How do you weld bandsaw blades

We just bought a spool of band saw blade stock and we want to cut it in sections and weld blades. How do we weld them so that they hold up?

Reply to
Ignoramus16559
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There are 2 ways . You can cut a bevel arross the thickness and silversolder them or you can build or buy a resistance welder (similar to a spot welder) that fuses the ends together under compression . And here's a link to one made by Ernie Liemkuhler that uses a TIG welder to fuse the ends.

Reply to
Terry Coombs

"Ignoramus16559" wrote in message news: snipped-for-privacy@giganews.com...

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Hold the two ends together, one atop the other, with the teeth facing in opposite directions, and grind the ends straight and even. Freehand is fine, the angle across doesn't have to be 90 degrees because if the blade edges are held parallel when ground their 'supplementary' angles will add to 180 degrees.

Clamp the ends in the welder and set the energy level for the blade width. Weld, then anneal the joint.

Grind down the welding flash on either side only enough that it doesn't foul the guides. Run the grind scratches lengthwise so they don't concentrate tension stress.

The grinding wheel should be dressed straight. I prefer a pedestal grinder to do the ends, though the little one on some blade welders is more convenient to remove the flash.

Folding them into three smaller loops:

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I couldn't preview it with my XP, IE8 and dialup.

The 1-1/4" x 16' blades for my sawmill are a real challenge to fold. I unfold them by throwing them onto the lawn.

--jsw

Reply to
Jim Wilkins

Spring for the blade welder, you won't regret it.

Reply to
Tom Gardner

I've seen several at machine shop auctions but they always went for more than I could justify..

--jsw

Reply to
Jim Wilkins

Is your spool bi-metal or single material? If a single material, there are lots of welders which clamp the two blade ends to large electrodes, and when you hit the button, the ends are slammed together while a lot of current is pulsed through them to melt them into one piece. There is typically a grinder mounted in the same thing to remove welding flash so it will pass through the guides properly. You also have an "anneal" button, which puts a lower current through the joined ends (it gets at least to red, and you give in successively shorter pulses so it cools slowly.)

However -- many of these don't put enough current to handle the bi-metal blades (an edge of HSS welded onto the main backing and that takes more current to weld the HSS part. Usually it will work as long as your blade is a width or two below the maximum for the welder.

Another approach is to take the two ends, grind a shallow angle onto each so they partially overlap, and then use a torch to join them with silver solder. I've read (here) from people who made their own jigs to both hold the blades to grind the same angle on both, and to hold them together for the Silver Soldering.

If you have a big vertical bandsaw (and *you* likely do), those often have a blade welder mounted in the left column, so you may already have that -- it is just a matter of learning to use it. One reason for that is so you can cut a (good) blade, thread it through a hole drilled in a workpiece, weld it back together, thread it back into the bandsaw, and use it to cut out a hole which does not reach the outer edge of the workpiece.

Enjoy, DoN.

Reply to
DoN. Nichols

Ig can justify it.

Reply to
Tom Gardner

I am eyeing one right now

Reply to
Ignoramus26011

Be aware that blade welders are rated for the maximum blade width they are capable of welding. It would be wise to purchase a welder with extra capacity. Avoid the china blade welders.

Best Regards. Tom.

Reply to
Howard Beel

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