Sanding Turnings?

[Kevin Gerstenecker]

I have a question that has me rather perplexed. I have noticed on a couple of Bowls I have turned, I have not been able to get the End Grain portion of the bowl sides as smooth as I think they should be. I notice this on some species of wood more than others. For instance, the Locust I turned seem to sand and finish beautifully on the end grain areas. The Walnut I have turned seems to be OK too, but maybe it could be a little better. Where I have notice the problem most is on Cherry. I smooth the bowl exterior sides the best I can before I start the sanding process. I start with courser grit paper and work my way thru the various grits to 1000 or 1500, followed by a synthetic 3M pad. I usually run the gray pad, followed by the white. The side grain portions seem to come out as smooth as silk, but the end grain areas are frustrating me some. It is still somewhat rough, and "cloudy" looking, if that makes sense? Is there something I am missing, or does anyone have any suggestions? Being a rookie, this is starting to get under my skin a little. Thanks in advance for any suggestions or help! :D

[Dennis Peacock]

Kevin,

Cherry has proven to be a "toughy" for me as well. I can get most all of it glass smooth except for the end grain. I know of no tricks and am willing to learn what it will take to make the cherry end grain feel and "look" smooth. Let me know what you find out.

[Ernie Kuhn]

Guys,
I'm wondering if a little grain filler would work on the end grain. I have no commercial interest in but have used, Bull's Eye Seal Coat a couple of times for problem areas with some degree of success. Once you get everything else as smooth as you want, might try wet sanding with Seal Coat and see what happens. Just a thought. If that doesn't work and you find what does, please let me know.
Ernie

[Tom Sweeney]

could probably use a little more sanding - but I'm too impatient to go as high as you do. One thing I do though is to burnish the turning with shavings. Do you do that? You grab a handfull of shavings & rub it into the piece as hard as you can with the lathe spinning on low speed. Careful! It do get hot :eek: It seems to really smooth certain woods out. It worked real well on the cherry I just did last night. I've heard of people using brown paper bags also.

Also try your final sanding with the piece oiled, unless you already do that.
Just some thoughts from another newbie.

[Bill Howatt]

I find that tough end-grain sanding can be helped by wet sanding. Go back to about the 400 paper and wet the piece with mineral oil or sanding sealer and sand while wet. You will notice a slurry of the sawdust and oil forming on the paper.

This will work with both hand sanding and power sanding.

If your lathe is reversible you can try sanding in reverse to see if it helps but be careful the chuck or faceplate or... doesn't unthread! Tighten it well first. The sanding forces aren't usually too great to cause loosening but it is not impossible.

Bill

[Jim Becker]

I find that power sanding with "wave" disks really helps take care of most of this kind of problem. If it doesn't, you need to cut with sharper tools or use some wax or thinned finish on the spots where the gouge hits the endgrain to reduce or eliminate the tearout.

For power sanding, I use a Souix angle drill and either the 2" or 3" "wave" sanding disks, usually with a soft pad unless there is a soft/hard grain situation. A harder pad is appropriate there, just as was discussed in KC's thread about sanding his chess board in the last day or so.

Hand sanding is sometimes difficult to do when you need to remove tool marks and some minor tears and it can also add it's own scratches if you are not careful. (Always wipe the piece down between grits whether sanding by hand or with power)

[Richard Allen]

Hi Kevin

Whne I have an endgrain "issue" I go back to the tool. (that might not be posible if the bowl has been dismounted). I sharpen the bowl gouge (actualy pick up a second bowl gouge that has a fresh edge) and I try a light pass with the tool. If that doesn't improve things I wet the end grain with water and make another light pass. If that doesn't improve things I wipe a little quick drying film finish on the end grain and make another light pass.

If I see improvment on any of these I switch to a shear scrape and work with light passes till the tearour appears gone. I say "appears" because there is a good chance that when sanding the tearout will become visible around 320 or 400. When the tearout shows up I will drop back two grits and hand sand the problem areas. Then proceed with normal sanding from that grit.

Sometimes I will power sand a spot of tearout if the hand sanding doesn't work. This will leave the surface uneven but tearour free.

It is also a good idea to slow the lathe down when sanding. This is especialy true if the tearout appears (clockwise) after the absoulut endgrain. This is because on some woods the endgrain will push the sandpaper away from the spinning woodand you end up "skiping" past the problem tearout.

Even with all that effort I still get tearout from time to time.

Good luck and let us know what ends up working for you.

Thanks

[Bill Grumbine]

Hi Kevin

I see many of the responses have dealt with various sanding techniques, and in some cases that may be all that is needed. I show my students a shear scraping technique with a sharp bowl gouge that helps the process along quite well in most cases, even on the inside of the bowl, which I presume is the location of the problem.

Shear scraping is sort of difficult to describe in words, but in essence you hold the gouge parallel to the ground, with BOTH FLUTES TOUCHING the wood where you want to cut. Notice the empahsis I place on this. If you do not do this correctly, you will experience a very dramatic catch which will scare you right out of ever wanting to try this technique again. Once you have both flutes rubbing, ease the top flute away from the wood so that it just breaks contact, and the bottom flute will start to produce very fine shavings with some dust. The danger in this cut lies in letting the top flute drift too far away from the surface of the wood being cut. How far is too far? I can't tell you quantitatively, but the tool will let you know in a very dramatic way.

Draw the gouge towards you along the surface of the wood with light, yet firm passes. You can go in either direction with this cut (push or pull), but pull is often much easier to control. Often this cut will reduce, or even eliminate tearout in those endgrain spots that are the bane of all turners.

Good luck with it.

Bill

[Glenn Hodges]

Kevin, I was having the same problem you mentioned, but after spending a day with Bill Grumbine when I was a newbee he showed me the method he uses. I am one of those that learns better by looking, and hands-on rather than just reading about a tecnique. Sometimes money spent to pay a master to help develop a good habit will reap rewards for a lifetime.