Which Guide Bushing?

[Mike Gottlieb]

I am planning to use a 1/16" router bit for inlay work. Since I will be making a template to follow, which size bushing would you recommend? The bit will have a 1/4" shank. I am thinking
maybe a bushing with a 5/16" inside diameter which would give me 1/16" clearance.

[Bill Dufour]

The inner size does not matter as long as it is more then 1/4". The OD will determine the template offset.

[Richard Coers]

Do you plan on cutting both the inlay and the hole? You'll need two bushings.

[Cameron Wood]

1/4" shank in a 5/16" hole would have 1/32" clearance.

[Warren Lake]

the math is no guarantee as there are tolerances. How well the router base sits centred on the motor, how centered the plastic base is, how centered the template bushing is in the plastic base. It can all introduce tolerances. They will hurt you or work to your advantage. enough times ive set up using one area on the template bushing that is different from the other side using that to advantage or pushing the bushing to one side before tightening. have a number that have been filed to reduce them as well when it would help.

[Dan Cameron]

The inner size does not matter as long as it is more then 1/4". The OD will determine the template offset.

The OD also limits the minimum template curvature that can be followed.

[Mike Gottlieb]

Yes, I do plan to do both. I realize that the ID has to be larger that 1/4". 5/16" will give me a 1/32" clearance - as long as there is not too much deflection, it should work. As for the OD, I want to go as small as possible.