BT-50 nosecone, already pre-weighted, and the rest of the cone is solid balsa, except for the paper Apollo Capsule through which the LES escape rocket dowel is glued. It would probably be possible to add plenty of weight to the BT-50 upperstage tube (representing the S-IVB stage) but the further back from the nose the weight is, the shorter it's moment arm and therefore the more weight is required to get the same forward shift of the CG. If you want, I could load and weight my Saturn V and locate the CG for you if built "stock" and that would give you reference to work from. That way, you install your cluster motor mount, and just add weight to the BT-50 tube until it balances at the exact same CG point as the unmodified kit.

6)This raises another problem-- as the weight of the rocket increases, so does it's inertial moments... meaning that the fins are less effective at stopping undesired motions of the rocket and take longer to push the rocket back onto the desired course (remember Newton's laws and conservation of momentum-- it's easier to get a lighter object moving than a heavy one, and it's easier to stop a lighter object when you've moved it far enough than it is to stop a heavy one. Your fins are the same size, so the amount of 'work' they can provide (lift when at an angle of attack) is the same, but now they're having to push a much heavier rocket back on course, which will take longer to accomplish. What all this means is the rocket is going to do a LOT of tailwagging and corkscrewing as it flies because it's underdamped, and just kinda 'flail around the sky' so to speak... Larger fins would help with this, but then they'll look funny too, unless you go with clear slip-on fins or add oversize clear fins to the back somehow (this will reduce the need for lots of extra noseweight as well, since extra-size fins will shift the CP rearward, meaning the CG doesn't have to be as far forward to maintain stability as it has to be on the stock kit with the stock fins).

7) You'll have to have a bigger chute to safely return this rocket from apogee, as hopefully that's where it'll eject, because of the additional weight. Rocksim would help here as well as it can calculate chute size for you and you can experiment with different size chutes until you get what you want.

8) It won't be possible to fly the rocket with the F-1 engines on the kit-- they're too small (see my build thread for more info on the Zooch Saturn V kit from a couple weeks ago). If you've clustered to 13 mm engines anyway, you COULD just extend the motor mounts out a bit (sorta like the engine 'spoofs' on the Zooch Atlas-Agena kit I've got a thread going on) and let them 'serve duty' as the F-1's. Don't move the engines too far back or you make problem #5 and 6 worse though... :shock:

9) since your just getting started good in rocketry, and haven't gotten any cluster experience before, I personally would recommend you file this project away for awhile. I know, I've been there too, and it's easy to get 'go fever' and want to jump into an uber-cool sounding project with both feet and realize later that you bit off more than you can chew, or that it just doesn't work, is dangerous, or whatever. If you're really determined to do this, I'd recommend that you get a commercially available clustered kit and build it stock-- it's amazing how much you can learn from each build if you pay attention to what you're doing and WHY you're doing it that way, what the reasoning is and the mechanics behind it, and then you can figure out better ways of doing it later on Seriously, some familiarity with commercial designs will help to know what works and what don't, what to look for, etc. before jumping into a project like this.

10) If ya don't have rocksim, you're really missing out. Rocksim is PERFECT for a project like this because it helps you SO MUCH to see how things fit together before you actually build it, to test things out, see what works and what doesn't, etc. You have to be careful with Rocksim, because as most computer guys will tell you, "junk in-junk out", meaning the simulations and stuff are ONLY AS GOOD AS THE INFORMATION YOU PUT IN-- the more accurate, the better! Actually weigh the components you're contemplating and plug those numbers into the design instead of the 'default' numbers (not that the defaults are all bad or anything, but the more accuracy you have in the component weights, the better the CG calculations will be, the better the sim runs will be, etc.) I'd even recommend that if you go forward with this, that you build a 'boilerplate' version of it from paper towel tubes (they're usually BT-60) and test the idea out using cheap parts before you build the real thing-- that way if it crashes, you're only out the paper towel tube and not a kit...

Good luck and any more questions feel free to ask! OL JR

 

[luke strawwalker]

Going to the topic of launch controllers for a second, I have come across these 'Quick Match' igniters: https://www.modelrockets.co.uk/shop/product_info.php?cPath=28_46&products_id=912

These would prevent me from having to get a larger launch controller, although I do not know how reliable they are (the last thing that I want is for one of the engines not to ignite), or whether it would be better to use a 12V controller and some cluster clips?

P.S. Micromeister, having read the narhams.org cluster article, I WILL build a continuity checker, but building my own relay launcher seems too difficult for someone like me with no real electronics experience. I would love to see some pictures (or do you have a build thread?) of your saturn, to help me decided which combination of motors to use! Thanks

Silverfish

Micromeister makes some VERY good points, but I'd offer a counterpoint. Check out the new Q2G2 ignitors from Quest Aerospace. These are turn-key ready to go ignitors that are PERFECT for clustering! They have a MUCH lower firing currrent requirement than Estes Solar Ignitors and they are constructed MUCH better than the Estes ignitors as well. Estes ignitors are as old-fashioned as folded over bare nichrome ignitors compared to these things...

The Q2G2's consist of a pair of slender insulated wires twisted together, with about 2-3 inches of untwisted length and then ends stripped for connecting the microclips of your launcher. The twisted end is dipped in pyrogen much like the Estes ignitors, but these are then covered by a thin plastic 'straw' about 1/2 an inch long, which protects the pyrogen tip from getting damaged in storage-- no more opening the package to find half the ignitors' tips dinged or the pyrogen flaked off and a little crusty dust falling out of the package into your hand. The longer insulated wire leads mean you don't need clip whips except for LARGE clusters, and the wires can easily be gathered into pairs and the uninsulated wire tips can be twisted together to parallel-wire the cluster for proper ignition. The 120 milliamp firing current of these ignitors (like less than 1/10 the requirement of Estes ignitors, at LEAST) means that even if you have a less than ideal power source or a clip whip with a little more resistance in one connection than the others somewhere, you're FAR more likely to get a good ignition. Yes, relayers are handy, and just about a necessity for large clusters with Estes ignitors, but really is overkill for Q2G2's. I WOULD recommend a good 12V battery (car battery or jumper pack, which is what I use, but anything delivering a good decent amount of current at 9-12 volts should do IE "D" cell batteries instead of AA batteries, or a lantern battery (depending on it's C-rating (current delivery). More voltage helps overcome any resistance in the firing circuit, and plenty of current insures the ignitors heat fast and light together. The lower current requirements of Q2G2's really helps here.

