Sanding Forever

apply a thick coat of wax to the bad area and stick to 80 grit until the pits are gone

First rule of sanding is that the next grit will never take out what the current one left. If you haven't got the gouge working properly yet, you're going to want to start coarse, and you're going to want to pay special attention to the area just after you exit the end grain (two places) on a flatsawn bowl. That's the place where you pull out some fibers as the edge attempts to cut them unsupported. Since you know where it's worse, you could perhaps begin with special attention to that area. Wet the surface. No soak, damp (water) rag will do. This is a reveal, as the torn fibers will show as dull, and a help, because those you crushed will stand up and give you a chance to catch them proud, rather than having you go down to their level, with the burnished rings mocking you all the time. I don't like the self-powered type of sander, but regardless of your method, sand for a uniform background, then run another reveal. If the tearout is still there, let it dry and have at it with the same grit.

Rule number two of sanding is you are sanding with the prior grit unless you clear all dust before changing to finer. Especially with softer back papers, grit kicks off, gets temporarily embedded, or hides until it's caught by your next one. Then it makes an ugly irregular scratch. If you use the reveal/set between grits, you can beat this one, too. One other note, sand on the downward moving side so the dust clears by gravity. No sense heating by rubbing dust you've already removed into the area, and dust collection at bottom rear is a lot easier. You can see the stuff leaving the edge. Not to mention the reduced danger of finger stubbing. Also makes sense to sand in, wipe out so you don't waste time rechewing the dust held to the surface by centrifugal force as you come from center outward.

Rule number three is - heat is the ENEMY. Don't try to speed things up by pressing any more than it takes to maintain contact. Heat is bad for the glue on the grit, the glue to the backing when using velcro types, and the wood. Especially the wood, because it heats and hardens, looking nice and shiny - except for a few scratches which you just can't get out. This is called burnishing or case-hardening, and is also vulnerable to the water set and reveal. It's this condition the advocates of wax, or oil or mineral spirits are trying to avoid by keeping the surface lubricated, reducing heat. It comes at a cost, of course, if your selected finish isn't compatible, or if you don't care for the look of stuffed pores - because it will stuff the pores of the wood with the dust/oil mixture and cut down overall brilliance. Open coat, stearated papers can help here.

I have the same problem with most of the bowls I turn. Two ways to fight it and one way that just doesn't work at all.

Way #1 that doesn't work Just use your self powered sander or a powered sander. It seems they sand around the bowl but never touch those torn areas. You can just about sand forever with 80 grit and never get anywhere. I believe that the change in grain causes the paper to jump over the torn area because #2 works. Way#2 Stop the lathe and sand with a powered sander. Just do the areas with the torn grain which will sand away and then go back to the lathe spinning to even out the depressions you made. Way#3 Probably the best way. Use a material to stiffen the torn grain. (see other replies too) You can use water, wax, sanding sealer etc. I like wax. I heat wax and then add about half the volume of turpentine. This softens the wax and allows it to penetrate the torn areas. I then turn the lathe on and use some 60 or 80 grit paper. It will fill up with wax but just brush it off or keep sanding since it will sand through the wax buildup to some extent. By the time you have removed most of the wax the torn grain will be gone. If some remains, just apply more wax and keep sanding. This cuts the time to sand out that torn grain by 523% or so. Also the dust will be in the wax and not all over. Then blow off the piece and go to the next grit. Don't go to finer grits until all the torn grain is gone.

Greg in Oshkosh

Thanks for the suggestions. I'm glad that there is only 3 rules George.. too bad I had to break all of them :( Live and learn.

Cheers, Tom

This is gonna sounbd sarcastic...but...is isn't....

You forgot way #4....and that is to use the appropriate tools and technique to cut the wood fibers cleanly so you don't have any, or as much, tear-out to deal with. When you have to sand the tear-out...what really happens is you have to sand the surrounding wood down to the depth of the tear-out...and that could be a LOT of wood to take out with sand-paper. Much easier and faster to do it with a tool. Even if you leave ridges. It's easier to sand out ridges than tear-out.

