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Estes Saturn V 2157 Advice Sought

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DBB

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I'm getting interested in the hobby again and new to the forum. Other than launching a RTF Patriot rocket (fun, but I'm not sure it counts), I haven't built or launched anything in 30+ years. I lived this stuff as a kid, did demos at 4H Camp, etc. I never tired of the "yellow pages" that Vern used to stick in the middle of the catalogs... I never really built anything complex, although I used to drool over the Saturn V, the Camroc, and some of those really cool rockets that I never could afford.

Now I have a son, and thought it would be a great thing to do together and with his Cub Scout pack, but who am I kidding? It's a convenient excuse... :rolleyes:

So now I have acquired a couple Saturn V 2157 kits, still in shrink wrap, and a dilema on my hands.

I thought I might build one and keep the other intact for either eventual spare parts, or as a collector's item. But one I definitely would like to build. I've read the forums, visited countless sites, but am more confused than ever.

Seems like the one point that always surfaces is that this rocket is fairly heavy, and really warrants something more than the stock D engine. I'm not necessarily interested in the 1000 ft. altitudes some of the upgrade kits tout (I'd just lose the thing), but I'd like some decent thrust to lend additional stability. ...And it's perpetually breezy here.

  • Do I attempt a cluster, and if so, what configuration and directions should I follow? I've never clustered before and so would need some solid advice here regarding igniters, batteries, and engine mounts. I'm not sure I understand how to get all engines to go simultaneously, or is it simply left up to the ingiters in hopes that they all go at roughly the same time? Do I really have to invest in a car battery?
  • Have also heard folks talk about scrapping the external launch lugs and crafting an internal tube to allow the rocket to slide over the rod, making for a more realistic looking rocket. I don't like the thought of having external lugs on this rocket either. Or should I maybe just try some rail buttons?
  • As far as paint and finish, I've seen a few posts on filling tube spirals, which is new to me. Does everyone really use Bondo and Kilz primer for this?
  • Am also interested in incorporating some kind of electronics, mainly for tracking. Any schematics or inexpensive kit suggestions would be appreciated. I can etch my own PCB and solder, if need be.
I've always seemed to be pretty good with my hands and being somewhat of a tinkerer, have lots of tools around, so modifications don't worry me that much, as long as I've got good direction. I'm not interested in 3-staging, etc., but would welcome any suggestions that would fix shortcomings this kit might have.

As mentioned, I've visited lots of sights and forums, and have picked up lots of bits and pieces, but I need some solid, basic advice and/or links to set me on my way to a successful build - and hopefully - launch. I think I would literally get sick if the thing got lost or did a death dive right off the rod...

Sorry for the lengthy post. I really appreciate any and all advice.

DBB
 

CharlaineC

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Well you could use e motors in her or a d/e cluster. but before you start this kit build a few others first to rehone your building skills. try bulding a few semi scale or smaller scale rockets first as she is daunting and demanding, and can very easily through one for a loop. she is a rocket that myself and many others have in different stages of compleation. mine is waiting for roll patterns and decals. . and by the way welcome to the forum
 

Peartree

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WillMarchant

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Welcome back! The motor situation has changed a lot since you were last here. :clap:

The Estes "mighty D" motors, while still fun, have been eclipsed for use in these heavier models.

In particular the Aerotech 24mm re-loadable motor is size compatible with the Estes D but has 8 different reloads available for it ranging from the D9 to the F39.

Aerotech (http://aerotech-rocketry.com/) has created this site http://www.valuerockets.com/ to lure you into the wonderful world of re-loadable motors!
 

mach7

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Welcome! You have come to the best place. I just finally finished my Saturn V after 10 years. like you I got it after becoming a BAR. You can follow the later stages here:

http://www.rocketryforum.com/showthread.php?t=505&highlight=mach7

First off let me say this kit can be daunting, but it is really not difficult. just take it in stages. Take your time and you will have a great kit.