NOTE: These ignitors have SUCH a low firing current that you cannot continuity test them with cheapy Estes style launchers using flashlight bulbs for the continuity test-- the light bulb passes too much current and will fire the ignitor when the key is inserted for the continuity check! Replace your flashlight bulb in your controller with an LED flashlight bulb that passes no more than a few milliamps of current and the regular Estes controller will work with the Q2G2's, or you can install LED indicators from Radio Shack if you really want to make the Estes controllers into a good controller. There are threads around here on this too... Plain LED's can work if you solder a proper-value resistor in series with them and wire the polarity correct, or use red/green forward/reverse polarity LED's. It's really not that hard once you read up on this stuff... Even relayers are that hard once you learn a little about electronic circuits...

Quest also sells a controller that is already compatible with their Q2G2 ignitors and has available external battery clips, so that's a turn-key deal ready to go. Their controller is a little nicer than the Estes one anyway, IMHO.

Later and hope this helps! OL JR

 

[luke strawwalker]

BT-60 is 1.637" = 41.5 mm, so you could not build a 5-motor cluster of 1 x 18 mm and 4 x 13 mm inside a BT-60, without cutting and canting the tubes as your sketches illustrate.

That can be very tough to do accurately, even for long-experienced builders, and mis-cutting the cant angles by even a mm or two can have major effects on the direction of the thrust and send the finished vehicle in all sorts of weird directions. :y::y:

Now, you could fit 5 13 mm motor tubes all inside a BT-60 - (3 x 13 = 39), so if you were OK with all the motors being 13mm, it would be possible to do it without going through the advanced detail work of canting the tubes.

Heck, if you can obtain MMX motors and parts (10mm tube), THAT might even be a solution -- go with the stock 18mm motor mount for the center, and use MMX motors for the 4 outboards. Using MMX outboards, you might even be able to use the engine bells.

You're not really depending on the outboard motors for serious thrust power -- you're not entering any altitude contests here -- if what you want is to have a Saturn V leave the pad with 5 motors burning, that might be the way to do it.

MMX motors would of course be lighter than even 13mm motors, so that would be somewhat beneficial in the CG situation (less weight in the tail end).

That's not a bad idea Star! Wish I'd have thought of it!

That would probably allow some simulated F-1's to be mounted over the micromaxx motor tubes, and I doubt it'd have enough power from the 4 micromaxx engines alone to actually lift the Saturn V off the pad if the central 18 mm engine (which would handle the ejection of the parachute) didn't ignite. That's one problem with clusters, especially big clusters and heavy rockets (lots of noseweight for stability). If one or more of the cluster doesn't light, you can end up seriously underpowered and end up with a lawndart before the ejection charge even thinks about blowing.

You could probably adapt the stock engine mount from the kit to mount four outboard micromaxx motor tubes using the kit's own 'bottom heat shield' as a guide to locating them (since that's what's used in the kit to show where to mount the F-1's). You might have to move them a TOUCH inboard (toward the center engine) for clearance purposes, but it could probably be made to work with at least partial F-1 nozzle bells (maybe using only the lower halves--the upper halves are practically cones with a tiny hole at the apex).

BTW, the Zooch kit DOES NOT use a center F-1-- the kit has an extra F-1 in there for a replacement if one gets crushed or ripped off and lost on landing-- see the build threads. SO, if a person wanted to do a "double 18 mm motor" cluster, you probably could so long as the two center BP motors were clocked straight across or straight up and down as a pair in the center, with the fairings, fins, and outboard F-1's clocked to look like an "X"-- sorta like this if this will work:

F F
OO
F F

Where "F" is the F-1 engines, and the "OO" is the two clustered BP rocket motors. (if the diagram worked)

Anyway, hope this helps... OL JR

PS... ok, it didn't work... the F's should have been seperated by four spaces... Oh well, back to the drawing board!

 

[luke strawwalker]

Ok, the anagram display I tried didn't work, so I took a few minutes, sketched it out, and scanned it in. Hope this helps! OL JR

 

[MarkII]

I hope that the following isn't just a repetition of the same information that Micromeister posted. At 6mm in diameter and 26mm in length, Micromaxx motors fit into small tubes from either FlisKits (BT-2.5), Aerospace Speciality Products (T-MM) or Balsa Machining Service (T2-PLUS). MMX motor tubing has an OD of 0.281" (7.14mm).

The motors themselves only weigh 1 gram apiece, so they would only have a small effect on the location of the CG. The regular Micromaxx II's have a delay of ~0.9-1.0 second, so you wouldn't want to have them vent their ejection charges into the rocket. You can use Micromaxx II-NE's, though, which have no ejection charge, and install plugged motor tubes for them in your rocket.

Micromaxx II's have a burn time of about 0.8 seconds, which is comparable to the burn time of Estes B6's, and a little less than half the burn time of Estes C6's. During the flight, you would briefly be able to see their flames, along with the flame from a central B6 if that is what you will be using. The tiny Micromaxx engines will contribute thrust (about 2 Newtons apiece immediately after ignition), adding 8 Newtons to the B6's peak thrust of 12.14 Newtons, although they will reach their maximum thrust a few milliseconds earlier than when the B6 hits its peak. That can be a good thing, though.

