Can This 10” Saw Blade Be Saved?
Online question:
Two teeth came off my “Big Box Store” saw blade. Should I keep using it?
Cheap saw blade with missing teeth
Answer
It depends on how and why the teeth came off.
Typically those teeth are about a C-4 grade which gives you a long life, smooth cuts, a good number of re-sharpenings but sacrifices a little bit of toughness to do this. In a situation such as you describe it is not unusual to see teeth in this grade break when dropped on a concrete floor.
If the teeth popped off because the bond between the carbide and the braze alloy gave way then it is a different matter. You can tell this happened because all you will see in the notch is a layer of braze alloy that is probably gold, yellow, maybe a little orange-ish or similar. It definitely does not look like steel and it definitely does not look like gray carbide.
If the teeth popped out because the braze joint failed then you have to consider the force on the first remaining tooth after the two missing ones. It will be taking about three times the bite it was designed to take and thus will have much greater force on it. In a situation such as yours is not unusual to see teeth “shell” out as much as five or six teeth back.
When these teeth shell out they typically get buried in the wood. Then the following teeth hit the teeth buried in the wood in these teeth break. Typically the tooth still on the saw hits the tooth buried in the wood and they both break. The teeth break in such a manner as to leave small, jagged parts with sharp edges and sharp points.
If it was truly impact damage to the carbide and not a failure of the braze joint then it should be okay to use as long as you take proper could caution against flying debris.
Part of this opinion is based on prejudice on my part. I have been doing tool failure and braze failure analysis for about 30 years. The chances of you actually being hurt by this blade are pretty small but they do exist. Having a piece of shrapnel lodged in your is a painful and very expensive. Most often there is actually nothing that can be done to restore your vision in that eye.
800 346-8274
Tags: circular saws, Quality, safety
Leave a Reply
