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Scott Hackler
04-14-2009, 1:46 AM
Well sort of newbie. I am pretty adapt at woodworking and costrustion so I know my way around the hammer, but I was wondering about some bowl sanding tips you pros might share.

The reason I ask is that I worked on a dried bowl with a micro scraper, then with 60 grit, then 150 emery cloth.. to 400 grit emery cloth and finally 600 grit of the same. The bowl is smooth as heck and looked pretty nice but after a little oil finish waws applied I could still see circular rings. I spent over an hour and a half and this was what I ended up with. Is there a better, faster way? I am going to order a heavy curved scraper or two to add to my collection.. thought this might help with tool marks.

BTW this bowl is out of an unknown white wood that I "borrowed" from a friends wood pile. It turned really well and I think it may be hackberry.

Thanks

Dewey Torres
04-14-2009, 2:03 AM
Scott,
You are skipping too many grits:

60 (if you must...most start with 80 or higher)
80
120/150
220
320
4-600 (or both)

If you stay close to the time and a half rule you should be ok:
example 60 * 1.5 = 90 next grit should no higher than 90.

Sandpaper is only good to remove the previous grit's scratches, therefore if you skip a grit the finer sand paper can't remove the scratch from the previous.

Your scratches are probably due to the jump from 60 to 150 but you also skipped a grit when you went from 150 to 400.

Jarrod McGehee
04-14-2009, 4:21 AM
Dewy, he did make a big jump from 60 to 150 and that's probably where the scratches came from but i think he then went in order to 400. but thanks for you tips. I'll try that 1.5 next time and see how everything turns out.

Steve Schlumpf
04-14-2009, 10:42 AM
Scott - I have to agree with Dewey - make sure you go through all the grits in sequence. I understand you are just starting out but highly recommend working on your tool skills so you do not have to start out sanding with 60 or 80 grit. Also, when sanding - make sure you are continuously moving the sand paper. Just a second's hesitation will cut a scratch into the wood. Also, if possible, repeat the final grit with the lathe running in reverse. This will remove all those small wood fibers that were missed and will result in an extremely smooth surface.

Burt Alcantara
04-14-2009, 12:02 PM
Scott,
The type of abrasive you use is very important. In the past I used Norton and Klingspor. They gave OK results but I found my finishes left me not all that satisfied. Many of the members on this forum recommend Vinces WoodnWonders. After running out of my usual stock I ordered a complete set from Vinces for 2" discs.

The results were amazing. The difference in the way Vince's paper cuts leaves all others in the dust...pun intended. When ordering that much paper you take a big hit to the plastic but the results you will achieve will take away all hesitation about re-ordering.

BTW, I use a power drill with a 2" pad. Not all drills are the same. Vince also sells a right angle drill. I suggest closing your eyes, gritting your teeth and buy a whole mess of sanding supplies. It only hurts the first time but the results you will achieve will make you one very happy turner.

Burt

Don Carter
04-14-2009, 1:13 PM
I agree with Burt. I was having problems with sanding finish until I go the Vince's sandpaper. I use an angled drill with a home made 2" pad. I was amazed at the difference Vince's blue sandpaper made.

Paul Atkins
04-14-2009, 1:22 PM
Practice making cuts that don't require sanding. Ideal, but really not obtainable in the real world, but I usually start with 220 which makes visible scratches minimal.

Reed Gray
04-14-2009, 2:07 PM
I am curious as to what the 'micro scraper' you used is. Some big heavy bowl scrapers are one of my main tools that I use on bowls, both for heavy stock removal, and finish cuts. If you are doing touch up work, you want a freshly sharpened scraper, with a nice burr, and you have the scraper up on its edge at about a 45 degree angle. The cuts will be very light, to the point where you will have to make a couple of passes to remove tool marks, and won't be able to do it in one pass. The roughing cuts are done with the scraper flat on your tool rest. This is not a finish cut as it 'pulls' on the wood fiber more than a shear (angled) cut and will leave you with tear out which is more difficult to remove than tool marks. This is easy to do on the outside of the bowl, but different on the inside. As you remove waste from the inside of the bowl, the rim gets flexable and will move as you put the tool to the wood. You have to hollow the inside of a bowl, especially as they get bigger, in stages. Take it down an inch or 2, then do your clean up cuts. Then take it down some more, etc till you are all the way down to the bottom.
robo hippy

Reed Gray
04-14-2009, 2:10 PM
I am curious as to what the 'micro scraper' you used is. Some big heavy bowl scrapers are one of my main tools that I use on bowls, both for heavy stock removal, and finish cuts. If you are doing touch up work, you want a freshly sharpened scraper, with a nice burr, and you have the scraper up on its edge at about a 45 degree angle. The cuts will be very light, to the point where you will have to make a couple of passes to remove tool marks, and won't be able to do it in one pass. The roughing cuts are done with the scraper flat on your tool rest. This is not a finish cut as it 'pulls' on the wood fiber more than a shear (angled) cut and will leave you with tear out which is more difficult to remove than tool marks. This is easy to do on the outside of the bowl, but different on the inside. As you remove waste from the inside of the bowl, the rim gets flexable and will move as you put the tool to the wood. You have to hollow the inside of a bowl, especially as they get bigger, in stages. Take it down an inch or 2, then do your clean up cuts. Then take it down some more, etc till you are all the way down to the bottom. I do my finish/touch up cuts on the inside of a bowl with a scraper, and pull it up towards the rim. This is backwards from the standard gouge cut, but it works. Note: the rim is very flexable, and can start to chatter. If you hear a howling noise, stop, and wait to clean up with the 80 grit gouge when you start to sand. The vibration can make your bowl explode.
robo hippy

