Propane VS. Mapp Gas for copper Brazing.

[Bill of the 45th]

Anyone know what the Temp difference is between Propane and Mapp gas in a torch.  Can it be done with just your basic propane torch, or would it be better for me to get Mapp.  Second if I go to Mapp do I need to get a new Head with tip, or will the Propane one work, ie. interchangeable?  Getting ready to braze a southern butt plate.  Does anyone rivet them first?

Bill

[George F.]

The Mapp gas IS hotter by a few hundred  degrees. And I use the same tip.   ...Geo.

[Daryl]

The older propane tips put out a pencil flame that is quite quiet - kinda fsssssssssssssssssssssssssssssssss, while a Mapp Gas nozzle throws a wider flame and 'blows' more like a hard, high oxy. flame from an oxyacetylene torch.  Mapp isn't as hot as oxy/acet but it's a good deal hotter than propane.  If you use a propane bottle with a Mapp nozzle, you'll get much hotter propane temp.  The Mapp nozzles have ports back near the valve to let in air to mix with the gas before it ignites.  prpane tips pull in some air just behind the tip, but present it right at the end, providing for a quieter, small point of flame.  We use Proplane with Mapp nozzles for general small-part silver brazing (silver soldering), whereas larger jobs of 1/2" diameter can be silver brazed with Mapp quite easily- or you can use your brother's oxyacetylene tanks 'n hoses. 

[Carper]

Mr.Knapp:  I always rivet the buttplate as well as the triggerguard prior to brazing them. As a matter of fact I look for the rivet when I first pick up a rifle with what looks like "homemade" parts., sort of like a belly button. A few things to consider if this is your first one.  1. Get the fit as close as you can, dont have to be perfect but dont try to fill in too much gap. 2. Use a copper wire instead of a brass rod. It will look better when you brown the furniture.3. Be carfeful with the heat, when you have the parts right they wont be very thick and it can blister and burn in just a few seconds, I cant tell you the number of pieces that I ruined brazing mild steel in the forge.  The little torch sets that you can buy in dept stores with the little orange oxygen tank and using propane for around  75.00  will do a great job but the oxygen will run out real quick.( might do half  dozen sets) and  that little flame is easier for the first time person to control. I have even soft soldered some together that are still doing fine, with the rivet.  Good Luck and remember the worst forging beat the best casting.  Or so I heard.   Johnny

[Steve Bookout]

Bill, get the Mapp gas.  Bookie

[Ken G]

Maybe I'v got the wrong set ups but I have not been able to braze with Mapp or propane or the two combined.  I bought one of those little Mapp / Oxy set ups.  That works great for me. 
I rivet parts first.  If brazing I use steel rivets.  If soldering I will use copper rivets. 

[JCKelly]

Copper wire melts at 1981F. For the stuff to flow in brazing, one needs a higher temperature. Commercial copper brazing is done at a process temperature of 2050F.
Agree, a copper braze line will look better & more traditional than brass. Process has been around for some time. I have an old Italian wheellock, lock only, with parts copper brazed on.

[Rolf]

JCKell,
2050F is welding temp. for steel. If you have to get it that hot , why braze instead of forge welding?

Best regards

Rolfkt

[northmn]

I have a Mapp gas torch, but it was recommended for Mapp.  It would probably work with propane, but I thought that a propane torch was not neccessarily a Mapp torch.  I have done considerable brassing with a Mapp torch using 3/32 inch braze rod.  It works on small items such as front sights, or in one case putting a sling attachment on a upper thimble.  Should work for a buttplate.  Mapp also works better for hardening small metal parts like a frizzen.  I rarely use propane anymore, but sometimes for small soldering jobs the lesser heat of propane is a little easier to control.

DP