Sandpaper scratches on turnings?

Re: Sandpaper scratches on turnings?

Tony Reynolds

>According to some, you don't need to sand if turned properly. Now for the rest of us. If doing it by hand it's tough to do but you need to keep the paper moving all the time so as not to get circle scratch marks. Lots of folks use either passive or power sanding which is a sanding disc attached to a drill of some type. The passive ones use the rotation of the object to power it. I'm sure you'll get other ideas posted as well. Have fun and be sure to post a photo of the platter for us to see when finished.

Tony

Re: Sandpaper scratches on turnings?

Barbara Gill, Remlik Virginia

>Sanding can get sort of complicated. I have found that scratches left for me are usually those from the first paper I started with. I spend the most time with the first two grits making sure there are no deep scratches. I also carefully wipe the piece well between each grit so that no stray grit is left from one to be rubbed in the wood by the next.

Re: Sandpaper scratches on turnings?

Wally Dickerman at Green Valley, Az.

>I agree with Barbara. After you've sanded with the heaviest grit, which is intended to remove all tool marks, torn or damaged wood, the following grits are only to remove the marks from the previous grit. A couple of things...Don't skip grits. I don't know what grit you start with, but grits should run 80, 120, 150, 180, 220, 320, 400, 600. You can go higher than that, but most don't. If you'll sand with oil, at least with the first couple of grits, it will help a lot. I use regular finishing oil, but mineral oil works fine. Don't worry about the oil affecting the finish, because it won't.

Wally

Sandpaper Scratches on jTurnings

Dennis J. Gooding

>Barbara is dead on regarding the first few grits being the critical one. One other important thing; if the piece is worth sanding, it is worth using a new sheet of paper. When I have trouble, it is almost always because I tried to stretch a worn-out piece of sandpaper. (Worn-out 120 grit WILL NOT remove the scratches from worn-out 80 grit.) :~)

Dennis

Re: Sandpaper Scratches on jTurnings

John Lucas

>Nobody has mentioned what I consider the most important part. Lighting. Theres also dusting. If you follow the other methods mentioned your on the right track but without proper lighting you can't see the scratches. The small scratches also get filled with dust and won't show so blowing them off or use a brush to get the dust out between grits.

I have 2 100 watt lamps mounted on my lathe. When I sand I turn one of them off and adjust it to an oblique angle to the area being sanded. This shows off the scratches and you can start sanding with the next grit. Some woods are simply harder to sand than others. When I notice I'm having trouble seeing the deeper marks I'll sand with about 3 grits higher. I'll do this lightly. It shows off all the deep scratches and tells me where I need to concentrate.

I use an air compressor to blow the wood off between grits. This does 2 things. It clears the dust out of the scratches so it shows better and it also gets rid of the grit from the last paper. For example you start with 120 grit then switch to 150. Sometimes you'll have grit from the 120 still on the bowl and it will be pushed around by the 150 and leave deep scartches. These may even be picked up by the 180. Blowing or brushing the wood between stops this.

Don't know if you all agree with this but it works for me. I did have some soft maple that had what looked like sanding scratches even after going through all I mentioned above. It was spalted and getting punky. I wonder if I was pulling fibers out and what I was seeing was this instead of sanding marks.

Re: Sandpaper scratches on turnings?

Jim R

>You have had some good advice here and here is mine. I have done lots of sanding because I am not expert enough to turn a perfect finish. Here is my advice. Sand slower than turning. Giving a lathe speed is a little hard because the size of the piece will effect that but I sand pretty slow. Start with the finest grit that will do the job. I have started with 60 grit on some pieces and some with 150. I can't tell you how to judge that, its just experience. Keep the sand paper moving prevents lots of really deep scratches, especially on coaser grit. DO NOT use heavy pressure on the paper. This goes for all grits. Unless I have a really bad spot I do not put a lot of pressure on the paper. Clean the piece frequently-If you don't you are only sanding sawdust. I use my shop vac with a brush each time I stop to check the surface or change paper. If possible, before you change grits, go over the piece WITH the grain. Lots of times this is not possible but it does help. If you can do this, you can see the circular scratches disappear. This is a must when turning pens and it really helps. As you go to finer grits try using less pressure. You are not removing as much wood and a lighter touch will suffice.

Remember, all sand paper leaves scratches, you are just trying to get to the point they are virtually invisible to the naked eye. Going on up to finer grit for the final surface is the key and how far you go is up to you. For me I think that 500-600 is as much fun as I can stand. Sanding is not as much fun as turning.

Re: Sandpaper scratches on turnings?

Leo Van Der Loo

>Roly, you have had a lot of good advice here, the one thing that I want to stress here is use very good quality paper, or the dang grit will come of and make for some bad gauges, the next is make sure you clean that platter well before you go to the next grit, last, some hand sanding with the grain can give you less lines going around and around,

Have fun and take care

Leo V

Re: Sandpaper scratches on turnings?

Roly (So Cal)

>Wow, what a great turning site, ask a simple question and I get 14 tips from 6 responses. Thanks, Tony, Barbara, Wally, Dennis, John and Dennis. I look over this list and I have been doing none of them! My previous sanding attempts involved digging through my used sandpaper box, pushing hard in the same place with worn out paper at a high speed. Never have dusted or blown off with air, don't even buy grits over 200, always sand dry with no oil and never considered the importance of proper lighting.

Other than that, I have been doing everything right, except, Tony, I guess I have never turned a piece properly, because they ALWAYS have to be sanded, (and it looks like I have been doing it incorrectly every time).

Thanks for the great advice, guess I better start attending turners meetings to get some education, (after being a carpenter for 50 years).

Roly Nelson, so much smarter than before....~~

Re: Sandpaper scratches on turnings?

Tony Reynolds

>And neither have I Roly, and never will!! :)

Re: Sandpaper scratches on turnings?

Steve Mushinski

>Roly,

220grit is fine sanding with the grain but with turned wood you are not sanding with the grain if you have the lathe running. Therefore you must sand with higher grit paper. Depending on the wood I would say 400grit is the roughest paper to stop at. With hard exotics like cocobolo I go to about 3000 grit to get the scratches out.

New paper is another must. After that the best advice is "light". Take a piece off the lathe and rotate around by hand bouncing the light at different angles and you will see the scratches.

Re: Sandpaper scratches on turnings?

Roly (So Cal)

>Thanks Steve and Leo, now I have a bunch of sanding info that I must practice on. I went to our local Inland Woodturners meeting today and was shown tricks in putting a fine luster finish on my work. Now off to buy some buffing wheels, and various grits of buffing compound...where does it end?

What a great hobby, sure beats sitting on the couch all day drinking beer and watching TV.

Roly, still anxious to learn, no matter what age!