This was my first thoughts after I read the article.
This is what I have always said to myself if this kit comes back there are smart guys on this forum to get it flight worthy.

I don't think it matters so much what you put there, but that whatever it is, it is readily accessible and replace-able. Years ago, the recommendation I got was to cut some card stock, roll it up, and insert it just ahead of the motor.

So design the motor tube accordingly to accept that. This means leaving out the forward motor block and instead using an aft thrust ring on the motor (ie, 3 wraps of ¼" masking tape). This will make it much easier to insert and remove the paper roll.

HTH.

Doug

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YORF member #11

Stage coupler is exactly what I was thinking for making a "D10/D21-resistant" Nova Payloader. My current one has bubbled paint just ahead of the motor mount from several D10-7 flights (but so far it hasn't burned through). The Astrobeam burned through the BT-20 "stuffer tube" in one D10-5 flight and the replacement ST-7 in the rebuild is visibly discolored/charred after one such flight. There a long JT-20 would seem to be one way to make it work. BMS has long coupler stock, IIRC.

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Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE

I have looked over the plans of the Vostok, and I see some items that could be left off to make it a litter rocket.
Vostok Plans: http://www.oldrocketplans.com/mpc/m...0/mpc3-0700.pdf

For those who are planning to install a heatsheild to protect against the Hibachi Effect, remember that this is an MPC kit, so it uses similar construction as AVI and QUest rockets: 18mm motors are installed in a BT-20 sized motor mount tube, but that is then glued inside a slightly larger tube that forms the main internal body tube.

BT-20 = T19 (19mm tube)

telescopes inside T20 (20mm tube)

SO, the heat sheild could simply be a longer BT-20 sized motor mount tube with a length of spent 18mm motor casing glued inside as the thrust ring.

Of course, this will add MORE weight to the already grossly overweight rocket, but if flying with D10 motors that will not be a problem.

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-Fred Shecter NAR 20117 (L2)
Southern California Rocket Association, NAR Section 430

Provided that its location does not shift the CG too far rearward.

The best solution is a piece of lightweight and fire resistant insulating material rolled inside the tube. The combination of BT-20 and coupler stock might work.

Or wait until someone brings the C5-3 back to market...hey, whatever happened with those German composite 18mm motors?


Bill

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If your June, July, August and September was like this, you might just hate summer too...

Please unload your question before you ask it unless you have a concealed harry permit.

: countdown begin cr dup . 1- ?dup 0= until cr ." Launch!" cr ;

Give a man a rocket and he will fly for a day; teach him to build and he will spend the rest of his days sanding...

That is how G. Harry Stine kept the insides of his (BT-20 size) experimental gap-staged boosters from getting charred by the upper stage exhaust plumes, as described in his "Handbook of Model Rocketry." He cut out bond paper liners that, when rolled up and inserted down into the booster tube (to butt against the top end of the booster motor and be just flush with the lower edges of the pressure relief vent holes immediately below the upper stage motor), made the booster airframes last indefinitely. He changed the liner after each flight.

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Humn. His 'Hibachi Effect' must be what caused some melt in the plastic BT of my Estes Vampire, alongside the engine?

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BAR after a 29 year absence. Using my plastic, resin & vinyl kit building skills (and my paycheck)
to build what I could only dream of as an 11 year old...

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Yes. Even for black powder motors there is considerable (and quite frightening) delay afterburn of the delay material around the outer edge of the inside of the casing. It burns in a dome shape, so the edge remains after ejection and burns like a highway flare.

Worse if the motor is filled to the end like an A10-3t or a C6-7 or a D12-7.

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-Fred Shecter NAR 20117 (L2)
Southern California Rocket Association, NAR Section 430

A10-3T would be the motor for Vampire, absolutely.

So, would getting some Nomex fabric and insulating the area with it during construction be generally a good idea in these instances? Perhaps shredding it into a batting-like material, to increase the area and decrease the weight? Or would that decrease the heat resistance of the material to an extent that it would be ineffective as a heat insulator?

__________________
BAR after a 29 year absence. Using my plastic, resin & vinyl kit building skills (and my paycheck)
to build what I could only dream of as an 11 year old...

My Rocketreviews.com Gallery