I went with a cluster, this was my first cluster. The advice I got here was invaluable. We have a huge braintrust here. I scraped the vac u form fins and went with resin aftermarket from moldin the oldies.

If I were to do this again, I think I would use an Aerotech 24mm.

Mark
 

dedleytedley

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Hi DBB welcome to the forum. I have a Saturn 5 of the same model that I bought already built on E-bay. Probably the smartest thing you could do is purchase an Aerotech Mantis launch set. The Estes launch set you likely have can tip over easily with a big rocket in the wind and it doesn't have the power to ignite either an AT motor or a BP cluster.
The Aerotech E-15-4 or E-30-4 will get it up nicely and won't require any mods to the rocket. Clustering can be difficult without some experience but you may find you'll wish it was a cluster later. Cygnus rocketry makes a 24mm+4x18mm for the BT-101 but the extra weight of motors will require some Re-balancing of the rocket. Maybe you could build it with a quick-change motor mount. As for launch lugs you could use the wiring tunnel? between the first and second stages as a place to mount a long 3/16" LL.
Many flyers build the Saturn 5 with the LES removable for flight as it often takes a beating. I gave up on re-building mine.
As far as electronics, a GPS or radio tracker won't be of much use for this rocket. With it's large size and relatively low altitude it is pretty hard to lose. Quest has an inexpensive altimeter the "How High" that would be a better payload. That's my :2:. Happy Building! Ted
 

DBB

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WOW! Looks like I came to the right place! Thanks so much for responding, everyone! I hope that, once I get through this build, that I can contribute to someone else's 2157 experience. Maybe I can take some photos and notes along the way...

I've commented on some of the points each of you have contributed.

Thanks, again!

DBB


Well you could use e motors in her or a d/e cluster. but before you start this kit build a few others first to rehone your building skills.
Thanks for the welcome, CharlaineC! Sage advice, but I think I'm going to collect all the info I find, plan a direction, and jump in with both feet, otherwise, I'll probably never get it finished! ;)


Welcome to the forum! There isn't a lot on this subject (that I could find) but you will often find very useful information in our archive. A quick search brought these threads...
Thanks, Peartree! Lots of good stuff here. I searched this forum before posting, but as you say, didn't turn up very much. I didn't see the archived things, though.

I think I'm going to have to print off all the posts and replies and create a reference of some sort...


Welcome back! The motor situation has changed a lot since you were last here. :clap:

In particular the Aerotech 24mm re-loadable motor is size compatible with the Estes D but has 8 different reloads available for it ranging from the D9 to the F39.
I'll say things have changed! [FONT=Verdana,san-serif]Re: the Estes Saturn V, the one fairly common thing I've found across all the sites I've visited, is that the Aerotech 24mm seems to be a popular motor for these. Maybe because no mods are required?

One of the links that Peartree referenced below details the "2157-as-lawn-dart." Looks like the guy was using a F40-4W RMS[/FONT] (Aerotech?) in which the ejection charge failed...

Not sure what 'RMS' stands for, but are the Aerortech motors all reloadable, or otherwise reliable? If reloadable, I imagine that the failed ejection charge could be attributed to a faulty reload caused by the user, but I'm not familiar with what reloading entails.

Thanks for responding!

I went with a cluster, this was my first cluster. The advice I got here was invaluable. We have a huge braintrust here. I scraped the vac u form fins and went with resin aftermarket from moldin the oldies.

If I were to do this again, I think I would use an Aerotech 24mm.
Thanks for the reply, Mark! So the single Aerotech 24mm instead of a cluster? What made you change your mind after the fact? Is it just too much of a headache to mess with the multiple engines each time you launched? So which AT 24mm would you go with?

Will check into the Moldin' Oldies fins. I hope I can get this kit completed before my 8 year old graduates from college! :eek:


The Aerotech E-15-4 or E-30-4 will get it up nicely and won't require any mods to the rocket. Clustering can be difficult without some experience but you may find you'll wish it was a cluster later. ...Maybe you could build it with a quick-change motor mount.
Thanks, Ted! Where would I find info on building a quick-change motor mount? I'll also check into the launcher you mentioned. Believe it or not, I still have the old red Estes Porta-Pad that I got when I was a kid, as well as the tripod that came with the Patriot RTF. I don't think either could be used for the Saturn, though!

