Thread: Bandsaw Welding Advice Needed

Only three uses for a blade welder that I can think of:

Repair broken blades - questionable because whatever caused it will likely occur again.

Cut inside holes.

Buy blade stock in bulk coils (about 100 ft) for DIY assembly. Significant economy, but realized only if you use lots of blades of the same size.

If these functions have value, I'd have it re-wired; curious why it was previously wired that way.

Wiser folks can address your other questions, or augment/dispute this reply.

Joe

Thanks for the reply Joe.

Interested to hear thoughts from other members, esp how to re-rubber drive rollers.

Steve

Apparently silver soldering does a much nicer job of a join with a blade than a spot weld. It's both stronger and smoother when running through the wheels, etc.

Originally Posted by nexusone

Thanks for the reply Joe.

Interested to hear thoughts from other members, esp how to re-rubber drive rollers.

Steve

Check with one of the plastic fabrication places. It seems to be the go in the US with re belting metal cutting machines.

Grahame

If the sizes are compatible, inner or outer rings cut from auto or truck inner tubes can be used for bandsaw tyres.

If it's just a spot welder, no good at all - extra thickness will beat up the guides for a fare thee well. Tension would also be dodgy as the join goes around each wheel. Better to use a scarf joint with brazing or silver solder. I'm pretty sure I've seen a jig/fixture around here someplace, or maybe 'twas elsewhere on the 'net.

Joe

Urethane tires were what I was trying to think of in the last post.They appear to work well with metal cutting bandsaws.

I have joined metal cutting blades using flash butt welding (what you have on the side of your machine ) and with silver solder or silver brazing as it is known. A good LP torch is a suitable heat source or oxy acetylene if you have it.

Flash but butt welding is basically carried out by cutting the blade off square in the shears usually provided on the machine. Both end edges are gripped in clamps and one end is brought towards the other stationary end. The mechanism is set up to touch, create an arc and then one end is pushed into the other to fuse together.

Excess material on the blade side needs to be ground off on wheels sometimes mounted onboard the welding unit.

Trouble is that the timings on the blade weld settings can be a problem to get just right .The blades often end up brittle on the edges of the weld zone.

It can take perhaps 2 or 3 passes on the anealling setting to to overcome that brittleness.

Much less piddling about is the brazing system.

I have done a post on the technique and jigging which can be found by a search of the metalwork forum, I am just a bit crook at the time or otherwise I would list it.

Grahame

Re Rubber Wheels - Purchase rubber insertion strap from "Clark Rubber" join edges of ends with CA glue. Fix to wheel with contact cement.
Drive Belt - Purchase 10mm dia Solid Neoprene from "Clark Rubber" Cut to size and join ends with CA Glue.
Brazing Blades - Use Silver solder or brass brazing rod.
I prefer brass brazing rod and use oxy/gas to heat blade. I butt the blade ends together in a jig and then give a minute tap to just allow a hairline gap. The brass should fill the gap and just spread out on the blade.
If done correctly and with the minimum of brass rod, you may not have to dress down the weld. I do not bevel the blade as I don't want to lose blade length. I have welded the one blade many times until blunt.
I do not know how to refer a link back to my previous Bandsaw posts but if you want to trawl through you may find photo of a simple jig I made for an emergency job.

This is the jig Linden is talking about