snip and a Ryobi planer

if its sniping on the tail end of the cut the front edge of the board is probably dropping a little.

You need to look at the typical length of material you are going to be planing .

I use about 2/3 that length for a support table although full length is better.

so for 4' material a 4' infeed and 21/2' outfeed is fine .

I made mine out of a single sheet of plywood covered with hardboard. It's the width of the planner and about 4.5' long. (half sticks out on each side of the planer). I have a small board attached to the bottom to keep it from feeding through the planer with the boards. If I were to make another one, I would raise the ends by inserting a sheet or two of veneer between the ply and the hardboard to raise the ends by

Anything between 12-20" will help. Also, try to slightly lift the end of the board when it is just about finished planing. (On the outfeed, of course).That way, when the back roller is no longer supporting the board, the board won't "tip".. which causes snipe.