Bandsaw blades

So I accidentally broke an almost new blade on my bandsaw, and ordered a couple of new ones. In the meantime until a get the new blades was wondering if it was possible to weld the broken blade?

Is it something that can be done at a home workshop or its out of question?

Braze or silver solder the ends together. Scarf (taper) the ends on grinder then hold in a simple jig. I seem to remember one recently in MEW.

John

I’ve welded bandsaw blades fairly frequently (possibly frequently due to my technique...)

Clamp both ends of blade (just touching) on a piece of mdf. Bang a splodge of Mig weld on the join. Grind flush.

*(Checking you haven’t left a twist in the blade before welding is optional).

**(when grinding sides of blade flush, it is very easy to break the newly made join- try using sanding drum on dremel rather than angle grinder unless you have more skill than me).

Hmm, no access to torch welding... is a tig welder any good?

You can braze with TIG low current and suitable rod apparently, no personal knowledge though! Found a Utube Video it's a bit USA but gives the basics.

John

Edit: Add Link

Edited By Journeyman on 04/03/2018 15:27:31

I would guess Tig would be fine - I only tried mig when a blade snapped shortly followed by my spare, welded both and have carried on welding all my blades up whenever a blade fails now.

I’m sure scarf jointing and brazing would produce a better joint- but would potentially shorten the overall blade length- may be worth checking your adjustment limits in case...

Thanks Richard and John for you advice. Nothing to loose so I'll try to weld it first and see if it holds, if that fails will try to "braze" it, iirc the adjuster had plenty of slack to take... Good point on tig brazing John, never heared about it, but just did some reading on the subject - very interesting!

To be on the safe side you need to temper a welded blade at the weld as it may be brittle there. Colin

The only thing I'd add to the above is before you grind a scarf and silver solder a joint just check the blade over an inch or so either side of the joint - it's not unknown to find small cracks in the blade caused by twisting as the blade breaks. It's frustrating to do a beautiful silver soldered joint only to find the blade fail again half an inch away! If it is badly cracked then you might be able to shorten it but that depends on the minimum blade length you need for your machine bearing in mind the travel available on the tensioning mechanism - my Naerok bandsaw has nearly 3/4" available.

Hi Chris,

Before you do anything as this is a new blade return it to your supplier for repair or replacement.

Peter.

Sounds like a sensible move- would just bringing a couple of inches either side of the weld up to red and let cool gently be sufficient? My welds have always worked, but not for long- I suspect this could be a good solution, thanks.

Forget welding, silver solder with a small gas torch or even over the gas ring if you can support both halves. - as Journeman says. Then no need to temper after cooling etc.
BobH

Well "almost new" take it as lightly used and still a lot of life left in it (if it were not broken that is!) apart form that taking it to the supplier is out of question as it came with the bandsaw from Italy.

Will give it a try tomorrow and report back, was in the process of slicing a 65mm steel bar when it broke - should be a good test if it holds. Thanks all for your help

Industrial bandsaws have butt welders on the side for making up blades. We used to make our own blades and weld them through a hole in the job to cut the centre out.

A number of years ago I broke the blade on my metal cutting bandsaw, I need to finish a job quick so silver soldered it. I simply butted the break together with a aluminium backing strip ( ally to stop the solder from sticking ). Might of ground a v on the break & then silver soldered, still using the blade today.

ChrisB, there are a few photos in my album under 'Bandsaw blade brazing' along with a simple jig to chamfer the ends. I actually used silver solder and they hold together well. Get back if anything is not clear.

* Danny M *

I have silver soldered blades for years and don't think I have ever had a joint fail. A decent scarf joint, make up a simple jig ( u-tube has plenty of ideas ), flux the overlap and place a small strip of silver solder under the joint and heat with torch. When I heat the joint I use two of these small gas torches that produce very small (about 4mm wide )flames and place one above and one below the joint. In this way you get very good localised heating without softening too much of the adjacent blade.

Doug

Here's the very crude jig I made over ten years ago. Used for silver soldering scarfed joints and, like Doug, never had a joint fail. I flux the joint, place a very small bit if silver solder o the top and heat from underneath so that the solder is wicked through.

Russell

Edited By Russell Eberhardt on 05/03/2018 11:20:10

About 1/2 " either side of the weld should do. Temper to blue two or three times. Colin

Cheers Colin. I’ll temper this one next time the torch is out, and try silver brazing the next one to fail...