The four Micromaxx II's will add 1.2 Newtons of total impulse to the B6, pushing it just over the line into low C territory, and they will provide some extra smoke, noise and flame at liftoff, all for almost no weight penalty. All in all, it sounds like it could be a worthwhile project if your building skills are up to the task.

MarkII

 

[Dr.Zooch]

Wow, my first thread!
I recently ordered a Dr Zooch Saturn V, and before it comes through in the post, thought I would start this thread so I can get on and build it as soon as it arrives!

Although it is already a great kit, I would like to make it even more impressive by making it a cluster (this is only my third rocket, and first cluster, so i am a relative novice ). I was originally thinking of doing a 4 18mm cluster, but that would obviously not fit inside the body tube. I then thought that a better option would be to have one central 18mm engine, and then four outer 13.5mm canted ones (if that will even fit, which I doubt it will :s), so I could then fly it on either one, or a cluster of engines.

The problems that I am faced with are as follows:
1) What is the diameter of the body tube, and what arrangement of engines would fit inside it (see attachments for my ideas)?
2) I would like to keep the F1 engines attached during the flight, but do not know if this will be possible (see attachment for my idea).
3) As I do not have the Rocksim file of the Saturn V, I am not sure how much more weight I would need to add to the nose cone for it to be stable.

I am sure that these are only the start of my worries, and that I am going to have a difficult time trying to achieve my goal, but I know there there are some very talented rocketeers on this forum, and any input would be most welcome.

Thanks,
Silverfish

First off... you should buy two Saturn V kits... one to do this idea of yours on and one to replace the first one after it turns into smoldering wreckage on the ground. Make sure that everyone stands way- WAY back too. In other words- my advice is don't try this. Considering that this is only your third rocket and that this concept of yours is way, way out of the design envelope of the Dr. Zooch Saturn V kit, you will be comprimising your own safety as well as the safety of persons and property around you.

The Dr. Zooch Saturn V kit has NOT been tested in this configuration and is NOT designed for flight in the manner that you have illustrated in this thread. This rocket has the most narrow margin for stability of any rocket in the Dr. Zooch line. In many cases having the CG aft by as little as 1/4 inch is enough to make the rocket go unstable. Adding weight to the nose leads you into the Inertial Moments thicket that Luke spoke of. It is a no-win situation.

My best advice is that you should get a length of T-60 tube, a balsa adapter and a length of T-50 tube and a nosecone and start from there- make a test bed vehicle to try out your idea on. Rocksim it fly it and then mod it down until you have something you like that works, or doesn't work. PM me your snail mail address and I will send you- FREE some T-60 tube, T-50 tube and the associated balsa adapters to test with- I have a TON of scratch and dent extras here in the factory that I'll be MORE than happy to send you so you can test out your idea- just don't do it on the Saturn V kit. If you were an expert builder such as Luke or Micro et.al. I'd not say a thing and let you go ahead- just so I could get the money for the replacement kit... but for a 3rd time builder... I'll just warn- DON'T!:gavel:

 

[dwmzmm]

I agree with Dr. Zooch. I would just fly his Saturn - V as designed & kitted; I think if modified greatly the burden of keeping things safe will fall on you. When I modified my Estes K-36 Saturn - V to a five engine cluster, I put a LOT of thought into it and spent several years planning on what I was going to do to make the needed changes to insure the model will fly safely. The only glitch I ran across in the actual flight was the recovery of the upper section. With that all important first flight out of the way, I now KNOW what I need to do to make the needed changes and fly this baby again.

 

[MarkII]

On second thought, I have to concur with Dr. Zooch, Dave and the strawwalker. When you are ready, try the idea first on several builds that allow you to have more control over the variables. But do build and fly a bunch of conventional designs first, to build up your "practical experience" and "flight time" accounts. They will prove to be your most valuable resources! Take it from someone who is still trying to "feed the pig" on behalf of his own balance sheet!

MarkII

 

[luke strawwalker]

First off... you should buy two Saturn V kits... one to do this idea of yours on and one to replace the first one after it turns into smoldering wreckage on the ground. Make sure that everyone stands way- WAY back too. In other words- my advice is don't try this. Considering that this is only your third rocket and that this concept of yours is way, way out of the design envelope of the Dr. Zooch Saturn V kit, you will be comprimising your own safety as well as the safety of persons and property around you.

The Dr. Zooch Saturn V kit has NOT been tested in this configuration and is NOT designed for flight in the manner that you have illustrated in this thread. This rocket has the most narrow margin for stability of any rocket in the Dr. Zooch line. In many cases having the CG aft by as little as 1/4 inch is enough to make the rocket go unstable. Adding weight to the nose leads you into the Inertial Moments thicket that Luke spoke of. It is a no-win situation.

My best advice is that you should get a length of T-60 tube, a balsa adapter and a length of T-50 tube and a nosecone and start from there- make a test bed vehicle to try out your idea on. Rocksim it fly it and then mod it down until you have something you like that works, or doesn't work. PM me your snail mail address and I will send you- FREE some T-60 tube, T-50 tube and the associated balsa adapters to test with- I have a TON of scratch and dent extras here in the factory that I'll be MORE than happy to send you so you can test out your idea- just don't do it on the Saturn V kit. If you were an expert builder such as Luke or Micro et.al. I'd not say a thing and let you go ahead- just so I could get the money for the replacement kit... but for a 3rd time builder... I'll just warn- DON'T!:gavel:

Hey, can't ask for more than that! Scratch and dent Zooch stuff... FOR FREE!!! How cool is that??

