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Posted
oh ok thanks, ill post images when i make the rocket tooling
  • 4 weeks later...
Posted

Hope this is in the correct area..

 

At last, found some free time to start some stinger tooling...it's for a 3/4 " id tube... drilled and ready for a 8x32 tap. Still have to cut the base, and make a collar for drilling the fuse hole.

post-5-1162709890_thumb.jpg

Posted
sorry, the close ups are not very good.

post-5-1162710096_thumb.jpg

Posted
A few more steps done today. Both base and pin were powder coated. Base is metallic grey...pin is done in a candy clear coat, ( the colors just happen to be in the guns today )..Powder coating was picked because it doesn't spark and should be easy to release.

post-5-1163366690_thumb.jpg

Posted
base

post-5-1163368761_thumb.jpg

  • 1 month later...
Posted

I recently got a lathe and want to make some rocket tools.

Im looking for 8oz and 1lb rocket tooling kit dimensions. That would include the length and diameter of the spindle/nozzle hole. As well as drift length diameter etc. Stainless steel is so hard to machine so i was sondering if bronze,brass,or aluminum can be used? I've been vieing pictures like these http://www.pyrotooling.com/images/BP/BPset_assy.JPG and am very confused about the holes in the drifts. Maybe a brief overview of how rockets are pressed would help me understand. I am very new to this hobby of rocketry so please don't flame me.

Posted

The holes are simple. It is so the core can fit inside. Pressing a solid rammer into the core pin, well the core pin probably wont fair too well. You can't use just a solid rammer because you need to use increments in order to keep the fuel grain relatively consistant. Too large of an increment and you get a density gradient, and it will probably cato.

 

Overview of pressing:

 

Add increment of clay, press with the longest rammer.

Add increment of fuel mix, press with the longest rammer

Continue until the change groove stays above the top of the tube.

Add increment, and use the 2nd longest rammer.

Continue until the change groove stays above the top of the tube.

Add increment, and use the 3rd longest rammer.

Continue until the change groove stays above the top of the tube.

Make sure the fuel is above the top of the core pin, or the next increment will be above it.

Add increment, and use the solid rammer.

Continue until all increments added.

Posted

You could also try buying a small kit like a 4oz size if you have a little money. It's the same principle loading a 4oz as loading a 6lb'er. And it's really hard to explain about the spindles and rammers by writing it down (Mumbles did a fair job at it though). Actually loading one yourself will explain the process much better. Don't get me wrong, all I'm saying is you learn better by doing, than by reading.

 

And yes you can use Brass or Aluminum for the rammers, although for the spindle itself I think I would stick to Stainless, it's harder and will stand up better to all that ramming. If you screw up a rammer, it's faster to machine a new one of those than a spindle.

Posted
What keeps the whole from filling with fuel. That would make it impossible for the spindle to get inside. Thanks for all the great info though.
Posted
The spindle does actually. It fills the hole so comp cant. Some does get in there, so you do need to clean it out from time to time. However, it's not bad enough that the spidle won't fit all the way down.
Posted
What keeps the whole from filling with fuel. That would make it impossible for the spindle to get inside. Thanks for all the great info though.

Some composition does in fact get up in the rammer, but it isn't bad. What I've done is taken 2 brass rods, one is a 1/16"OD and the other is a 3/16"OD. I cut these to about 9" long and on each I filed the ends down. One side has a sharp point, and the other just has a 45deg angle on it. I use these rods (whichever size works best on a particular rammer) to scrape the composition out of the inside of the rammer.

 

Loading BP rockets, I've never had to use them, but I do have to use them when I press whistle rockets.

 

You want your rammers to be free of any packed-in composition before ramming the next increment.

Posted
What should i use for nozzles and plugs. I mean which clay should i use? Do i just add it dry?
Posted
Buy the cheapest kitty litter you can find, and just use that dry. Some people add a small bit of graphite and/or wax as well.
Posted
I recently got a lathe and want to make some rocket tools.

