Catherine Wheels
#1
Posted 24 April 2003 - 12:04 PM
I have made some using some waxed paper straws filled with 65:15:10 + Al.
Cellotaped them up, added some backing card with a hole for the fence nail and tried them out.
Not too bad - had to be given a push to start going but they looked great!
However, they occasionally stopped - not good - do I need to use some sort of rocket nozzle or is there an internal spindle that's needed?
Any better ideas for their manufacture?
Cheers
#2
Posted 24 April 2003 - 01:02 PM
Hope i didnt lose you in any of that. I will take a picture of one i made and put it on here to give you a better idea.
[Edited on 24-4-2003 by Pyromaster2003]
#3
Posted 24 April 2003 - 01:20 PM
Try Lancasters pin wheel composition:
Meal and grain gunpowder: 74
Potassium nitrate : 13
Sulphur : 13
For silver wheels add 12 % bright aluminium.
All parts are % by weight.
Good luck! Maybe try and get some pictures of your wonderous wheels!
Also, pinwheels never have nozzles or a spindle, they just use a high thrust composition with a high % of blackpowder.
[Edited on 24-4-2003 by Richard H]
#4
Posted 25 April 2003 - 12:16 AM
One of the easiest "wheels" is to just strap drivers(end burning rocket motor)
onto an old bicycle wheel. You'll have to make a bracket but that's a rather simple affair. I make the bracket out of some flat
steel 1/8"thick,maybe 2" wide and approx 8-10" long. Imagine a flat pc of steel on a table. When bent for said bracket it should
look roughly like the profile of a hat.The brim of the hat needs a couple of holes bored into it on each end so it can be attached to the upright. When screwed to
the upright there should be a flat hump large enough to access the nut from the bicycle axle. A hole needs to be bored into the center of this hump to accept the
axle.
** note*** to pyromaster...your right , it ain't easy to descibe some of this stuff.
The idea is to mount in some manner an old bike wheel to an upright. Over here we use iron wire to fasten the effects to
the wheel at a couple of points along the length of the driver.
For the sake of clarity.....a driver is made in the same manner as a trad. bp rocket ie
it has a nozzle. The difference is there is no core. I have made tooling for myself ranging in sizes from 3/8"-1" for constructing these devices. There is no reason you could not ram a clay bung in a good tube(watch your selves boys) and then very carefully at slow speeds bore a hole in the center of this clay plug to form a nozzle. Be certain that the first 13mm or so does not have any thing that might spark off your drill bit. Use common sense here. It looks like a ESTES rocket motor when completed.
The difference is that it is designed to be pretty via charcoal effects etc. Thrust is almost a secondary concern. A bike wheel spins pretty easy.
High RPMs do not always make a pretty wheel. Experiment.
One driver comp. I use gives me a burn time of 16 sec. Good RPMs. Another comp. I use gives me about 57 sec. Give or take.
Not so good RPMs. use both together and ........you get the idea. The possibilities are endless. There are guys over in Malta that have got this wheel gig
so figured out it would make your head spin. Pun intended. I can barely describe how to bend a pc of flat steel. I am not even gonna attempt to describe what these guys do. Pics don't even do it justice
They make these incredibly complex wheels out of stuff you could find in a junk drawer. Seen it myself. Not in Malta.
The club shipped a couple of guys over and they did some demos.
Willing to post some driver formulas if any one is interested. They are not the only ones out there. Lancaster has good
formulas of course. Variations can be endless. Nozzle dia. can of course effect thrust etc.
One bit of advice on the nozzle. Make it as deep as it is wide. If the i.d. of your tube is 10mm then make the length / depth of your nozzle 10mm.
ABOVE ALL ELSE BE SAFE.
This is fun stuff. Yes you can harm/ kill yourself making even these kind of devices. Make small ones first. Less risk and less composition used in the learning process.
Boy, that one sure was wordy.
[Edited on 25-4-2003 by bernie briden]
#5
Posted 25 April 2003 - 12:29 AM
the straws. Your going to have to make yourself some paper tubes Rhodri. Here's how.....first get some.....
#6
Posted 25 April 2003 - 11:49 AM
Essays of information!
