replacing broken tooth/"shoulder" on forrest blade?

[Zach England]

I went to put my forrest woodworker II on today, and much to my surprise one of the teeth and what I believe is called the shoulder is missing. That is, not just the carbide tip, but the steel behind it. It's completely gone. On their website forrest gives me the impression that they will fix this for $19 and I was going to send another blade to them to have it sharpened, but is it worth it? Forrest says it comes with no warranty and is at customer's risk. Should I just buy a new blade?
Thanks.

http://i121.photobucket.com/albums/o237/zachslc/IMG_0329.jpg

[Ken Fitzgerald]

Zach,

I moved your other thread to the Moderator's Forum. We seldom delete threads so we alway have them should any legal reason pop up.

[george wilson]

I don't understand. Was the blade sold by Forrest as a "second" or something,so it isn't warranted?

I cannot see how they could "repair" this blade.

[Larry Frank]

I really wonder what happened. I bet someone at Forrest could and would like to look at the fracture surface and figure out what might have caused the fracture.

[Zach England]

The blade has been hanging on the wall for at least the past month. I know I've never dropped it, because I'd inspect it if I had. I've hardly used it since I discovered the CMT combo blade I have been using lately. The only thing I can think is that I bumped something into it while hanging on the wall, but I can't imagine what would cause that to happen. It was purchased new--I believe from Lee Valley. I didn't know they had a warranty.

[Paul Atkins]

Must have been the tooth fairy.

[Wayne Cannon]

Have you talked to Forrest? They've always been very responsive and open to sharing their knowledge.

[scott spencer]

It's worth fixing, but since the whole shoulder is gone anyway, I wouldn't worry much about actually using it as it...nothing's going to fly off. I wonder if something was wrong with it before you used it?

[Dwayne Watt]

Talk to the folks at Forrest about replacement of the blade. If nothing else, they should be interested in the serial number on the blade. Tough to tell much from the photo, but that failure surface has characteristics of a brittle fracture. It is also right at the edge of what appears to be a heat affected zone on the blade. This suggests a processing problem may have occurred. As such, I would not use this blade after a single tooth repair simply because there is possibility of other teeth having similar problems given the assumption that this is related to a material processing problem. I do recommend you have a civil conversation with the folks at Forrest. Odds are good they will work with you on this.

[Keith Christopher]

I had this happen to a systematic blade I bought once when ripping some which oak. The blade is ruined. You'll need a new one. I would contact Forrest, what's the worst they can say....no ?

[Tom Walz]

I would not use it. There is a good possibility that you may lose additional shoulders.

In most professional situations that would be considered a defective blade.

Saw steel is cut in a soft condition. Then it is heat treated to make it hard. After that it is tempered to bring it down to the proper hardness measured as a Rockwell value. This is often somewhere in the mid-40’s on the Rockwell A scale.

However it takes heat to braze tips on and the heat can reharden the steel. Hard steel is brittle and can snap. What you have there looks like classic case of chill line fracture. The chill line is the line where the hard steel meets the soft steel.

I was called in to solve the SystiMatic problem. They had automatic machines that followed a program. However you could tell by looking at the color of the steel that the machines were brazing at much to high a temperature. It turns out the machine had never been calibrated. They were just installed and used.

We sell tempering units to top end saw shops that retemper the shoulder after brazing and many automatic brazers have this as an included feature.

It used to be common practice to build up shoulders that had been ripped off by welding and to drill the end of a crack so it doesn’t run any farther. The best shops will not do this because it simply cannot be done well enough to bring the blade back to its original condition. It is also a very dangerous practice. Finally OSHA prohibits it. OSHA regulations Federal Register part 11; Department of labor (OSHA); Title 29, chapter XVII; Section 1910.213; Paragraph (S);

[scott spencer]

Zach - It must have been early b/c I completely overlooked the possibility of other teeth & shoulders being defective. It's better to error on the safe side and not use the blade until it's inspected. Apologies for the potentially dangerous oversight!