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luke 55
03-15-2005, 10:00 PM
I recently find an Oliver Vulcan Brazer at a trade show. It is functional but I don't know how to use it. I got some silver ribbon with it.
Thanks Luke

Rich Carlstedt
03-16-2005, 12:45 AM
Luke
i don't know about the unit you have, but generally, you twist one of the blades and then grind them on a bench grinder.Make one blade about 1/16 inch longer than the other and then grind them both at the same time. that will produce the same taper.
1.Clean with laquer thinner so no oil is present
2.Flux the blades
3. clamp the blades against the back stop.
have one clamp tight, and the other just snug.
4 Make sure the blades are short ! of completely matching the overlap ! by about 1/32 to 3 /64.
5 Place a small piece of SS in between the blades.
6. Heat the blade with a pointed tip torch till it turns med red. The flux will boila nd turn clear just before you reach this point.
The baldes will grow in length, as they are soldered, but you shortened overlap will prevent a lump and the slightly loose clamp will allow the blade to pull during the cooling cycle.
Grind the excess off or smoot with a Dremal tool grinder

luke 55
03-16-2005, 08:39 AM
The Oliver brazer is an old electric device. 110volts tranformer with two brass clamps each about 6 inch long on top of it
There's a 3 position switch low med high. With the test I've made the blades comes brittle and broke easely. Too much heat???

Jpfalt
03-16-2005, 12:36 PM
Very brittle after the solder is normal. What is needed is to temper the weld area after letting the solder joint cool to below 250 degrees F. I usually let it cool to the point that I can touch it without discomfort, about 130 deg. F. Then you heat it up until it goes just past blue temper. When done, you should be able to flex the blade both ways and the joint will bend to the same curve as the rest of the blade without snapping.

Stepside
03-16-2005, 08:46 PM
ON the electric bandsaw welders I have used you:1) Grind/file ends square 2) clamp and apply pressure 3) press the weld button 4) remove and grind weld flat on both sides 5) anneal using an anneal setting.

If there is no anneal setting try loosening and reclamping and then hold the weld button so weld area gets quite red. Then repeat so is barely red and then even less.

If properly annealed when you try to put bend in it like it would make around a wheel there should be no change of curvature. Do this without wrapping around the wheel.

[This message has been edited by Stepside (edited 03-16-2005).]