Bowl Turning Tear-out Problem ? ? ?

Hi Barry. The easiest way would have been to rough turn the blank a year ago. It would have been dry by now and would cut a lot better. Wood dries at a rate of an inch per year plus a year. At this point a coat of wax on the area will make the fibers of the wood stiff enough to cut. A coat of lacquer, shelac or sanding sealer will also work. And as always keep your tools as sharp as possible when your nearing final thickness. Bob, Naugatuck Ct.

Hi Barry, Everything the others suggest is true. Another option that helps when you just can't seem to get rid of that last bit of torn endgrain while turning is to try wax-sanding. I read about this tactic on the newsgroup about a year ago. I remember Ruth mentioning trying it. A couple times recently I've had to resort to it to help remove the torn endgrain and it works. You might have to reapply the wax once or twice to the area, depending on how bad it is. I was doing a demo for the 4-H over the weekend at the county fair grounds. And I had a small piece of willow to make a bowl out of. And no matter the tool or the cut I just couldnt get rid of all the tear-out. Some woods are like that. So I put on some wax in the problem area, and a little sanding and it was gone. --Jim M.

Hello Barry,

Here are a few things to try:

1. Apply sanding sealer or the finish that you will be using. This will cause the fibers to expand; they will be in a better position to be sheared rather than "plucked". Let the sealer/finish dry overnight and the fibers will stiffen and stick together; again, more likely to be sheared crisply. Sometimes paste wax is enough to make the difference.

1. Try a freshly sharpened bowl gouge and cut the fibers cleanly rather than scrape. Cherry is only medium hard. The harder the wood, the better results that you will get from a scraper.

2. There are even 2 part epoxy finishes, Polycryl and even thin CA adhesive as are used on spalted wood but those should not be necessary for just normal dry cherry.

I would much rather spend a few seconds sharpening and taking a fine, finish cut with a bowl gouge than many minutes sanding!

Hi Barry, It's implicit in the good advice you 've gotten, but remember to work the _problem. ie. when cutting or scraping fails, stop the lathe and seal, oil, wax or wet the paper and the two torn areas and sand _only those bad areas_ til smooth. Then feather out. Hope you don't 'save' by using worn out or cheap abrasives. Sometimes sterate paper works better than open grit. Try holding the paper in your rt. hand and rocking the piece back & forth with your left hand. Sometimes reversing the lathe's rotation will bring those surly fibers to attention and they can be cut or sanded off at the knees. ;) Now clean up by gently shearscraping with a heavy sharp tool. Sometimes 'floating' the shearscraper by holding it unsupported off the toolrest helps. Higher speed seems to help me. Sometimes, for me, nothing helps except to re-turn the interior or to 'decorate' the torn grain area! Remember those 'soda straws' and finish cut cross grain interior surfaces toward the center. I think the $5 word is centripetal.;) Finally, there may be a place for LDD in dealing with this problem.

Recall that there are ways to hand or power sand most bowl interiors other than with discs, ex.: flap sanding by holding small strips of the abrasive in a slotted dowel. winding the paper around a dowel or stapled over a domed pad, etc. Arch

Fortiter,

Barry,

I just turned a >wet

I turn a lot of cherry, and it seems no more prone to tearing than other domestics, perhaps it's just more noticeable.

I suspect it happens where you're turning the corner between wall and bottom. That's where I have the problem. I found out early that a scraper was _not_ the answer. If it's a steep transition, and I suspect it is because you said you couldn't power sand the area, the best I've found is to use a pointy gouge or the narrowest bowl gouge I own, freshly sharpened, beginning in the wall area, cutting point and left, rotating clockwise through the transition to cut point and right. Two things you want to avoid are riding the tool on the wood, where it might crush the fibers at the early/late transition areas, and _ever_ cutting nose up. The nose of the gouge should be as close to vertical as possible, making the shavings tightly coiled. Your description of "short curls" tells me you're cutting nose up, where you take a shaving on face grain, and break it on endgrain. This is more or less normal for some brittle porous woods like oak, but cherry and other short-grained woods give continuous curls to a properly placed gouge. As a matter of fact, I have to watch the finishing cuts on the opposite side of the bowl, because the shavings accumulate in a huge mat at the gouge.

If the transition is not so steep, I love a flat forged gouge for the final pass(es). With a steady, even thin-walled turnings can be cut continuously, though you have to take care not to dig in near the center. Best to leave a button to scrape or sand.

As to saturating the surface fibers with this or that, I have no experience. The first time I examined the torn areas, I figured out it was caused by picking up the ends of the fibers with a gouge cutting too broadly and nose up, and modified my technique to cut a narrow face at an angle that cuts through rather than pulling up the fibers. I never plan any particular finish in advance, which means I might make a bad choice of what to use to set up the fibers, so the only set is the one between 180 and 220, and that with water.

The shape of the bowl in this area of tear-out eliminates any

Thanks for the help. Actually, I'm using stearated paper. In my estimation, the surface that I have is not ready for sandpaper.........even

80 grit. It still needs tool work. Its not so much fuzzy fibers on the surface as it is pits that need to be leveled out by recutting.

I had tried most of the advice already. I finally re-sharpened my new Sorby shear scraper (just because its new doesn't mean its sharp!). I made a couple of passes with the newly sharpened shear scraper and then re-sanded. Its acceptable. Not as good as I would like, but passable. Maybe I'll do better next time. Thanks.

Barry

PS My Jet Mini won't reverse.

How do I get rid of the tear out? Any suggestions will be greatly appreciated.

Well, it is not using a turning tool, but in a former life (as a regular woodworker) I had a lot of success with cabinet scrapers - you know those flat pieces of metal with a small burr raised on the edge. They make some that have a curved edge on them, and although it may be cheating (grin) I have found that they are often my best bet for removing torn grain on the inside of a bowl. I had some poplar (I know, I know - but it was free) that I was using to turn some bowls and practice thin turning with and the chatter and tear out was really tough till I tried the cabinet scrapers. Hope this helps!

Sawblade

Been there, done that! Watch out for catches! Wear gloves and turn at low speeds!

I guess I am just too impatient! *G* Actually, I haven't done any inside the bowl scraping in a while. I still use cabinet scrapers on the outside of the bowl occasionally.