Table Base out of square

[Luis Reyes]

Hi All,

A pretty basic question here but I can't seem to find an answer on google. I'm building a mitre station out of 2x4 with a plywood top and plywood shelf. I've realized that the frame I made for the top is out of square by 1/2 in and same for the shelf base is out of square by 1/2 by measuring diagonally. I realize this means one side of the frame is longer than the other but no matter what I try I can't get it to be perfectly square. What's the trick? My boards all measure the same and seem to be set at 90 degrees but I'm assuming my 2x4's have a little twist or bend.

[John Kananis]

Most important thing is, start with square stock. At this point, try clamping diagonally with a pipe clamp.

[lou Brava]

Maybe this is to simple, but just use the plywood top to square up the base. Same goes for the low shelf your plywood will square everything up.

[Luis Reyes]

Maybe this is to simple, but just use the plywood top to square up the base. Same goes for the low shelf your plywood will square everything up.

I never thought about that! It's a great idea!

[glenn bradley]

I think Lou has the answer for you. There are a lot of 2x4 type structures that rely on the sheathing to provide racking strength. Pull your frame as close to square as you can get it and attach your plywood. You will want to also press the frame to a flat surface to make sure you don't correct one plane and throw the other out of square. This process has been a good lesson in assuring your parts are square and true before assembly. Square parts yield square assemblies :).

[Steve Jenkins]

Square parts are certainly important but even if everything is straight and square you can pull it way out by how the clamps are positioned. When gluing up don’t assume it’s square but check it at every step.

[Richard Coers]

I would have built the entire bench out of plywood. No idea why you want to bring wet framing lumber into the equation. You sure don't need extra structure to just hold up a miter saw

[Mark Wedel]

Whenever I'm building something out of 2x4s and want accuracy, I mill them down. 2x4s from the big box stores are anything but consistent - width and thickness can vary, in addition to them having twist or cupping. So I put them through the jointer, planer, and tablesaw and get everything truly consistent in width and thickness. It is more work, but gets better results. Whenever I skip that step, think "oh, it's not a big deal in this case", after finishing things up and running into these issues, wish I had did the extra milling step.

[Rich Engelhardt]

Whenever I want anything close to accurate using a 2xX, I start with cutting down a 2x6.

Usually the 2x6s are a whole lot better and not as expensive as the decent 2x4s. (if you can get two pieces out of a 2x6 - otherwise, they are more expensive)