What size should a 10" blade be?

[Tom Walz]

There is a discussion under way on this here. Some 10” saws are made undersize so they can also be sold as metric saws.

There is also a discussion in the professional saw sharpeners web site about tolerances for manufacturing blades.

This can be a real problem for sharpeners because it is hard to restore a saw to like new condition if you don’t know what that condition was. In many cases the sharpener uses tighter tolerances and makes the saw better than new.

Quite often a sharpener has a heavily worn saw and can’t determine and restore the original angles.

So my question is what size should a 10” saw blade be and how tight should the tolerance be. We track total runout and find big box blades to have 0.004” at the best with 0.006” common and some much worse. 0.003” total runout seems to be about the best achievable in 10” blades.

How much should thickness vary from blade to blade and how much variation should there be in the width of the tips and the length of the tips.

Since there isn’t any standard now I guess whatever you guys come up with will be a new industry standard.

Thanks,

[John Coloccia]

I guess I'm curious why in this year of our Lord, 2010, any manufacturer can't trivially manufacture any darn thing they well please and make it exactly 10" as best as I can measure with a normal ruler? Maybe a variation of 1/16" or 1/8" to take into account that they may be grinding different blade profiles using the same blank, but even so I just don't get why there's so much variability.

Maybe someone in the biz can clear this up for us. There must be a reason other than carelessness or cost because I just don't see it costing that much or being that hard to come pretty darn close without using any exotic technique or equipment. The same technique that makes it 9 7/8" can just as easily make it 10".

[scott spencer]

...The same technique that makes it 9 7/8" can just as easily make it 10".

They probably start at 10" before sharpening, then whittle them down to 9-7/8"....kind of like lumber! :D

Minor deviations in diameter don't bother me as long as they're consistent for stacked sets and within the same model #. It would be nice to see some standardization of kerf widths for the sake of splitter matching. There's no real set standard, but full kerfs tend to be ~ 0.125, and can vary alot...some down to 0.110 others up to 0.155". Thin kerfs tend to hover ~ 3/32", but can range from 0.90" to 0.107"...add the confusion of "ultra" thin kerfs and things get complicated. Heck, not all the manufacturers even state the actual kerf width, which seems like a safety hazard to me.

[Dan Friedrichs]

Tom, I always thought that was a bowling ball you were holding in your avatar picture - it now occurs to me that it's a saw blade :)

[Van Huskey]

Sawstops and riving knives are adding to issues that didn't seem to surface in the past. Saw manufacturers did what worked for THEM and each one is different apparently.

[Tom Walz]

Dan,

Never noticed before but you're right.

The IT guys say I need a better quality picture. Guess they are right.

That was the first ceramic tipped saw blade. We used TiCN (Titanium Carbonitride) instead of Tungsten Carbide with a CoCr (Cobalt Chrome) matrix instead of straight Cobalt.

It cost about $10,000 to build. The tips were about $10 each. It has been a long time and those aren’t exact figures but the range is right. The big expense is in the grinding. When you use a high wear material it is also very hard to grind.

Anyway it worked and we proved the concept then moved on to better material blends such as Tungsten Carbide / Titanium Carbide / Titanium Nitride with Vanadium and Niobium.

Tom