Is my bench top flat enough?

[Dick Holt]

I just bought (off Craig's List) an oak butcher block table for $30. It is 60" x 36" x 1.75" and in great shape. I will be using the top to replace the existing top on my work bench. If I put a straight edge across the width, there is a gap of .020 in the center. Is this flat enough or will it cause problems?

Dick

[Andrew Hughes]

Sounds like a good find,If the top doent have a twist its probably not a big deal.Check for twist with winding sticks or two levels.

[David Ragan]

I have to ask, given that the eye would never pick that up by itself:

What is your interval of measurements going down the bench, i mean, does it undulate?

How do we know that this is the maximum amount of anomaly? How about humidity and temperature swings, as wood is infamous for?

[glenn bradley]

I'd be happy with that but, would be more concerned in checking over the span of the bench. That is; a fat 64th in one spot wouldn't bother me but, if the far end were 1/4" lower than the spot I'm checking I would fix it.

I imagine the top if fine but, it really depends on how you will use it. Will it be a Schwartz-like bench that has the primary function of making boards? Will it be your assembly area as well? For most furniture building 1/64" irregularity is not going to bother me although I'd rather not have it.

As to wood movement; you bet it does ;-) Depending on your environment, the top may flex much more than that in a day. I have a reference surface bench made of MDF for squaring parts and assembly. For roughing out boards, my needs are less strict ;-)

[Allan Speers]

I would let the top acclimate to your shop for a while, then recheck.

After that: What Glenn wrote above, exactly.

For my work, it would be just fine. More important is to check it for twist. make a pair of winding sticks, and get to it.

[Nick Stokes]

You're top is flatter than any workbench in my shop, including the top of the workbench I just finished building. Heck, it might even be more flat than my table saw top, I wouldn't know, I don't have a way to measure a top that large to those tolerances.

[Dick Holt]

Thanks for the suggestions. I didn't think to let it acclimate for a few days.I will let it sit for a few days and recheck and also check for twist. My workshop is in the basement with a duhumidifier and it is a constant 55% hunidity, lower in winter.

Dick

[Brian Tymchak]

At 1.75" thick it might distort a bit when fastened to the bench base, also depending on how you attach it. I'll recommend that you install the top first, then check for distortion and adjust accordingly.

[Brian Holcombe]

IMO, I think it's important to check for twist....which is what will drive you crazy in use. If you don't have a set of winding sticks, then make a set and use them to site the top for twist.