I've tried end grain through my planer some worked some met the back wall of the shop at 256.9 miles an hour. Now I use a router sled and flat cutter. Just like you would use to flatten a benchtop. Light cuts and slow motion do the trick.

That's a good suggestion and one I was considering.

I didn't see anyone mention a router table with a backer board fed through with it for each row.

Glue up should be pretty much dead flat if clamps are arranged top and bottom alternating.

So I'll throw that in.

Edited July 18, 201511 yr by DRAGON1

 router sled

That's probably the best way to go about it.

If the glue up is funny shaped you can shim it till it sets perfectly and the router won't impart any warp or twist.

 

Thanks for the tip

Yep.... A router sled works great for this...