Need info on a good oxy/acteylene set up for brazing

[bulgie]

Another option that avoids repetitive re-lighting is a torch with the gasaver built-in. One is the Smith "Lite-O-Matic" AW6. I have never used or even seen one, not sure how hard they are to find, probably "very".



At one shop where I worked in the '80s, we used some Euro torches, sorry I forget the brand, but they had the gasaver function built in too. Flip the switch to Off and the flame goes out, except for a small candle-sized pilot flame, still coming out of your torch. I loved those torches, but finding one today might be near-impossible, anyone know?

Obviously you have to find somewhere to hang the torch where the pilot flame doesn't lick against anything flammable! Most torches don't have a good way to hang them, so I add a simple hook held on with a hose-clamp. Useful even if you don't have a gasaver. Paul Brodie, a youtuber, makes a fancy hook for his torch in this video, but it seems like too much work to end up with something that isn't really better than my bent rod and hose-clamp. Maybe I would do it too though, if I needed content for a youtube channel? (Not roasting Paul, he's a great guy.)

 

[helmbelly]

I love my "gas miser" aka gas saver or gasaver,

Wow, I love this! It's like an old 1920's telephone hook. Is Lilly Tomlin in your shop patching your hoses into the tanks wearing a hair net?
Also love the didjridu player in the BG. I gotta re-read all this. O man I looked at a Meco Midget - very nice and very spendy too. I just can't belive they made a telephone cradle for a brazing torch. wow

 

[helmbelly]

"Watson come quick!" I didn't just invent electricity but feel like I did. I just got a successful strong braze between my 316 and 304 SS. These are pieces kludged together to experiment on getting the silver to run. Cleaned on a scotchbrite wheel. I'll try to get a usable part next. Thanks guys

 

[helmbelly]

So the test shots above are a 5/16 stud ground off at an angle to roughly mate with the tube- so solid to solid, maybe sorta touching. The actual pieces I need to make are a stud piercing the tube with a few thou clearance - so air gap. Starting to think this has been complicating things so far. Also probable that I don't know what I'm doing yet and am over thinking the hell out this. Need to grind my brain off at a 45 degree angle to roughly mate with a 6 string guitar and forget about this ****e! Happy Friday fellow backyard engineers!

 

[helmbelly]

I love my "gas miser" aka gas saver or gasaver, which is a switch you hang the torch on. The weight of the torch pulls the lever down, shutting off both lines to the torch, but it leaves the torch valves open and perfectly adjusted. It also supplies a small "pilot light", a little air-acetylene flame that's there ready to light your torch when you pick it back up. Saves a lot of time re-lighting and readjusting the flame, perfect for repetitive work where you have to set up a part, braze it, and turn the flame off while you set up the mext one.

I actually have two of them, total luxury for a home hobbyist, but I grew to like them when I used them in production, so I had to have them for my home shop. I have one each on my acetylene rig and my propane rig.

If this sounds sketchy to you, safety-wise, well I guess it has its potential catastrophe waiting to strike, but in the 50 years I've been using one I don't remember a single scare. You just have to remember to turn everything off before you walk away. The pilot flame is there to remind you, which helps.

The two I have are

(1) a Smith, like this:
View attachment 469041

Still made, I think, though this one is from the '70s

...and (2), a really old "Harris Calorific", don't know how old but it appears in the 1929 catalog, and may have already been an old item at that time.

View attachment 469042

Since I mostly work on small stuff, I like the small aircraft torches like the Smith AW1A (well mine is actually an AW1, the precursor to the AW1A) and Meco Midget. As you can see I also like the Ultralight hoses from Tin Man Tech. The small torch and ultralight hose increases dexterity and precision, decreases fatigue. I don't braze all day like I used to, but I'm old and weak now. I can't hardly stand the weight and stiffness of those "red/green" welding hoses anymore, I'm spoiled. If you get ultralight hoses though, try to suspend them from the ceiling so they come down to you, not laying on the floor, because they don't hold up to being walked on, or having blobs of molten metal fall on them. Most people daisy-chain them with heavier hose so only the last bit to the torch is ultralight.

But I digress! If you get a gas-saver and you use propane, be aware they make a pilot light specific to propane. The flame tends to blow out if you use propane with the fitting made for acetylene. It's a 2-minute job to switch the pilot light piece. I switch mine back and forth sometimes, though I mostly stick with propane these days.

