Up untill now I have been forging with propane and a little charcoal here and there. I picked up some coal a while ago and used it for the first time today. I had the fire going and decided to try some forge welding. I used 3/8" round bar and just tried some loop welds.

My first try I burnt the end almost right off. Second try went well, it stuck:D!! Third one went even better.

I figured I would try it in my propane forge. I have heard that it is hard to weld in a single burner, but wanted to find out for myself. I did 2 loop welds with propane and both turned out quite well, I am extatic!!!

The first 2 pictures are my second and third try with the coal. The last pictures are of the welds in my propane forge.

Feedback and criticism are more than welcome!!

Good for you. Your first forge weld is a moment you won't forget.

Nice job on your first attempt

Those look like nice welds - well done.

I see a little crack at the toe of the scarf. For me that indicates that the toe was too thick going into the scarf.
As the end (very tip) of the scarf is in line with the blows applied (top and bottom) it is not in a welding plane.
When the surface is going in the same direction a
as the blows, it is in a shear plane - not a welding plane.

I hope that this makes sense to you.

Nice job with your welds!

Mark:

How do you correct for that?

Thanks,

Frosty

Mark:

How do you correct for that?

Thanks,

Frosty

For me, it's a question of thinning down the toe of the scarf. If the end of the toe is thin, then it will soon be turned and forged into the bar. It is when the end is thick that it acts as a shear, cutting the metal (forming the crack ) rather than blending in.

I hope these two photos show the problem and the fix.
The graphic shows the result of a thick end to the toe (visable crack). The photo shows the fix - thin the toe before going into the weld.

I hope that I am explaining this OK.

Edited February 13, 200917 yr by Mark Aspery
Meaning & clarity (ish)

I didn't understand post#4 but this is very clear.
Thanks ,I may try to forge weld.

Thanks mark, I was wondering about that, I thought I left it a little thick. I am happy for my first try, but now I can improve more. Thanks again!

Mr. Aspery,
that explains some of the problems I have had, thank you! It never occurred to me that the shearing was taking place. As I am a picture kinda guy, the diagram was most helpful. I'm really looking forward to seeing you at GLIIF.

Mark, do you not in this case put a little edge on each tip so as to dig in or bury itself in the mating bar so as not to burn in the fire...like when we made the flux spoons in class.

Mark,

What type of flux do you use?

Thanks

Chris

Mark, do you not in this case put a little edge on each tip so as to dig in or bury itself in the mating bar so as not to burn in the fire...like when we made the flux spoons in class.

Not in this case Jim,
With the flux spoon, the little bend on the end was to allow a gap between the two surfaces in the (faggot) weld-but allow the toe (tip) of the scarf to touch the larger parent stock.

In touching, the parent stock acts as a heat sink to the toe of the scarf, preventing it from burning in the fire.

With the lap weld (drop tong) there is no heat sink available (2 separate pieces) - the smith has to be a little more careful in the fire to prevent burning the toe of the scarf. Thus no need for the little bend at the end.

I do place the scarf with the toe up in the fire for most of my welding heat as I feel that the piece heats from the back first - this I feel protects the toe somewhat. As I hope you see - this is a hypothesis with no scientific evidence to support it.

Mark,

What type of flux do you use?

Thanks

Chris

I use Anhydrous Borax. I get this from a local knife maker.

I don't think that there are any 'Super-fluxes' out there. Pick one and then get to know it ...well!

thanks for clearing that up

Mark,

Thank you. I just thought I saw you say in another thread you didnt use 20 mule team but something else.

Awesome job !!!
Those look cleaner than my first ones for sure.
And cool little loopy twisty thingy there too ;-)

20 mule team borax has I think something like 20plus% water in it anhydrous borax, as the name implies, has all the water cooked out and re ground it does not look the same it is not a powder ..here is a link of a good place to buy some Knife Making Supplies