Brazing with OXY/Propane

[bigbuilder]

Hi Everyone.

I havnt brazed anything is 20 plus years. I dont remember anything about it since they taught it in trade school. I am however experienced in the shop. Have my 4 stick tickets and pretty handy with a mig and a hot wrench too.

My son has a mini dirt bike gas tank I would like to braze. Its paper thin and I cant find another.

I picked up some brazing rods today. Flux coated type.

Can someone help me with the basics.....

First can I use my Victor brazing tip ( that came with my set) for oxy /propane? If I can what should the pressures be?

I apoligize in advance for my ignorance....lol.

[jpump5]

I’ve never had any luck brazing “paper thin” material.
A hole has always blown through about a millisecond after steel
reaches brazing temperature. I’ve only tried it with small welding
tips, always keeping the torch moving, to try to avoid burning through.

[bigbuilder]

Uh oh. I dont have a back up plan......

[Willie B]

What does "paper thin" mean? Is it very thin near a rust hole, or is the whole tank thin? Brazing wouldn't be my first choice to patch. You'll have to be absolutely clean inside & out. I'd favor solder, or cut in a patch & TIG it.

[tapwelder]

I have buddy said as a young welder they had to fill a 1 inch hole with braze alloy without drip for brazing cert.

Assuming you are repairing it? Cleanliness on the brazing side. Use use the side of the flame for heating, that way you can flip the torch away to control heat. Propane will heat a large area, itza bit more difficult than with acetylene. Your torch tip may be quite a ways away from the metal. Apply flux to the surface to use as a indicator. When it goes watery clear bronze should flow.

After reading WillieB's suggestion.... Plug and braze. If small enough put a screw in it.

Tank purged and clean for welding is a must. Be careful.

Tip size will determine pressures.

[smithdoor]

Victoria has charts for there tips on gas pressure

Dave

Hi Everyone.

I havnt brazed anything is 20 plus years. I dont remember anything about it since they taught it in trade school. I am however experienced in the shop. Have my 4 stick tickets and pretty handy with a mig and a hot wrench too.

My son has a mini dirt bike gas tank I would like to braze. Its paper thin and I cant find another.

I picked up some brazing rods today. Flux coated type.

Can someone help me with the basics.....

First can I use my Victor brazing tip ( that came with my set) for oxy /propane? If I can what should the pressures be?

I apoligize in advance for my ignorance....lol.

[52 Ford]

Hi Everyone.

I havnt brazed anything is 20 plus years. I dont remember anything about it since they taught it in trade school. I am however experienced in the shop. Have my 4 stick tickets and pretty handy with a mig and a hot wrench too.

My son has a mini dirt bike gas tank I would like to braze. Its paper thin and I cant find another.

I picked up some brazing rods today. Flux coated type.

Can someone help me with the basics.....

First can I use my Victor brazing tip ( that came with my set) for oxy /propane? If I can what should the pressures be?

I apoligize in advance for my ignorance....lol.

I've brazed a couple really thin, rusted through, steel tanks with MAPP or Oxy-propane. With the oxy-propane, I used a really small tip and put more heat into the rod than I normally would. I let it sorta glob onto the metal, then put the heat into that glob and make it wet out. I used Lincoln flux coated rods. 3/32" I think. Still holding years later. The MAPP torch worked too, but with that bigger flame, it was hard to control the heat.


Sent from my SAMSUNG-SM-G891A using Tapatalk

[Jax]

Same as Willie,I prefer solder on thin material. Solder melt's before metal get's near burning through. If you aren't comfortable,take it to a radiator shop and be certain to tell them it previously had gas in it.

[SweetMK]

Same as Willie,I prefer solder on thin material. Solder melt's before metal get's near burning through. If you aren't comfortable,take it to a radiator shop and be certain to tell them it previously had gas in it.

If you do not follow the radiator shop recommendation,, then,, before you start,, get something that is similar,, and

practice, Practice, PRACTICE,,,, PRACTICE!!

