Furnished content.
(from Lumberjocks.com)
My new flattening jig came about when I bought this ball bearing CNC like set up a guy was selling down the street for 20-25 bucks. I knew immediately this would work well for slab flattening. I used a old 36'' wide standard door and cut it down to 60''. The router holding plate is 3/8'' plywood and screwed to the 4 sliding blocks. I cut a 2 1/2'' hole for the router bit.
I got to use some of my old bandsaw bearings for the sideways movement.They are held in place with a 3/8'' bolt and washer and I made 4 wood knobs and used a wood threader to tighten the bolts.
I screwed the bar guides to the bearing set up and slid them on the 7/8'' bar. This bar has no flex and with the unique bearings in the 4 blocks and the bandsaw bearings it slides around like butter. Up, down, sideways, even a circular motion can be achieved. The best part is only a hand sanding is needed after planing. Maybe because of the smoothness?
I already did 5 slabs and have a few more to go. This jig is for a couple projects coming up.
My old flattening jig which was all wood with wood sliding on wood worked fine but this one makes it look like a antique now and works much smoother.
My total cost for this was 20-25 dolllars. Everything else was scraps or things I had on hand.
Thanks for looking. I'll be glad to answer any questions.