Band saw blade welding

[garyphansen]

Does anyone have any tips for using a band saw blade welder. I bought one off E-bay and the first two blades I welded worked fine. However, the last ten I have tried have not. I am squareing the blade cuts with a miter guage on a disk sander and I am getting a good square joint, so that is not the problem. Anyone have any advice?
Gary P. Hansen

[x39]

Cleanliness is of the utmost importance. The blade material must be free of oil and dirt, as must the jaws which clamp on the blade in the welder. Clean the blade material with degreaser before welding. I sometimes clean the jaws of my welder by pulling a piece of 320 grit abrasive cloth through the jaws while lightly clamping them. Also make sure the blade material isn't slipping in the jaws as they move together.

[Herm Williams]

Hello
What type welder do you have? Are the bad welded blades the same type as your first good welded? Bi metal blades are more difficult to weld than regular blades. when you grind the blade prior to welding are you grinding the tooth back? the teeth are different metal and harder to get a good weld. Do you anneal the blade prior to grinding and after you grind? I use a model DB5, and a DB15 by Do All. according to the book the DB15 is good for up to an inch, I don't agree, I have better luck with the DB5 with anything larger the 3/4 inch.
Anyway keep asking questions there is a wealth of knowledge here.

[Evan]

Well, I snapped a bimetal blade today after only maybe 100 inches of cutting. It isn't dull yet so I will have to braze it back together. I had a spare on hand so no rush.

[ted crivea]

Check the anealing Thats the problem that i have

[wierdscience]

Annealing is usually where the problems start.Watch the color when annealing,dull red is all that's needed.When the blade goes past dull you can see the heat kind of "flow" out from the center as it goes to bright red,well when that happens you have gone to far with the annealing.

I don't bother with squaring,I just use the shear and butt the blade ends up with a 1/16" gap and weld away.

Using the same brand of blade everytime makes a difference too.

I have found that Sandvik is the easiest and most consistant to weld,while Starrett and Morse are more dificult.