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Posted
Assuming you're using Borosilicate glass(pyrex, bomex, nomex, etc), you should be fine with it straight on the plate. If you feel uncomfortable with it, placing the beaker/flash/jar in a bowl of sand will essentially eliminate any sort of thermal breakage if thats what you're worried about.
Posted

Yeah mine is like a weird enamel type coating.. but its kinda messed up in the center... and yeah the dish of sand thing works wonders... especially when you need to heat a RBF and you don't have a heating mantle for that size... much less temperamental than a container of water...

 

So yeah the 2 50g batches of whistle are drying in my new temporary drying box... a PC fan C-clamped to a plastic box... well... it works... ill make a better one with removable mesh trays or similar at a later date...

Posted

Yeah I picked up a few beakers (bomex and some kimax). I setup my distillation rig with some vodka in it, made the thermometer adaptor, and the reciever flask adaptor out of some teflon. So far it's working great, I just put a few shots of vodka in the RBF, partially submerged the flask in my 4L beaker on the hotplate with the stir bar in the beaker. The alcohol vapor is coming over at 94.5C - dunno if that's too hot or not.

 

I'll have to try the sand thing - is that just regular "play sand" or a specific mesh size?

Posted
Given the fact that it's not pure alcohol it is understandable. Pure Ethanol boils at 78 degrees C. It's actually not much more concentrated than the straight vodka. Around 45-50% according to the boiling point composition diagram.
Posted
Just made a 1/4" Aluminum BP spindel on my drill press with a file... over like the past hour... Still need a base... Like a thick flat brass plate...
Posted
Just made a 1/4" Aluminum BP spindel on my drill press with a file... over like the past hour... Still need a base... Like a thick flat brass plate...

You're right about needing a metal base. For my first set of homemade 4 oz. rocket tooling I did the same drillpress-file trick with a brass rod. I turned it with a bastard file, then smoothed it with 200 grit sandpaper, and finished it with emory cloth. I made up a set or rams from brass rod, press-fit the core mandrel into a hardwood base plate and was ready to go.....until I rammed the first motor and tried to pull the mandrel out of the motor.

 

Wrong.

 

The core came out with the motor. Back to the shop, made a baseplate out of a piece of 1/4" steel flat stock, drilled and tapped the base for the core, threaded the brass rod, and THEN I was ready to go.

 

Wrong.

 

In my pissed-off haste to get the bitch done I'd threaded the brass rod a couple of degrees off plumb so the rammers didn't line up with the core. Or, the cores in the rammers were off center. At this point my rational mind took over and I "E"-mailed Greg Boyd .

 

ASB, good luck. i hope you have more patience/skill than I.

 

The good news is that the brass rams have been cut into 1" lengths and make wonderful media in the ball mill.

Posted

Yeah i keep thinking on how im going to get it aligned just right... i havn't made the rammers yet... im thinking that since its such small tooling and itsn't going to need to take alot of pressure ill use dowel rod... Once i find a good thick piece of brass or Al plate/bar i think ill drill a straight hole through and put another piece of plate/bar underneight the hole and put the spindel base in... then drill a horizontal hole through the plate and spindel and put some kind of metal rod in in so it kinda anchors the spindel to the base... Or i could try to drill a hole verticly up through the spindel base and thread it and then try to use that with some shallow bolt to anchor it to something... I don't know... And Al is so easy to fuck up... to weak...

 

I havn't cleaned up mine with emory cloth yet, was going to but couldn't find it at the time... i tried 1000mesh wet sand paper... didn't do much at all... I might try making another spindel but from the brass bar stock i got instead.

 

 

Also...

The sieves (12) are starting to get cleaned up... i have them drying from a soakings in water/.0001% acetic acid and a soaking in water/simple green and then a washing in normal hose water... The soakings were for like multiple hours each... with the simple green one being like 4 hours or so... they will be useable...

 

Also...

Got my kevlar gloves and sleeves... can't remember if i said that or not...

Posted
Yeah i keep thinking on how im going to get it aligned just right... i havn't made the rammers yet... im thinking that since its such small tooling and itsn't going to need to take alot of pressure ill use dowel rod... Once i find a good thick piece of brass or Al plate/bar i think ill drill a straight hole through and put another piece of plate/bar underneight the hole and put the spindel base in

I think where I fucked up was the alignment of the base, which was a piece of 1/2" barstock tacked to the base plate; I don't think I cut it square so that when I tacked it, it was cocked to one side, so when I slid the tube over it it wasn't aligned with the core mandrel. I probably should have tacked on a longer piece, which would be easy to align with a square, and then cut it down to a height of 1/2" or so.