Any good references to using the wiring tunnel for the rod, or using an internal, full-length tube for the rod?
 
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jflis

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DBB,

First, welcome to TRF and *back* to rocketry :) You're going to love both and, as you can clearly see, you can get fast response to your questions here!

Next, RMS stands for Re-loadable Motor System, meaning that you purchase a motor casing (they can be pricey) and then you purchase Re-Loads for it. The casing is reusable and the reloads can be quite inexpensive making it far more cost effective to fly larger motors like E, F and above. What you (and everyone else) is most familiar with are the Single Use motors, often referred to as SU motors.

Now, as for the Saturn V, the 24mm D, E, and F motors that are available are your best bet but if you are looking for that added challenge I can't say enough good about clustering three 18mm C6 motors. However you will find more choices in the 24mm selections than you will for 18mm clusters.

Lastly, your thoughts about posting a build thread with pictures, of your Saturn V. Such things are pretty much mandatory around here and build threads with pictures pretty much elevates members to hero status, so... :)

Bottom line, have fun, read, contribute and welcome!
jim
 

DBB

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...but if you are looking for that added challenge I can't say enough good about clustering three 18mm C6 motors.
JFlis, this is the thing that concerns me about clustering: not really understanding how one goes about firing a cluster, I'm assuming that the igniters are wired in parallel or series with one another, and one simply hopes that they all fire more or less simultaneously.

If my understanding of clustering is correct, then it would seem that - at worst case - the engines chosen for a cluster would have to individually be able to carry the rocket to a safe altitude (for delay and chute deployment) all on its own, if only one of them fired.

Is this a correct assumption, and if so, would a single 18mm C6 do that?

Thanks,
DBB
 

dedleytedley

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I would suggest searching the archive for info on making a quick change mmt. Basically you use stops of some kind(C.ring,wooden tabs) glued to the B.T. to restrain the mmt's forward motion and retain it at ejection with notches in the mmt to fit past tabs glued in where the lower C. ring would sit(see removable bulkhead pic).
The wiring tunnel I'm referencing is made from a balsa strip 1/4x1/8x14?" long mounted to the B.T. near the III decal. You would use a 3/16x14" length of LL in place of the balsa strip.
In most clusters if one motor doesn't fire the rocket will likely do a powered dive into the ground, the exception being a canted motor cluster. Clusters are best lighted with a clipwhip but you can wire the igniters together in PARALLEL not series. I've heard that some people use a flash pan type of system, one motor of the cluster fires causing a pan or spider of black powder to ignite lighting the rest of the motors in the cluster. Quest Q2G2 igniters would be ideal for your cluster as the long insulated wires are easy to wire together. If you use Estes igniters you will need to prevent the bare wires from touching where they shouldn't and shorting the rig. Ted

interstage with bulkhead.jpg
 

dpower

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JFlis, this is the thing that concerns me about clustering: not really understanding how one goes about firing a cluster, I'm assuming that the igniters are wired in parallel or series with one another, and one simply hopes that they all fire more or less simultaneously.

If my understanding of clustering is correct, then it would seem that - at worst case - the engines chosen for a cluster would have to individually be able to carry the rocket to a safe altitude (for delay and chute deployment) all on its own, if only one of them fired.

Is this a correct assumption, and if so, would a single 18mm C6 do that?

