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blackjack2564

Crazy Jim's Gone Banana's
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Thought I would start a new thread, other one's getting kinda long.

Had some time on my hands, and got a coat first color of finish on my Tiny Triskileon , along with finishing my first scratch built micro. A copy of my Competitor 4. Yeah I know it's just a NC and 3 fins, but I did not want to get to complicated first time out on scratch a built.

Notice anything missing? Motor mount! With the new booster engines, I want to make this a 2 stage. It's the T-4 tube size.

So I thought I would get some input from the experts on how far to recess the mount and build the booster. As well as should the motor from sustainer extend tight to booster motor, or use a coupler and leave some space between the motors and add some vents.

By the way notice how thin the fin stock is on the 2nd pic edge view, more on that in a minute.

I see others have asked the same, so you guys that have done it successfully shed some light on it for us rookies

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I found this great finstock at Micheal's. I bought a pack of scrap wood , 5 layer Baltic birch, 4 x 6 in. 12 pieces, for making altimeter sleds in my high power rockets.

You know the ones hanging above the large sheets of balsa and birch. Of course they never have the same thing twice in these bargain packs.

When I opened it up there were also 6 sheets same size of very thin veneer. Extremely light and strong, so I made my fins out of it. Seems to be the same thickness as recipe card stock or file folders. But man is it strong, light as balsa, and flexible. Another benefit, you can cut it with scissors ! The corners are missing because now they are my fins! I tries using my exacto, but it was so tough after several passes, hadn't even put a dent in it. Then the light bulb came on. " Try your scissors" bingo, like cutting file folders!

Just for a test I bent it almost completely back on itself, before it broke. As far as it bent, in the pic, it straightened right back out in the 3rd photo.
You don't have to worry about grain orientation either. Just figured I'd pass it on for other scratch builders.

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I found this great finstock at Micheal's. I bought a pack of scrap wood , 5 layer Baltic birch, 4 x 6 in. 12 pieces, for making altimeter sleds in my high power rockets.

You know the ones hanging above the large sheets of balsa and birch. Of course they never have the same thing twice in these bargain packs.

When I opened it up there were also 6 sheets same size of very thin veneer. Extremely light and strong, so I made my fins out of it. Seems to be the same thickness as recipe card stock or file folders. But man is it strong, light as balsa, and flexible. Another benefit, you can cut it with scissors ! The corners are missing because now they are my fins! I tries using my exacto, but it was so tough after several passes, hadn't even put a dent in it. Then the light bulb came on. " Try your scissors" bingo, like cutting file folders!

Just for a test I bent it almost completely back on itself, before it broke. As far as it bent, in the pic, it straightened right back out in the 3rd photo.
You don't have to worry about grain orientation either. Just figured I'd pass it on for other scratch builders.

Jim,

That's aircraft grade 1/64" plywood, buy the looks of it. We carry that in 3" X 6" sheets in our parts department (FSP-1-3-6 3 sheets for $2.75)

Great stuff. I've made 15" diameter body tubes for an upscale mars lander with that stuff :)
 
I use 1/64" ply quite a bit for fin stock, either by itself for micros, or as a laminate on top of other woods (useful for getting fins to the right scale thickness for scale models). You can also laminate it onto foam core board to make lightweight but strong fins for MPR builds.

The two micro gliders shown in the attached photos were made (primarily) out of 1/64" plywood.

MarkII

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Jim:
Along with .005", .010", .015" and .020" G10 and Waferglass, I also use both 3 and 5ply 1/64" and 3/64" lite birch ply for fins and some transitions. All of these items and many others make for some very light exceedingly thin fin materials.
If you'll join the MicroMaxRockets Yahoo group, and pruse the files section of the group, you'll find lists of these and many other materials & product used in the production of micro models.
The joys of these products and others your currently discovering we've been using for awhile now. As Jim mentioned he's got an extensive line of micro parts and related products you should really checkout. Sure makes finding things a lot easier;)

As for advise on Stagings, your gonna have to read a little in some of the other threads or again come and join us in the MicroMaxRockets group, if your looking for more detailed direction. We've been doing these and lots of other micro related things for almost 10 years now.
 