I thought about this same conversion for my Saturn V but decided I just wanted to build the kit STOCK FIRST, and then later on if I really wanted to I'd spring for another kit (hey, they're cheap enough-- cheaper than a lot of Estes stuff anyway, and DEFINITELY cheaper than a lot of other kits out there!) and mod that one into whatever I wanted. I'm pretty glad that I did, because while this kit is about 18 inches tall or so, on a C6 motor it scoots off the pad pretty darn quick. You don't really have time to 'see the flames' and all that-- it's not a 'slow majestic takeoff' like you get from the more massive kits in 1/100 scale or above; this sucker moves out pretty quick like any other BT-60 kit with a C motor in it! Add four micromaxxes and it's just going to scoot that much faster, or probably about the same speed off the pad as a C motor if you put a B motor in the center tube instead with the micromaxxes. Besides, it flies great, so why mess with a good thing???

I think you'd do better (IMHO) to do a killer finishing job on it and not worry about only 1 flame coming out of the bottom, as you only see that for a second or so anyway-- a killer finish really gets attention on the pad, at the RSO table, and in your prep area, and you can look at it all day on display! Work on the cluster stuff 'for fun' later on with some scratch and dent zoochie stuff like Wes suggests...

Later! OL JR

 

[Micromeister]

10-4 on that! can't argue with free stuff from the Kit manufacturer LOL!!!
Great offer Doc!

I do think you'd be alot better off gaining expenience with a couple 2, 3 and 4 motor clusters before jumping into something that takes a good bit more practice and patience

As luke mentioned Quest Q2G2 Igniters are Excellent for Clustering. Just to get the story staight on these excellent little iginters, They are simply a "New" version of the old MPC igniter for many year back. They are a "designed" 6volt igniter constructed "exactly" the same way as our current estes igniters. Only difference is the lower firing current requirement & tiny glass bead as luke mentioned.
They are Not however without their own set of cautions: Because of the very thin lead wires they tend to short themselvs out easily if your not very careful during installation. they also "tend" to get bent during removal from the packing liner. I have found a number of bad Q2G2's (No continuity) out of the package as well as good old solar igniters.
They can be safely continuity checked with the 1.5v continuity checker you downloaded from Tech-Tip-006. It's fairly easy to retro-fit your Electon Beam or other higher voltage launchers by installing a LED & resistor in place of the 9 or 12volt blub to reduce the continuity current flow.
To be perfectly honest i've been using Q2's in one from or another for several years now when I'm not using my own custom made cluster Igniters. I have a couple hundred of the pre-production bare nichrome bridge, test iginters, and a number of different pyrogen type test runs, i've been using in Micro clusters for a long while now. I really like Q2's and Q2g2 for clustering but that doesn't change the need for a Relay system, decent current output battery and most important Igniter checking before and after installation to ensure success Particularly on Larger number motor clusters.
2 & 3 motor clusters are fairly easy to get everything to go correctly, 4 and above is really where the "Art" part starts to show.

All in All i'm with the rest posting that we really believe it'd be in YOUR best interest to put this particular project on hold for awhile while you build and fly a few lesser motor cluster models, for the FUN and expenience.
Hope this helps.

Edit:
One more thing: When I started out with Mod-Rocs I Knew absolutely nothing about electronics. Building the Relay launcher was one of the very first project I ever did...with only the help gained by the elementry books I picked up at Radio Shack. If you really want to build your own system.. That is EXACTLY what this forum is all about. I and most of the other folks who frequent this particulary forum do so to "Pay Forward" helping others not make some of the silly mistakes we've made in the past if you need help, all ya have to do is ask. Sometimes right here or by contacting off-line.

 

[luke strawwalker]

10-4 on that! can't argue with free stuff from the Kit manufacturer LOL!!!
Great offer Doc!

I do think you'd be alot better off gaining expenience with a couple 2, 3 and 4 motor clusters before jumping into something that takes a good bit more practice and patience

As luke mentioned Quest Q2G2 Igniters are Excellent for Clustering. Just to get the story staight on these excellent little iginters, They are simply a "New" version of the old MPC igniter for many year back. They are a "designed" 6volt igniter constructed "exactly" the same way as our current estes igniters. Only difference is the lower firing current requirement & tiny glass bead as luke mentioned.

(snip).

John, I think you're referring to the older style Quest ignitors that use the glass bead... the new Q2G2's are a pair of twisted insulated multistrand wires with a pyrogen head-- much like a HPR ignitor instead of the typical LPR "Estes-style" Solar ignitor with twin steel wire leads held together (apart?) by a strip of tape (for Estes Solar Ignitors) or the glass bead (older Quest ignitors). Quest used to have those "Tiger Tail" ignitors which were like a corrugated version of an Aerotech "Copperhead" ignitor if memory serves...

AFAIK, Quest is ONLY offering the Q2G2 ignitors anymore, except older motor packs that had the older Q2 "glass bead" quasi-Estes/MPC style ignitors you referred to already packaged in them.

The newer Q2G2's are MUCH more robust than ANY of the solid-wire type ignitors, though the older Q2's with their glass bead looked a lot more robust than the Estes "equivalent" held only by tape that didn't tend to hold them together very well. However, glass bead or no, they were still subject to damage to the unprotected pyrogen head or the leads getting pinched and shorted between the glass bead and pyrogen, or mechanical damage to the bridge wire during fabrication, etc. The newer Q2G2's, having twisted twin leads with the pyrogen (and AFAIK they have conductive pyrogen instead of a bridge wire, but I'm not 100% sure of that) with the pyrogen on the tip using insulated wires, is FAR less likely to have those sorts of shorting or open circuit problems than the older style ignitors. Additionally, the long, flexible, insulated wire 'tails' allow them to reach far enough to be twisted together into pairs and clusters so clip whips aren't necessary except for the largest clusters or very widely spaced inline clusters. This was FAR more difficult with the uninsulated solid-wire older style ignitors.