Thanks,
DBB
For this rocket, a single C6 is not enough to lift, you'd need at least 3 of the 4 to light. Clustering is done with igniters in parallel (except in very unusual circumstances, like dozens of motors on a single rocket). You do hope that all igniters fire simultaneously, but the odds are very high with proper preparation. You'll find lots of stuff on clusters if you search, but the basics:
- For reliable BP (Black Powder) cluster ignition, a 12V battery is required.
- A relay system is nice, but isn't necessary if the wires from the battery to the igniters are thick enough and not too long (I use a 30' 16 gauge extension cord).
- Igniters can be either wired together, or a clip-whip can be used. I've used both with high success rates.
- Clean the clips with sandpaper
- Check igniters individually for continuity
- Make sure igniters are not shorted (estes igniters are easy to short if you're not careful)
- Check the nozzles of the motors, I usually (and carefully) scratch up the surface of the BP just a bit to remove any oxidation that might be in there.
- Put a small bit of recovery wadding on the top of each motor, and a tiny bit of tape, so that if one motor doesn't light, the ejection charge from the others won't light it from the wrong end. (rare, but it can happen).

Estes and FlisKits both have a nice clustering paper, though to get the flis one you might need to buy one of Jim's cluster rockets (Everyone needs a deuces wild anyway!).
 

rocketguy101

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JFlis, this is the thing that concerns me about clustering: not really understanding how one goes about firing a cluster, I'm assuming that the igniters are wired in parallel or series with one another, and one simply hopes that they all fire more or less simultaneously.

If my understanding of clustering is correct, then it would seem that - at worst case - the engines chosen for a cluster would have to individually be able to carry the rocket to a safe altitude (for delay and chute deployment) all on its own, if only one of them fired.

Is this a correct assumption, and if so, would a single 18mm C6 do that?

Thanks,
DBB
DBB: check out this tech report (here is the pdf version)

I flew my Centuri 1/100th Saturn V (build thread) on both a C6 cluster and an F20-4.

The cluster makes an impressive amount of fire and smoke -- try it, you'll like it!
 

Commonwealth.Net

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We offer several upgrades on our Ebay site.

Search Ebay for Piestrak Hobbies, we offer 3 upgrade kits.

This kit should never be built stock!
The chute opens about 10 feet from the ground, who wants a 100 foot flight ?


Good luck
 

DBB

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I flew my Centuri 1/100th Saturn V on both a C6 cluster and an F20-4. The cluster makes an impressive amount of fire and smoke -- try it, you'll like it!
Thanks for the tech report and build link, RocketGuy101! I just read through your entire build - very cool, indeed! Great job!

I've got a lot more research to do on the clustering thing, but it intrigues me. I really like the idea of interchangeable motor mounts, as suggested by DedleyTedley.

I've been thinking about the painting, much as you did, and how my previous experience using the blue painter's tape gave less than satisfactory results. I always seemed to get a certain amount of bleed under the edge of the tape, no matter how carefully I applied it. I saw on another post where the builder would first use clear for the first coat (the clear would bleed, but essentially seal the tape edge) prior to going with the color, making for a nice, crisp edge.

Reading through your build, I think I'm going to spring for the Tamiya Masking Tape, though.

I also see that Tamiya makes a basic putty that sands easily. While probably used with plastic models, I wonder if this would be a good candidate for filling the tube spirals? Or should I stick with Bondo?

And here's another question for everyone: I've seen references made to filling the rocket with the expandable foam used to insulate cracks, etc. Apparently, it lends sturdiness and durability to the rocket. Anyone ever try this?

DBB
 

rocketguy101

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I did not foam my Centuri model -- the tube is so thin, it has "popped" some cracks in the paint (of course landing on its side in the grass after falling a couple hundred feet didn't help :) )

I read somewhere (probably in the TRF archives) that the "stuff" in the can you buy at Wally World, Home Depot, etc. may not set up correctly in an enclosed space. People were recommending using two part foam...if I did not remember that correctly, I hope somebody will rectify that (hey, I am 52, I got excuses for creaky memories!!)

I am trying "frog tape" to mask the big areas of my 1/100th Saturn 1B clone (build thread) -- I will report back on how it does. The Tamiya is going on all the detailed areas, it is great stuff!
 

jflis

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JFlis, this is the thing that concerns me about clustering: not really understanding how one goes about firing a cluster, I'm assuming that the igniters are wired in parallel or series with one another, and one simply hopes that they all fire more or less simultaneously.