I forgot to mention that two of FlisKit's competition kits, the Cougar 440 and Cougar 660, use 1/64" plywood for fin stock. The instructions call for you to sand airfoils into them! :eek: (And you can - I did! :D )

MarkII
 
I did a few weeks ago. The format is just still a little new to me, making things a tad hard to find. I saw a post about Jim's tiddlywink, but never could find the picture that was supposed to be with it. However I did stumble across the dozens of plans you posted there, and downloaded several.

A few more weeks and hours well spent, and I'll get the hang of the group. I was also trying to stir up some more interest on this forum, hopefully exposing more high power guys into the fun.

Guess I'm in the early stages of the "bug" and wanted the quick route. Time to slow down a bit.
 
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I did a few weeks ago. The format is just still a little new to me, making things a tad hard to find. I saw a post about Jim's tiddlywink, but never could find the picture that was supposed to be with it. However I did stumble across the dozens of plans you posted there, and downloaded several.

A few more weeks and hours well spent, and I'll get the hang of the group. I was also trying to stir up some more interest on this forum, hopefully exposing more high power guys into the fun.

Guess I'm in the early stages of the "bug" and wanted the quick route. Time to slow down a bit.


LOL! I hear Ya Jim!
I don't think we can go too quickly, but sometimes I get teh feeling i'm spending more time typing then designing or building;)

A couple quick notes to help you navigate the group.
After you've logged in on the yahoo group go to the menu of the left side of the screen. Click on any of the areas of interest. You'll find most of the written info in the "Files section" where my micro plans are located. Check out the FAQ file. it's OLD info but it has alot of very useful info there.

Photos are in the Photos section, Many of the members have albums set up so all other memeber can view and download these pics.

Hope this helps a little.
 
I forgot to mention that two of FlisKit's competition kits, the Cougar 440 and Cougar 660, use 1/64" plywood for fin stock. The instructions call for you to sand airfoils into them! :eek: (And you can - I did! :D )

MarkII

I love sanding airfoils in that 1/64" ply. The different layers let you easily see your progress as you sand :)
 
Speaking of staging Micros using the newly certified MMX-II-NE motors.

when we get them from Quest they look exactly like standard MMX-II motors.

Heres what I did with my Booster stash. it's quick, easy and only took about 2 hours to do 24 6pks, making them Instantly recognizable as booster motors in my range and ready motors boxes.
Hope it helps
 
I use 1/64" ply quite a bit for fin stock, either by itself for micros, or as a laminate on top of other woods (useful for getting fins to the right scale thickness for scale models). You can also laminate it onto foam core board to make lightweight but strong fins for MPR builds.

The two micro gliders shown in the attached photos were made (primarily) out of 1/64" plywood.

MarkII

is the one on the right a down scale of a Jet freak?

if it is, how did it perform? and do you have plans?
 
I love sanding airfoils in that 1/64" ply. The different layers let you easily see your progress as you sand :)
Yes, that's what makes it possible! I didn't think I could do it, but it turned out to be not all that hard.

MarkII
 
is the one on the right a down scale of a Jet freak?

if it is, how did it perform? and do you have plans?
Yes it is; you know your gliders! I did these a couple of years ago. I just downscaled the plans (found here), using as the scale factor the difference in the diameter of a BT-20 (the original Jet Freak's motor tube) and the diameter of a BT-2.5. The scale factor is 0.38179347826086956521739130434783 ( ;) ), meaning that the micro version is about 38% of the size of the original plan. I turned the nose cone out of a piece of square basswood stock (the only nose cone that I have ever turned so far).

