Avoiding tear out on end grain while turning outside of bowl

[Kris Langohr]

I have started turning some small bowls from blanks purchased at Woodcraft. I can get the form much to my liking but I am running into a lot of issue on the endgrain sides of the outside of the bowl. The 2 issues I have are:

1) Avoiding tear out to get a consistently smooth finish all the way around

2) Finding a good finishing technique that gives a consistent appearance on all sides of the form

I suspect that fixing my problem with #1 will help with #2. Anyone have some good tricks or tips for helping to prevent the tearout on the end grain sides of a bowl? It is possible that I am just not getting my gouges and scrapers sharp enough to cleanly cut but on the last bowl I did tired to be more aggressive in making sure to resharpen a little more frequently. Is there a particular type of wood that is less prone to tearout? Are there ones that are more prone (maybe I keep picking those)?

Any suggestions anyone has would be greatly appreciated.

Thanks,
Kris

[Neil McWilliams]

Yes your tools should be freshly sharpened. Be sure your cutting edge is at the equator of your turning. Try shear scraping.

[Roger Chandler]

Freshly sharpened tool for the final passes and a shear cut.............if you don't know how to do that technique, you should ask an experienced turner in your local club to show you how to accomplish it........good luck with your projects!

[David E Keller]

Make sure you're cutting with the grain... Small to large on the outside of a cross grain form... Large to small on the inside. Light cuts help at times. Soaking the wood with oil or shellac before finishing cuts can help as well. Nothing helps more than a sharp tool though!

[Steve Kubien]

I have never heard of a turner having this problem before. Nope, not one. Certainly not me!

Ok, now that I have gotten the bull out of the way, you haven't really given us a lot to go on here. Could be your sharpening (or lack thereof), could be the wood (species? Grain? Degree of punk/rot?), could be height of the tool rest, could be speed... The tough thing now is, figuring out what to tell you.

Sharpening and profile of the gouge is the first place I would look...

[Dan Forman]

220008

This is how I usually deal with tear out on the outside of a bowl. It's a 1 1/2" negative rake scraper (I added the negative rake). I have a matching pair, one slanted right, one left. This is the right one, but actually I would use the left one on the outside of a bowl. The point will get right up next to the jaws at the base, then I do a pull cut to the rim. If there are waves that need to be taken out, or tool marks cut into the wood, I stay at one place on the tool rest, and pivot the tool back and forth, working from one side of the tool to the other, which will take down the area without making a big flat spot. The surface left is usually very clean, with no tear out. I find the wide edge much easier to get a sooth surface with (no ripples or grooves) than any bowl gouge. The negative rake both cuts cleaner than a regular scraper, and takes a small bite, so it's its for cleaning up, not hogging. It can be used flat on the tool rest, and the handle can be parallel to the floor. It needs to be used with very light pressure if the bowl is thin enough to cause chatter.

Dan

[Wally Dickerman]

Providing you're using solid wood, not punky, there is no good reason to have end grain tearout on the outside of a bowl if...you are using a sharp tool (ever try to whittle a stick with a butterknife?), if you are rubbing the bevel of the tool on the wood, and if you are cutting WITH the grain of the wood.

A little bit of shear scraping to get rid of the slightly uneven surface left by the gouge Then, if you do all of that you should be good to go with 180 grit sandpaper....

[Bernie Weishapl]

Have to agree with Wally. I do use a vertical shear scrape with a freshly sharpened gouge like Bill Grumbine or Mike Mahoney which will leave a level smooth surface.

[Kris Langohr]

Thanks for the advice everyone. I can see several things mentioned that I am probably not doing the right way. I will give a few of those a try and see if it helps out. My guess is that tools that are quite sharp enough and not going with the grain are my biggest issues here.

Thanks,
Kris

[Mike D Harris]

Hi, I'm having similar problems, and since I've only been turning for a few days I'm having trouble knowing when the gouge needs sharpening. I bought a Thompson 1/2" V gouge and am making 6" bowls out of freshly cut red oak. Can you give me an estimate of how often I should be sharpening? Is it x sharpenings per bowl or x bowls per sharpening? :) Thanks.

[David E Keller]

Hi, I'm having similar problems, and since I've only been turning for a few days I'm having trouble knowing when the gouge needs sharpening. I bought a Thompson 1/2" V gouge and am making 6" bowls out of freshly cut red oak. Can you give me an estimate of how often I should be sharpening? Is it x sharpenings per bowl or x bowls per sharpening? :) Thanks.

I tend to sharpen when I feel it's needed or for finishing cuts. With a little time turning, you'll be able to feel when the tool needs a touch up. Just a guess, but I'd probably sharpen before and at least once during a six inch oak bowl... The second time might not be necessary or it might require another depending on the wood. The few seconds I spend at the grinder would save me at least several minutes with the sander.

[Mike D Harris]

Thanks. I don't mind sharpening, but I don't want to needlessly wear away my $62 super-metal gouge. :) That's about how often feels right, so I'm on the right track.

[Bill Wyko]

Check out this site for negative rake scraping. I just did pa platter that was rather punky. I used my Mini scraper upside down and it worked great. Go to www.negativerakescraper.com (http://www.negativerakescraper.com). Some really good info there.

[Mark Levitski]

In general, and for end grain in particular, on the outside of a bowl I have much better results with a shear cut and not a shear scrape. I am talking about using a bowl gouge with a long side-grind. The gouge is held handle-down leaving the cutting edge of the wing about 45 degrees or more to the wood with a fine pull cut. Start with it nearly vertical and then engage it with less angle as you need. Vertical edge is safe and equals no cut, less and you begin cutting. That means the flute is facing toward where you are pulling and the bevel is rubbing. It is similar to the shear scrape but the flute is rolled out and facing the direction of the cut instead of facing the wood.
The bevel of the cuttng edge rubs using it to cut instead of scrape. Grumbine calls this a tangent cut I think. To me it is like using the edge of the gouge like a skew yet with lots more control.
Experiment and you will discover it. Or try Grumbine's video (I don't have it. I read it somewhere in the web.) Ellsworth describes something similar in his book. I have that. Better yet, get with someone local to show you some things.