My FIL gave me an old vise he had laying around the shop. The movable jaw was busted off (I think he likes me but I aint sure). It had been laying in his shop for about 10-15 years. Its been sitting in my shop for about 2 years now just waiting for something the happen to it. I havent paid much attention to it until this weekend, it is a Columbia 604 M3.
Recently I have been hanging out at weldingweb and doing alot of reading on welding and such. One of the guys just did a video shoot on welding cast iron and then there was another gentleman that did a great write up on brazing and cutting. Well it all clicked in my head and I decided that now was the time to fix the old vise.
Here is the write up I did on WW.
Well it worked. I am stilll new to metal working so I dont have much in the way of a proper area for working. SO instead of kicking it old school, I was kickin it 3rd world and working on the ground.
First time using brass rods. They do flow like silver braze, its somewhere between 15% and 45% silver. It is can be thick in the puddle and it can flow easily. It will follow the flux and heat when the base is hot enough.
Prep work was done with grinder and then I used a file to take away the all the grinder marks. I did this hoping that the layer of smeared carbon and graphite left from using the grinding wheel would be removed. The new piece was flame cut from a piece of 1/2 plate I had and the all corrosin and mill scale was removed from the surfaces that would be brazed.
I am new to metal working so setup tools and jigs are something I still need to aquire. For this I used a small rectangular magnet to hold the new piece in the proper position. I then used the braze to to tack the new piece into postion. I tried using clamps but there werent any good surfaces to use that would allow the piece to sit where it needed to be.
The setup I used is the small uniweld torch with a double rosebud. Running Propane and oxygen. For intial heat my inner flame was about 1/2 to 5/8 long and neutral to carbonizing. 3/32 rods and granular flux, both hobart.
After tacking it up, I added plenty of flux to the surfaces and really started heating things up. The flux melted and flowed nicely. I started on the "ears" where the vise is its thinest. Once I got the rod to start flowing, I started walking my way across the entire piece. When I hit the heavier sections I slowed down and concentrated the heat more in a confined area, this allowed the base to heat through and melt the rod in the gap that was between the new piece and the base.
Once i was done brazing on the top side, I switched over to the face side. There was a beveled gap between the new piece and the base. I added flux and heated. Once the area was hot enough I started adding rod. I started on the far side and walked the heat and rod across the gap. Once it was full, I played the heat back and forth over the area so that It would soak in good and let the braze fill any voids I left behind
Once the intial pass was done, it was nothing more than build up after that. Build up went much faster because the "butter" layer did not need as much heat as the cast iron vise did to allow a puddle to form. I did play with the puddle and torch to see how the torch reacted with the puddle. Torch closer and bigger puddle, torch farther away and the puddle would get smaller. When the puddle was smaller it was thicker, more tike mud than water. This is the same with silver brazing, at least for me.
I am letting it cool down now. Once that is done I will break out the grinder and start shaping the braze and cleaning up the piece.
The first pic is the torch. Its made by uniweld. The heads are soft copper and they are to be bend so that you can heat from two differnt areas at the same time. These had been bent so many times that the copper had work hardened, I had to anneal them to get them somewhat straight.
Edited by coldone, April 07, 2013 - 08:11 PM.