Subject: Re: Band Saw Blades

From: [email-masked] (James Batson)
Date: Sun, 28 Jan 1996 12:56:18 -0600

>David C. Hufford wrote:
>
>>At the Quad State conference last September, Peter Sevin demonstated a
>>method of brasing band saw blades.  He had a clamp jig to hold the ends
>>together and brased a butt joint.  He had been doing this for some time
>>and reported it worked great.  Perhaps someone who was at that
>>demonstration (and has a better memory than I) could further explain
>>Peter's technique.
>
>Hmmm...  I have to say I am quite skeptical of the safety of this.
>If it was safe I suspect you'd see a lot more of it given that it
>is a lot simpler to  equip yourself with brazing apparatus (any
>generic torch will do) that with the specialized welding apparatus
>used in butt welding bandsaw blades.
>
>I have no doubt it can be done and that it  works but I myself
>would not feel comfortable with this method.  Bending fatigue
>is going to be more of a problem than with a welded blade.
>It would also seem that there's a greater margin for error
>in a welded joint than in a brazed one.  When brazing, the
>quality of the joinery is far more critical than in welding
>since there's no joining of the parent metals.
>
>I'd be very interested to know just how well this method
>works regarding joint integrity.
>
>        -Andy V.

Andy, there is no problem, been doing it for years.  These kits are now
being sold by mail order houses.

Cut a 1 1/1 to 2 inch section out of one leg of a piece of angle iron, 1/8
by 1 by 1 inch, which is about 6 or 8 inches long.  Clamp angle iron in a
vise with the cut out facing up on the side of the vise so thet you can
direct a flame under the slot.  You can use a straight butt joint or a
scarfed joint.  Use borax for flux and hard silver solder.  Clamp both ends
of the blade to the angle iron with two pair of vice grips.  The joint
should be in the middle of the cut out.  Make sure the blade is lined up
correctly.  Dab some wet borax on joint.  Heat joint till borax melts.
Place small amount of fluxed solder on top of joint and heat from bottom
making sure both edges are being heated at the same rate.  The solder
should flow at a dull red.  Solder flows from cold to hot.  Let the joint
cool slowly.  You should not have a brittle joint if the blade was kept
below critical temperature.  If everything was aligned and you didn't use
to much solder, the joint will require  a minimum of cleanup and be strong.

Jim

---

From: "Szucs" <[email-masked]>
Date: Mon, 29 Jan 1996 10:24:06 -0500

> being sold by mail order houses.

	OK. perhaps I'll try it some time.  Thanks.

	-Andy V.