On 3/24/2018 4:52 PM, Michael wrote:
....

I can't afford a sander, but I am curious. Sometimes with a thickness planer, you have to shim to board to get rid of a twist. Is that a problem with a dual drum sander, or is that problem eliminated.

Ideally, one has a jointer the size of the planer... then you get
the first surface flat, _then_ plane to thickness. (Even I don't have
that large a jointer to match the 18" PM, though, but normally one can
knock the high points off enough w/ hand scrub plane pretty quickly as
compared to making shims and the backing board.

Altho generally on something that twisted unless it's a really unique
piece of material or very pricey I'll just cut it down to use for
something else that it fits rather than try to correct.

Leon's right though, the two parallel portions of the machine are (and
must be to work properly) immobile with respect to each other as the
material goes through; hence the material is what has to give, mostly.

There's just a tiny bit more "give" in the sander backing rollers and
drive belts, but "tiny" is the operative word.

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