Climb Cutting End Copes
Advice on a tricky machining technique for stile-and-rail door parts. August 15, 2006
Question
I been pondering running long pieces of stile and rail in advance for my doors, then climb cutting my rails. I have heard of a few people doing this, but how in the world will I do the end cut on the rails? Will I put them in the sled, then run the sled with the power feeder?
Forum Responses
(Cabinetmaking Forum)
From contributor A:
You will find that climb cutting end grain causes deep pull out of the wood fibers. Climb cutting on long grain with a power feed and taking light cuts will work but be sure you have your fences set so the cut can't get too deep. Keep plenty of pressure on the feed wheels, and wax the table well. If the stock starts to jerk as it feeds, it's very near losing control! Shut it off or run like hell. Climb cutting is best used when you have very difficult wood (curly maple). But climb cutting doesn't leave as clean a surface as conventional cutting so you either sand more or make a second pass conventional cutting a very thin amount. Keep your feed rate fast enough that you don't cause heating since you don't have enough chip to carry much heat away from the blades. Keep the path clear in the direction of throw, sooner or latter it will happen.
From contributor B:
Do you want to cut your cope after you have your edge profile? If so, when you have your cope cutters in, run a length of material along the edge. Then take this piece and use it as a backer against your miter fence. The pieces should fit and you will prevent tearout.
From contributor C:
Here's one method - instead of a bunch of skinny parts make the rails wide enough to get multiple pieces (example- if your finish width is 2-1/2", make a 6" rail, then split it for two), cut them to length and run the cope normal with the sled first. Then cut them to width and get rid of any tear-out, etc. It's so much easier to get good parts when you leave yourself a chance to eliminate defects. It usually helps to make a few extra parts in case anything bows when you start ripping.
From the original questioner:
Yes, I want to climb cut the cope cut. The reason is to be able to run 10ft long pieces of stick and stock them up. I have heard of this being done. I guess I could just prerun the stiles - that would speed things up a little, but I would still like to know how some people climb cut the cope cut. I do appreciate all of the suggestions. I presently cope first then remove tearout on the stick cut. I don’t want to add another step to the process. I am hoping someone that is climbing the cope cut will read this. Anyone have a good source on rub bearings?
From contributor D:
Climbing your copes with finished edge stock won't eliminate blowout on the edges. At 3k to 6k, the knives are going much faster than the sled/table/feed is running. This is done with two counter rotating spindles, identical tooling, with each cutting just over half the width of the part. Look at Unique Machinery, Jensen, Stegherr, and all the big double end machines.
The low tech way, with symmetrical tooling top and bottom, is to cope halfway thru the part, flip it over and cope the rest of the way, all with conventional feed direction.
From contributor E:
I have cut the cope on a climb with mixed results. As said, it can pull the grain or cause some tearout on the entrance side and not the exit. I use a sled clamped to a sliding table for absolute rigidity. If there is any play in your sled travel, things get ugly. The siding table keeps things from taking off. I also find that the inserted style cope cutters are more forgiving than the brazed type when doing the cope climb cut.
If you want to keep long sticking lengths and cut and cope after, you can use a backup block that has the cope machined in it. This will be part of your sled. The only issue is that it has to be tight fitting and you have to tap the piece in and out with a mallet. Not always a good idea with the machine running.
From the original questioner:
I understand two cutters rotating towards each other. I have used the backer block - maybe just run some long pieces and cut them for stiles, then do my rails cope cut first.