I love both these photos but the first one - oh man, it's basically a knife switch cut off- or a guillotine gas switch. Elegant stuff and the stand had to come with it right? if that's been jigateered - hats off. Nice to see these photos- my envy level is 30,000 feet. Good old american engineering. In bottom photo (Harris Calorific) do I see thread seal on those threads? I want to dope up all my threads by I read somewhere that's a baddie with gas.

 

[helmbelly]

(Not roasting Paul, he's a great guy.)

No I'm pretty sure Paul just got roasted ;-o

 

[bulgie]

So the test shots above are a 5/16 stud ground off at an angle to roughly mate with the tube- so solid to solid, maybe sorta touching. The actual pieces I need to make are a stud piercing the tube with a few thou clearance - so air gap. Starting to think this has been complicating things so far. Also probable that I don't know what I'm doing yet and am over thinking the hell out this. Need to grind my brain off at a 45 degree angle to roughly mate with a 6 string guitar and forget about this ****e! Happy Friday fellow backyard engineers!

Silver doesn't like gaps, strength drops off a cliff when the gaps get over a few thousandths. Would you consider brass brazing them? Brass fills gaps well, but doesn't like to wet out on stainless, so you'd have to make the handle out of plain steel (or alloy like 4130 if you need the strength). It takes a different flux, but brass flux is better at lifting oxides and other contaminants, so brass brazing is a lot less demanding of cleanliness. (Note, what I call brass is called bronze by the welding industry. Don't get me started! But I'm right and they're wrong! Just shop for bronze filler rod and they'll send you proper brass.)

Some people seem to like flux-coated rods and/or powder flux but not me, I only use paste flux. The stuff they'll sell you at the LWS is probably sub-par, so I'd get some "Type B" flux from GasFlux Company. You can get your filler rod from them too. I like their C-04. Huh, I just noticed they say C-04 can be used on stainless — never tried it, maybe I should. I don't remember if gasflux.com has minimum order sizes that are unfriendly to hobbyists, but if so you can get small amounts of their stuff from Framebuilder Supply.

Another option is the rod misleadingly named nickel-silver — which has zero silver in it. It's a bit higher-temperature than brass (opposite of silver) but it sticks to SS, and it's super strong. The filler itself is about as strong as mild steel. It can use the same flux as for brass, but Cycle Design sells a flux specially formulated for nickel-silver. Their website doesn't look like much, but they're a reputable company, I like their filler and fluxes and they've given me excellent service.

 

[f350ca]

Another option that avoids repetitive re-lighting is a torch with the gasaver built-in. One is the Smith "Lite-O-Matic" AW6. I have never used or even seen one, not sure how hard they are to find, probably "very".

View attachment 469045

At one shop where I worked in the '80s, we used some Euro torches, sorry I forget the brand, but they had the gasaver function built in too. Flip the switch to Off and the flame goes out, except for a small candle-sized pilot flame, still coming out of your torch. I loved those torches, but finding one today might be near-impossible, anyone know?

Obviously you have to find somewhere to hang the torch where the pilot flame doesn't lick against anything flammable! Most torches don't have a good way to hang them, so I add a simple hook held on with a hose-clamp. Useful even if you don't have a gasaver. Paul Brodie, a youtuber, makes a fancy hook for his torch in this video, but it seems like too much work to end up with something that isn't really better than my bent rod and hose-clamp. Maybe I would do it too though, if I needed content for a youtube channel? (Not roasting Paul, he's a great guy.)

Was given one years ago, hooked it up to try it but have never really used it. Neat little torch.

Greg

 

[bulgie]

I love both these photos but the first one - oh man, it's basically a knife switch cut off- or a guillotine gas switch. Elegant stuff and the stand had to come with it right?

I don't know what you mean by a knife switch or guillotine. It has spring-loaded valves that are open ("on") unless the weight of the torch pulls the lever down. The stand was made by me in about 30 minutes, from qty 4 of 2 ft long, 1/2" (ID) plumbing pipe, and a 3-way 90° elbow that I tapped another hole in, for the pipe that goes up. You need to have a tap for 1/2" pipe-taper threads. Put threaded caps on the three legs facing down, and a "floor flange" on top, which the gasaver bolts to. I also added a 10 lb weight that was free at a neighbor's yard sale, for extra stability, but it was pretty stable without the weight.

 

[bulgie]

do I see thread seal on those threads? I want to dope up all my threads by I read somewhere that's a baddie with gas.

No sealer needed, they're designed to seal without it.
Sometimes I'll use some tape, like putting gauges on a regulator, but only the special tape made for oxygen (usually green colored) is allowed on an O2 line. Regular teflon plumber's tape can spontaneously combust in the presence of pure O2.

That's my understanding anyway, I don't claim to be an expert.