Rail and style tearout/chipout

[David Rose]

I enjoy doing panels in rails and styles. But I continually end up with tearout, most often on the backs of the rails and styles, and a chip maybe 1/4" long on about every 8 or so style ends. I spend a lot of time cleaning these up. To me it is the difference between pretty nice pieces and excellent ones. I've not quite made "excellent" yet. Normally, these patches are not completely hidden.

My wood is often not straight grained along the lengths. The only mill close has a somewhat limited selection. I spend quite a bit of time finding pieces that measure "enough" that is straight enough etc. to be used on my projects. He does s2s only. I have asked for rough, but I don't normally plan far enough ahead to get him to cut it for me. And I would have to take everything if he would. Also, I suspect the dirt in the outer layers of his air dried stuff would really eat planer blades. So the wood with a little angle to the grain is probably a big culprit. But some occurs on pretty straight grain too. All this tearout is with the grain.

This seems to happen with quality *sharp* bits, so I really don't suspect that as being part of the equation. I don't feed very fast.

What do you do to protect against this type tearout/chipout? Do you cut an opposite piece for every cope/stick cut to back them up? I've done that some and still get a little and can have feeding complications. Should I make more than one pass on the cutters? I normally use fairly small cutters, so it isn't needed for other reasons.

I understand the geometry of one (first) pass being a light cut in comparison to the diameter of the bit. Bill Hylton explains that well in one of his router books. I just haven't tried it in this case. That would increase the time considerably. But when compared to "touchup time", maybe not.

I want to produce great pieces instead of "nice". Let the nice part fall to areas where I don't put in enough time, not because of things like this. :eek:

David

[Carl Eyman]

David: I was doing a frame for the door to a GF clock face door - tombstone configuration. I was very fearful of tear-out. So I got some water soluble white glue and glued kraft paper to the surface of the frame ( both rails and stiles). The pieces I had chosen had some wild grain which I'd chosen for its looks. I ran these thru the router for both the cope cut and the other as well as the molding around the outer perimeter. Presto! no tear-out!. I then soaked the kraft paper and peeled off what I could and sanded off the rest when it dried. I'd never heard of the technique before, but it probably has been used. The important thing is - it worked!

[Brett Baldwin]

Just an idea. If backing up the cut and adjusting the feed rate isn't working you might try making the rails and stiles wider than finished width, make your cope and rail cuts, then rip the pieces to finished width. I'm assuming the tearout is on the exits of the cuts here. It is a waste of wood but the decrease in frustration may be worth it.

[Jim Becker]

Yea, you need to use backers as you cut those ends with the profile. One side will likely be a flat backer and the other will need to have the profile milled in.

[Steve Clardy]

I mainly use oak and deal with tearout all the time.
Oak just likes to tear out.
Fresh sharp bits help, but still get some tearout.
I always back up the rail end cut. No tearout.
But the stiles are another journey.
I usually hold the rail out some away from the fence for the first pass. Then make a final pass to clean it up. This helps, but is time consuming.
Oak varies, from one to another. So some chip, some don't. Always a guessing game.

[Mark Pruitt]

This may sound scary, and I would not do it if I were not comfortable with the idea of it: climb-cutting. The miter gauge should give you adequate control to back the piece in very slowly, and I would back it in only enough to cut about a quarter of an inch. Then advance the piece forward out of the bit's path and make the cut as you normally would. This can be dangerous due to kickback potential, but the benefit is that it can eliminate the tearout altogether. It's also time-consuming, but then so is repairing tearout. If you're uncomfortable with this method, try it on scrap. I've done it multiple times and learned that it's doable, but it is absolutely critical that I have firm control.
Mark

[Chris Rosenberger]

I use a backer board when I do copes & cut the coped end before I do the edge profile. When I do the edge profile I attach a piece of 1/4" plywood to the fence & run the edges. My cutters cut 3/8 deep so this first scoring cut is 1/8" deep. Then I remove the plywood spacer & make the final cut. I get 0 tearout on the copes & very little tearout on the edges.

[Ken Garlock]

I agree with Mark.:) After some routing disasters on plywood, I have been using climb cutting almost exclusively on plywood. It does take some muscle to keep the piece against the fence, and sometimes you don't succeed, but as long as you keep the wood tightly against the table top it is no big deal.

I just finished building 8 raised panel doors for a garage cabinet. I just chucked up the bits and ran the boards through one time at full depth without a problem. You just feed the wood at a slower rate. The end cuts on the stiles I backed up with a piece of wood to prevent any tear out as the bit exited the stile.

The same applied to my panel raising bit with back cutter. Run it through one time at full depth with no problem, just feed the board slowly.

[Kirk (KC) Constable]

As someone else suggested, make the end grain cuts on a wider piece, then rip to width. Leave the width a bit proud, then make the groove cut. Run the cut edge over the jointer once, then rout again. Clean cut...

