MAPP gas

[thecelticforge]

I recently began to use penny welding for things besides caulks on horse shoes. I found that I could not use penny welding in the forge for dip pans on candle holders because the work underneath would grow so hot as to burn. So, I tried to be very careful and it would still burn the metal underneath. So I finally decided to get oxy-acetylene tanks to fix this problem.
However, the "pros" at the welding shop told me that if penny welding was all I was to do, all I needed was MAPP gas. Tried it this morning and had lack luster results. After 5 minutes, a tiny section of the copper began to puddle.
So, is my only recourse to get a set of tanks like a real man, or am I doing something wrong?

Wind

[DennisG]

My two cents.....

Alot of shops up here use mapp gas for their torch needs. Some guys are skilled enough to cut 3" thickness by hand. When you got the gas did you also get O? You need to set it up as if it was an Oxy-Acet set up. For what you are doing it sounds like you need a standard tip size, set your mapp at about 5lbs and O at about 30 or so.

Hope this helps

[thecelticforge]

My two cents.....

Alot of shops up here use mapp gas for their torch needs. Some guys are skilled enough to cut 3" thickness by hand. When you got the gas did you also get O? You need to set it up as if it was an Oxy-Acet set up. For what you are doing it sounds like you need a standard tip size, set your mapp at about 5lbs and O at about 30 or so.

Hope this helps

Thanks I just bought the small canister at the hardware store. It is the one that plumbers use I am thinking. If I am going to have to get gauges and oxygen tanks, I will just go with oxy-acetylene. :)

[evfreek]

MAPP gas will work. It is pretty darn hot. Make sure you use one of those turbo type torches like a Bernzomatic JTH7. You don't need oxygen. It will help if you use brass instead of copper. Melts more easily. The metal has to be good and hot, like orange, before the braze will flow. If your candle holder has a big huge piece of metal sticking up, it is going to lose too much heat for MAPP gas to work. Are you using MAPP or propylene. I think that the latter is not as hot.

You need to isolate and confine the heat, just like for blacksmithing. In fact, you can braze brass with just a propane torch. It does get hot enough, but not if you have any kind of heat sink. Here's how I do it if I am in a pinch. Fill a soup can full of ashes, and place the big end of the part in the ashes, leaving the small end up. Sprinkle a thin layer of sand over the top of the ashes to keep the flame from blowing them all over the place. Make sure the joint is above the ashes. Then, heat and flux as normal. If you cannot get the braze hot enough (fat rod), use a small piece of brass wire from the hardware store and wrap it around the joint. Use another wire (steel) to transfer borax as it is heating up. This will require patience. I have heard of students brazing up entire bike frames this way. They use an awful lot of tricks.

Much easier to just use an oxyfuel torch, and, I suspect, cheaper in the long run if you expect to do it a lot.

[thecelticforge]

I am sure to go to oxy soon. Speaking of innovations such as your students use, I once welded with umpteen 9 volt batteries linked together. I don't recommend it however.

[Dragons lair]

Fab shop I worked at had a victor pattern burner. Ran it on oxy/mapp hotter cuts and bigger tanks.
Prefer oxy/act unless there is 2"+ to cut.
Ken

[Sukellos]

I've brazed with just plain ol' MAPP and a budget (read: NOT Turbo) torch. I used borax for flux and bits of old brass ferrules for the braze. It works! Gotta be MAPP, tho', you can't do it with propane. I was working 1/4" or smaller stock. Don't expect to braze a truck axle with this setup.

[Mainely,Bob]

One thing I had to learn the hard way was that if you try to get by working at or above the max capabilities of things you will pay for it in time and frustration.Far better to get more capacity than what you think you may need and have a reserve there if you ever need it.
My brother started with a Presto-lite plumber`s torch and then quickly went to an imported oxy/propane mini tank set when the Prest-lite wouldn`t cut it.Once he tried working with my Oxy/acet Victor torches and pro tanks he went home and sold hi set up(after kicking it a few times and calling it bad names).He now has Victor gear and rented tanks.
Minimal gear restricts you to keeping to only that level of work.Buying a couple of levels above good enough expands your abilities and horizons.

FWIW-I always start looking at the rebuilt gear rather than new when dealing with the welding supply house,most times rebuilt carries the same guarantee as new.If they don`t have it in back the rep will usually know of someone who has high quality gear at a good price who is looking to upgrade or get out of the business.
I`m one of those guys who doesn`t care how it looks,what I do care about is how it works.About the only time I buy new is when I`m getting parts to fix the old or sometimes if the job requires it and will pay for it.