How did it fly? Well, the nose cone shoulder is actually a short section of BT-2. To provide nose weight, I took a stack of either #2 or #4 steel washers (I can't remember which anymore) and glued it into the shoulder with CA. I arrived at the number by stuffing some washers in and holding them in place with a small ball of tissue, and then giving the glider hand tosses in my living room. Of the three micro gliders that I built, the JF was the easiest to trim balance. I did find that it also needed a little tail weight in the rudder; I used one strip of "match solder" (from Radio Shack) that I folded around the bottom corner of the rudder. (Before permanently attaching it with CA, I had it taped on with a little strip of cellophane tape for trim testing.) On the top of the wings, running down the center, is a narrow strip of 0.005" steel shim stock cut from a sheet that I obtained from Small Parts, Inc.

The Micro Jet Freak had nice long, stable glides in many, many hand tosses in my living room. It has made one actual flight, in which it looped off the pad and right into the ground. I think that I may have made a construction error by giving the motor tube a slight up angle; it probably should either be dead level or else have a slight down angle. But I'll also try more test flights with this build.

Anyway, here are the materials and measurements:

Motor tube: 1" (25.5mm) length of FlisKits BT-2.5
Wings: 2-5/16" (59mm)-root edge; 2-17/32" (64mm)-leading edge; 1-3/16" (30mm)-trailing edge. Cut 2 wings from 1/64" (0.4mm) aircraft plywood.
Rudder: 1-3/32" (27.5mm)-root edge; 1-11/32" (34mm)-leading edge; 7/16" (11mm)-top trailing edge; 1/2" (12.5mm)-trailing edge. Cut from 1/64" (0.4mm) aircraft plywood.
Pylon: 1" x 1/8" (25.5mm x 3mm) parallelogram. Cut from 1/16" (1.6mm) basswood.
Nose cone: 3/8" (9.5mm) long by 0.281" (7mm) diameter rounded ogive, turned down from a short length of 3/16" square (5mm²) basswood.
Nose cone shoulder: 5/16" (8mm) length of FlisKits BT-2, glued to the base of the nose cone.
Jet deflector-wing protector: 1-1/4" x 1/2" (32mm x 12.5mm) strip (and then creased in half lengthwise) of 0.005" (0.127mm) thick steel shim stock.
Launch lug: 1/2" (12.5mm) long FlisKits micro launch lug.

Empty weight: Barely perceptible. :D Seriously, I don't have a scale sensitive enough to measure the weight; on my gram scale, it barely jiggles the needle.

I am planning to build a BT-3 based version (51% scale) of the plan as well. The fantastically high thrust (relative to its size) of the Micromaxx-II motor might have also contributed to the loop. In that case, a larger, slightly heavier version might boost a little more slowly, which might help the JF stay in the air until motor burn-out.

By the way, this glider was designed to eject its motor, but considering the fact that the empty Micromaxx case is so light, I wonder if it really makes any difference if it keeps the motor. I may try it on a Micromaxx-II NE when I get some.

(The other micro glider, my Micro Invader, also looped into the ground off the pad, but this is a notorious problem with that glider's design. Like the full-sized version, it was a bear to trim balance, too. Not shown in the pictures that I posted is my third micro glider, my Micro AMROCS Wombat, which I constructed out of 1/32" basswood. It was built at the same time as the other two. The Micro Invader and the Micro Wombat both use FlisKits nose cones. The Wombat was the only one of the three that did not loop into the ground when it was launched; it actually transitioned into a flat glide. Unfortunately, I had set up the pad too close to my house, and the Wombat sailed right into the branches of a bush immediately after it began its glide. The full-sized Wombat also happens to be the only glider that I have built so far that actually boosts and glides, so it must be a very forgiving design. ;) )

MarkII
 
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Speaking of staging Micros using the newly certified MMX-II-NE motors.

when we get them from Quest they look exactly like standard MMX-II motors.

Heres what I did with my Booster stash. it's quick, easy and only took about 2 hours to do 24 6pks, making them Instantly recognizable as booster motors in my range and ready motors boxes.
Hope it helps

John,

I've heard you refer to these as "booster motors" several times. It sounds great but I wanted to ask if you have tried these, do they work and does Quest bill them as "booster motors"?

As near as I can tell they are motors with a delay but no ejection making it much different than what is defined as a "booster". Also, I haven't heard of any reports about how well these function as boosters. Just want to make sure that if we're going to call them booster motors that that is what they really are...

thanx :)
 
I think that they are simply capped motors with no delay, and you can scrape the clay cap out to modify it as a booster.
 
