1" Black powder

[davidg]

I wa gifted a 1" BP tool set from Woody's. It looks great. Only tried to make a couple using 60:30:10 and they CATO'ed. Still fun though. Trouble is supporting the tubes and achieving 4,500psi is not that easy with plastic tubing. The tubes buckle too easily. I will have to get a metal support and keep on trying.
Just have to get over carpal tunnel surgery and Christmas!

[Pyro-Gear]

Nice gift, Dave have you thought about using brass shim stock as a support as shown by David F it works great, there is a video kicking around he posted up on you tube.

Good luck with Christmas and the surgery.

[sambo]

good luck mate,

I'll have a look in the store and see if i have a spare 1" Firesmith Collette support, I know I have 2 in 3/4" but I can't remember if I have a spare in 1" if it's any use. But as Ken says, the brass shim stock looks to work a treat.

and wax dem tubes.

[Boophoenix]

Dave, can ya share more about the tubes you're using and the charcoal? I've made a few 60/30/10 smaller rockets and can't seem to Cato one even breaking most of the rules of pressing, ramming, and increment sizes. Are you using nozzles if so and it's a core burner which I suspect it is leave the nozle out and try.

DaveF has done some awesome rockets with the brass shim stock so I'll second Ken's suggestion. You might try one or two backing off the preasure if ya notice the tube starting to deform and wrinkle. My smaller rockets will survive minor tube wrinkling.

I actual saw my first live Cato on a trip with Caleb ( Woody's ) earlier in the year close enough to be personal. It was a whistle with a lampare header broken with whistle. He makes sme really nice 6 pound whistle to stobes too.

[davidg]

Hi Ken,thanks for the good wishes. I am struggling to find shim stock of the right size. I have found one supplier and am waiting for a reply.

Sambo,that would be great if you have one.

Boo,the tubes are spiral wound. I think they came from OB here. I will be rolling some myself when I can so that will eliminate(I hope) that as an issue. The charcoal I use for rocket fuel is a pine. I mill the fuel for 15mins in one of Ken's mills then I add mineral oil to the mix. The tubes were waxed but even backing off to 1500psi,the damn things still buckle a bit. That is the main issue as the walls buckle,the pressure of the gasses does the rest. I must admit I had not considered nozzleless though. I will try that after the stitches are out. Thanks guys.

[Boophoenix]

You mentioned a straight BP formula indictating no metals are present. If ya can since ya mentioned the surgery I'm not sure you'll be able to hand ramming one might get ya over the hurdle.

The only remaining things are the tubes you've covered. Otherwise I'd have to lean towards increment sizes since you have not mentioned those. The other things you've mentioned should darn near give you a hundred percent success with decent tubes and proper increments. My first were willow charcoal no additives nor wax. Those two addatives should prove to allow some of the hottest propellent combinations when things align properly. I've recently heard some guys do just have trouble with certain styles of rockets while they excell at others though.

Image of the spent tubes if enough is remaining may could give some clues too.

Keep in mind though while not an active builder of rockets I have followed lots of information on them so take my advice with a grain of salt. There may be a gap or two in there, but I'm fairly certain to my knowledge offered ya sound input,

You'll get'r figured out though. Those that delve to deep into rockets seem to enter a dark side so I keep my distance to keep a varied path of investigation of the art. If ya try to record it a hope ya have much better luck than my first airborn rocket video. I caught a puff of lingering smoke. The visco I grabbed was a little fast than I thought and it launched and was gone before I ever looked up from lighting it.

Speaking of ignition sources there are a couple of variables there too. If you're trying to ignite further up the core move the ignition source towards the nozzle to slow the propagation of the core ignition slightly. Sometimes it seems the nozzle can get restricted by some ignition sources I do believe.

If those all fail add an additional 5% coarse charcoal till ya get success.

[Pyro-Gear]

Well one dam good post by Brad well done I can’t fault it well done Brad.

Dave when we run OB we never supplied 1/inch tubes AFAIK, but I think I know where you got them from the only thing they are good for is shot tubes (in a word crap) not good for rockets if you are pressing them, however I could find some parallel wound tubes for you.

[sambo]

Spiral wound is no good ! you need parallel wound tubes.

[davidg]

Well one dam good post by Brad well done I can’t fault it well done Brad.

Dave when we run OB we never supplied 1/inch tubes AFAIK, but I think I know where you got them from the only thing they are good for is shot tubes (in a word crap) not good for rockets if you are pressing them, however I could find some parallel wound tubes for you.

I agree Ken. Good post there.
As for the tubes,they are rubbish. I will try my own first when I can,thanks Ken. I have a tube roller that is nearly finished.

[Boophoenix]

Lol, thank ya fellas. I've read a lot and then some. Even though I don't retain what I read well discussing it forces me to think about and forms better memories. Hence a little of my arm chair pyroing. Some other things were in play in that as well that were safety issues I didn't like, but I've about corrected all of those. If the weather doesn't get to crazy this winter I may have to get some of the backlog of projects going. Maybe by spring I can get the charcoal research started too.

Sambo, that's a little of a broad statement if you're speaking spiral in general. I've always had good luck with spiral tubes from Phil's store here in the US. I do have a decent selection for me of smaller sized NEPT's stashed away from before they closed and reopened though.

