11 replies to this topic

[BIOHAZARD]

Hi-
I made some fountains, roman candles etc. and made some BP rockets but they were crap because I used a screwdriver to punch a hole in the end-so would it be better if I drilled a hole straight down?
and when you've pressed the BP in your rocket and pressed the clay plug on-is it safe to use a metal drill to drill a hole for the fuse?
Thanks

[rocket]

Yeah its fine to use a drill bit to drill into rocket and alike, just take it nice and slow and clean the bit every now and then wile drilling so it doesn’t get hot. Though I cant see that happen if you take it slow.

[Wyvern]

Id just like to add make sure that there is no metal powders in the part you are drilling as it could result in a spark even if you do it slowly

[Pretty green flames]

Id just like to add make sure that there is no metal powders in the part you are drilling as it could result in a spark even if you do it slowly

Also remeber, if you are using grog in your clay mix you should not drill into it because grog can spark.

[BIOHAZARD]

Thanks again everyone

[dr thrust]

drilling rockets! get your hand in your pocket and buy some tooling! if your serious about pyro, cheapest isnt always best ..ps 200 posts, so there!

Edited by chris m, 21 August 2007 - 05:01 PM.

[Richard H]

Does not sound like the best idea to me. Far safer to use a spindle and a hollow rammer set. If you are using a remotely operated CNC drill or propellent lathe then fine, otherwise I would not recommend this course of action!

[Arthur Brown]

My ex-Woomera friend used to describe TNT as an engineering material with which you could do machine shop operations EXCEPT you couldn't drill it.

So better to make the hole some other way.

Best to get tooling that forms the grain core and motor nozzle as you load the tube

There is science in the nozzle design and the grain core.

[dr thrust]

hi got a pyro book today by kentish and he talks about useing a "shell bit"! anyone?

[icarus]

if you are really short of tools you can make excellent wooden rammers by shaping the wood as it turns in an electric drill chuck with sand paper ive reverted to all wood rammers separate set for bp etc lathe turned Having safely remote rammed the rocket from base upwards how do other people deal with pass fire hole??? i confess i drill small rockets with long extension arm on pillar drill but the big ones have to be rammed nozzle up then i cant ram a bentonite nozzle as the tapered hole in my fuel grain is too wide i dampen my large cases then tie a tie wrap close to one end ideally wet with sodium silicate solution the cold cast nozzle of fire cement cant blow out as the case end lips in slightly but have to dry them out before firing anyone any better ideas ??????

[TheExplosionist]

Why not drill the hole first, then add the composition to the device?
Ironically I find it very difficult to light these things. I gave up trying to light my one and only rocket ever to light last year after trying loose powder and nichrome wire to no avail.

[icarus]

the passfire hole is 2mm the composition is rammed with a conical depression to increase burn rate as larger area of burning comp conical hole 8mm wide nozzle diameter 3.5 mm bp should fire from visco ok but solid fuel block ie sugar/kno3 require igniters they are hot cast into case totally different build method to bp