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How Thin Can Saw Blades Get
To: Sales@carbideprocessors.com Subject: How thin can you go with saw kerf?
Good afternoon, I was wondering if you can tell me if there is a limit on how thin of a plate gang saw you can run carbide on. I’ve been told that if you run to thin of a plate saw that the carbide tips will break out because there is not enough bonding surface. I’m assuming there is no minimum plate thickness and the reason for the tips breaking out was because of over heating while tipping. Could you let me know if there is a thickness limit? Thanks
Great question.
State of the art seems to be about .060” kerf on a 12” saw blade with a blade change every sixteen hours.
The thinnest we have gone with carbide is 0.025”. We know a filer in a mill who runs .053” kerf. He came up to me after a speech and told me this but told me it was proprietary. I called Steve Hartshorn at Peerless Saw Co. He says that they do regularly sell edger saw plate that is .060” thick but those sales are maybe 2% of all edger plate sales. Steve Bergerson of Western Saw sells .047” plate for use in a 12” gang edger. Super Thin saws advertises saw blades thinner than a dime of course these as small diameter saws for ripping window blind slats and similar.
The brazing works very well if done properly and there is no tip loss or ripped shoulders. This is particularly true if the blades are annealed after brazing.
The big problem seems to be saw plate distortion. Stellite® and our Talonite® both have a higher lubricity than ordinary carbide. However our cermet II is much slicker than ordinary carbide and slides through the cut much easier.
If plate condition is the reason for saw changes then our cermet can take a mill from a change every four hours to every eight or sixteen hours.
If the tip comes off it is because one of the surfaces was not properly prepared or the wrong braze alloy was used. A good braze joint creates a chemical bond and an intermetallic compound. A bad braze creates three distinct layers. Think of plywood with and without glue.
A good braze creates a bond stronger than the materials being joined so tips do not come off.
Braze alloys differ greatly. If you use the wrong braze alloy you can rip the alloy in half. The right alloy will, again, give you a joint stronger than either material.
If everything is done properly then the saw tip has been braze treated so that it wets and bonds well. In addition the plate will have been gummed past the heat affected zone from the laser cutting and it will have been properly cleaned. Finally the right braze alloy and flux can make a huge difference.
Carbide Tip
This is a piece of carbide .5” by .025” butt brazed to a matching piece of steel. I put it in a vise and tightened it a bit to get a bend and test for strength. You can see by the bend how much pressure is on it. I think it would have taken more bending but I don’t know how much more. This was just a quick demo shop.
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