This guy feeds the support strip end into the planer first. At 1:40 he calls it a "toe kick" and says that it prevents the board from "sliding right off" as he is pushing the sled through.
This guy feeds the end without the support strip in first. At 5:50 he explains that the blades spin towards the infeed side of the planer and the support strip prevents the board from being pushed back out towards the user.
2 - Probably a silly question, but I'll bet it starts a discussion...
If the sled works for flattening a twisted board, wouldn't it also work for flattening a bowed board? Assume a board that is flat for most of its length, but with a bow upwards towards one end. If you shim that entire "raised" end, not just a corner like is done with a twisted board, That face will eventually be flattened and when board is turned over the hump will be gone, just like the rocking of a twisted board is eliminated, correct?
3 - This question isn't really planer sled specific, but it could relate to the shims, so I'll toss it out anyway.
Is there a certain brand or type of hot melt glue that pops off wood easily? I don't use hot glue on wood very often, but it's mentioned in both, and used in one, of those planer sleds videos.
Whenever I've use hot glue on wood, the 2 pieces separate pretty easily but the glue has to be mechanically (serious scraping) or chemically (alcohol) removed. I know that 2 sided tape is an option, but in cases like the first video above, where the shims are slid into the gap, the hot glue method seems the easiest to install but might be hardest to un-install.
As always, thanks for any advice and tips.