Track saw blade offset

[Spectric]

After @Doug71 provided some good info regarding the offset on tracksaws that I had not fully understood I looked into this to get a better understanding and now can see that it is the combination of both blade thickness and kerf that determine the offset, or the amount of rubber strip initially cut. Maybe just me but I had thought that it was just the kerf and so you needed to use the same kerf blades to ensure rubber is either not cut again or you have a gap.

Simple diagram shows this. Anything overlooked or wrong?

 

[porker]

Looks right to me. For clarification you are calculating the offset from the 'boss' that the blade sits against - (Kerf Thickness - Plate Thickness)/2. If the offset number increases more rubber will be cut. If it decreases the blade will move further away from the rubber strip.

 

[Spectric]

Yes and now I can see that using blades with differing kerf and thickness is ok so long as they all give the same offset. When you look at Makita blades it seems that the offset is less for the blades designed for their cordless saw which are thinner blades to give the batteries an easier life.

 

[Phil Pascoe]

I have only the cheapy (just gone up £26) Evolution, but they advise to cut the strip with the blade you're going to use, and use a different strip for a blade change.
I use a 80T blade, 1.7mm kerf - I have been told this too fine but it leaves a perfect edge. I need to cut only sheet stuff, and should the need arise I have other blades anyway.

 

[Spectric]

thats a lot of teeth on such a small blade, but with a bandsaw they say you should always have between three and ten teeth in the workpiece which I don't think works on circular saws as they are not linear.