If my understanding of clustering is correct, then it would seem that - at worst case - the engines chosen for a cluster would have to individually be able to carry the rocket to a safe altitude (for delay and chute deployment) all on its own, if only one of them fired.

Is this a correct assumption, and if so, would a single 18mm C6 do that?

Thanks,
DBB
As others have said, the igniters are wired in parallel.

It's not so much that the igniters fire simultaneously just that they fire fast enough to get that last motor lit before the stack leaves the pad. For something like the Saturn V your odds actually go UP because it is very slow off the pad (as compared to a minimum diameter, light weight bird)

You also help your odds by having clean clips, good power source (I never use anything less than a fully charged car battery), etc.

I have attached a copy of our hints sheet on clustering. This should help.

For those of us who cluster we do so because of the challenge (mostly) and also because of launhces like this one... :D

Here's a close up...

Here are a couple of other launches that show the excitement (to go with the risk) of clustering:

Deuce's Wild! (2 canted motors)

Saturn 1B on a cluster of 4 motors

View attachment hnt-sl3cl.pdf
 

DBB

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I would suggest searching the archive for info on making a quick change mmt. Basically you use stops of some kind(C.ring,wooden tabs) glued to the B.T. to restrain the mmt's forward motion and retain it at ejection with notches in the mmt to fit past tabs glued in where the lower C. ring would sit(see removable bulkhead pic).
Hey, DedleyTedley, do you have any more detail or other photos on how to build your quick-change motor mount? I didn't find much searching the forum, but did find a site that sells kits: http://tmrk.rocketshoppe.com/parts.htm

I suppose I could stick with the one 24mm and use an E, like others have suggested, but I really like your idea. Either way, I still need to figure out how to re-calculate CG/CP if I'm moving too much away from stock.

DBB
 

JRThro

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OMG!!! That is INSANE...! LOL Is that an available kit, or scratch-built? Unbelievable!
That is Boris Katan's (TRF member delta22) scratch-built rocket whose name escapes me, but it was featured in an article in Sport Rocketry (http://www.nar.org/SPR/index.html) earlier this year. I believe it had something like 30 motors in it. Which, yes, is totally insane.

Also, here's a thread that talks about clustering: http://www.rocketryforum.com/showthread.php?t=2260

Speaking of having all of the motors light before the rocket leaves the pad (or at least the launch rod), I have launched my 4-motor cluster rocket once (so far) using 4 C6-5's, and it lifted off slowly enough that I could see the 4th motor finally ignite as the rocket was moving up the rod... which is at least part of the reason that it was lifting off so slowly. It had a nice high flight and drifted far enough that it took me a good 20 minutes to find it and carry it back to the launch area (on TRF member luke strawwalker's family farm, btw).
 
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JStarStar

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I'm getting interested in the hobby again and new to the forum. Other than launching a RTF Patriot rocket (fun, but I'm not sure it counts), I haven't built or launched anything in 30+ years. I lived this stuff as a kid, did demos at 4H Camp, etc. I never tired of the "yellow pages" that Vern used to stick in the middle of the catalogs... I never really built anything complex, although I used to drool over the Saturn V, the Camroc, and some of those really cool rockets that I never could afford.

Now I have a son, and thought it would be a great thing to do together and with his Cub Scout pack, but who am I kidding? It's a convenient excuse... :rolleyes:

So now I have acquired a couple Saturn V 2157 kits, still in shrink wrap, and a dilema on my hands.

I thought I might build one and keep the other intact for either eventual spare parts, or as a collector's item. But one I definitely would like to build. I've read the forums, visited countless sites, but am more confused than ever.

Seems like the one point that always surfaces is that this rocket is fairly heavy, and really warrants something more than the stock D engine. I'm not necessarily interested in the 1000 ft. altitudes some of the upgrade kits tout (I'd just lose the thing), but I'd like some decent thrust to lend additional stability. ...And it's perpetually breezy here.