Without practice,, a first time leak tight braze of an old gas tank has about a 10% chance of being successful.

Practice by brazing two soup cans together,, get an old piece of steel roofing, and braze up the nail holes,,
Give it a try, you will be successful somewhere between 6 and 12 cans of soup later!!

[SuperArc]

I’ve never had any luck brazing with oxy propane.

[Insaneride]

I’ve never had any luck brazing with oxy propane.

Where do you even get brazing tips for oxy propane?

Oxy propane cutting tips are two piece and I've heard of modified rose buds but

[scsmith42]

I too have never had good results brazing with oxy propane.

Oxy-acetylene - no problem. I've brazed fairly thin (22 guage) successfully.

[Willie B]

The rusted out stuff I've repaired is never limited to only one little spot. My experience began with Jeep gas tanks. Got to resolve the volatile issues first. Then a pin hole becomes 20 pin holes very quickly. I feel it better to start from scratch sometimes, or if it's a precious restoration, cut in a patch. Steel rusted thin is not going to be a lasting repair.

[Jax]

Where do you even get brazing tips for oxy propane?

Oxy propane cutting tips are two piece and I've heard of modified rose buds but

A #0 cutting tip preform's 75% of cutting,heating and brazing in my shop. If I do more than a small job or thick cutting I will change to a mixer tip or larger cutting tip. You can find tips herehttp://www.northerntool.com/shop/tools/product_200606842_200606842
Just to clear something up. They call them welding tips but it's well known propane will not weld worth a flip.
Welding City also carry's a good selection at reasonable prices.

[tapwelder]

I have always used the same tip for acetylene and propane brazing.

[12345678910]

If you take it to an old style radiator shop, have them hot tank clean it.

They dip it in boiling lye bath.

It helps expose clean steel, it helps clean out the gas residue


I also vote for solder.

Also, go to a good parts store and get that epoxy gas tank coating kit.

It will help prevent and seal the leaks you didn't solder.

[Kelvin]

Also, go to a good parts store and get that epoxy gas tank coating kit.

It will help prevent and seal the leaks you didn't solder.

I've used this Red-Kote stuff and it worked very well, but I suspect you need to follow the instructions to the letter about getting the tank clean and DRY with acetone.

https://i.ebayimg.com/images/i/13153...-1/s-l1000.jpg

[Insaneride]

A #0 cutting tip preform's 75% of cutting,heating and brazing in my shop. If I do more than a small job or thick cutting I will change to a mixer tip or larger cutting tip. You can find tips herehttp://www.northerntool.com/shop/tools/product_200606842_200606842
Just to clear something up. They call them welding tips but it's well known propane will not weld worth a flip.
Welding City also carry's a good selection at reasonable prices.

How do you adjust the propane flame on the welding tip? Can you get a carburizing or neutral flame like with OA?
I adjust Acety for no soot and also check for flame lift off from tip. Is it the same for propane when using an OA tip?

[Insaneride]

Hi Everyone.

I havnt brazed anything is 20 plus years. I dont remember anything about it since they taught it in trade school. I am however experienced in the shop. Have my 4 stick tickets and pretty handy with a mig and a hot wrench too.

My son has a mini dirt bike gas tank I would like to braze. Its paper thin and I cant find another.

I picked up some brazing rods today. Flux coated type.

Can someone help me with the basics.....

First can I use my Victor brazing tip ( that came with my set) for oxy /propane? If I can what should the pressures be?

I apoligize in advance for my ignorance....lol.

I have a propane oxy cutting tip, two piece. Never used it. I think I will stick with oxy acetylene.

The oxy pressure for a cutting tip is around 8 times more than what's needed for a welding tip. Also , the welding tip is probably better for brazing so use it around 5psi for your VICTOR brazing tip with OA. Save your propane for BBQ. The epoxy may be better but the drip method mentioned sounds like a good idea. And maybe a heat sink.

