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View Full Version : Segmented Bowl chip and tearout



Dennis Dearborn
02-28-2010, 6:06 PM
I've made quite a few bowls and had some pretty good luck, but lately they seem to chip and tearout like crazy. My latest ones are made of cherry, walnut, maple, and oak. The oak chips and tears terribly. I've just discovered that a sharp scraper works better on the outside than a chisel. The question is, what angle do I sharpen my chisels to. I've heard everything from 25 to 40 degrees. I had no trouble making give aways, now that I've found a place to sell them everything is going downhill.

Dennis :confused:

Bernie Weishapl
02-28-2010, 6:35 PM
Dennis I am thinking that those figures are for spindle gouges not bowls gouges. My bowl gouges with the Irish grinds are somewhere between 50 deg to 60 deg and I just measured 54 deg. My conventional bowl gouge has a angle of 45 deg. Are you using a spindle gouge or a bowl gouge on your bowls? Can you show of picture of the gouges you are using? That would help with some answers.

Wally Dickerman
02-28-2010, 6:42 PM
I grind most of my scrapers at 30 deg....60 if you measure the other way. If it's a little more or a little less...doesn't matter.

I suggest that you try using a negative rake scraper and try to go with the grain. If you don't know what a neg rake scraper is, try a skew chisel laid flat on the tool rest. The handle should be level and take light cuts.

You might also try shear scraping. We've had some threads on that. Again, go with the grain if you can.

Wally

Dennis Dearborn
02-28-2010, 10:10 PM
THanks for the quick reply. I am using a 30 degree angle on the scraper, maybe that's why it's working pretty god.

I will try to get a couple of photos of my chisels up soon. One is a roughing chisel about 3/4 wide. The other is a pretty good bowl gouge about 5/8 wide. It's the one that has a lot of metal on the bottom, not a bent one. I could try 55 degrees on another gouge before I regrind my good one.

Dennis

Bill Bulloch
03-01-2010, 8:49 AM
I use Cabinet Scrappers on both the inside and outside of my segmented bowl. They leave a clean, smooth finish and you can starting sanding with a higher grit (I start with 150 grit most of the time). They work to clean up tear out also.