I think that they are simply capped motors with no delay, and you can scrape the clay cap out to modify it as a booster.

Nope, its the other way 'round. No cap, normal delay (about a half second) and no ejection charge. Micro has flown these as if they were boosters with a 0.5s coast phase between stages. I can see that how you advertise these might be challenging Jim.

"Booster"?
Booster***?
Delayed booster?
Booster with delay?
Coasting booster?
MMX w/o ejection (suitable for some booster applications)?
?????
 
Nope, its the other way 'round. No cap, normal delay (about a half second) and no ejection charge. Micro has flown these as if they were boosters with a 0.5s coast phase between stages. I can see that how you advertise these might be challenging Jim.

"Booster"?
Booster***?
Delayed booster?
Booster with delay?
Coasting booster?
MMX w/o ejection (suitable for some booster applications)?
?????

Well, if/when I carry them I can't offer them as "boosters" unless that is a recommended manufacturers use of the motors, so I will be discussing this with Bill when I place my next order.

I'm not real concerned, but I would like to know if there is any real data out there.

I have seen where regular MMX motors have had the clay cap and ejection charge removed and have been used successfully as boosters, but I don't have any hard numbers. Also, I am not sure if the method that was used to modify the motors may have had an impact on the delay charge (knocked grains loose that can aid in sustainer ignition, for example) so I don't know if these motors manufactured without an ejection charge will act the same way.

I would certainly love to get some data so I am going to order some for development purposes. The possibilities are enticing :D :D

jim
 
I have seen where regular MMX motors have had the clay cap and ejection charge removed and have been used successfully as boosters, but I don't have any hard numbers. Also, I am not sure if the method that was used to modify the motors may have had an impact on the delay charge (knocked grains loose that can aid in sustainer ignition, for example) so I don't know if these motors manufactured without an ejection charge will act the same way.

I would certainly love to get some data so I am going to order some for development purposes. The possibilities are enticing :D :D

jim

My understanding is that this is exactly what these are - the only difference is that Quest is removing the cap and ejection charge at their location and selling them that way. This makes them legal as far as the NAR is concerned (as long as the manufacturer is doing the alterations, that's OK).

You GOTTA do a 2 stage rocket kit for MMX! :p
 
Oh, there's not cap? Huh. Well I've used the normal MMX II motors as boosters successfully, but then the delay has been killing me. On many of the flights, the rockets slowed down too much for a vertical second stage flight.
 
My understanding is that this is exactly what these are - the only difference is that Quest is removing the cap and ejection charge at their location and selling them that way. This makes them legal as far as the NAR is concerned (as long as the manufacturer is doing the alterations, that's OK).

You GOTTA do a 2 stage rocket kit for MMX! :p
Is Quest modifying their stock motors post-production, or are these a special line of motors that are manufactured without ejection charges?

Josh: you would have to build the two-stager to be very lightweight (with a small frontal area), because the booster motor has no more power than the regular Micromaxx-II's, yet it has to lift much more mass, and it has to overcome the drag from a second set of fins. Or else employ a cluster design with strap-on boosters - using the core as the motor that stages, and two or more side motors to help do the grunt work.

A few other nice things about these NE motors is that you can use them in side pods, such as in a micro-scale Titan III-C or a peanut scale Delta-II, and not have to worry about venting the ejection charges, and you can design micro saucers and pyramids without needing to incorporate ejection charge vent holes in the designs. And you can use them in competition rocket gliders and boost gliders to augment the main motor (and bring the total impulse up to the maximum allowed for that class event) without having to worry about what to do with their ejection charges.

A micro Frick 'N Frack? Hmmmm.... :D

MarkII
 
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Is Quest modifying their stock motors post-production, or are these a special line of motors that are manufactured without ejection charges?

