Compressed Air Propane Torches

[catceefer]

For anyone interested, here is a picture and video of my compressed air - propane torch. I followed the dimensions given by "Ironman", although the jet is not set as far back in the throat. I need to sort out some new hoses and a connector to the compressor as it leaks badly, but I am really pleased with the overall result.

Thank you for the help.


Regards,

James.

[vtsteam]

James, seems the video is private.....?

Were you able to braze with it?

[catceefer]

The video should be public now. I have not tried brazing with it yet, mainly because the airline leaks too much to keep running for more a minute of so, but I shall try over the weekend and update this post.

James.

UPDATE
I have now. tried the torch out in practice and it brazes well. I tested it on the head of the dragon, on which my other torches only just work after a very long time heating. This new one achieves a better result within a very short period. The flame is a bit wild and I will play to see whether I can make it more focused. I may bend a sleeve up to go over the tube so that I can slide it up and down and vary the effective length.

Regards,

James.

[Orange Alpine]

I tried using a standard propane torch burner.  Covered the air holes with tape and taped it onto the torch handle for a quick and dirty test.  It gives a very nice controllable and hot flame.  Not finicky at all.

As a test, I heated a slug of steel, 7/8" diameter, 1" long with a 3/8" hole running lengthwise.  Using about 10 psi of propane and air, it rather quickly uniformally heated to a (almost) bright red.  Appears to be on a par with the Bullfinch torch.

I also tried using a rosebud burner.  Not as "nice", probably due to design differences, but considerably hotter.

It worked well enough that I'm going to make a proper adaptor and use them as my everyday source of intense heat.

Bill

[Orange Alpine]

Forgot to mention that I removed the orifice from the burners.

Bill

[vtsteam]

Not quite sure what you're describing, Orange, any pics?

[Orange Alpine]

Yes, I have pics, but for some reason the 'puter is not recognizing the camera card.

The burners/nozzles are old Turner propane torch items.  The kind that screwed onto a short, bent tube that screwed into the valve body.  I have found that the more  modern nozzles that are integrated into the tube will not work at all.   At least the Craftsman I have will not.  Also, it seems the nozzles work best when taped directly to the acetylene torch handpiece.  I bored a #5 welding tip out to .111" and screwed the nozzles onto it.  It worked and I took some pics (that I can't get out of the camers), but I'd swear the results were inferior.  More finicky and could not be pushed as hard.  More testing is in order.

Here is a link to an image of the type of propane torch I used.



(reduced image link size and embedded..vts)

[SwarfnStuff]

WOW,  that would have to be the longest link I've ever seen. It worked though and good to see what you used.
John B

[Orange Alpine]

Found a card reader that works!

Here is the torch in it's native habitat:


Nozzle modified and ready to go:


Going at full tilt:


Another nozzle, slightly different design, same size.  This one seems to work the best:


Rosebud:


New design Craftsman integrated burner.  A real lose for this application:


Did some more testing.  Connected the nozzle to the Turner pipe, then taped to the torch handle.  This gives .190" delivery pipe intead of the .111" of the welding tip.  Then taped the nozzle directly to the acetylene torch and handle.  I am convinced the direct connection gave a hotter, more controllable torch.  I think it is due to slower gas velocity.  Taping directly to the torch handle produces a small chamber, causing the gas velocity to drop, allowing more  mix to get into the burner without blowing out the flame.  But maybe not.

Bill

[Orange Alpine]

I think this is going to be my final effort.  It is the nozzle that performed best, mounted on a #5 welding tip.  The nut is a 5/16" tubing flare nut soldered on the tip.  It had to be drilled out about .040" to fit the tip.  The 5/16" flare fittings are 1/2" - 20, so I turned and threaded the Turner nozzle to match.  It all worked out good. I will probably modify the rosebud nozzle so I'll have a "big" and "little" source of heat. 

The nozzle is being pushed to its limit in this photo.



Bill

[vtsteam]

Bill, thanks for the photos. Still trying to figure out what you have. Please correct if I'm wrong anywhere here:

1.) You are using a welding torch body, and using compressed air and propane (what regulator pressures?) into that body.

2.) You are using a #5 welding tip (what brand type) to which you soldered a 5/16" long brass flare nut (drilled .040").

3.) You used a jet orifice from a Turner atmospheric propane torch, and bored (turned?) that and threaded to fit the flare threads.

4.) You taped over the atmospheric air orifices in the original torch flare.

You have something called a rosebud -- not sure if that's a different torch flare and orifice, or an actual welding rosebud for the torch body?

ps. Bill, I hope you're using torch body and tank flashback arrestors if you're experimenting like this. Too slow a flame speed along the chain of various parts can produce ignition there and or flashback. Not trying to discourage you, just makng sure you're playing it safe. Also tape isn't a good idea.

[Orange Alpine]

vtsteam

1.  Correct.  Pressures do not seem to be critical.  Currently using 8psi propane and about 20 psi air.

2.  The wleding tip size is immaterial.  I gave the tip # in an attempt to further identify the set up.  The tip has been cutoff and the thing is used as a method to connect the Turner nozzle to the acetylene torch.  The 5/16" flare nut was drilled oversize about .040".  From .320" to 359" to fit over the welding tip.  Also about 1/8" was removed from the threaded portion of the flare nut.

3.  All oricies are removed from the Turner torch.  The base of the torch is solid brass and has plenty of "meat" to be turned and threaded 1/2"- 20.

4.  Correct.

The rosebud is an outsized propane torch that I pick up from a bargain table several years ago.  It is designed and made exactly like the smaller Turner burners.  That is all I know about it.  I removed the orifice.

I am using tank flashback arrestors.  Was not aware there are similar items for use at the torch.  I agree tape is not a good idea, but I thought it was good enough for a trial run.  The nozzles run so cool under the test conditions (no heat blowback) the tape never even got soft.  But I'm going make some sleeves (maybe out of copper plumbing fittings?) and solder them on.

A couple more pictures.  First includes the rosebud to give you an idea of its size.





Bill

[vtsteam]

Thanks Bill, that clears it up for me.

Have you tried brazing anything yet w/brass filler rod? I ask, because that's the grail for me on an air/propane torch. If it can brass braze parts readily in open air, that would be a reason to make one.

[Orange Alpine]

No, I have yet to do anything worthwhile with the torch.  I have reported on almost everything I have done with it.  This idea came to me suddenly and I sort of squezed it in between other activities.

I have a fairly long and sad history with brazing, so it's not likely to happen anytime soon.  I find it strange as I am proficient with solder.  Maybe the more diffuse heat will be of benefit.

If you have propane nozzles of this configuration, give it a try.  You can lash up a test rig in pretty short order and you don't have to destroy anything.   

Bill