Breaking down an Estes Engine

Ok,

I'm getting ready to try the 3 stage Saturn again. On the first 2 attempts, I was 6 out of 11 and then 9 out of 11 respectively. The only problem I'm still having seems to be core engine ignition. I'm chad staging and I'm going to use 4, B4-2's, on the 2nd stage because the nozzle openings are larger than a B6, but I still have to use a B6 for the core.

I've stripped an Estes B4-2 engine casing and broken everything down into separate parts. My question is, how do I safely convert the bp slug back into a powder? I want to stuff the nozzles of 5 B engines with bp, in order to make staging a little more reliable. I've already had some success just using the standard methods used on any other chad staged rocket, so hopefully this will make it 11 out of 11.

I've thought about shaving it down with an exacto knife or slowly and carefully crushing it with pliers.

Any suggestions?

Randy

Dampen it with water, don't grind on dry powder.

Randy...

Couldn't you just sand it back down with sandpaper? I doubt there is enough friction heat to set it off.

Did those methods include painting the nozzle, throat, and exposed grain of the upper engine(s) with pyrogen? That might be considerably safer and easier than grinding up BP grains.

I think you risk blowing apart the nozzle by doing this.

You can buy a can of 4F black powder at a lot of sporting goods stores that sell guns. At least you could four years ago. This would be far safer than trying to grind up solid black powder.

Brian Elfert

very posible

why?

DON'T ther aint no way you can assure you wont get voids, have too loose bonding to the casing, and other such nightmares, let alone the fact that the stuff aint all that stable.

my bet, flush it down the drain and get another engine. safer that way. trying to re-use it will most likeley CATO and destroy your rocket.

I don't think you need to *stuff* them. others have mentioned painting them with pyrogen

Good luck. let us know how the results are.

Repeat DON'T re-use the engine.

I think he wanted to use the BP from the engine propellant as "staging pyrogen", not try ro reinstall it in another engine as propellant...

-dave w

Soak with a 50/50 mixture of naptha-gasoline, then use a cutting torch.

Ok, I have had my fun. Are you serious? If so, use some pyrogen.

post pictures and videos of the flight. they will probably be instructional and entertaining ( and possibly serve as a warning to others )

Well, how did it go? Whatsa matta...chicken? ;-)

You can crush the plug between two blocks of wood without much danger. Wear eye protection, gloves and work in a fire-safe area. Place the plug between the two blocks and add your weight until it breaks up. If it did blow, though highly unlikely, it will blow out sideways and will not really kick back much at the blocks. I work with BP all of the time. Steel and BP don't get along well together. Brass, wood and aluminum are the prime choice of tools.

Correct.

Randy

I was thinking brass.

Randy

I think what I'll do is add some small particles to the tops of the boosters. All I'm looking for is a few more hot particles, to make sure something gets into the nozzles of the next stage. I'm not going to compact anything in the nozzles.

Randy

If going this route, how about Pyrodex-P? Unlike BP you can get it by the pound in any K-mart/Wally World/etc and it's officially "non explosive". That ought to give you the ignition spark you're looking for with less chance for a cato.

Chuck

sell guns. At least you could four years ago.

Why not just use some loose 4F black powder instead of trying to regranulate BP that has already been consolidated into a large propellant grain?

-dave w

I had some extra engines on hand. It was here. ; )

Randy

Hi Randy-

Back when I was a youngster (about 12) I got into my motors with a friend and we would use a hammer to crush the casing and the powder would come out for us to burn. When my father and mother found out, I was, to put it mildly, disciplined ( this was prior to the new wave anti-corporal punishment wave we are in now). Thankfully, neither I or my friend exploded or burned. I mention this because after that experience, I feel that the motors are safe from ignition without vigorous friction. Having said that, I also believe that God watches over fools and children, obviously I qualified for both which explains how I escaped injury. Hence, something short of using a hammer has at least one point of reference where the motor was not initiated. Just my thoughts, but whatev er you do, be very careful.