Have a good one! OL JR

 

[mjennings]

Silverfish welcome to the forum, I'm sure by now you know we have many helpful and knowledgeable folks around here.

I'm gonna agree with RangerSTL, for you to check out a couple of kit clusters first before starting this project. My big project that I've been playing with in my head for years is a shuttle stack that stages.

I'd stick with Dr Zooch's advice the good Doctor won't steer you wrong. Or at least put this idea on the back burner for a while,

I really like JStarStar's 4 micromax outboard idea, but same thing get some micromax experience first.

I like that you think big it makes the hobby fun, and keeps it challenging, but keep in mind the Saturn V wasn't the 3 rocket Von Braun and company designed either. In the long run you'll likely enjoy the build more, and get to fly the clustered Saturn V many times, if you take some smaller steps to get some more experince under your belt.

 

[MarkII]

AFAIK, Quest is ONLY offering the Q2G2 ignitors anymore, except older motor packs that had the older Q2 "glass bead" quasi-Estes/MPC style ignitors you referred to already packaged in them.

As recently as last week, I was still seeing Q2 igniters listed on Quest's website. They are gone from there now, though.

Quest still makes a version of the Q2 "glass bead" style igniters for use with Micromaxx motors. These versions have no pyrogen so that they can fit into the tiny nozzles of those motors. They work great, too!

BTW, is that a "Tiger Tack" igniter plug in the picture of the Q2 igniter that you attached to your post? Wow, I haven't seen one of those in awhile.

MarkII

 

[luke strawwalker]

As recently as last week, I was still seeing Q2 igniters listed on Quest's website. They are gone from there now, though.

Quest still makes a version of the Q2 "glass bead" style igniters for use with Micromaxx motors. These versions have no pyrogen so that they can fit into the tiny nozzles of those motors. They work great, too!

BTW, is that a "Tiger Tack" igniter plug in the picture of the Q2 igniter that you attached to your post? Wow, I haven't seen one of those in awhile.

MarkII

Yep, I think it is... I nabbed those pics off the web after a quick search to prove my point and show the differences... I had a bit of a time finding a pic of a regular old Q2/MPC style ignitor though! Pictures are worth a thousand words, but ya know that doesn't stop me from trying...

When I ordered the bulk pack of Q2G2's when Quest first started offering them, I was double sure to ask Nettie if they were the NEW Q2G2's instead of the older Q2's, and she assured me they were, because they weren't going to be selling the Q2's anymore-- they'd switched production over entirely to Q2G2's. I ordered some motors at the same time and she did tell me that some of the engines I received might have the older ignitors in them, because they were packaged before the switch, but that was it. Maybe they finally sold off all the old inventory, which is why they disappeared from the website only last week?? Just a guess; you'd have to ask Old Rocketeer II (Bill) over on YORF.

I'm not really up to speed with all the micromaxx stuff-- I know a little about them but haven't flown them. I don't see them in the stores much anymore, and I think I'd go blind trying to fly them... I'd heard they had a 'unique' ignitor, but I didn't know it was a Q2 without the pyrogen. Interesting. I guess they'll have to at least keep the machine going to make the wires, bead, and bridge wire for the micromaxxes in that case.

Too bad the old FX motors aren't still around-- or a micromaxx or 13 mm version of them-- that would make a WICKED COOL LOOKING Saturn V takeoff and flight... :dark:

Later! OL JR

PS... whatever happened to "Tiger tails"?? Same problems as Copperheads seem to have so they went away or what?? I know a lot of guys in our club still like copperheads-- they burn them with a cig lighter to seperate the foil ends from the backing and then use regular clips and say they work fine that way...

 

[JStarStar]

Coming back to the thread after a day or so, and seeing the other contributions (especially none other than the Mighty Duke of Zooch himself), I think his advice is probably the soundest.

Saturn V's at every size are a continual headache to keep stable, and most kits are really only marginally stable. (I read somewhere that the real Saturn V was quite unstable, and required continual engine gimballing on launch to keep from doing tail-flips during powered ascent.)

To work around this, almost all SatV models either use a lot of nose weight, or larger-than-scale fins (or some combination of both). Adding weight may produce technical "stability" but as Dr. Z and Luke both noted, then you run into the problem of inertial instability -- once the body starts rotating, there isn't enough correctional force on the fins to stop it.

Installing 4 more motor mounts (either 13mm or 18mm) along with the necessary ducting to deal with ejection charges, is going to add a LOT of weight to the tail end of the vehicle (plus complexity in construction and chances for disaster). Then you add more nose weight to pull the CG forward, and the inertial moment situation gets even worse.

Now, my idea of using MMX motors -- very small in weight -- in the outboard bells might not be quite as bad in that situation, especially if you are using plugged MMX-NE motors with no ejection charge, obviating the worry about containing/diverting the ejection charges.

But even if the MMX motors are not very heavy, if you add 4 motors, along with 4 tubes and glue and even very small mounting structures, you're going to be adding significant weight to the tail. (Although nowhere near as much as 13mm or 18mm motors).

Then on top of all that, there are problems with igniting MMX and conventional BP motors (the core B6-4) simultaneously. As the igniter discussion above gets into, you can't just hook up 5 igniters and push the button. The MMX motors and your inboard B6-4 are not likely to all light at the same time, which will cause all sorts of additional problems. :y::y:

I think as a couple of other posters suggested, I'd think about just building the kit by the book, and do a real knock-dead job on the finish job, make it look really good, like a near museum piece.

Then, if you've still got the real itch to build a canted cluster bird, pick up a FlisKits Deuces Wild or the Tres, which are real crowd pleasers at any launch. You could give them a "Saturn" finish, with black vertical stripes and USA decals, and call it the "Saturn Deuce."

