Bevel cuts and translation of blade

[Chadi]

I just picked up at BT3100 and enjoying it. This is my first time on a table saw and was suprised when my first bevel cut came in about 5/16 to long. For some reason I thought the blade pivots so I wouldn't have to add any length to my measurement. Needless to say I realized the blade moves away from the fence about 5/16 at 45 degrees. That was determined just by some hand measurements. So from now one when I make a bevel at 45 degrees I'm going to have to subtract about 5/16. Is there a better more accurate way to make bevel cuts and determine the movement of the blade at different angles?

Thanks,

Chadi

[LCHIEN]

The pivot point for the blade bevel is below the table top so yes it will always translate on virtually every table saw out there.

There's been talk for years about whether to even use the scale on the rail to set the rip fence. Some say they never trust it and set the distance with a steel rule, I find it highly trustworthy provided of course its set up right for zero width at 0° bevel.

So the translation could be resolved to a geometry problem and you could figure the translation as the sine of the angle times some offset but I know of no one who's done that. that would amount to not only trusting geometry (and a lot of people here don't even undertand trig any farther than you can throw a tangent) but also trusting the scale again.

Furthermore are we interested in the rip width at the top of the workpiece or at the bottom?

I think the standard way of handling the issue is to literally measure the distance with a thin, steel rule either on the table top (give you the width at the bottom) or laying on top of a piece of stock the thickness of the workpiece (gives you the distance at the top), making a test cut and verifying the distance you get is the one you want. That's how I do it.

Good luck! And welcome to the forum.

[Chadi]

Thanks for the input Lchien

Chadi

[RodKirby]

What Loring said - the only accurate way!

On ANY table saw.

[monte]

Welcome to the group. Use a steel rule and measure the cuts. That is more accurate anyway.