[Rob Blaustein]

This may sound scary, and I would not do it if I were not comfortable with the idea of it: climb-cutting. The miter gauge should give you adequate control to back the piece in very slowly, and I would back it in only enough to cut about a quarter of an inch. Then advance the piece forward out of the bit's path and make the cut as you normally would. This can be dangerous due to kickback potential, but the benefit is that it can eliminate the tearout altogether. It's also time-consuming, but then so is repairing tearout. If you're uncomfortable with this method, try it on scrap. I've done it multiple times and learned that it's doable, but it is absolutely critical that I have firm control.
Mark
Here is an excerpt about tear out from Pat Warner's website (full piece is here (http://www.patwarner.com/tearout.html)). He echoes Mark's point about climb cutting and importance of control. Most sources say to avoid climb cutting on a router table since it can be so dangerous.

"Climb cutting is less efficient than anticlimb cutting and therefore takes more energy. That coupled with tendency of the work or router to self feed can lead to an unexpected loss of control with the hand router or the work being pulled from your hands on the router table - both potential disasters. Very light cuts are permissible but if "light cuts" turns into everyday heavy hogging you should consider using the router table exclusively and only with a power feeder."

[David Rose]

Carl, that is a neat idea! But I'm not talking about wild grain really. It's just seldom nice, straight grain. I will file this idea for the times when I find some really good pieces. I just don't want to get quite this involved (if possible) for everyday rails and styles.

David


David: I was doing a frame for the door to a GF clock face door - tombstone configuration. I was very fearful of tear-out. So I got some water soluble white glue and glued kraft paper to the surface of the frame ( both rails and stiles). The pieces I had chosen had some wild grain which I'd chosen for its looks. I ran these thru the router for both the cope cut and the other as well as the molding around the outer perimeter. Presto! no tear-out!. I then soaked the kraft paper and peeled off what I could and sanded off the rest when it dried. I'd never heard of the technique before, but it probably has been used. The important thing is - it worked!

[David Rose]

Brett and Kirk, the tearout is sometimes on the exit but often all along (for some reason) the BACK of the rails and styles. :confused:

The latest project has lots of center styles. Is that a "muntin"? These are sticking cut on both edges, so no rippy.

David


Just an idea. If backing up the cut and adjusting the feed rate isn't working you might try making the rails and stiles wider than finished width, make your cope and rail cuts, then rip the pieces to finished width. I'm assuming the tearout is on the exits of the cuts here. It is a waste of wood but the decrease in frustration may be worth it.

[David Rose]

Jim, I do use a backer on end cuts. I seldom, if ever get tearout there. Hmmm... I think I am answering my own question... with a LOT of help! :D Thanks guys.

David


Yea, you need to use backers as you cut those ends with the profile. One side will likely be a flat backer and the other will need to have the profile milled in.

[David Rose]

Duh! :mad: Steve and Chris, I made a set of spacers a few months ago in 1/8" hardboard and drilled and tapped the fence and table to hold them! They were made to do exactly that for a large panel raiser. They are hanging somewhat in the way right above the table!!! :o Maybe I need to spend some of my work time looking around my shop and thinking what tools do what. :o

David


I mainly use oak and deal with tearout all the time.
Oak just likes to tear out.
Fresh sharp bits help, but still get some tearout.
I always back up the rail end cut. No tearout.
But the stiles are another journey.
I usually hold the rail out some away from the fence for the first pass. Then make a final pass to clean it up. This helps, but is time consuming.
Oak varies, from one to another. So some chip, some don't. Always a guessing game.

[David Rose]

Mark and Ken, I probably do need to practice some with climb cutting. I am still pretty uneasy about it, though that is the way tenons are cut with the Leigh MFT with a *handheld* router. I've done some 'accidental' climb cuts on the table that were rather shocking as to events that followed. :eek: I was taking precautions, so no damage to *me* occured, but... :( I just need to learn to do it right.

David


This may sound scary, and I would not do it if I were not comfortable with the idea of it: climb-cutting. The miter gauge should give you adequate control to back the piece in very slowly, and I would back it in only enough to cut about a quarter of an inch. Then advance the piece forward out of the bit's path and make the cut as you normally would. This can be dangerous due to kickback potential, but the benefit is that it can eliminate the tearout altogether. It's also time-consuming, but then so is repairing tearout. If you're uncomfortable with this method, try it on scrap. I've done it multiple times and learned that it's doable, but it is absolutely critical that I have firm control.
Mark

[David Rose]

Rob, I'll read that. Thanks for the link.

David


Here is an excerpt about tear out from Pat Warner's website (full piece is here (http://www.patwarner.com/tearout.html)). He echoes Mark's point about climb cutting and importance of control. Most sources say to avoid climb cutting on a router table since it can be so dangerous.

"Climb cutting is less efficient than anticlimb cutting and therefore takes more energy. That coupled with tendency of the work or router to self feed can lead to an unexpected loss of control with the hand router or the work being pulled from your hands on the router table - both potential disasters. Very light cuts are permissible but if "light cuts" turns into everyday heavy hogging you should consider using the router table exclusively and only with a power feeder."