Estes Saturn V Tips

Introduction:

Comments are welcome.

Disclaimer: Free advice is often not worth what you paid for it.

Jim Kerns
Sven Knudson
revised 3/97

Contents:

Credit where credit is due:

Sven collected the information from the R.M.R_POSTINGS archive at Sunsite and I re-arranged the articles into categories - doing some editing along the way. Errors, omissions, and inaccurate attributions are probably mine.

This page is maintained by Jim Kerns and Sven Knudson and can be found at:

http://www.ninfinger.org/rockets/rockets.html

J.K.

Other sources of information:

Engines / Motors:

ccorway@calweb.com (CECorway)
A D12-3 engine is barely adequate; you may want to go to a composite E motor for better flight performance.

J.Cook@ENS.Prime.COM (Jim Cook)
Tony Vincent of CMASS regularly flies his Saturn V, though if the wind is bad he will fly it on a D. An Aerotech E15 is close enough to an Estes D12 in average thrust that it will take it.

MSJOHNSON@WichitaKS.NCR.COM (Mark Johnson)
Even an E15 is a bit much for a Saturn, in terms of realistic flight...the initial thrust spike is *way* too sharp. Although it's much smaller, and hence even faster, I didn't like the way a 1/100 Saturn IB boosted on an E15 at all. The E11 would be a much better choice, I think, for both the IB and the V.

gd-smith@uiuc.edu (Greg Smith)
We routinely recommend the Aerotech E15-4 as the single most suitable motor to fly the stock Estes Saturn V.

akhome@aol.com (AKhome)
Recently I launched an Estes Saturn V on an Aerotech E15-4W single-use engine. The combination was GREAT!!!! [...] However, there was some damage to the rocket. The forward bulkhead was blasted up into the 3rd stage body tube by the force of the ejection charge, the engine popped out at parachute deployment, and the inner body cavity was charred and the area just behind the engine mount was charred and peeling. The rocket was otherwise fine.

[note: I've given up on trying to keep the bulkhead on the 3rd stage tube in place - it always seems to break loose J.K.]

leer@fc.hp.com (Lee Reep)
The E30 is pretty "thrusty" -- I'd recommend an E15 if you stick to 24mm motor mount.

whitman@nssdca.gsfc.nasa.gov (Rusty Whitman)
Just be careful with the CG-CP relationship. I have seen Saturn Vs flown with E15 and E30s where the extra weight of the motor and strengthening the mount caused it to be neutrally stable or completely unstable. If you want to fly it with larger than D motors I would add a little weight at the capsule end just to be on the safe side.

>24mm:

bov@fc.hp.com (Bo Viger)
This finished model runs in the 18 ounce range with chutes but w/o motor. Its first flight on an F25 was not *normal* - it moved quickly off the pad but began a radical spiral shaped climb at about 100 feet. I initially thought my transition might be be off (custom plywood centering rings), but I checked the axis alignment of the booster and upper section on an old LP turntable and the rocket proved to be very *straight*. My guess was a clogged or defective nozzle on the motor resulting in asymmetrical thrust. Fortunately, the recovery system worked, although not before the Saturn had arced over (sooner and at a lower altitude than it would have without the spiral flight path) and returned dangerously close to the ground! Whew, 20+ hours of work almost down the drain on the 1st flight! My Saturn's second flight was on an F14, and was one of the most beautiful flights of any single stage rocket I've ever built/flown. The F14's initial thrust spike is slow to peak, resulting in a smooth, majestically-slow launch which never attains any tremendous rate of climb due to the constantly decreasing thrust curve of the F14. A 4-second delay proved to be just right. My next flight will be a G25, with an appropriate amount of nose weight added to return the CG to the appropriate point. BTW, with 2 nylon chutes and an F14 or F25, the Saturn needed NO additional nose weight beyond the empty bolt already there. [See notes on reinforcement below, J.K.]

Motor Mounts / Reinforcement:

kaplowro@hccompare.com (Bob Kaplow)
LOC 3.9" centering rings [...]should fit the BT-101 fine.

J.Cook@ENS.Prime.COM (Jim Cook)
Using epoxy instead of white/yellow glue is recommended and perhaps replacing Estes cardboard motor mount centering rings and bulkheads with light 1/32" or 1/16" plywood might be considered.

jim@commonwealth.net (Jim Kerns)
I've reinforced the motor mount with four strips of 1/8 X 4" end grain balsa epoxied between the mount and body tube and epoxied in a longer engine block tube.

[note: I've heard reports of standard cardstock centering rings glued with yellow glue flying with no problems on 24mm E engines J.K.]

