spaco wrote:
....

I don't think I will be doing this on a regular basis, but the sled idea
sounds like the way to go anyway. I have a lot of rough sawn hardwood
around here, so the sled might get more use once I have it.
....

[Trimming and not top-posting would surely be nice for thread continuity
and ease of conversation...]

Indeed sleds are wonderful devices but...

For the initial "knock it down to flat" work, simply tacking wedges or a
strategically placed cutoff of the proper thickness to stop the rocking
is another "trick" I use quite a lot.

All you really need is enough to get it through on a single plane a
couple of times. If there is twist and it's long, bringing it down to
several shorter sections based on the project size first is generally
worthwhile to both make the process simpler and to also save as much
material as feasible.

Also, severely cupped or bowed pieces may be far more effectively
utilized by ripping and regluing than trying to flatten the entire board
-- the wider it is, the more likely this is to be beneficial.

What you have to avoid, of course, is the feed roller pressure
flattening the piece as it goes through and then it returning to its
original shape after passing thru albeit w/ parallel (but not straight)
surfaces. This is obviously less of an issue as one gets to thicker and
thicker original stock; 8/4 hardwoods one may manage to use minimal
pressure necessary to feed and only deal w/ the rocking issue and do
quite nicely whereas 4/4 of the same material will need full support.

Experience is the best teacher--nothing ventured, nothing gained...

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