End Grain Tear-Out on a Shaper
How can tear-out be minimized when running end grain across the cutter head? April 21, 2011
Question
We are in the process of making box newel staircase posts. They have a skirt at the bottom 5" x 5" x 8 inch high with mitered corners. We are passing that piece vertically on a 3/4" shaper with a 1/8" and 3/8" quarter round and 1/4" bead, three wing cutter and we are getting a lot of chips or tearout. This pass makes a cut cross grain with the wood grain vertical. Now I have tried with up to four pass to get to the full depth and still have a lot of tear out. They are mostly made out of maple or red oak. The red oak is more of the problem. I’m currently passing them by hand with a slow feed rate as with the feeder they seem to have even more chip missing. Does anyone have any ideas as to what I can do or what I’m doing wrong?
Forum Responses
(Solid Wood Machining Forum)
From contributor M:
I am a little confused as what detail you are using, but why not apply the detail before mitering? We ship a lot of newels with the base wrap loose and an applied cap mould to be installed after mounting the newel.
From contributor P:
You could make the pieces a bit over size (equal to the worst chip out) or try a backer piece going through the shaper. Carbide cutters are never very sharp and just can't come to the end of a cross grain cut without sending some extra wood flying. If you have many of these to do try a backer piece, just have a few of them and send one right behind each price. Even the backer has already been cut on the shaper a backer piece will help.
From contributor L:
Sounds to me like you're trying to run this detail on the end grain (cross grain) right? If so, there's no way it's going to work. I build lots of newel posts like this. I run the lower skirt as you call it with grain running vertically like the rest of the post. I miter the corners on the table saw. I then apply molding mitered at the corners to get the detail look you're after. Since there will be wood movement issues, I make mitered squares, glued and pinned at the miters, a bit oversize so the post can expand and contract. I do not glue, but only pin these squares (pre-assembled like picture frames) to the skirt pinned only in the center of each piece.
From contributor R:
Sometimes I make drawers using a lock miter cutter. To hold the drawer pieces vertical, I use a tenoning jig. I don't have tearout issues. I slow down my feed rate for the last inch but that is all.
From contributor I:
Have you tried climb cutting? Feeding the stock backwards with the cutter still running in the proper direction? You must use a powerfeed for this and be prepared for a lot of dust shooting out from the lead of the board. It does work pretty well though.
From contributor R:
I recently tried climb cutting with a feeder and it eliminated all of my tearout issues.