Attaching Paper Wraps:

lynell@cco.caltech.edu (Lynell K. Jackson)
I used this [3-M 77 spray adhesive] for my Estes Little Joe II (tm) and it worked well. However, I also used it for the wraps on an old Estes StarLab I built over a year ago, and one of the wraps has pulled up a little. I probably didn't get a good coat on it because I was worried about sticky overspray. I also haven't painted it yet, so paint may also help keep things stuck down. The lesson is to use a large enough spray area, well protected from overspray, to make sure you get even and complete coverage of adhesive on the wrap. 3-M 77 acts a lot like the self adhesive decals that are used in many Estes kits nowadays, but I don't think floating a wrap on a soapy water film for placement is a good idea. :-) Maybe it's more like a forgiving form of contact cement, since once it is firmly placed it will pull off the glassine body tube coating if you try to pull it up.

petealway@aol.com (Peter Alway)
The "permanent spray adhesive" I used wasn't. [used / suggests white glue - see below. J.K.]

[I also had problems with a spray adhesive (not 3M 77) not sticking well J.K]

White / Yellow Glue:

petealway@aol.com (Peter Alway)
I used wood glue (though wood glue applied directly to paper wraps will wrinkle them--apply it to the body in a thin layer). Wrap the corrugation around dry for good alignment. lift one end and glue it. Re-adjust alignment and allow to cure with a rubber band holding a alignment. then glue the rest of the wrap down.

CyA:

horner@cdc.hp.com (James G Horner)
I used thin CA to put the body wraps on my Saturn V (~15 flights so far!). The technique I used is to place the wrap on the tube in its correct location and hold it in place with a bit of tape along the seam. You don't want to actually tape to the body tube, just hold the edges of the seam together. Then, starting at the opposite side of the tube from the seam, slowly drizzle the CA into the junction of the body tube and the wrap. The CA will wick underneath the wrap and bond it to the tube. It helps to have one of those Teflon tips to make the glue come out in a small stream. You'll be able to see where you need to add glue to get complete coverage. Once the wrap is mostly in place, remove the tape and inject the glue underneath the seam. Sometimes the glue wicks all the way through the paper wrap, so be careful not to touch the wrap where the glue is. You can use paper towels to apply the CA accelerator to the outside of the wrap to speed up the process some.

jkerns1@ford.com (Jim Kerns)
[ditto thin CyA advice... J.K.] But, when I tried it on an Estes Saturn 1B [plastic wraps instead of paper J.K.], the CyA attacked the plastic and I switched to a contact cement.

Epoxy:

petealway@aol.com (Peter Alway)
leer@fc.hp.com (Lee Reep)
Both report that some people use / prefer epoxy.

Scale Accuracy:

petealway@aol.com (Peter Alway)
I just did some digging on the variations from flight to flight after a thread on various Saturn V variants on rec.models.scale.

   Flight    Ullage Rockets   Paint Scheme
   500F      8                black on S-IC intertank 
   (not flown)                unique S-IVB paint job 
   Apollo 4  8                Standard Scheme 
   Apollo 6  8                
   Apollo 8  4                
   Apollo 9  4                
   Apollo 10 4                
   Apollo 11 4                
   Apollo 12 4                
   Apollo 13 4                
   Apollo 14 4                
   Apollo 15 0                
   Apollo 16 0                
   Apollo 17 0                
   Skylab 1  0                

There are white areas on the service module. refer to the launch close-up of the real thing on the box. The pattern repeats at 180 degrees.

If you want to be accurate for Apollo 11, omit half the ullage rockets: Keep those that are nearly in line with the fins. with care you can burnish the remaining locations on the wrap-around to match the surrounding corrugations (those places will be painted black, so flaws should be inconspicuous).

Leave the decal(s) off the nose cone (command module's boost protective cover)

Paint:

Mask with scotch Magic tape (the frosty stuff) and aluminum foil covering the vast white expanses.

Take the effort to sand and seal the fins well. they'll be painted silver, and the grain will really show.

Also, don't try to apply decals to matte paint. Either use gloss paint or spray glosscote before applying decals. Decals on matte paint produce "silvering" from air under the decal. This isn't as conspicuous on white as it is on olive drab, but it still looks bad.

lynell@cco.caltech.edu (Lynell K. Jackson)
[Concerning the matter of painting silver over white as described by Peter Alway above] On the other hand, I hear silver makes an excellent base coat for white. Is it possible that doing the silver first would enhance the look of the white? Maybe even help offset the effects of paint yellowing? But then you have the problems that crop up when masking silver paint. :-( How about silver, then white, then silver again. :-) (no, I don't work for a paint company :-)

horner@cdc.hp.com (James G Horner)
[Sealing fins:] After sanding the fins smooth, I take a piece of silkspan and lay it on top of the balsa. Apply thin CA on top of the silkspan, and work slowly outward from the center. The CA wicks through the silkspan and bonds it to the balsa. When set, one more application of CA and sanding produces a very smooth, no pores finish.

