acetylene vs propane

[Paul_Guraedy]

I have used wire to support epoxy on some carvings. Now, I am planning on soldering brass rods to support my larger carvings.

Any suggestions on using brass? Size? My first project is a full size barn owl that I want leaning forward just before taking flight. Weight distribution will be to the front. I plan on extending the "leg" rod through the foot and into the base for additional support.

I know that acetylene is more expensive and burns hotter. And have been told that propane is hot enough and burns cleaner. From a carving/painting standpoint, does anyone have any advice on the advantages/disadvantages of acetylene versus propane?

[AlArchie]

Paul, if you are just soldering, propane is probably the best bet. If you plan on hard soldering (silver solder wire) you need to heat your material cherry red to melt the silver solder......small diameter stuff can still be handled with propane. You can even do light brazing with propane, but this gets a mite trickier.

I don't like to use the propane torch directly to do most soldering (short of copper plumbing), but rather use the torch to heat a copper soldering iron. I have four different sized ones. One about 1" diameter that I picked up at a garage sale and several smaller ones, down to 1/2" dia that I made up from copper rod stock. These give much better control over heat placement that the open torch.

There is a third option, that I used for a while and then abandoned as too fickle......that't the MAPP gas/oxygen system. Map gas by itself, instead of propane burns a lot hotter than propane, and with the oxygen kit allos you to do light welding. Still, that's a lot of overkill for soldering, but does better for silver soldering.

There are two types of "silver solder". One comes in a soft roll like regular wire solder, and the other is a stiff wire, welding rod like material. The soft roll type works very much like regular solder, requires only a bit more heat and is still much stonger than standard solder. The other type requires you to get the material cherry red, and results in a joint nearly as strong as a braze.

You might give some thought to one of those battery powered "instant heat" soldering tools for fine work on bird legs, although I just picked mine up and havent tried it yet......might not put out enough btu's for that type of work.

Oh, ya, about your question.......I've soldered 1/4" brass and copper rod with the large soldering iron (copper) and with an open propane flame.....no problem, either way. You might find brass tubing more appropriate for your legs, if weight is a consideration. You can work decreasing sized tubing into each other for tapering lines. Just slide the smaller tube into the larger one and sweat the joint. Makes for a nice taper and still retains the strength necessary for support.

Egads, I keep thinking of stuff......if you heat either tubing or rod red hot to silver solder, you loose a lot of the structural integrity of the material. Heating that hot ends to anneal the material, and it becomes quite soft. It can be hadened by heating to the critical temp and quenching immediately in cold water, but that's an unnessesary step if just soft soldering.

Al

[Ashbys]

Paul ,

a few simple ones

If you use actyelene, you have to have the oxygen as well , then the torch head and if you don't have these , the intional cost will be about 220.00 then you will have tank rental. If your doing a lot of brazing work the actyelene is the way to go , as the time will be greatly reduced in acheiving the result.

The propane can be completly self contained , it will take longer to heat to temp to braze , but the end result will be the same and it can be stored and purchased much eaiser.

Nothing is more of a pain then running out of acetylene or oxygen while in the middle of a job and having to wait till monday to get the tanks because it is 5:30 Friday.

[BobD]

I've done some work in the refrigeration industry, and we did a lot of soldering with just acetylene...like Al said, you've got to get the materials hot enough to melt the silver solder. But these were also copper pipes that got very hot.

I think the MAPP gas would be the best blend of convenience and speed...

Bob

[dtoggs]

Hi, may I suggest you purchase a "prestolite" soldering apparatus-can be purchased at the welding store where you buy the acelyene.
This is the standard that plumbers use for silversoldering;also the aircondition people. This outfit is light,can use a small tank and will absolutely fill the need for silversoldering,relatively inexpensive and no more experimenting. I've been using this type of outfit for 20yrs,beats the heck out of any other. JMHO pwHammer

[Thomp]

lots of optional and good information so far, just wanted to add my experiences to the bulk of the info
tinkering & knowing how to acc/oxy weld, braze and solder i have brazed brass to brass, copper to copper, copper to brass and brass to steel & copper to steel
its not a hard process to learn, but requires dark goggles so you can see whats going on when the metal sweats, and is ready to melt, but not boil, its a process done under high heat between the stages of the metal melting and running freely..

with only granulated borax laundry detergent/softener for flux which makes the fire whiter so you need them goggles.
you can even weld aluminum to aluminum with a special flux with oxy / ecc torch, with a light touch

i was understanding that mapp gas/oxy rig could just handle copper and brass brazing but there is not enough carbon-heat to torch weld steel to steel...

whitecree if you just want to get it done for a one time thing take it to a good welder or buy a set of aircraft torch set, as they call them and fill it with oxy and acetylene you can rent the tanks, to keep some immediate cost down its easy to braze 1/4th brass rods together when you got the heat and borax.. i made many room dividers and window dressings & hanging lamps out of 1/4th and 1/8th brass welding rod..

soldering is the weaker connections you can make with hot metal welding unless you make long ugly overlap joints or make/use socket welds like copper pipe joints like a fishing pole for easy disassembly to move it later

one after thought my welding supply will let you weld at the supply store for a fee, its usualy set up for welders to test new rods and such, you might look into welding booth time rental from your welding supply to keep the cost down on the occasional welding jobs you have...

[Hi_Ho_Sliver]

Having been a welder for a few years myself, I can tell you...you don't braze like metals..i.e. brass to brass...it then becomes welding....brazing is unlike metals and is a layer on top like glue.....welding is melting and fusing together like metals.....I also have the mapp gas in the small cylinder that a lot of plumbers use, its cooler than acetylene, but hotter than propane. I have in the past used propane to cut metal...takes longer because its not as hot, but is sure a lot cheaper than acetylene!

[Thomp]

i stand corrected