Steve Laduke and Caleb both had fair luck wth them running them to the limits as a little challenge between them. I do believe Caleb started having some troubles a few months back, but he has those with NEPT's some times too. Calebs rockets normally do one of two things they'll fly or they'll Cato. He doesn't have much middle of the road, lol.

Caleb and DaveF may call tonight. We sometimes conference call to pick at each other. Which made for a very long and funny night on election night. If they do I'll see if I can get Dave to swing threw and leave some feedback. With all of his rocket testing in the last couple of years and current screen mixed BP research he's done some neat things that some may not have seen unless you've visited Fireworking or APC.

[sambo]

Brad, that's an interesting point you make, it's so useful to hear of other experiences. I've never been successful at making anything with much power using spiral wound tubes.

Dave, can we see your tube roller ! ? !

[Boophoenix]

Sambo, for general rockets I think they've had good luck. They are supporting them and do get right on the line of what they can take. I forget right off what those pressing forces were. They didn't rival those of NEPT tubes though. If you ask either today what they think they'll give ya a medium rating as I'd bet both of those guys moved back to the ragged edge of what the tubes can take. That's why they like rockets though to push the envelope I think.

It all comes down to how hot you want your rocket or what you're trying to lift. DaveF tinkered around and hit the point of deminished returns by getting his BP propelant to hot while the rocket survived. He's a tinkerer of ideas and concepts like many here. Those tinkering lead to some interesting findings some times.

[sambo]

yes, I must admit, I've become stuck with what works for me, I guess I should get the ACME stand back out and experiment some more, mostly at the moment I just shoot waxed NEPT tubes ( WITH A NOZZLE ) and 75:15:10 + 1% mineral oil, although some of the charcoal in that mix is 80 mesh and I don't ball mill just rice. That'll get most of what i need up !

I have some Oliver Brown 3/4 inch spiral tubes that'll work on 60:30:10 screened and riced but I tend to just turn them into mortars for stars now.

[Pyro-Gear]

Make the most those old OB tubes Sam as there are none left in the country, tubes will be a big issue for the old imperial tooling for the foreseeable future I for one won’t be reordering, the minimum is 10,000 and I can't justify the investment.

NEPT tubes well there great but after shipping the cost is astronomical, so maybe Dave has the right idea roll your own, you lot have had it to good

[davidg]

Brad, that's an interesting point you make, it's so useful to hear of other experiences. I've never been successful at making anything with much power using spiral wound tubes.

Dave, can we see your tube roller ! ? !

I had some pretty good results with the 3/4" OB spiral tubes and an aluminium support. Lifted 3" shells with no problem.
As soon as it is finished,I will upload some photos and a description of the construction. I have a different method than the one already seen. I have based it on my textile experience.

[Boophoenix]

Ken, the NEPT's are a bit costly in my opinion anyway before they travel across the pond. I've never used any of my stash of NEPT's yet for that very reason. Maybe Phil could work up something to cover the void if the tooling is common over there?

Dave, I'd enjoy any information you're willing to share. I find I can't find enough of that when it comes to pyro.

[Dave F]

Nowadays I use waxed tubes and waxed BP propellant. Whatever the propellant is, I add 2% of the batch weight of paraffin wax. I dissolve it in naphtha first. The wax doesn't dissolve easily in cold naphtha. I melt the wax in a can, remove from the heat, and add the naphtha, about 400-500ml per kilo. The wax is worked in with gloved hands. If the powder is a little too dry to granulate through a 12 mesh screen, a bit more cold naphtha can be added and worked in. With waxed tubes and propellant, you can really push the limits with black powder rockets. Here are a couple of links to rockets I made this way:
https://www.youtube.com/watch?v=v1iqwBI8Lfk
https://www.youtube.com/watch?v=aBSWfsuZikM
These rockets are 26mm ID nozzleless, made on extra-long BP spindles. The motors are 30cm long.

[Boophoenix]

Good to see ya visiting the friends across the pond again Dave. Thanks for sharing.

[sambo]

Thanks for sharing those Dave, absolutely loved them, especially the second one. What ratios do you use on your 1inch coreburners ?

[Boophoenix]

Sambo, I do believe all of Dave's rockets these days are 75/15/10 plus additional paraffin wax.

[Dave F]

Yes, mostly 75-15-10 ballmilled for propellant. The delay was Lancaster's yellow glitter minus the dextrin, granulated with 2% wax- just like the propellant. With a lighter heading on such a rocket, I press less propellant and more glitter.

For the first rocket, I wanted the charcoal tail to match the burst. That propellant had 10% coarse charcoal mixed in with the ball milled stuff before granulating with wax and naphtha. You can see how much that 10% takes from the power!

[sambo]

[quote="Dave F"You can see how much that 10% takes from the power![/quote]

yes, you sure can, I haven't run anything that hot over 3/4 inch so that's well worth knowing. I add mine in at around 80 mesh, I'm guessing yours is similar. Have you ever tried nitrating that coarse charcoal, by that I mean soaking in a saturated solution of KNO3 then rapidly drying.... ?

[Boophoenix]

Oh Sambo, Dave's got a pretty laundry list of rocket experiments all the way to a fuel hot enough he got deminished returns according to the Acme test stand if I'm stating that correctly. He's done quite a bit of one off testing and experimenting that it's been an honor to follow along with. Even when we clash on ideas every now and again, lol.