Bi-Metal Bandsaw Blade fix

[Kevin Bennett]

This has probably been asked before but how successful is Brazing a M42 Bi-Metal Bandsaw Blade as i have 2 in good cutting condition and i do not want to throw them out. 
 
Suggestions please
 
ty Kevin

[ScroungerLee]

From what I understand you have to thin the two ends to be joined and make a half lap joint.  I have tried, using brass brazing, and it worked once, and failed numerous times before I decided it wasn't worth it.  Part of the problem is making a jig to hold the alignment perfectly.

Lee

[Goldstar31]

I've just snapped a 6x4 blade between a couple of 82 year old fingers.
For interest, I did it several times.

In the past, I have silver soldered many Starrett blades for small bandsaws- and i reckon that I can take on most silver solderers as competitors. It can be done but it probably needs annealing joints which I dont reckon that it can be done in the amateur workshop.  Obviously a professional machine can weld- and then anneal.

My contribution. Others may differ

Norman

[Kevin Bennett]

Thanks for the advice i think i will experiment on 1 of the blades  and turn the second one in to  Bi-Metal hacksaw blades cut to length &  drill holes at each end . i have just ordered 2 replacements from Tuff Saws.

Thanks for your help 

Kevin

[Goldstar31]

I think that with an element of luck that you will get a piece of metal cut- but beware, you are dealing with a rather nasty piece of spring steel - which does things when it snaps- under tension.

My silver soldering jig etc is somewhere- which is as good a place for it as I cannot remember 

[Ramon Wilson]

Hi Kevin,

Not sure how big a blade you are talking about but I have been silver soldering blades for my small Burgess bench bandsaw for a long time. It all began as the only one I had broke so it was a question of needs must and it proved successful. Through work I sourced Starrett bandsaw material in 100 ft lengths and thats I what I do all the time now.

The blade is cut to length (two marks on bench) then each end is tapered by hand on the off hand grinder. I have a small piece of steel that the blade is held in (by hand) to help present it to the wheel reasonably square. The taper aimed for - these a 1/4 wide blades BTW 14 and 24TPI - runs about 4 mm back across the full width. If they are not perfectly symetrical it doesn't matter too much as the solder usually fills any voids. I hold them across the sides of the brazing hearth with a couple of weights to keep the blades in contact. Apply flux then heat with a very small flame - I use one of those 'pencil' torches and use a minimal amount of low melting point silver solder. Once cooled (naturally) the blade each side is curved backwards and the join dressed on the grinder to give a smooth finish. If the teeth in the region are filled with solder then I grind these back too.

Sometimes they don't last very long but others seem to go on for ages. The one currently in use is now getting quite worn and is due for replacement - which probably won't happen until it breaks. They get a lot of use on various materials and have tackled stainless, titanium and 25mm thick cast iron in their time.

All that said how that would work on larger bandsaw material is an unknown quantity for me.

Hope that's of use/interest

regards - Ramon

[Kevin Bennett]

hi it is a Warco CY90 3 1/2"  1300 mm long x 12 mm 14 tpi

[Pete49]

I haven't had much luck with the bi-metal blades but the ordinary blades are no problem silver soldered
Pete