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I have a rip fence on my circular saw similar to the one here. What are the holes for? Can I add a longer piece of metal / wood to extend the fence? Wouldn't that then make the measurements on the fence inaccurate?
The holes are so you can attach a straight longer piece of wood to it.
It will affect the distance, but you can gain accuracy. Measure and mark is always safer than using the measurements on the gauge.
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