Josh: you would have to build the two-stager to be very lightweight (with a small frontal area), because the booster motor has no more power than the regular Micromaxx-II's, yet it has to lift much more mass, and it has to overcome the drag from a second set of fins. Or else employ a cluster design with strap-on boosters - using the core as the motor that stages, and two or more side motors to help do the grunt work.

A few other nice things about these NE motors is that you can use them in side pods, such as in a micro-scale Titan III-C or a peanut scale Delta-II, and not have to worry about venting the ejection charges, and you can design micro saucers and pyramids without needing to incorporate ejection charge vent holes in the designs. And you can use them in competition rocket gliders and boost gliders to augment the main motor (and bring the total impulse up to the maximum allowed for that class event) without having to worry about what to do with their ejection charges.

A micro Frick 'N Frack? Hmmmm.... :D

MarkII

Mark, I've CHAD staged with a small 10.5mm tube fin with a modified MMX II with ok results. I've also done a cheap stick rocket with small scraps of wood as fins on the bottom. I've mounted the motors at the top with fairly good results. One motor at the top, another motor below that, and two to three motors below that.
 
I'm not real concerned, but I would like to know if there is any real data out there.

What would you like? We (S & T) did the certification firings in my basement because these are the only motors that don't have to be fired in the MIT test cell or outside.They perform exactly like the regular MicroMaxx motors. I believe Bill Stine posted something somewhere on this forum where he said that they were just scraping the ejection out of the motors. There is an event at the end of the delay. It's sort of a weak ejection charge. I can think of a couple of Fliskit models that these might be good for. "NE" was the designation that Quest used and we kept it because it's really the only way to describe the motor.

Here's a video of one of the static tests in slow motion. I believe its a regular motor. If you look carefully at the laptop screen in the lower right you can see the thrust time curve being formed.
 
Jim:
I can't speak for Quest; Their web site lists them as NO Ejection - UFO motors.
To be honest; having discussed this Motor method with Bill personally several times, and having used over 70 "test motors" during the last several years. (Both MMX-I and MMX-II's I might add) we've concluded from these tests.

* Leaving the .5-.89s delay makes little if any difference when using these No Ejection MMX-II's as boosters in models from minimum dia to T4 outer airframe sizes. In all but the biggest/heaviest BT-5 & over combinations the models were still going up at a good clip and vertically at staging.

* Burn thur has a slight kick, AS DO ALL "-0" booster motors.

* When used as Staging Boosters, they work quite well over motor with the ejection charge left in.

* I Just recieved my inital order (144) MMX-II-NE's on Friday. had a little snow storm disrupt my intended weekend test flights of these Factory bought motors. but I can assure you they Look and measure exactly like the "experimental Motor" I've personally been flying staged for the last couple years.

I'll be most happy to Post further Fligth data on these -NE Factory fresh motors as I gather it.
Hope this helps.

Obviously: Minimum diameter and T3 OD models had the best flights. As with all Micro's overall Mass is alway to be foremost during design phase. Clusters and strap-ons are also options. I do NOT recommend Chad Staging micro models, Only because of the large amount of extra fin area that should be needed to offset the added aft mass.
 
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John,

Thanks. I will be doing some static testing myself (as soon as I get some of these... :) )

Bill, As far as "data" is concerned, John answered most of what I was looking for as well as he could. What I am looking for is data related to their use as a booster, not so much their performance as a single motor configuration.

Mark II, you mentioned using them in side pods and not having to worry about venting the ejection charge. My understanding (Bill? John?) is that there is enough "blow-through" to make this still a concern. As I recall the motors popped out of the test stand quite forcefully during testing at S&T...

jim
 
The main reason for looking for a clear statement of intended use directly from the manufacturer is so that their use in that manner is still "legal" as a "Model Rocket Motor" in a "Model Rocket" and still covered by insurance.

For instance, we all knew that Aerotech delays could be modified, but until they officially published the info that it was approved to do so and how to do it, we couold not 'legally' do so.

In the past, it was often standard practice to simply go ahead and do something until we were told not to do so. Prime example was "Tandem motors". Once the manufacturer(s) specifically said (not an exact quote, but close enough) "this is not an intended or recommended use of our product", then that was the end of Tandem Motors.