[danielplace]

You can use a lead/tin/solder stick and fix the steel tank. Easy to buildup once you get the hang of the torch. You do not want to much or too concentrated of heat.

Air acetylene or butane even.

https://www.ebay.com/itm/36278714380...pid=1901654404

[12345678910]

I've used this Red-Kote stuff and it worked very well, but I suspect you need to follow the instructions to the letter about getting the tank clean and DRY with acetone.

https://i.ebayimg.com/images/i/13153...-1/s-l1000.jpg

Yes.

The old school rad shops do that too, but last time I bought a coated tank is was a couple hundred - that was probably twenty five years ago.

The DIY kits are at a high level of quality now, but prep and cleanliness are everything.

[farmall]

Solder is far more reliable done right than sealant which needs near perfect prep. Many a motorcycle gas tank has been rendered not worth bothering with by disbonded sealant. Customers brought us many horrors....

Before there was sealant, there was solder. Best to practice on scrap of course but I avoid sealant if I can avoid it.

Exception for patches is aircraft fuel tank sealant which every mechanic should make friends with. We grabbed all the "expired" Semkits when the Air Force threw them away instead of tracking them and in retirement I buy mine from Aircraft Spruce.

I've not found a source for aircraft fuel tank sloshing compound but haven't looked hard. That stuff is far beyond consumer sealants but would likely be more expensive than most new tanks.

[Willie B]

In my teens half the kids I knew had old Jeeps. Vermont is the center of the universe for rust. Old Jeeps had a floor under the driver's seat maybe the first year, after that the gas tank was exposed to road salt all the time.
I used to repair them with solder using an electric iron. Put some gravel in, & tie it to a cement mixer, or tractor wheel. Tumble it a while, it'd shine up the inside pretty well.
One I repaired, I had cleaned it very thoroughly. Iron wasn't making enough heat, I tried a propane torch. After an explosion stretched the 10 gallon tank to about 12, I concluded torch wasn't best to solder with.

[Jax]

[QUOTE=Insaneride;8826526]How do you adjust the propane flame on the welding tip? Can you get a carburizing or neutral flame like with OA?
I adjust Acety for no soot and also check for flame lift off from tip. Is it the same for propane when using an OA tip?[/QUO

Additional time and patience required to adjust OP flame is my biggest complaint but other benifits make propane worthwhile. Cutting tips are in higher demand so places that stock cutting tips often don't stock welding tips. Same as 2 piece cutting tip,awelding tip is recessed which make's them easy to recconize in garage sales. You must start small then go back and forth adding propane and oxygen to prevent flame snuffing out. A reccesed tip will make that proccess easier but not near easy as OA. In a breeze I often direct flame into an empty vegetable can or the like while adjusting. You can adjust for fuel rich carbonizing or neutral flame. Using an air/propane torch with large soldering copper make's it simple to fill or patch holes in thin material like gas tank above with soft solder.

[Insaneride]

[QUOTE=Jax;8828696]

How do you adjust the propane flame on the welding tip? Can you get a carburizing or neutral flame like with OA?
I adjust Acety for no soot and also check for flame lift off from tip. Is it the same for propane when using an OA tip?[/QUO

Additional time and patience required to adjust OP flame is my biggest complaint but other benifits make propane worthwhile. Cutting tips are in higher demand so places that stock cutting tips often don't stock welding tips. Same as 2 piece cutting tip,awelding tip is recessed which make's them easy to recconize in garage sales. You must start small then go back and forth adding propane and oxygen to prevent flame snuffing out. A reccesed tip will make that proccess easier but not near easy as OA. In a breeze I often direct flame into an empty vegetable can or the like while adjusting. You can adjust for fuel rich carbonizing or neutral flame. Using an air/propane torch with large soldering copper make's it simple to fill or patch holes in thin material like gas tank above with soft solder.

I knew there was a trick to adjust the flame. Thanks. I will stick to OA tho