What I have been doing (Novice endeavours with rockets)

[Baldor]

Ok, time to launch some rockets with some headers.

 

While I start learning to make cylinder shells, will an small mine work as a header? I just need to check flight path and delay time. I'm thinking of using 25mm ID tubes, very thick, 75mm long with a bentonite bottom plug. I have some tiger tail stars from last year, and some Winokur 25 that can press in small stars.

[Baldor]

 

Overkill 19mm tube support.

[justvisiting]

I have used those, but with a PVC sleeve. It looks like you have no sleeve? I hope you do! May I suggest taking every other clamp and flipping it over so that the squeezing forces are more evenly distributed? Going up the rocket, you would be going left right left right, with all the heads facing you.

[Baldor]

I have a PVC sleeve under the clamps. Machined so it fits tight when closed without a gap in the seam. The last clamp ends over the PVC, this is the reason in the image seems not to be sleeve.

[justvisiting]

When I used to use those clamps I found it helpful to put a drop of oil on the threads to reduce wear. Also, I ran tape the whole length of the clamps to keep them from sliding around when it's opened. When I used a cordless drill with a nut driver, it wore the clamps down fast! After that, I used a manual nut driver. I drilled a hole sideways through the handle and inserted a rod in the hole to give me a little more torques and make it easier on the hands. Maybe one of these tidbits could be helpful

[Baldor]

Disassembled and cleaned the entire mini lathe, halfway reassembling and adjusting. No pyro today, motor pulley broke when starting to face a plate for a mini star press.

[Simoski]

I'm going to use them for pyrotechnic, but I think they are a little too fast burning.

 

Now I'm just validating all the process, and finding the weak spots in it. I found my BP is too tame, so now i'm working in characterising it and make it faster, since it is the same BP I'm going to use for breaking. Once found what is the hottest I can do, I can always slow it for rockets, or make a batch the "old" (actual) way specifically for rockets, since seem to work well enough.

If you want slightly better BP without much work, add 2% red iron oxide, its a KNO3 decomposition catalyst and will push the thrust up by about 10%

[Baldor]

Thanks Simoski. I will try if all the other fails. Seems I get some more performance tweaking the water content. Must wait to make the TLUD to make more experiments.

[Simoski]

Do you have Jacaranda trees in Spain?

 

 

Kinda hard to miss, they make excellent charcoal for BP!

[Baldor]

We have European vines. It is what the pros use here. and very easy to obtain. It's the first I will try when I complete the tlud.

[Baldor]

19mm nozzleles core burner test:

 

 

 

BTW... What could be the average weight of a 3" shell?

[stix]

Do you have Jacaranda trees in Spain?

 

 

Kinda hard to miss, they make excellent charcoal for BP!

 

Plenty of Jacaranda trees here in Aus - never thought they would make good for charcoal.

I wonder what the little old lady next door is going to say when I start hacking into her beautiful jacaranda

[Baldor]

First fire of the tlud, with very thin pine (fruit boxes). Still have to mill it, the results seem promising.

 

Made an small batch of TT for cutting stars. I kneeded it in a bag with 40% water and let it rest to fully activate the dextrin. The result is so sticky that is impossible to make a consistent layer for cutting. It sticks to the roller. I finally put another piece of paper over it to make a consistent 6mm layer. Too much water, or too few? I will let it overnight and try to cut it tomorrow.

[Mumbles]

Too much water. I liked using waxed paper to roll out compositions. Not much sticks to it, at least nothing with aqueous binders.

[Arthur]

Typical moisture content is between 5% and 15%, but varies with compound and forming method. Less water then rested for a short time in a plastic bag is a good way of making compounds uniformly damp while having little enough water to dry reasonably quickly.

[Baldor]

I tried with 6% water on BP for screen granulating, and seems too dry. It's sitting in a bag and tomorrow will try to add very little water and work it thoroughly.

 

With the TT, first added 20% and seemed dry also. Maybe I had to work it more time. Now its in a 5mm thick layer over oven paper, if tomorrow dryes some I will cut it.

 

This is the "work" I have for this month. Learn to make stars with different methods, make usable break BP, and start making small shells. As a side project, test different woods whit the tlud.

 

BTW... Where can I find ideal tangential speeds for small star rollers?

Edited May 6, 2018 by Baldor

[Mumbles]

5-15% is too dry for anything but pressing. 15% is probably approaching the correct amount for using a loaf box. The less compression you're going to use, the more water you need. Cutting from a star patty is basically zero compression. If you're making a patty, I start at 20% and let it temper for a while. From there I adjust up from there with a spray bottle. Tempering first allows the added water to contribute basically instantly. I've never measured the actual moisture content, but I suspect it's in the 25-35% realm. The exact correct amount varies seemingly daily.

 

For me, the correct wetting for making a patty is when you can take a handful and clump it up and have it cleanly break in half. If it crumbles it's a bit too dry. If it's gooey or kind of stretches it's probably a little too wet. There might be a very slightly sheen on the surface, but you don't want much. For granulating, I go a little drier than this generally.

[Edd]

Typical moisture content is between 5% and 15%, but varies with compound and forming method. Less water then rested for a short time in a plastic bag is a good way of making compounds uniformly damp while having little enough water to dry reasonably quickly.

I really must ask, have you ever made cut stars mate?

[Baldor]

Thanks. I must make test samples of willow and some Winokur compositions, so I have plenty of opportunities to find the sweet spot.

 

I ordered some Al atomized 50um, and some magnalium 100um. I also have some flake Al of unknown size, but it is shiny and floats in the air.

 

Some suggested compositions, charcoal and KNO3 based, with this materials?

[stix]

That's plenty of chems to make some nice charcoal stars or glitters.

 

Here's a couple of comps using what you have - red iron oxide can easily be purchased from a ceramics supplier or from a hardware store.

 

 

 

 

And there's always the standard charcoal streamers:

 

 

As usual: Results May Vary

[Baldor]

Noted, Stix.

 

TT are cut and drying. Only a test batch, I plan to press or roll the stars.

 

I don't have -325 magnalium. I will have some 140 mesh that I ordered for making dragon eggs, so I could try.

 

Willow is also in the pipeline. Seems very similar to TT in composition, will see.

 

Seems D1 is perfect for the atomised Al I ordered.

 

Should investigate more into glitters.

 

This year decided to learn with only a few easy compositions, due to budget and time constraints. If I can launch with success a few 19mm rockets with cylindrical shells for the summer solstice, I will be happy. Then I will have a year to learn about other effects and colours.

 

This week I will try to make pressed stars, and make some small mines with them.

 

BTW, received the spare pulley for the late. Already up and runing, and smother than ever.

[Mumbles]

My original copy is still packed away somewhere, but I believe most Winokur glitters call for a mesh of MgAl that's basically -200 mesh. What you're getting should be just fine.

[Baldor]

 

Star plate done and working as intended. At 2500PSI the stars are a little longer than needed, so I will shave a little of the base plate.

 

Stars are Winokur 25 with 5% water.

[Simoski]

 

Plenty of Jacaranda trees here in Aus - never thought they would make good for charcoal.

I wonder what the little old lady next door is going to say when I start hacking into her beautiful jacaranda

Beats most according to :http://www.creagan.net/fireworks/charcoal_tests.html

 

Faster than Paulownia and black willow.

 

If there are Mulberry Bushes around... 8 )

 

Carefull she does not call the po po on you!

[Baldor]

Will liquid paraffin (C14H30) work as damper for BP rocket fuel instead of water? If so, what percentage? 1.5% by volume?