Im looking for 8oz and 1lb rocket tooling kit dimensions. That would include the length and diameter of the spindle/nozzle hole. As well as drift length diameter etc. Stainless steel is so hard to machine so i was sondering if bronze,brass,or aluminum can be used? I've been vieing pictures like these http://www.pyrotooling.com/images/BP/BPset_assy.JPG and am very confused about the holes in the drifts. Maybe a brief overview of how rockets are pressed would help me understand. I am very new to this hobby of rocketry so please don't flame me.

Here are some pics of the tooling I have made to build 3/8" ID 4" long core burning rocket motors with nozzles.

http://i107.photobucket.com/albums/m314/di...07/S3010728.jpg

http://i107.photobucket.com/albums/m314/di...07/S3010692.jpg

http://i107.photobucket.com/albums/m314/di...07/S3010735.jpg

I use brass for the spindles and rammers. It's easy to machine and will not spark when ramming motors with a hammer. The base that holds the spindle is aluminum with a hole drilled in it the same diameter as the lower end of the spindle. The cross hole in the end of the spindle is so you can put a nail or drill bit through it to add leverage when twisting the spindle out of the core. I cut a 30 degree bevel at the base of the spindle taper to form the lower angle of the nozzle. The hollow rammers are easy. Just center drill them with a diameter that is a close tolerance to the lower end of the spindle taper. The important thing is that the center hole is deep enough that the spindle won't hit the bottom of it. I got the ideas for making my tooling by looking at pyro tooling sites posted on the web. Anyway I hope I helped you out. keep working on it and you will end up with something like this.

http://s107.photobucket.com/albums/m314/di...=Picture061.flv

  • 1 month later...
Posted

My rocket pressing tool set for 2 different size casings:

http://i111.photobucket.com/albums/n155/markx_01/IMG_0415.jpg

 

The nozzle cone and core former:

 

http://i111.photobucket.com/albums/n155/markx_01/IMG_0417.jpg

 

I find there is no need to ball mill or powder the bentonite, as the pellet form in which kitty litter usually comes works even better than a fine clay powder. The pellets are driven into the casing walls like a coarse sandpaper and become impossible to dislodge:

http://i111.photobucket.com/albums/n155/markx_01/IMG_0419.jpg

 

The finished bentonite nozzle formed by pressing the kitty litter pellets shown in the last picture.

I use sodium waterglass solution as a binder and add a controlled amount of it to the pellets right before they are pressed. The waterglass acts as a strong binder and glue enhancing the nozzles resistance to erosion and blow out even further. The finished nozzle is rock hard like ceramic enamel and cannot be scratched even with a screwdriver:

http://i111.photobucket.com/albums/n155/markx_01/IMG_0418.jpg

http://i111.photobucket.com/albums/n155/markx_01/IMG_0421.jpg

http://i111.photobucket.com/albums/n155/markx_01/IMG_0420.jpg

Posted

I've tried both catsand, bentonite and are moving into some fine (not dust) charmotte I just purchased at my local supplier.

I saw this post and got curious about the "sodium waterglass" binder.

Can someone enligthen me on the subject, and other names, as well as its original purpose? I

'll try to find some, but first I have to know what I am looking for...

Posted
I've tried both catsand, bentonite and are moving into some fine (not dust) charmotte I just purchased at my local supplier.

I saw this post and got curious about the "sodium waterglass" binder.

Can someone enligthen me on the subject, and other names, as well as its original purpose? I

'll try to find some, but first I have to know what I am looking for...

Well, waterglass is sodium or potassium silicate in solution. Mainly it's used to make things fire resistant (i know of no other use). Any hardware store or paint shop will carry bottles of the stuff. It's not expensive, set me back for 3$ for a litre, and this goes a long way.

Posted
It's sold as a sealant in some cases, such as in ceramics. I do believe an outer layer of the stuff is placed over the glaze in some cases to add a seal. It may actually be a common componenet in glazes. The heating in the kiln would melt it and give the shiny appearance. Long story short, look at ceramic suppliers. It's pretty cheap stuff.
Posted
I've tried both catsand, bentonite and are moving into some fine (not dust) charmotte I just purchased at my local supplier.

I saw this post and got curious about the "sodium waterglass" binder.