  • Do I attempt a cluster, and if so, what configuration and directions should I follow? I've never clustered before and so would need some solid advice here regarding igniters, batteries, and engine mounts. I'm not sure I understand how to get all engines to go simultaneously, or is it simply left up to the ingiters in hopes that they all go at roughly the same time? Do I really have to invest in a car battery?
  • Have also heard folks talk about scrapping the external launch lugs and crafting an internal tube to allow the rocket to slide over the rod, making for a more realistic looking rocket. I don't like the thought of having external lugs on this rocket either. Or should I maybe just try some rail buttons?
  • As far as paint and finish, I've seen a few posts on filling tube spirals, which is new to me. Does everyone really use Bondo and Kilz primer for this?
  • Am also interested in incorporating some kind of electronics, mainly for tracking. Any schematics or inexpensive kit suggestions would be appreciated. I can etch my own PCB and solder, if need be.
I've always seemed to be pretty good with my hands and being somewhat of a tinkerer, have lots of tools around, so modifications don't worry me that much, as long as I've got good direction. I'm not interested in 3-staging, etc., but would welcome any suggestions that would fix shortcomings this kit might have.

As mentioned, I've visited lots of sights and forums, and have picked up lots of bits and pieces, but I need some solid, basic advice and/or links to set me on my way to a successful build - and hopefully - launch. I think I would literally get sick if the thing got lost or did a death dive right off the rod...

Sorry for the lengthy post. I really appreciate any and all advice.

DBB
I have a Centuri Saturn V (the kit the Estes 2157 is based upon) which I got as a gift from my grandmother for Christmas 1969, and finally got around to building in 1994.

I built it stock, but installed a 24mm mount to use Estes E's. As virtually everyone agrees, the finished model almost always weighs in significantly over its listed weight. In addition, the Saturn V is marginally stable to start out with, and generally some nose weight must be added for stability (thus increasing the takeoff weight).

At the time, Estes had an E15 engine which flew the Saturn V fairly well (not real high, but high enough to get the chutes out on an E15-4). However, those engines have since been withdrawn from the market (they used to have problems with chronic CATO blowouts) so they are no longer an option.

The current Estes E, the E9, does NOT have enough power to get the Saturn V into the air with enough airspeed to be stable. I have a Maxi V-2 of similar size and weight, which I have flown a few times on E9's, and it's a white-knuckle experience. It chug-chug-chugs off the launch rod, struggles up into the sky, and usually keels over in mid-flight, culminating in chute ejection 20 feet off the ground (if you're lucky).

That's OK for a V-2 which is an OK rocket but not a collector's item; I'm not going to try it with a 40-year-old rocket which is kind of irreplaceable.

The Aerotech single-use motors recommended above (E15-4 and E30-4) have enough kick to get the Saturn V off the pad with enough speed to be stable, and avoid the ignition problems of clusters.
 
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dedleytedley

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Hey, DedleyTedley, do you have any more detail or other photos on how to build your quick-change motor mount? I didn't find much searching the forum, but did find a site that sells kits: http://tmrk.rocketshoppe.com/parts.htm

I suppose I could stick with the one 24mm and use an E, like others have suggested, but I really like your idea. Either way, I still need to figure out how to re-calculate CG/CP if I'm moving too much away from stock.

DBB
Hi DBB I'll start by saying I haven't built one of these yet but I would begin by deciding where the ejection gas from the additional motors will go or if they will eject. The kit uses a stuffer tube from the upper MMT ring to the parachute compartment. If you decide to omit the stuffer tube will the pressure from a single 24mm deploy the chutes? Or will you make a compartment to collect the ejection gas and vent it through the stuffer tube? Either way you will need an extra 3.9" O.D. centering ring and they are hard to find for low power.(BMS?) Let me know what you want to build and we'll go from there. Ted
 

DBB

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I would begin by deciding where the ejection gas from the additional motors will go or if they will eject.
Not sure I'd want to eject the motors; sounds like an extra potential fire hazard.