 

[Micromeister]

John, I think you're referring to the older style Quest ignitors that use the glass bead... the new Q2G2's are a pair of twisted insulated multistrand wires with a pyrogen head-- much like a HPR ignitor instead of the typical LPR "Estes-style" Solar ignitor with twin steel wire leads held together (apart?) by a strip of tape (for Estes Solar Ignitors) or the glass bead (older Quest ignitors). Quest used to have those "Tiger Tail" ignitors which were like a corrugated version of an Aerotech "Copperhead" ignitor if memory serves...

AFAIK, Quest is ONLY offering the Q2G2 ignitors anymore, except older motor packs that had the older Q2 "glass bead" quasi-Estes/MPC style ignitors you referred to already packaged in them.

The newer Q2G2's are MUCH more robust than ANY of the solid-wire type ignitors, though the older Q2's with their glass bead looked a lot more robust than the Estes "equivalent" held only by tape that didn't tend to hold them together very well. However, glass bead or no, they were still subject to damage to the unprotected pyrogen head or the leads getting pinched and shorted between the glass bead and pyrogen, or mechanical damage to the bridge wire during fabrication, etc. The newer Q2G2's, having twisted twin leads with the pyrogen (and AFAIK they have conductive pyrogen instead of a bridge wire, but I'm not 100% sure of that) with the pyrogen on the tip using insulated wires, is FAR less likely to have those sorts of shorting or open circuit problems than the older style ignitors. Additionally, the long, flexible, insulated wire 'tails' allow them to reach far enough to be twisted together into pairs and clusters so clip whips aren't necessary except for the largest clusters or very widely spaced inline clusters. This was FAR more difficult with the uninsulated solid-wire older style ignitors.

Have a good one! OL JR

Ooops!! Your right JR; I was looking at the micro Q2G2's Doh! had to go open another pack of the Q2G2's to check the twisted wire pairs. Funny thing is now I'm not seeing the pyrogen tipped micro Q2g2's on Quest's website either, only the bare nichrome type. When the clubs changed over all the system controllers making them continuity safe for all these Low current igniters, all three type Q2 & Q2G2's were amoung those types tested.
I haven't taken one of these twisted wire igniters apart yet to check the construction. They may very well be conductive primer or have a twisted in bridgewire? They are a very nice addition to the igniter aray available to us in any event.

To be honest, I've never had much trouble twisting the old estes igniters into pairs for use in clusters up to 12, for use with a relay system in most configurations, the diagram below and new Q2g2's should make it even easier.
I'll have to use a few more in clusters before I can say much about the plastic straw retainers.... I don't recommend Estes plugs for clusters so we'll have to fly a few to test their holding power before sigining on with this retainer type.

 

[luke strawwalker]

Ooops!! Your right JR; I was looking at the micro Q2G2's Doh! had to go open another pack of the Q2G2's to check the twisted wire pairs. Funny thing is now I'm not seeing the pyrogen tipped micro Q2g2's on Quest's website either, only the bare nichrome type. When the clubs changed over all the system controllers making them continuity safe for all these Low current igniters, all three type Q2 & Q2G2's were amoung those types tested.
I haven't taken one of these twisted wire igniters apart yet to check the construction. They may very well be conductive primer or have a twisted in bridgewire? They are a very nice addition to the igniter aray available to us in any event.

To be honest, I've never had much trouble twisting the old estes igniters into pairs for use in clusters up to 12, for use with a relay system in most configurations, the diagram below and new Q2g2's should make it even easier.
I'll have to use a few more in clusters before I can say much about the plastic straw retainers.... I don't recommend Estes plugs for clusters so we'll have to fly a few to test their holding power before sigining on with this retainer type.

The straw retainers are a pretty good idea... they don't exert as much pressure on the pyrogen as they're inserted in the nozzle, so are less likely to crush the pyrogen or shear off the bridge wire. The straw simply deforms or kinks in on one side to hold the pyrogen in against the grain. Downside is they don't hold with as much force as the plastic plugs.

Of course if I don't have the plugs available (I have a BUNCH of 20 year old motors and even picking up plugs off the ground at the club launches I still don't have enough) I usually just use a ball of wadding installed with a pen and a spot of tape over that. Works well.

I don't know what they're going to do with micromaxx-- never flown them and they aren't readily available around here anymore (WM, LHS, HL) I DO know they had a 'unique' ignitor but other than that, I figured I'd go blind trying to fly MM...

Later! OL JR

 

[Micromeister]

The straw retainers are a pretty good idea... they don't exert as much pressure on the pyrogen as they're inserted in the nozzle, so are less likely to crush the pyrogen or shear off the bridge wire. The straw simply deforms or kinks in on one side to hold the pyrogen in against the grain. Downside is they don't hold with as much force as the plastic plugs.

Of course if I don't have the plugs available (I have a BUNCH of 20 year old motors and even picking up plugs off the ground at the club launches I still don't have enough) I usually just use a ball of wadding installed with a pen and a spot of tape over that. Works well.

I don't know what they're going to do with micromaxx-- never flown them and they aren't readily available around here anymore (WM, LHS, HL) I DO know they had a 'unique' ignitor but other than that, I figured I'd go blind trying to fly MM...

Later! OL JR

The fact that they don't hold as well is exactly my concern when they are used in Cluster applications. Once the igniter is bottomed in the motor core a bit of crushing of the pyrogen isn't a problem. First motion of the model can be quite a kick in the pants, and some of the slower to ignite motors may spit the igniter before it can do it's work if they are not seated securely. This is one of the reasons I don't suggest the use of Estes motor plugs either. Plugs and straws may be OK for 2 and 3 motor applications but I'll stick with the old wadding ball and tape method for bigger motor clusters. I want the igniter to be able to lift the microclip loop if necessary giving the motor at least the 10th of a second to come up to temp.

