Flattening a twisted board

[Greg Labacz]

I have some old poplar boards that are roughly 12" x 7' and was going to use them to make band saw boxes. Should I cut them to a rough size for the boxes and plane one side with a hand plane and then run through my planer or should I try and do it to the whole length. I have a planer, band saw and router table and table saw.
any assistance would be appreciated.

[Howard Acheson]

You will have less waste if you cut them to rough size first. Then flatten one side and use a planer to flatten and make the second side parallel.

[Andrew Nemeth]

I might cut it down some but leave several blanks together so that you are not planing short pieces. 7' is more work but 12" has it's own set of problems.

[Will Overton]

Howie, is correct ... big surprise.

In cutting to size first you may find some pieces with little or no twist. If you are using a thickness planer, make sure the pieces aren't cut too short.

[Loren Hedahl]

Rather than a hand plane, I initially use an old Makita power plane for hogging off high spots in stock. Once it is close, after a pass or two through a jointer and it's ready for the planer.

For boards too wide for my 6 inch jointer, I just go from the power plane directly to my lunch box planer.

[Peter Aeschliman]

If the boards are truly twisted (not cupped or bowed, but twisted), I can't picture how running them through the planer could possible solve the problem. One side needs to be flat first, so it can slide along the planer table and provide a reference for the opposite side...

If you send a twisted board through your planer, it will teeter and/or roll as it passes through. Sure, it will make the opposite side FLATTER, but it won't make it FLAT.

If the twist is really subtle, then I guess it might work.

Definitely cut the planks shorter first... but I think you'll need to figure out a way to fully support the side of the stock that will rest on the planer table as it passes through.

One method that will work is making a planer sled. That way you can support the two corners of the boards that are higher than the other two (which would be opposite corners from one another diagonally).

Loren's approach might work two- use a hand planer to sort of flatten one side, take it to the jointer and completely flatten that side, and then you have a flat reference for the planer.

[Steve Southwood]

Another vote for planer sled.