Greg Kulibert wrote:

Sure is better to cut than sand. And it's ridges over pits for me, too. One pass with the disc cutting at 11:00-1:00 (~90 degrees) can clean them up, and it's all under power, and supported, so I don't dish out certain areas of the piece.

Which leads to a sanding truth - sometimes it's easier to start with a finer grit than to spend time getting out the marks left by a coarser.

Learn your tool angles, Tom, and that'll be the only decision you'll need to make.

The trick here is to never jump more than two grades at a time. If using =

60 grit first, don't jump to 120, use 100 next.

The problem I had was that the bowl is about 4" deep and 8" wide, held by aTallon chuck on my Jet Mini. So far, I have a 3/4" and 3/8" shallow gouges and, when I attempted to get into the bottom of the bowl with either of these tools, the end of the tool handle contacted the lathe bed and I would start to get catches. Obviously there is a workaround and a technique for this but I've yet to learn it. (I'm reading Raffan's books but it is a steep learning curve). So, I used a 3/4" round nose scraper to hollow the last of the bowl. Getting the tool rest in the proper position for leverage was also a challenge. I didn't have good control over the tip of the tool because the fulcrum was quite far back.

As I intend to keep at this bowl thing until I get it right, I would like advice on what my next tool purchase(s) should be. Gouge - spindle or bowl? size? grind? Scraper - flat nose? round nose? bevel?

Thanks far any suggestions. Tom

Listen to what Randy and George have said especially. You will find that as your skills increase you develop better tool technique that will minimize or eliminate the tear out. You'll also learn methods to deal with it when it does (inevitably) occur occasionally. As you get better at sharpening your tools, learning to cut with the grain, shear scraping technique and final shearing cuts, you will experience less tearout. Very occasionally I will wind up with a finish that really could get by with no sanding at all, but I always sand some anyway.

Until you develop these techniques, and mostly only time and learning from another turner will teach them to you, there are ways to deal with tearout. Some of them have been mentioned already.

I find it very beneficial to treat an area with tearout prior to sanding or final shear scraping. My treatment method usually involves firming up the grain with sanding sealer, shellac, CA or lacquer (even yellow glue will work). Once the grain has been hardened with one of these treatments it can often be turned very cleanly with light cuts, or sanded out very quickly. Some find that oil or even WD40 work great for this purpose, but I have not.

I also have a few tools that I reserve specifically for final shearing and finishing cuts. These get sharpened to a razor's edge and honed, and used only for light finishing cuts. It helps immensely, but a light touch is a must.

Eventually you'll know just what to do on those occasions when you see tearout, and sanding forever will not be one of those things.

Hi Tom, Shear scraping can go a long way to removing a lot of the tear out. Sharpen your round nose scraper so it has a fresh burr on it. Place the scraper flat on the tool rest, and now rotate (roll) it 45 degrees. Take very, very light passes. You should get very fine shavings coming off the tool. I'll admit it is difficult to control across the bottom of the bowl, but coming up the sides is much easier. It will take many passes as you are taking off very little material at a time, but it can be faster than sanding, and you don't have to worry about heat checking, case hardening or burnishing the wood. It would be good if you can get someone to show you this technique, and/or practice it on scrap first. A bowl gouge would be nice, but people do make bowls without one. As you found out, you can hollow a bowl with a scraper, and a freshly sharpened scraper can be quite aggressive. If you decide on a bowl gouge, get a large one 1/2" to 3/4". Tool rest position - on an 8" bowl on a Jet mini lathe, you should be able to position the tool rest so that the far corner is actually inside the bowl. This will get the rest a little closer to the bottom of the bowl. Hope this helps. Martin

Use a bowl gouge (aka deep fluted gouge) instead of the spindle gouge (aka shallow fluted gouge) and you're not going to have so many problems. The bevels and geometry of the bowl gouge tool will greatly help (but not always prevent) here. I use the shallow fluted gouges on a great many types of bowls and vessels but from what you are describing, that's not a place where even I'd be using it.

First, if you can, look at a video on bowl turning . Most are far better than any book with picture and especially trying to describe it. Even better to find someone that knows what they're doing to actually show and help you. There's nothing like seeing it first-hand.