 

The other problem I had was coring the rammers. I did it on my drillpress, but I'm not too confident in my alignment of the bores.

 

Good luck.

Posted
No sporging on rec.pyrotechnics for a couple of days...
Posted
long live america....http://en.wikipedia.org/wiki/Napalm_sticks_to_kids
America is so messed up, i mean i can understand macho military marching songs to raise morale and whatnot, but thats just cruel for no good reason.
Posted

American patriots are the finest motherfuckers the world has ever know. That is just my humble opinion.

 

Have a nice day.

Posted

So what's with Red Gum? I bought it as an alcohol based binder for Ammonium Perchlorate stars, but I tried it for the first time on something else (Mess Kit willow). It didn't seem to bind at all. I used 5% Red Gum in place of 5% dextrin. I got them fairly wet; wet enough to make cut stars with denatured alcohol (50/50 ethanol/methanol), but pumped them instead. I thought the extra alcohol should ensure that the binder was activated.

 

But after drying the stars just crumble into dust as if there were no binder at all.

 

Is this one of those binders where you have to dissolve it into the alcohol and then add the solution to the rest of the mix?

Posted
It might just be the star. It binds poorly in the first place. I would suggest getting them wet enough to cut, otherwise I'd be worried about it being fully activated. It should really be sticky when fully activated.
Posted
Given the fact that it's not pure alcohol it is understandable. Pure Ethanol boils at 78 degrees C. It's actually not much more concentrated than the straight vodka. Around 45-50% according to the boiling point composition diagram.

What came over tasted fairly pure - and I stopped getting anything at all once the alcohol stopped coming over. I tasted what was left in the BF, and it tasted like vodka flavored water, under 3% if any alcohol left.

 

All in all, I'm pretty happy with this experiment, it was just a test run of my equipment before I attempt a batch of HNO3 in it.

 

Spent a while last night modifying the aspirator I bought so that it actually works - as it didn't work at all in the original state. Had to make a nozzle for the water jet, and made a faucet adaptor. Now it pulls like 25" Hg no problem. I may play with nozzle sizes a bit more, the current one is like 2.6mm.

Posted
Haha, no way, that is too funny :lol:
Posted
I was on a cinemas web site a month or so and found the same thing. Of all things though mutated sheep :lol:
Posted

I turned my poorly bound stars back into dust as I am going to try to bind them again, but used the "crumbs" from them combined with a slow batch of BP to make a 4 shot cake. 9/16" by 1-1/2" tubes were used as the shells. One of the shots broke low, but I know exactly why (mortar length in addition to a paper plug I installed).

 

Here are the results: http://www.youtube.com/watch?v=PbtkRhVFX1Y

 

As you can see, the black powder made more of a display than the stars did...

Posted
i think the stars weren't great and if you had a little more delay that would be good but the rockets looked awesome how exactly did you make them?
Posted

Thanks for the compliments.

 

They weren't rocket, but miniature shells. They were made with "m-80" casings and fired from 1/2" mortars. I basically just hot-glued plugs in either end of the m-80 casing, one end containing a little less than 1/2 inch of visco. The outside end of the fuse is cut at an angle. The inside of the casings were filled with black powder and small stars (in this case, left over fragments from my batch of mess kit willow). Then I dropped these into the loaded 1/2" mortars. These mortars were then taped to a board separated by some space and fused together with fast (yellow) visco.

 

I'm planning to do some more experimenting with cakes, since I feel that they may return quite a bit of entertainment value per the amount of effort I spend on them.

 

Plus, if a full blown shell fails, I get frustrated. But if one cake shot doesn't do what it is supposed to, it's fine because there will be many more. Only problem is there isn't enough room to do cool stuff like patterns and specific break styles in cake shots.

Posted
im still slightly confused i realize that the "payload" is a small aerial shell that is how big? but i say it looked cool cause it had a silver tail and it spiraled the whole way then spiraled and exploded but you are saying they are stickless rockets made fro an m-80 tube with no core and an aerial shell header that managed to be the same OD as the rocket?
Posted

What you see going up is the time fuses for the shells. The m-80 tube shells are shot directly out of small mortars. There is no rocket involved. I did get a prefire pic, perhaps this may clear things up:

 

http://i22.photobucket.com/albums/b330/WhyAreAllUserNamesTaken/IMG_4664.jpg

 

The shells are 9/16" outer diameter, and the mortars and 1/2" inner diameter.

 

Also, you may be able to see why the 3rd shot broke low! The mortars are secured via clear packing tape, to prevent them from tipping. Duct tape would have been my first choice, but I couldn't find any.

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