Thread: Blade joining (again)

Originally Posted by Fossil

Hi all,

I have purchased about 500' of blade from USA. I should be here next week. I haven't braze joined blade before, so read up on all the posts I could find here. I have made up a nice jig, and decided to repair an old HS tipped blade that I have in the workshop. I have scalfed the join, and beveled edge etc, but both times I have joined the blade, the join has failed. I am no mug at silver soldering, having done a heap of plumbing work over my time.
I used 2% stick of plumbers silver solder. Is this the problem or is the steel used with tipped blades not suitable for soldering???

Just to clarify.... I don't have any problem soldering, having done heaps in the past, so cleanliness, flux, correct heat etc, have all been good.

Thanks for any advice.

Fossil

I'm not sure, Fossil, but I would have thought that you would need a higher silver bearing or content than 2%. There's a hell of a lot of stress on a bandsaw blade joint.

Buzz

Fossil, for what it is worth, the Australian Woodsmith, No 70 has a couple of pages on "Brazing band saw blades" and it refers to a brazing supply kit sold by Carba-Tec. This kit includes solder - and though it doesn't give the percentage of silver I am sure it would be appropriate for the job. You have your own jig already and I am wondering whether they would sell you just the solder if your joints still keep breaking.

Originally Posted by Fencepost2

Fossil, for what it is worth, the Australian Woodsmith, No 70 has a couple of pages on "Brazing band saw blades" and it refers to a brazing supply kit sold by Carba-Tec. This kit includes solder - and though it doesn't give the percentage of silver I am sure it would be appropriate for the job. You have your own jig already and I am wondering whether they would sell you just the solder if your joints still keep breaking.

I'm pretty sure that they sell "refill kits" that only contain the solder and flux.

Buzz

Not up to speed on my knowledge on silver solder any more but I'm 99% sure that your prob at this stage is the 2% silver solder, you shoulder be using a 40% or 45% silver solder if my memory serves me right.

If you have trouble sourcing some or want a small amount to try, PM your address to me and I'll send you some from my stock.

Just "did a search" on "brazing bandsaw" and 1 or 2 threads came up.

This one was near the top and seems to answer your question.

Thank you very much all, and thank you for the kind offer DJ.

Big Shed... I found quite a few posts on the subject, but missed the one you have pointed out. Thanks, It explains my problem in detail.

I will get the right silver solder and have another go.

Fossil

mate 1 stick of blue tip solder will do enough blades to be cheap . 2 percent dont bend , try it . breaks , how is it going to flex? costs more in files . enjoy bob

Thanks all very much for the replies.

The solder was the problem, as most have you have indicated.
I went to BOC yesterday and bought a pack of 5 sticks of 45% Silvercoat45T.
The five sticks cost me $49.00, and I use my fluoride plumbing flux.

I just made up nine blades this morning, at an average of a few minutes each.
Nice neat flush joins that only require a gentle rub over with the dremel

Thanks again.

edit....... forgot to mention, brazing up 9 1/2" blades used less than 2" of one stick. Considering the 5 sticks + 100 inches of solder, I am good to go for 450 1/2" blades

Good to hear

Well done

Hi Fossil & others,
I have been making up my own for a few years now. My blades wear out & very rarely break. I am using a Swedish Skip Tooth Blade, 6tpi. x 3/8" . I buy a 100ft of this Blade for $81.70 from McDiven's Saws, Kororoit Creek Road, Williamstown. Vic.
I cut with tin snips 2375mm, square it on the Grinder. Grind it about 1mm. either end, so as they overlap. A friend made me a small jig with 4 bolts & small washers that the blade goes under. I only use it in the vice, with no fear of anything catching fire.
I acquired 16 x 300mm. lengths of Low Heat Silver Solder,at a Swap Meet for $1,
lucky me. They are worth approx. $9 ea. length.
I was given a tip ; put some White Out on either side of the join & quite close. this does not allow the S/Solder to run, I don't no why , it just does.
Cut a small piece off & & put it between the overlap, heat it Red Hot, & when you think it is done, use a pr. of needle nose pliers to squeeze the join together. After removing, I use a large unturned blank in the vice, & holding the blade with my foot, I file both sides so as to clean of the eccess if any.
Be careful not to file to much or you will weaken the blade join. Try it, it does work, & I have no experience in metal working, but if I can do it so can you. I forget to say,
I get 12 Blades @ $7.50 per Blade.
Regards,
issatree.