Second, from the way you describe it, you're putting quite a strain on that scraper. The scraper is a great tool but, at least in this case, you're going to want to use it only for the lightest finishing cuts and not really hogging it out. Like I said, this is what I'm inferring from what you said above. Maybe you're not doing that in reality though.

Third, yes, having that toolrest too far away sets you up for problems with about any tool. Try to get it (safely!) closer to where the tool is contacting the wood and you'll get smoother and more controlled cuts. There are many makers of curved toolrests or you can just make your own too. They work great.

Without a doubt, a bowl gouge. 3/8" - 1/2" is fine for basic bowls in the

4" - 14" range. Don't worry about grind. You'll change that and adjust it to suit your needs (and sharpening technique?) too. A nice, thick (1/2") scraper of, say, 3/4" - 1.5" wide would be good too. Round nose. Again, don't worry about the bevel when you buy it. It's AFTER you buy it and try to get a good edge (or burr in the case of the scraper) is when you need to develop the knowledge and skill of keeping it that way.

Good luck and keep asking questions,

- Andrew

Tom, For any gouge to cut to the center of the inside bottom of a bowl without the handle hitting the rim, the bevel needs to be nearer to vertical than flat. ie. a short bevel, maybe 60+ deg. to the flute. This allows the bevel to rub all the way to the center as the handle, being more perpendicular to the bowl's bottom, stays away from the edge. Arch

Fortiter,

I would definitely recommend you get a 1/2" bowl gouge. I use a Crown PM

1/2" gouge and always sharpen it in a fingernail grind with a similar jig to what Darrell Feltmate shows at : I can sharpen very accurately and loose minimal gouge length using this simple wood jig. Also, I recommend you shorten the bevel on the nose to approximately half the normal length by grinding a second shallow angle bevel at the heel. This allows much smoother cutting of inside curves. Some people recommend a 3/8" or 1/4" gouge, but most production turners do not use such a light tool. I bent my 3/8" bowl gouge several times. I was learning, but it still bent too easily for my taste. In certain circumstances you are cutting far over the toolrest and the extra heft is very helpful. I'll make a few hundred bowls this year.

I would strongly recommend you buy a woodturning video. I don't have a nearby club and I have learned what I know through videos and this newsgroup. You just can't see the motions and the description on paper like you can on film.

Derek

Arch, the bevel will always rub where it's been, because wood's been taken off to permit it. Take that flat gouge, roll it on its edge, then tilt the handle down about 15 -20 degrees, and you can cut continuously rim to button. Are you caught in conventional thinking as one who only sees a bevel as perpendicular to the edge, or can you visualize that a bevel also rubs parallel to it? Take a peek, followed by a think, at

for anexample. Deepest point of the cut, where the gouge exits the wood, is cutcleanly, nearly perpendicular to fiber direction. Initial wood is removedby a near scrape to make room for the bevel-supported cut.Since the handle never goes more than a couple inches below centerline, noproblem with interference from the bed, and for the wheelchair turner, noneed to take the shock along the length of a bowl gouge turned point up.The force of the rotation helps hold the gouge firmly to the rest, allowinga smartass instructor to make the cut one-handed, one of the few things thatimpresses teenagers who think they have to white-knuckle their way through aturning.

George, I looked at your pic while thinking about your explanation and both seem valid. I don't want to be stubbornly conventional, but I've used a short (steep) bevelled gouge in order to bring it to the center of a bowl for so long that I've got to wait til the one martini I'm permtted before dinner wears off before I give in and fully agree. :)

The bevel on your pictured gouge seems to be reasonably short. I was thinking of a somewhat longer and swept back bevel, and I'm trying to visualize if that makes any difference re using your method. Thanks for the probable correction, I'll try it your way with a long swept back gouge tomorrow. Regards, Arch

Fortiter,

I just bought a Sorby Hollowmaster. I got it because I was spending too much time sanding deeper vessels. After I get my bowl gouge in to the point I can't rub the bevel I pull out the hollowmaster. Still learning to use it and it is great. Really cuts down on the sanding.

Tremendous response folks, good to know that such a wealth of valuable info is available on this NG. Thanks a bunch.

Tom