Reed Gray
04-14-2009, 2:11 PM
I am curious as to what the 'micro scraper' you used is. Some big heavy bowl scrapers are one of my main tools that I use on bowls, both for heavy stock removal, and finish cuts. If you are doing touch up work, you want a freshly sharpened scraper, with a nice burr, and you have the scraper up on its edge at about a 45 degree angle. The cuts will be very light, to the point where you will have to make a couple of passes to remove tool marks, and won't be able to do it in one pass. The roughing cuts are done with the scraper flat on your tool rest. This is not a finish cut as it 'pulls' on the wood fiber more than a shear (angled) cut and will leave you with tear out which is more difficult to remove than tool marks. This is easy to do on the outside of the bowl, but different on the inside. As you remove waste from the inside of the bowl, the rim gets flexable and will move as you put the tool to the wood. You have to hollow the inside of a bowl, especially as they get bigger, in stages. Take it down an inch or 2, then do your clean up cuts. Then take it down some more, etc till you are all the way down to the bottom. I do my finish/touch up cuts on the inside of a bowl with a scraper, and pull it up towards the rim. This is backwards from the standard gouge cut, but it works. Note: the rim is very flexable, and can start to chatter. If you hear a howling noise, stop, and wait to clean up with the 80 grit gouge when you start to sand. The vibration can cause a catch, and make your bowl explode. We have all been there, and done that, and for most of us, more than once.
robo hippy

Mike Svoma
04-14-2009, 2:15 PM
Scott,

You may want to blow the piece off with your air compressor between grits to remove any grit that was deposited on your piece from the last grit. This "left over grit" can leave scatches also.

Tim Cleveland
04-14-2009, 4:56 PM
Mike Mahoney's philosophy is that you can always get a cleaner surface off of a gouge as opposed to a scraper. He does shear scrape with a gouge on the exterior of his bowls, but never scrapes (with a gouge or otherwise) on the interior. After watching some of his DVD's, taking a class from him, and a few conversations over the phone, I was able to eliminate 70% of my sanding time. I would strongly recomend that you get his bowl making DVD just to check out his methods before buying any scrapers. Also, using any oil as a finish will always accent any imperfections. I hope that this is able to help.

Tim

Maylon Harvey
04-14-2009, 10:58 PM
BTW this bowl is out of an unknown white wood that I "borrowed" from a friends wood pile. It turned really well and I think it may be hackberry.

Thanks
Scott,
Since you "borrowed" it does that mean you're going to return it to your friends wood pile.:D
Sorry, I couldn't resist.

Thomas Canfield
04-14-2009, 11:03 PM
Scott,

I have found it important to go through all the grits following the rule of 1.5 times previous grit, or 80, 120, 180, 220, 320, 400, etc. I was using 2" discs on right angle drill a lot until I got some Norton 3X sandpaper. Cutting the sheets into 6 pieces and then using them trifold, I have almost eliminated the power sanding and sped up the sanding process. It is important to have clean sandpaper with grit. There are T-shirts out there saying that "sed 80 grit is not 120 grit" or something similar. The grit is there to cut and good sandpaper really does pay in the long run. I am also finding that with practice, I can start often with the 120 or even 180 depending on the final cut.

Another tip I have heard, "Don't sharpen for the final cut, but sharpen for the final 3 cuts so that you can practice the final cut before making the final minimal cut". That has also helped my final cut.

Bernie Weishapl
04-14-2009, 11:12 PM
One thing I will tell you that emery cloth is not good for sanding wood. Especially the fine grits. Maybe metal but not wood. I agree with Tim after working with Mike Mahoney I have also eliminated a lot of sanding time. I usually finish the bowl with a conventional grind bowl gouge. As the others have said follow your grits and don't skip.

Scott Hackler
04-15-2009, 12:40 AM
No he isnt getting back the wood, but instead I think that the other two logs of this variety are gonna come up missing as well. This wood is very easy to work with and very light in color. I will have to ask someone who knows what the species is and then let you all know.

As far as the "scraper" I have been using. The description from the site I bought my 6 peice Sorby set from list it as "1/2" Shear Scraper with 2 tips" It is a square solid rod with a round cutting surface bolted to the tip and the whole tip is arranged in a 45 degree angle when the tool is on the rest.. I have started getting the hang of using it but I will be ordering a few new tools probally this week. I think I need a curved heavy scraper and some substantial bowl gouges.

As far as the sanding, I think that the use of a good gouge or a scraper might help eliminate the bulk of what needs sanded out and I will be considering an electric option for the sanding needs.

I have a half dozen bowls wrapped up in paper sacks, packed in shavings, siting on the garage floor! I turned a "spit-toon" style 8" bowl tonight out of elm. I sure hope this "piss elm" works out ok after drying because it looks fantastic while green. Sure smells bad though! :) Anyone else turn much elm?

alex carey
04-15-2009, 1:06 AM
better yet post a picture of the wood and we'll try and tell you what it is. we love pictures

Scott Hackler
04-15-2009, 1:31 AM
I will post a picture of a turned cup and maybe the other two logs from his pile! :)