Will start off with a Lancaster comp. with Al, and smallish 3" wheels.
I'd like to try the bike wheel too.....
Watch this space.....I'll put up some photos soon.
[Edited on 25-4-2003 by Rhodri]
#7
Posted 25 April 2003 - 08:56 PM
#8
Posted 26 April 2003 - 01:11 AM
device. Place device in hole with nozzle end up. Fuse. Light. Observe in relative safety. If it goes nuke on you at least it's in the dirt.
Not very exciting but good for testing.
Well consolidated driver compositions have less gaps. This means less explosions.Ramming comp in smallish increments helps to. Make a LOT of notes
and keep them forever.
#9
Posted 26 April 2003 - 08:05 AM
#10
Posted 26 April 2003 - 10:17 AM
Bernie, funnily enough I do actually test comps. and the like in a deep plant pot filled with compost! Great minds eh?
I check out fast burning Willow BP's that I'm going to use for lift - just to check that the compression doesn't burst the tube.
Some of the Willow BP I've made - after wetting, balling then re-wetting etc. is surprisingly fast burning - not news to you guys I know - but I find that with the right care and attention to detail - and time of course - I've made BP that's 'better' in both 'whoomph' and 'light' than some of the professional granualted powders from salvaged pyros.....anyway - I'm wandering off course here.
OK, I'll apply the 'dirt pot' to the drivers too.
The advice of a notebook is invaluable - and I totally agree. I've made a few notes about comps. etc. and do have a rather 'messy (covered in charcoal and the like) book - a copy is something I don't have - cheers Rob! I shall photocopy away.....
Looks like it may be sunny later today - might start building up some wheels.....
[Edited on 26-4-2003 by Rhodri]
[Edited on 26-4-2003 by Rhodri]
[Edited on 26-4-2003 by Rhodri]
#11
Posted 26 April 2003 - 12:47 PM
Did not mean to infere you were not being thorough. As usual I was babbling on.
Do you have access to titanium? I like it a
quite a bit in my bp driver comps etc.
[Edited on 26-4-2003 by bernie briden]
#12
Posted 26 April 2003 - 02:25 PM
No problem! I REALLY appreciate any and ALL information on pyros. - you weren't interfering - please send more tips and tricks!
Ti - no I don't have a ready source. AL, Fe, CuO, Mg (shavings) is all I currently have.
In a way it makes it a little more challenging using basic metals - when you get a good result it's all the better!
Once I've got the drivers sorted I'll experiment with the comps. I quite fancy a red and green driver with some Al.
I'm new to colour comps. Rob et al have provided me with much good material on how to make good colours/stars - Mg stars for example - loads to be getting on with.
It's turned out quite sunny down here in Southampton so I'm off to build some pyros.
First going to make Lancaster's comp.....speak to you in a bit.....
Rhod
[Edited on 26-4-2003 by Rhodri]
#13
Posted 26 April 2003 - 07:40 PM
My favorite effects have always been
charcoal effects. Charcoal just always seems so elegant. It's cheap to. Depends of course on the application etc. etc.
#14
Posted 26 May 2003 - 09:15 PM
#15
Posted 04 October 2005 - 07:20 PM
This is a 60cm wheel with two drivers one dragon egg fountain and a whistle.
The drivers were made out of 1lb rocket tubes, as was the dragon eggs fountain. The whistle tube didn't work. Why I'm not sure. I have never failed with a whistle before, but at the same time this was the first time I tested salicylate.
It rotated for about 30 seconds. But I would like it to be a little faster next time.
The driveres used a 66:25:9 mix with 3-4% additional very coarse Al fales used in fire fly compositions. The firefly effect were very nice, but a little to annonymous. Next time I'll use more Al and more KNO3 to give it more speed and sparks.
The dragon eggs, with primer comp., were Bi(III)O based and charged in the tube with no choke.
Here is a movie: PM me
I cut the movie so the one in the link is a few second in the end. When the dragon egges stop popping, you can see the firelfy effect sepparated fron exploding eggs, for a fraction of a second.
Edited by Yugen-biki, 09 November 2005 - 05:22 PM.
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