The kit uses a stuffer tube from the upper MMT ring to the parachute compartment. If you decide to omit the stuffer tube will the pressure from a single 24mm deploy the chutes? Or will you make a compartment to collect the ejection gas and vent it through the stuffer tube? Either way you will need an extra 3.9" O.D. centering ring and they are hard to find for low power.
I don't think I know enough about all this to even choose a direction, here. I think I need to find a glossary of terms, as well as a general discussion of typical motor mount design, just to familiarize myself with the setup. Remember, it's been 30+ years... I barely remember how I mounted a single engine in my little rockets!

Let me know what you want to build and we'll go from there. Ted
Given my lack of knowledge and reading JStarStar's excellent post, I think the safe bet would be for me to start with a single 24mm removable mount. Even though I may never cluster, at least I would have the option to do so - provided the mounts accommodate the ejection gasses, as you've pointed out.

So now what? LOL
 

Mikus

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Given my lack of knowledge and reading JStarStar's excellent post, I think the safe bet would be for me to start with a single 24mm removable mount. Even though I may never cluster, at least I would have the option to do so - provided the mounts accommodate the ejection gasses, as you've pointed out.

So now what? LOL
Do like me and stick the Saturn V back up into the closet then find some other (i.e. cheaper) kits to build back up your rocketry skills. :)
 

DBB

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Do like me and stick the Saturn V back up into the closet then find some other (i.e. cheaper) kits to build back up your rocketry skills. :)
Well, it would seem I have bigger issues...

After reading elsewhere on this forum about the Estes Saturn V kits being opened, pilfered, resealed and sold, I thought I should take stock. I opened the one kit I had planned on building (it had a tear in the shrink wrap - the other one looks pristine, so I left it wrapped). Luckily, all the parts are there, but the main body tube has a pretty healthy crease in it mid way down. One of the vacuform fins is a little dinged up, too.

I've seen BT-101 tubes through TotallyTubular, etc., but none are of the 24.75" length that came in the kit.

Anyone know of a good place for the Estes 2157 BT-101?

Thanks,
DBB
 

DBB

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Ok, I think I have decided upon a direction for this 2157 build, based on all the kind and informed input I've been given here...


  • I will replace the damaged stock BT-101 tube with the (slightly) shorter one obtained from Semroc (see my 10/5 post - thanks, Fred22!).
  • I will obtain and use the (heavier) Moldin' Oldies fairings and capsule from Siruis Rocketry.
  • I will stick with JStarStar's recommendation of staying with the stock 24mm MMT for use with the Aerotech E15-4 or E30-4, BUT I would like to incorporate this as a quick-change mount as suggested by DedleyTedley, in case I ever want to cluster, or cluster purely for effect, as suggested in the last paragraph of the http://www.rocketreviews.com/images3/est_saturn_v_answer2.txt link.
    • I will need assistance with this quick-change mount, and how to design it to accommodate ejection charges contained in possible future clusters, OR pointed to the proper commercially available mount, such as those found at http://www.truemodeler.com/, which I'm leaning toward for simplicity. Either way, I would like all centering rings and MMT parts to be wood rather than cardstock.
    • Rather than use the stock tri-fold 'chute mount method, I thought I might want to attach shock cords to the MMT, while avoiding the chances of any zippering, if possible (does everyone use the stock external forward attach point for the upper stage?). Would like to also replace the stock chutes with nylon or other durable material.
  • I would like to display and fly the rocket with the F1 engine bells for realism.
  • Per Verna, I will be good as long as I keep the CG 17.5" forward from the bottom of the fairings. Does CP then take care of itself? (By the way, has anyone checked out tungsten for adding weight to the nose? It's more dense for its size than lead, safer, and can be had as disks, cylinders, putty, etc. It's carried on many Pinewood derby supply sites - we took first in our Pack last Spring..! ;)).
My wish list probably exposes my naiveté, but are ALL these points realistically achievable?

Am anxious to get started. Thanks everyone!

-DBB
 
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