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Cliff Polubinsky
09-11-2021, 9:12 PM
I often see the observation about track saws that when you use a blade with a different kerf that it changes the width of the splinter guard so that it no longer indicates the actual cut. But whether you mount a narrow or wide blade, the edge of the blade next to the saw body is in the same position, therefore the splinter guard is not changed.

What am I missing?

Cliff

Dave Zellers
09-11-2021, 9:25 PM
If the offset of the carbide tooth is more then you have the situation you describe. But it would be teensy weensy.

Paul F Franklin
09-11-2021, 9:47 PM
Two blades can have the same saw plate thickness yet have different kerfs, so the cut line would be different for the two blades. But as Dave Z. points out, the difference is small.

Lee Schierer
09-11-2021, 9:59 PM
On my 10" blades, the thin kerf blade has a plate thickness of 0.074 and a tooth width of 0.097 a difference of 0.023 or 0.0125 over hang from the plate on each side. My full kerf blade has a plate thickness of 0.080 and a carbide thickness of 0.127 a difference of 0.047 0r 0.0235 over hang per side of the plate. Therefore there would be 0.011 difference in distance from the saw body to the edge of the teeth when switching between a thin kerf blade and a full kerf blade.

I can't comment whether this difference has any real effect on the offset of the splinter guard. The difference could be even less on the typical blades used on skill saws.

David Buchhauser
09-12-2021, 1:15 AM
I often see the observation about track saws that when you use a blade with a different kerf that it changes the width of the splinter guard so that it no longer indicates the actual cut. But whether you mount a narrow or wide blade, the edge of the blade next to the saw body is in the same position, therefore the splinter guard is not changed.

What am I missing?

Cliff

I am still using the same kerf width blade that came with my Makita track saw. When the track was new, the first cut trimmed the rubber splinter guard so that for all subsequent cuts the edge of the blade rides right along the edge of the splinter guard. When I mark my plywood with a sharp pencil mark at each end (or side) of the sheet, I then align the edge of the splinter guard exactly to the sharp pencil marks. This gives me a pretty "perfect" cut dimensionally.

If I were to replace the current blade with one with a thinner kerf, but still use the edges of the splinter guard to align my track, my cut would be off by 1/2 of the difference between the kerf width or the two different blades. If I were to install a blade with a wider kerf width than my original blade, then the first cut with this new blade would trim the splinter guard so that for all subsequent cuts the edge of this new blade rides along the edge of the splinter guard.

If I now switch back to one of the thinner kerf blades - and still use the edge of the splinter guard to align my track to my marks, then my cut would again be off by 1/2 of the difference in kerf width between the two different blades.

David

Max Neu
09-12-2021, 7:22 AM
Have you thought about shimming the thicker blade over?

Dave Sabo
09-12-2021, 7:59 AM
Don’t forget the splinter guard is also there to ……………..um , help prevent splinters on the top of the workpiece.

Using a blade that’s not matched to the splinter guard will cause chipout on the panel. Some may not care because they’re just using the tracksaw to rough dimension sheets to take to another tool. If you do care - buy blades with the same kerf or replace the splinter guard. Both are easy to do.

Ever used a tablesaw and wondered why the rip fence cursor is movable ? ? ? Yup, to account for different kerf widths

Cliff Polubinsky
09-12-2021, 10:29 AM
Thanks, all. Evident senior moment. Didn't think about the tooth width changing.

Cliff

Osvaldo Cristo
09-12-2021, 11:02 AM
The saw blades are mounted on the same harbor at the same point so the internal face of blade when mounted in the saw harbor will be exactly at the some point related to the saw body and, of course, any guide it is attached to. If you use the inside part of the saw as reference, it will be independent of the saw thickness.

On the other hand, today most saw blades have hard metal teeth that go outside the limits of the blade thickness. In those cases the cut will be slightly more inside: the half of the difference between actual teeth and blade thickness.