[Clear dope is the traditional adhesive for silkspan. Diluted white or yellow glue also works well J.K]

craddock1@aol.com (Bob Craddock)
For the Service Module color, I suggest getting a bottle of Micro Metal Foil Adhesive and some Reynold's Wrap. Spread the adhesive on the **shiny** side of the foil. The silver on the SM was somewhat dull, and just about ANY silver paint sucks badly! The foil will give you the look you need, and the adhesive is extremely easy to work with. The white radiator details can be added by using shroud line or Evergreen styrene strips. White glue works well with the shroud line, but I would recommend fast epoxy for the strips. Mask off the radiator areas so you can paint them white when you paint the entire rocket.

The decals **WILL** shimmy if you apply them to a flat-colored surface. Spray on a coat of gloss overcoat before laying down the decals. After they've dried, spray the luster down with flat coat. As hard as I've tried, I always manage to make gloss paint run--even Krylon gloss. If you're a better painter than I am (and I'm convinced that most people are), then go ahead with the Testor's classic white. It will take you about 3 bottles of that stuff though.

Recovery:

            +--+ +--+
            |  | |  | <-- rubber band here. +--+ |\\| | | | |="Rolled" up chute |\\| |\\| | | |\\| |\\| +--+ |\\| |\\| |\\| |\\| / & \="Shroud" lines |\\| |\\| +--+ +--+ / \ / \ To lower <-> To upper
   stage                  stage

I've seen one guy use a 29mm mount in his Saturn V, and he used a piston approach to get the chutes out. The only problem he's had is using too long of a delay (ripped the chute off the upper half). Oh yeah, don't forget to add some nose weight!

sfkee@scfn.thpl.lib.fl.us (Manuel Mejia, Jr.)
Widen the hole on the centering rings so that you can use a BT-60 rather than a BT-50 for a stuffer tube. The BT-60 will allow you to insert the booster parachutes into the tube. When I flew my Saturn using the BT-50 tube, the parachutes tended to be blown to the side of the parachute compartment rather than out of the body. The new result--a trashed booster after the first flight.

Launch Lugs:

jim@commonwealth.net (Jim Kerns)
I decided to put the lugs on the inside of the large diameter body tube and cut a "flap" in the paper wrap on the 2nd - 3rd stage reduction that I can open up and let the rod stick through. I did end up with the seam around the flap which doesn't look the greatest but I think it beats the external launch lugs.

What I (perhaps) should have done:
After I did this it occurred to me that a 3 foot launch rod will fit completely inside the rocket if I were to attach the launch lugs to the outside of the motor mount tube and put some holes in the upper stage bulkheads. I would also have to put a small tube for the rod to pass through in the 'chute compartment to avoid skewering the 'chute when it it put on the rod.

rml!jack@lll-winken.llnl.gov
This [referring to Jim Kerns's internal launch lug arrangement] is an almost perfect description of the lug arrangement on my (scratch built) Titan IIIB. It works very well, but I didn't put a continuous tube up the inside, just an intermediate lug about halfway up the stuffer tube. I haven't had any problem "finding" the middle lug when putting it on the rod, but then I used the "table roll" method of aligning them during construction. Since the recovery system is inside the stuffer, there's no problem with skewering the 'chute, either.

kaplowro@hccompare.com (Bob Kaplow)
I've done several internal or disguised launch lugs. The first was on my NARAM-25 Super Scale Conestoga. I used the NCU raceway on the outside of the booster as the launch lug. Only "defects" were the hole in the top and bottom.

My NARAM-30 Giant Scale D Region (BT-80 clone) had a 12" brass tube that fit over a 1/4" rod on the inside. This routed through the motor mount bulkheads. Since my coupler was rolled VMS manual inserts, the launch rod could go all the way up to the nose cone. The model was about 5' tall, so I could use a 4' rod. Only "defect" on this model was a hole in the bottom bulkhead. Many of my Crayon conversions with stuffer tubes have the launch lug along the stuffer tube. The only problem here is that I used a couple inches at the top, and a couple more inches at the bottom (too cheap, and besides, where do you get a 36" launch lug?). Made some fun threading the model on the rod.

All the above have worked fine in flight.

bov@fc.hp.com (Bo Viger)
Ditched the launch lugs and ran a ~28" long aluminum tube through the motor mount tubes (all 3) and up to, but just below, an elliptical hole cut in the transition shroud (didn't bother with a *flap*). This made necessary another hole through the rear bulkhead of the upper (3rd stage) section of the Saturn. The aluminum tube runs right along the airframe wall to insure plenty of room for the two parachutes.

Important note: