brazing continuious saw blades

[tackit]

New here first time posting. Thanks MIller, you proven once again your a welder friendly company.

I am limited to single phase power, I have the MM 251, SD180 and Challenger 172. The Challenger 172 really kicks butt, I love that machine.

Question:

Guys I have two 10'X 1" continuos blades that have small bad spots in them. I am thinking about using one blade to repair the other.

I was wondering if anyone here has done this and if so could you please offer some directions and tips. Thanks

[karish]

tackit,

I noticed you asked about brazing the blades, which leads me to believe you have an OA set up. Let me say first that I am no old hand at this, but I have made continuous bandsaw blades from rolls of stock. Silver solder was used, and the high quality solder is definately worth the price. One roll will do many (perhaps all you will ever do) blades. The set up was to bevel both ends at about a 45 degree angle so they overlap a bit, make some manner of clamp or jig to hold them in place, and solder them. Works good, last long time. Of course, if you know someone with a blade welder, or a saw with a weld built in, you can save some time that way.

[tackit]

Karish, I thought silver brazing would work, I just needed confirmation from some one who has actually done it, thanks for you help and interest, I really appreciate it Karish.

[idjeffp]

Karish,
Hah! I had a good friend with your last name that moved to North Pole, AK years back after we all got laid off! So the big Q is ...Are you one in the same? :-)

Jeff P
Boise, ID

[karish]

Jeff,

Yes, I am. Are you still with HP? I can tell you I don't miss our old location or employer at all.

How did you get into welding?

John

[idjeffp]

John,
So good to connect with you again!!! To answer your Q...TIG welding 1018 and 4140 steels is of great interest to me these days :-)

I think of the times we spent out at the LC range every once in a while. Email me at [email protected] and we can take this offline.
jp

[illuzion]

When you Tig repair a bandsaw blade, how do you prep the blade? Is it just a 90deg cut, or 45deg? Do you overlap the segments, or just but them together, and do you use filler metal at all?
-illuzion

[karish]

The way I was taught, and did it in the welding classes was taper each side 45 degrees or 30 degrees on each side so you get some overlap without adding thickness to the blade. We made improvised jigs using fire bricks, scap metal, anything we could find to hold the two sides in place and used a silver solder for filler. I seem to remember it being 85% silver. I'm by no means an expert (hardly knowledgable really) on all the alloys of solder available. The up shot is, a second term student was able to silver solder some blades together, and they held up. In fact, we never had one break. Wore the teeth off a few, but never had a joint give up the ghost.

If you have some small sections from an old broken blade practice it a few times. It's actually kind of fun. Hope this helps.

[karish]

Never mind!

Okay, so I was a little distracted. The minor detail of "TiG welding a blade" went right through the ol' knoggin. Sorry. I've never TiG'd a blade. I would think that you would just use a 90 degree joint and butt weld.