So, if someone is specifically worried about using them in a booster stage, my personal opinion is that the statement on the Quest website would indeed allow this (and my opinion can change if they change their wording) "SPECIAL DESIGN with no ejection charge. For use with rocket designs like a saucer that are tumble recovery." A booster stage pretty much fits that description as it tumbles. The two stage rocket designer must do what they would do with any model of any size and power: choose motors and components that are appropriate for their configuration. If you build it and the weight comes out too high, you either find a motor with more thrust, remove weight or do not launch it.

We know these can be used safely with the appropriate lightweight materials. I expect someone to show up at one of our club launches with one very soon. They will probably fly much higher than anyone expects.

An example of how you cannot use them: Using them in a car would not be per the manufacturer's use recommendation.
 
Mark II, you mentioned using them in side pods and not having to worry about venting the ejection charge. My understanding (Bill? John?) is that there is enough "blow-through" to make this still a concern. As I recall the motors popped out of the test stand quite forcefully during testing at S&T...

jim

There is definitely an ejection like event. None of the motors stayed in the test stand at ejection. If the motor was up against a solid bulkhead and restrained there's a good chance the gas would vent out the nozzle. Actually, it would have to vent out the nozzle because it's got nowhere else to go. Maybe putting a piece of wadding in the top of the motor would keep the "no ejection" ejection charge from toasting the tube.
 
There is definitely an ejection like event. None of the motors stayed in the test stand at ejection. If the motor was up against a solid bulkhead and restrained there's a good chance the gas would vent out the nozzle. Actually, it would have to vent out the nozzle because it's got nowhere else to go. Maybe putting a piece of wadding in the top of the motor would keep the "no ejection" ejection charge from toasting the tube.
Thanks. I was not aware that they retained any ejection-like action at all. Since these are post-production mods (done by the manufacturer), it makes sense that they wouldn't get absolutely all of the ejection charge out. I was also wondering about plugging them, but this would likely cause problems, too. When they were first announced, I thought that the NE motors were a special production run that was made with the ejection charges left out of the process. The introduction of these motors is a very exciting development in the Micro-verse, and I can't wait to get my hands on some, but part of me is just a touch disappointed that they aren't "real" boosters. But only a tiny bit. And that part will probably go into exile once I actually get some of them.

MarkII
 
Uh oh.... "E.L.E." :eek:

Don't let Tea Leoni find out about that.

;)

There is definitely an ejection like event. None of the motors stayed in the test stand at ejection. If the motor was up against a solid bulkhead and restrained there's a good chance the gas would vent out the nozzle. Actually, it would have to vent out the nozzle because it's got nowhere else to go. Maybe putting a piece of wadding in the top of the motor would keep the "no ejection" ejection charge from toasting the tube.
 
Thanks. I was not aware that they retained any ejection-like action at all. Since these are post-production mods (done by the manufacturer), it makes sense that they wouldn't get absolutely all of the ejection charge out. I was also wondering about plugging them, but this would likely cause problems, too. When they were first announced, I thought that the NE motors were a special production run that was made with the ejection charges left out of the process. The introduction of these motors is a very exciting development in the Micro-verse, and I can't wait to get my hands on some, but part of me is just a touch disappointed that they aren't "real" boosters. But only a tiny bit. And that part will probably go into exile once I actually get some of them.

MarkII

Even if they got every last piece of black powder out something would still happen at the end of the delay. It takes pressure to get the smoke through that little nozzle hole. Given the choice it's going to want to go out the big end first. Based on what John says, it sounds like that even though they may not be real boosters they work like real boosters. I've got a two stage model all ready to try but the weather around here hasn't been good for much of anything.
 
Uh oh.... "E.L.E." :eek:

Don't let Tea Leoni find out about that.

;)

Do you get a commission from Google? The Tea Leoni reference got right by me until I looked up e.l.e.

Going on the assumption that I'm not the only one who didn't get it, e.l.e is extinction level event.

Now that I think of it, I still don't understand how that applies to MicroMaxx NE motors.
 
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