Actually Luke:
Micro Motors are now packed with bare nichrome Q2G2's. I was hoping Bill would keep the pyrogen tipped around awhile longer as they sometimes come in handy for micro clusteres over 6 or so. I've had pretty good luck with 6 & 8 motor micro clusters with the Bare Q2g2's but I "feel" better with heavy micros using pyrogen tipped. easy enough to do yourself but it was convenient to have them factory made.

Nah! you won't go blind and they are a trip to build and fly. Sometimes a bit tougher to finish but i've been having a ball with them the last several years. Now that we also have sort-of a micro booster in the MMX-II-NE Staged and other types of clusted Micros aren't far behind. but back to the topic......

 

[MarkII]

At the risk of prolonging this OT subject for just a minute more, I wasn't aware that Quest had ever made pyrogen-tipped igniters for Micromaxx. I have also never heard of Micromaxx-specific Q2G2's. I am only aware of two types of igniters that Quest ever made for their Micromaxx motors: the original plug-in QMX igniters (now OOP) and the pyrogen-free Micromaxx Q2 igniters. The latter are similar to Quest's Q2 igniters (now also OOP) for their A-C motors, but without the pyrogen. I have not seen anything about a version of the insulated lead Chinese-made Q2G2's for Micromaxx. As for the QMX igniters, they did not have any pyrogen, either. I don't know how you could fit any kind of pyrogen-coated bridge wire into the Micromaxx nozzle, anyway. It certainly doesn't appear to be necessary; the uncoated bridge wire lights them up just fine.

luke_strawwalker: No, you won't find Micromaxx anything in big box stores like Walmart; I have never seen them carried there. Toy 'R Us used to carry them when they first came out in 1999, but the days when TRU carried anything that required a child to move anything more than his or her thumbs are long gone. I don't know if hobby shops carry them; I have hardly ever seen Quest products being sold in a hobby shop, but I haven't been to very many. You can get Micromaxx motors and kits from FlisKits, Aerospace Specialty Products, Leading Edge, Art Applewhite, QCR and UMRS, to name just a few. All but the latter (FlisKits, ASP, LE, Art and QCR) make their own lines of real kits, ones that you build, for Micromaxx, as well as parts like body tubes, motor mounts, transitions and nose cones. In fact, FlisKits' mid-powered US TOG kit is actually an upscale (that's the US part) of one of Jim's Micromaxx kits. Quest is also now selling parts for scratch-building micro rockets. I feel that the future of the line is bright and getting brighter. This year's NARAM includes a 1/8A (that's Micromaxx) helicopter duration event. It's a bit of a challenge sometimes to build real working rockets on the micro level, especially for competition. There are some really ingenious designs out there. I fly mine for sport, and have a ball doing so. If you haven't checked out Micromaxx lately, then you don't know what you are missing.

MarkII

 

[Micromeister]

At the risk of prolonging this OT subject for just a minute more, I wasn't aware that Quest had ever made pyrogen-tipped igniters for Micromaxx. I have also never heard of Micromaxx-specific Q2G2's. I am only aware of two types of igniters that Quest ever made for their Micromaxx motors: the original plug-in QMX igniters (now OOP) and the pyrogen-free Micromaxx Q2 igniters. The latter are similar to Quest's Q2 igniters (now also OOP) for their A-C motors, but without the pyrogen. I have not seen anything about a version of the insulated lead Chinese-made Q2G2's for Micromaxx. As for the QMX igniters, they did not have any pyrogen, either. I don't know how you could fit any kind of pyrogen-coated bridge wire into the Micromaxx nozzle, anyway. It certainly doesn't appear to be necessary; the uncoated bridge wire lights them up just fine.

luke_strawwalker: No, you won't find Micromaxx anything in big box stores like Walmart; I have never seen them carried there. Toy 'R Us used to carry them when they first came out in 1999, but the days when TRU carried anything that required a child to move anything more than his or her thumbs are long gone. I don't know if hobby shops carry them; I have hardly ever seen Quest products being sold in a hobby shop, but I haven't been to very many. You can get Micromaxx motors and kits from FlisKits, Aerospace Specialty Products, Leading Edge, Art Applewhite, QCR and UMRS, to name just a few. All but the latter (FlisKits, ASP, LE, Art and QCR) make their own lines of real kits, ones that you build, for Micromaxx, as well as parts like body tubes, motor mounts, transitions and nose cones. In fact, FlisKits' mid-powered US TOG kit is actually an upscale (that's the US part) of one of Jim's Micromaxx kits. Quest is also now selling parts for scratch-building micro rockets. I feel that the future of the line is bright and getting brighter. This year's NARAM includes a 1/8A (that's Micromaxx) helicopter duration event. It's a bit of a challenge sometimes to build real working rockets on the micro level, especially for competition. There are some really ingenious designs out there. I fly mine for sport, and have a ball doing so. If you haven't checked out Micromaxx lately, then you don't know what you are missing.

