slotted screw holes to allow wood movement

[sliv33]

Can someone tell me if the slot to allow wood movement should be equal to, or larger than the diameter of the screw, for example when attaching a top to an underlying moulded frame?  Thanks.
Arnold

[Martin S.]

I can only tell you what I do...and that is make it one size (1/64") larger than then the screw.  You want the top to move freely. 

I saw a neat trick (mind not very period trick), but if you have a Festool Domino, you go all the way through with the smallest size and then plunge in just a tad with a larger size make resessed spot for a flat head screw to sit.

martin

[handi]

Martin,

Again, not terribly period, but most major router brands now sell bits that cut both the through slot and a counterbore or countersink in one tool.

Ralph

[sliv33]

Thanks for your input.  Sorry for the delay in getting back to you , but have been out of commission for the past three months.  Arnold