Profiled edge tear-out

[denis tuomey]

In the process of making 3 raised panel kitchen cabinet doors and 2 drawer fronts out of Red Oak to match existing cabinets, finally found a combo of 2 bits , a 1/4" and a 3/8" Core box bit to put the outside edge profile to match the existing cabinets. Got them glued up, cut and squared to size, when I ran the panel vertically thru the shaper with the 1/4" bit it did fine till it went across the grain on the stile-got extremely bad tear out on the grains, big gouges. The cutter is cutting a 1/2" up and less then 1/8" into the wood.When puttyied and stained, the putty, (tried both Birch and Red Oak) stains up much darker=very visible. Tried 7000 and 9000 speeds and same results. Now I have to re-make 2 doors and 1 drawer front. Anyone have any ideas on how to make these cuts without the tear out???:confused:

[Matt Tawes]

I like to make panels running the panels with horizontal bits and the material flat on the table (vertical bits suck most the time, just my opinion) but in your case improvising you likely dont have that choice. Run your end grain first on each end then your long grain which will smooth any tearout. And incidentally for rail cope cuts just use backer blocks to eliminate tear out there as well. Oak is tough anyway with its open grain its prone to splintering very easy with tearout.

After re-reading your post I realized it appears to be the endgrain on the outer edge rails/stiles of the doors your cutting and not the actual raised panels.
If the tearout is on the very edge try to use some sort of backer block to keep the bit from blowing out that edge. Also as I stated above try running the end grain first then the door edges which if any tearout the long grain cut of the profile should smooth out whatever tearout resulted.

Sorry, it was tough to visualize what you implied with out a picture when I read it (I read it too fast I guess) when you were talking about running the "panel" vertically but then said you had tearout on the "stile".

[glenn bradley]

"I like to make panels running the panels with horizontal bits and the material flat on the table"

Denis states he is using a shaper but the recommendation for end grain first with a backer and then long grain is a good one. I try to use this method always and generally pay for it when I don't. ;-) If you are getting tear out on the end grain in the middle of the board end (that is, not only at the exit point), that is generally a poor cutting edge or poor material control past the cutter. Sharp cutters, a tall fence for support and stacked featherboards are a good method for material control. Running stock on edge with a 4" tall fence and no pressure device is not something I can do.

I don't have a shaper so I can't speak to the speeds but if you are running router bits in the shaper, I assume router speeds would be used. I would run a 3/8" core box at over 20,000 RPM. Does your shaper approach these speeds? If not do you have a router table available?

This (http://www.tegstools.com/pdf/tips/speedchart.pdf) may also help(?).

[Matt Tawes]

Good suggestions Glenn. I don't use a shapper either but prefer the router table and feel its more versatile. Its true that the slow speed or lack of adequate support may be causing his tearout. I've seen it done and read where running the profile as a climb cut (backwards) alleviates tearout in some tricky woods but sure is danerous and can result in more damage to you or the piece if not supported and done very carefully (like the bit snatching it out of your hand and shooting it across the room).

[denis tuomey]

Thanks for the help, I did make a 4" fence and used feather boards to help hold against the fence, the cutter is brand new Freud. The raised panel cuts across the grain did fine, as did the cope in the rail ends, both these were done with horizontal cutters. My Jet 1 1/2hp. shaper only has a top speed of 9000, maybe speed is the answer. Guess I'll check the speeds on my Sears table top router/shaper-maybe that will work

[J.R. Rutter]

I don't know exactly what type of cutter geometry you have, but I do all door edges with the door flat on the table and the cutters above (though face down would work as well). This way, the sharp edge of the cutter is slicing the end grain on the stiles. With the cut running vertically, the end grain will be lifted by the cutter, sort of like a table saw blade will tear out on the bottom of the cut on cross grain.

[denis tuomey]

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[denis tuomey]

After seeing that my Sears tabel mount shaper/router only has a top speed of 10,000, I went and picked up a Bosch bench mount router table and mounted my PC 690 in it(which has 27,500 rpm). :) That did it! SPEED WAS THE ANSWER! I ran the same piece that tore out real bad thru about 6x and got a nice clean cut each time. Now all I have to do is re-make the frames and drawer fronts and run em thru. Live n Learn, thanks for everyones input.