Gas welding

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Red Dwarf

Gas welding

Post by Red Dwarf »

Here's a pic of my third gas weld. This one actually failed the hammer test, but it looks much better than the previous two (which actually did PASS the hammer test, but looked horrible).

Next step is to get them looking good and strong too. I think a tubing notcher is the key because right now it is too hard to get the joints to fit tight. Seems a good fit is the key to a good bead

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Red Dwarf

Post by Red Dwarf »

BTW, the rod used is coat hanger. Anybody else use em?
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c chardt
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Post by c chardt »

it's a start got to learn some time
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Post by ricmey1 »

Buy flux coated brazing rod and you will see a big improvement on your welds. Dont overheat the joint just heat the bottom of the rod with it resting on your joint and let it just melt quickly. If you keep heating the joint it only makes it worse, because you try to add more rod. Less is better! When we welded my cage it took about 3 to 4 seconds to do each wire weld. Two other hints, TURN the torch down.... it shouldn't make any noise when your flame is right. It only takes a small flame, also for big gaps lay the rod sidways with the joint and melt it enough to just stick, then melt the rod over the joint normally. This is how I did it!!!
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gator
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gas welding

Post by gator »

Flux coated 1/8 brass rod. Very, very small flame. Just enuf to heat joint and maintain heat as y'all advance the weld. Try to use a small 4" side grinder to help shape the joints. Practice makes perfect.
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Post by marshmaster pat »

That gas welding is a disappearing art. Nothing I do with a brazing rod is very pretty, but it holds.

This site is not exactly the same topic, but has some neat advice and some of the best gas aluminum welding that is probably done these days. It is worth the time to look.

http://www.tinmantech.com/
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Post by cowboy »

Red,
All the above is good advise.
Heat the weld joint till both sides are JUST cherry. If the tube starts to crackle, your oxygen is too high. Re-adjust. Bring the rod tip just into the flame, and get it hot. Keep it in there, and it will be ready to tough down on the work right when your ready for more.

Lay down some filler, and advance down the joint.

Turn your torch down the weld, so the flame is running off of the filler metal bead as you progress. If the flame stays on the filler you put down, it will just stay puddled, and run / drip. This will let you develop a nice bead.

If your filling a big gap, don't be afraid to stop for a moment. This will let the filler cool, and you can start a small pudle on the edge again. Just takes a few seconds.

Small Brazing tip, small flame, and small flux coated rod. All this makes it easier to control. You can go bigger heat after you get better. I'm still running small stuff myself. Hope your wearing some cutting / welding goggles. Staring at that puddle will hurt your eyes after a while. I aint no expert, but these considerations work for me.

Keep at it, and you'll develop your technique. You will also find that the brazing rod is stronger than most of the parent metals you'll use it on.
Red Dwarf

Post by Red Dwarf »

So the general concensus is brazing is superior to welding for this. For some reason I like the idea of welding. Maybe it is just that I am not familiar with brazing.

Cowboy, I have my oxygen and acetylene both set at 4 PSIG and a very small, traingle shaped flame kernel with no sound (neutral). It seems to work quite well. All I have ever done is stick welding and I cannot believe how much control you can have over the puddle with gas!

And yes I am using my goggles. I did try some without them, but man it's just too bright 8)
Red Dwarf

Post by Red Dwarf »

Wow, brazing is quite simple and fast. I am now convinced this is the way to go. Here's a little piece I made, my first exercise in brazing. Almost looks better than any weld I ever made

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Post by Sniper »

Red Dwarf

I have been a FAA certified welder for 27 years and I think you are on the right track with the brazing rod it is quick and easy and it holds up well to vibration if you clean your joints well and practice you will be amazed on how clean and neat the weld joint will be and if it ever breaks it is easy to fix.
Red Dwarf

Post by Red Dwarf »

Yeah Sniper, I have been very careful to remove the zinc from the joint area and clean them with brake cleaner before starting.

I have also been practicing tight fitting. That will become much easier when my new tubing notcher gets here 8)
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Post by c chardt »

looks good. I always said practice makes perfect
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Red Dwarf

Post by Red Dwarf »

Yeah, I still need practice, my beads are not consistent yet, and there's some spots in those joints that didn't get completely filled (you can still see just a hint of the joint).

My hands are naturally kind of shaky, but I do get better with practice.
Red Dwarf

Post by Red Dwarf »

Image

Little work I did today. Brazing is a lot stronger than I used to think, and I'm not even that good at it yet!
Red Dwarf

Post by Red Dwarf »

Finally figured out that 1/2" EMT is not measured outside. O.D. is more like .700" so a 3/4" hole saw works pretty decent for notching it. Tested the notcher out today.

My grass rake will be done this week if the hurricanes will hold off
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Post by c chardt »

what are you building your motor stand out of
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Red Dwarf

Post by Red Dwarf »

Motor stand will be 1" square tubing and 1/4" plate. I'm not taking any chances there.
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Re: Gas welding

Post by Cubman »

Is bronze rod the same as brass rod? Or do I need to keep looking for brazing rod that says "brass" on the package?
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Re: Gas welding

Post by terrible ted »

The pictures don't show on my pc. I don't do much with the torches. I like to see a vid of how the flam should be by the pros. I may be running to hot to.
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Re:

Post by dougeey »

Red Dwarf wrote:BTW, the rod used is coat hanger. Anybody else use em?
Get some stuff called seven mule boraxs it will work as flux for the coat hanger
Doug
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Re: Re:

Post by skinnypockets »

dougeey wrote:
Red Dwarf wrote:BTW, the rod used is coat hanger. Anybody else use em?
Get some stuff called seven mule boraxs it will work as flux for the coat hanger
Doug
Years ago we used coat hangers and borax for gas welding. I have also used copper, (electric wire). Worked pretty good but not as easy as brass. I was thinking there were 21 mules in the borax so I asked Mr. Google for his opinion. Turns out there is only 20 mules in borax. Doug, looks like we're both getting senile!

Well I figured that Mr. Google must be a pretty smart feller so I asked him about the bronze / brass thing. That really gets complicated, it looks like braising rods can be made up of a combination of many different alloys depending on what you're wanting to braise. Here is a sample;
http://www.sarusilver.com/brass-bronze- ... lloys.html

Think I'll just stick with the flux coated brass rods! :banghead:
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Re: Gas welding

Post by John Fenner »

Great description of brazing guys, same as I do it, but real hot flame aimed right at the filler rod, the residual heat gets tube hot enough to hyperbraze.
Squeeze tube ends then trim with tin snips to fit angles etc. where any coping joints are needed, no hole saw needed.
I never finish anyth,,,.
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Re: Re:

Post by dougeey »

skinnypockets wrote:
dougeey wrote:
Red Dwarf wrote:BTW, the rod used is coat hanger. Anybody else use em?
Get some stuff called seven mule boraxs it will work as flux for the coat hanger
Doug
Years ago we used coat hangers and borax for gas welding. I have also used copper, (electric wire). Worked pretty good but not as easy as brass. I was thinking there were 21 mules in the borax so I asked Mr. Google for his opinion. Turns out there is only 20 mules in borax. Doug, looks like we're both getting senile!

Well I figured that Mr. Google must be a pretty smart feller so I asked him about the bronze / brass thing. That really gets complicated, it looks like braising rods can be made up of a combination of many different alloys depending on what you're wanting to braise. Here is a sample;
http://www.sarusilver.com/brass-bronze- ... lloys.html

We were poor could only feed seven mules :lol: but I still use it for brazing and gas Welding
Doug
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Re: Gas welding

Post by Gary S »

I go to the welding supply store and say I need brazing rods.
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