MarkII

Mark:
Sorry, I think I used an improper designations for the Quest igniters.... Q2's pyrogen tipped are what I was referring to. Exactly the same SIZE igniter as are currently being packaged with all micro motors without pyrogen. The Q2's are also IDENTICAL to the OLD MRC or is it MPC?? pyrogen tipped igniters and the same as the igniters packaged with the old FX smoke generators. See pic below.
I believe I mentioned in my previous post I didn't see these igniters offered anymore but had "Hoped" Quest would keep them around for awhile as they were prefect for the larger Micro motor clusters.
What's the largest number of micro motors you've clustered? In larger clusters, 6 and above they are a helps insuring all motors light. Sure the bare wires Q2's work fine for single motors and small cluster use, but to ensure complete ignitions on larger clusters adding pyrogen is a plus.
For your information the pyrogen tipped Q2's as well as Many Estes solar igniters for that matter "fit" just fine in Micro-Maxx-II motors. If we're a little more selective with the pyrogen coverage, they also work very well in MMX-1's. As a matter of fact the igniters used in my first successful 8 motor micro Cluster were pyrogen typed Q2's in MMX-1's motors. This was done because the previous 8- MMX-1 motor flight attempt with bare bridge wire igniters only lite 7 of the 8. I don't understand how you could make such a statement unless you haven't really looked at the possibility or actually tried the fit. I do agree for most applications pyrogen is not needed, but with larger number of motors, it's again that first motion thing. Not all BP comes up to tempature as quickly as others. that little bit of extra heat, or that extra slit second of contact can make all the difference between all motors thrusting and only some.


Mark is right on about the vastly expanding scope of Micro Modeling:
Virtually everything being done or flown in Sport Rocketry is or can be done in micro size, with the possible exception of mile high flights.
We have models in every single type and style. Sport, Scale, PMC, Odd-Rocs, Glider, Flex-Wing Glider, Helicopter, Futuristic, Payload, Staged, Clustered, and more.
We now have on board electronics as well including, staging timers, altimeter, LED Night illumiantion systems, even micro RC...though i'm still having a little trouble with the magnetic servo placement on my micro RCRG
Flight times are shorter on some of the "bigger" models but you'd be amazed at some of the duration flight National Records. PD at 255sec, SD st 78sec, HD (Currently at 64sec) though 111sec flights have been timed just not returned. Flex wing gliders 126sec. Altitude and Cluster Altitude(2 motor) both 82m (269ft).
All the while these models can get you back to actually flying in or from your Backyard or small park, spending less the a buck a flight with models that can also cost less then a buck (Manufactured Kits are considerably more but still quite a bargin compared to even standard size models.)
If your looking for a building challange; there are plenty building in Micro size.

 

[Silverfish]

Hi all,
Thanks for all your feedback, I never thought that there would be so much of it!! I have been at a rocketry workshop over the past few days - you'll be pleased to know that my team's rocket won the 'overall best' prize!! ...... designed by yours-truly ... with some of the credit (but none of the prize) going to you guys - so I haven't been able to check or post on the thread. I think that I have decided to build the Dr Z Sat V as it was originally intended to be built, and then scratch build a cluster (I was thinking of a scaled down Nike Hercules). Maybe then I can build a clustered Saturn V (I was thinking it would be easier to cluster a slightly larger one, 1:1 sounds the right sort of challenge ). A big thanks to the Doc for the offer of bits, (PM on its way) but as I live in the UK this may be less viable ... although the offer is very much appreciated.
Again, thanks for all you feedback, and it's great to have so much back-up.
Silverfish

 

[MarkII]

What's the largest number of micro motors you've clustered? In larger clusters, 6 and above they are a helps insuring all motors light. Sure the bare wires Q2's work fine for single motors and small cluster use, but to ensure complete ignitions on larger clusters adding pyrogen is a plus.
For your information the pyrogen tipped Q2's as well as Many Estes solar igniters for that matter "fit" just fine in Micro-Maxx-II motors.

Well, you've got me there. The largest Micromaxx cluster that I have lit is 3 motors. But I have only used the old QMX igniters for that so far, after removing the igniters from their plug housings, holding them in place with toothpicks (I know, I know... you don't like that method) and firing them with a clip whip. Boy, shoehorning in three sets of microclips under that cluster was fun! But I have had complete ignition of all three motors every time. I have some of the new Micromaxx Q2 igniters (I believe that is what Quest is calling them) but I haven't tried to fire any clusters with them yet. I haven't built any larger MMX clusters because I feel that any more than four is a waste, since at that point you could just use a 1/2A or an A. But I can see doing it with something like a micro version of Boris Katan's TOGinator, where there are motor clusters located in various places on the rocket, though (or even in something a bit more modest than that rocket). Hmmm, a micro TOGinator... wouldn't that be cool?

I was not aware that pyrogen-tipped igniters would work with them. I figured that it was already a tight squeeze when I just inserted the bare bridgewire types, so I assumed that any coating in the wire would make them too thick.

A three motor cluster is also the largest that I have ever fired so far for motors of any size (3xD12's, and I'm 1 for 2 with them). I have a scratch-built 7x18mm cluster under construction, though, and I have a home-buit 7-lead clip whip all ready made for it. (I make all of my own clip whips.)

Mark is right on about the vastly expanding scope of Micro Modeling:
Virtually everything being done or flown in Sport Rocketry is or can be done in micro size, with the possible exception of mile high flights.

I'm sure that someone is working on that, too, now that we have Micromaxx booster motors. Now THAT would need a BIG cluster of 1/8A's to get going... :jaw:

We have models in every single type and style. Sport, Scale, PMC, Odd-Rocs, Glider, Flex-Wing Glider, Helicopter, Futuristic, Payload, Staged, Clustered, and more.
We now have on board electronics as well including, staging timers, altimeter, LED Night illumiantion systems, even micro RC...though i'm still having a little trouble with the magnetic servo placement on my micro RCRG

Really? I would have thought that you had that all debugged and working by now. Along with the micro-sized receiver...

If your looking for a building challange; there are plenty building in Micro size.

John, has anyone built a micro Space Shuttle yet? With parallel-staged boosters and a working glider? Have you?

(Folks, you ain't seen nothing yet until you have seen his working micro Orbital Transport and his working micro Sky Dart.)

MarkII

 

[MarkII]

Sorry, gang -- you see what happens when you get John and me together on the same thread and talking about Micromaxx?

MarkII