Friday, April 17, 2015

I managed to break a saw blade.

Yesterday I was working with the mulesaw, trying to finish the sawing of the sycamore trunk.
At some point I must have gotten a bit too eager, because suddenly I heard a loud snap followed by some clonk noises.
I immediately stopped the feed mechanism and rushed back to stop the electric motor powering the sawing mechanism.

After the flywheel had come to a halt, I could inspect the damage: The blade was broken into two pieces.

I found another blade with a different tooth pattern and finished the trunk.
The new tooth pattern works, but the surface has got a lot of texture as opposed to the old pattern that left a very smooth surface.
I guess part of the problem is that 40" is a bit too large for the saw after all.
The stroke of the saw is not so large that it can get rid of all the sawdust from the centre of the trunk, so the blade tends to bind. Unless I make a very aggressive set on the blade, but that in turn gives a less than perfect surface.

I have made most of the slabs 2.25" thick, so even with some planing, it should be possible to make a stout table.

After clearing up most of the sawdust, I stacked the slabs in the barn, so they can air dry slowly.
It is the first time I have sawed a complete trunk and stacked it this way. I think it looks fine which is good, as it will need approximately 2 years of drying time. This is based on the rule of thumb that one year will dry approximately 1" of thickness.

Asger showing the broken blade.

The stack, broken blade in front.

Asger posing with the broken saw blade on top of the stack.



  1. Oh wow, hate that blade broke but that is a nice stack of wood!! Awesome!

    1. Luckily I still have 3 blades, so there is still some years of sawing left, provided that I don't break any more.
      I am quite happy with the look of the stack of wood too :-)


  2. Hate to hear about the broken blade. The lumber looks great though.
    On the bright side...I see several knife projects in your future. Or at least several lifetimes of card scrapers. LOL


    1. Hi Greg.

      Thanks for the comment.
      I think that knives could be an option. I hadn't even thought of that.
      Card scrapers might be a bit too heavy if they were made out of that blade. I think the thickness is around 2 mm, or 3/32". But on the other hand, it could be fun to try making some heavy duty ones.

  3. Bandsa blades are welded to form a loop. Would it be possible to repair your blade?
    How are the two ends of a blade secured and how is the blade tensionned in your mill? Just curious.

  4. Hello Sylvain

    I actually considered welding the blade as a test. but I am not sure it would be strong enough.
    But on the other hand, only an experiment would show if it was true.
    I'll take a few pictures of the ends, and describe how it is mounted in the saw.
    Very simply put, it is just like a giant frame saw, that is attached to a system that will allow the saw to slide back and forth.

  5. I didn't realize how large the blades were! I have very little experience with welding, but I have to agree with you that the weld may not be strong enough to hold up to that type of sawing.

    1. Hi Bill.

      Sorry for the late reply, but we have had a stretch of semi fine weather, so I have been busy painting windows.
      My best guess for a welding would be to make a TIG weld, but I haven't got one of those machines. Another option could be to use an electrode welder and use a high tensile electrode for the job, but I still tend to think that it won't be a success. After all there is a lot of tension and stress on the blade.
      Brgds Jonas