Can someone enligthen me on the subject, and other names, as well as its original purpose? I

'll try to find some, but first I have to know what I am looking for...

Well, waterglass is sodium or potassium silicate in solution. Mainly it's used to make things fire resistant (i know of no other use). Any hardware store or paint shop will carry bottles of the stuff. It's not expensive, set me back for 3$ for a litre, and this goes a long way.

It was also used once to coat the outside of a spherical report which was then dipped in sawdust. I believe the color was red, cherry red.

Posted

Thank you all for the info. As for looking for it in a ceramic supply, thats actually where I get a lot of my metals and salts from, as well as my clay.... I'll try my best:

 

I've read that waterglass comes in solution as well as in prilled form. I might be a bit slow off the mark, but will I be looking for the liquid stuff? In that case, will the nozzle and plugs not shrink when drying?

 

I'll give it a go, I know my cermamic supplier has some, and I'll have a look in some of the hardwareshops around.

 

I see from some datasheets that some of these solutons also contains kaolin and quarts, but that won't hurt I guess.

Posted

It was once used as an egg preservative I do believe and yes you're looking for the liquid form.

 

You can also use it to make Silica gel, those little drying packets that come in electronics and stuff. I'm not sure how, but that's what I've heard.

Posted

So today I got hold of some "Waterglass", not very har to find when you know what you are looking for... :P

 

I lightly moistened my bentonite/charmotte mixture and started working. It came together quite easy actually and with the waterglass, the clay is easyer to handle due to less dust. It compacts easy as well.

 

The nozzle is not as "pleasing to the eye" as straight bentonite, a bit more nicks and burrs, but that might be my newly made tooling as well.

 

As for strength I'm not sure as they are not fully dried yet, they seem harder but also a bit more brittle.

 

I'll see how they work, made 49 in total, so I really hope it will be worth the effort..

  • 2 weeks later...
Posted

O.K so I decided to try building a rocket motor to lift larger payloads. Say 100 to 125 gram headers. I came up with this tooling to make 15mm ID 130mm long motors. :D This is the largest one I've made so far.

http://i107.photobucket.com/albums/m314/di.../Picture077.jpg

I just finished ramming the first one and the tooling works flawlessly.

http://i107.photobucket.com/albums/m314/di.../Picture078.jpg

http://i107.photobucket.com/albums/m314/di.../Picture080.jpg

So far I have built tooling to produce four different sized motors.

http://i107.photobucket.com/albums/m314/di.../Picture081.jpg

From right to left. 5mm ID by 55mm long bottle rocket. 10mm ID by 100mm small skyrocket. 12mm ID by 100mm small skyrocket and the latest 15mm ID by 130mm medium skyrocket. These are my own classifications since my tooling isn't built to "standard" tube sizes.Surprisingly it seems easier to ram the larger motors than the smaller ones. Now on to the next step, building the shell for the header.

:D

Posted

Moonshot: Have you static-fired your 15 mm?

I tried two 15 mm ID motors today, and they both blew the top (and one end) plug.

I am using 60:30:10 (approx) and a 80 mm long 6 mm dia spindle, a tolal casing length of 100 mm.

I will probably come around to mage the casing a bit thicker and mage me a sleeve as well.

Posted
No I haven't tested one yet. The pic is of the first one I made. My spindle is 4mm at the base and 85mm long. Not much taper to it. I'm using 71kno3, 24 coal and 5 sulfur milled and grained for propellant. I have to test the bigger motor to see how it performs and make any adjustments to optimize the performance. I'm thinking to open the nozzle ID to 5mm. One thing I learned from building smaller BP motors is that you don't want to change the nozzle ID much if your using the same speed powder even though your ramming a larger tube, unless your making the spindle longer. I have my 10 and 12mm ID 100mm long motors dialed in. They are very reliable to lift 35-45 gram headers but I want a motor that will lift 2-3" shells. I will try to get a video of the test flight of the larger motor and post it. I am going to a big party soon so I might shoot it there. :D If your just blowing out end plugs and nozzles but not splitting your tubes the tube should be strong enough. you might try shortening your spindle to 65-70mm.
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