# New to Bowl turning, need help



## davidrei (Jul 17, 2007)

While I'm still making pens, I thought it would be good to expand my horizons into bowl turning.  Not wanting to intrude too much on this forum, are there similar forums for bowl tuners?

My problem is (very) basic sanding technique. I can't seem to get the insides of the bowl smooth and without sanding lines.  This has been a problem on each of the half dozen or so bowls I've attempted,  Case in point is this one currently on the lathe.  It's Brazilian Cherry, about 6 inches in diameter and turned to about 1/8" thick.  I'm using the Sorby sanding thingy as shown.  Sanding the outside of the bowl goes very well, with out any problems.  After shear scraping, the inside looks good, with the exception of some stubborn end grain, which I'm pretty sure is due to vibration and I think I know how to fix that.  But as soon as I start sanding I have 'permanent' sanding lines that just don't seem to go away.  Any pointers to FAQ's, tip files other sites, etc. would be most appreciated.


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## vick (Jul 17, 2007)

For general turning I hang out at sawmill creek.  Good bunch and some familiar faces from here.
I will answer your question with a couple questions
What grit progression are you using? (example 80,120,150, 220)
Are you wipeing down the bowl between grits?  If so are you using something like DNA to wipe it down.
What wood is this bowl, or is this happening on all of your bowls?

also the line by the rim looks like tear out not sanding scratches, you have to do a lot of sanding to get rid of that.


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## davidrei (Jul 17, 2007)

This has happened on a number of different types of wood, maple, eucalyptus, east indian rosewood and red morrel burl in addition to the brazilian cherry shown.  After shear scraping, I start with 180 grit, which seems to me about right given the quality of the surface after scraping.  From there I go to 220, 320, and 400.  But the problem starts right at the beginning with the first grit, whatever it is.  I just can't get rid of the sanding lines.  

And yes that is tear-out near the rim. Like I said, I believe that with the fairly thin wood, I'm not sufficiently controlling vibration to let the scraper get it, but I think I know how to fix that.

Thanks for taking the time to listen to my woes [)]


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## Rojo22 (Jul 17, 2007)

I would ask a few questions before answering as well:

1.  Speed of the lathe while sanding?

2.  Grit progression?

3.  Can those scratches be from the tool edge or paper edges?


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## davidrei (Jul 17, 2007)

Turning at 1500 rpm, sanding at 600 rpm.  I thought it might have been an edge of the sander or a crease on the paper or something like that.  Tried different angles on the sander, tried hand sanding, kept a close eye out for edges, but I don't think that's the problem.  I saw a new foam rubber 'mesh' thing a Lowes last weekend, I might give that a try, since it has no edges and is much more flexible than the normal foam sanding sponges.


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## vick (Jul 17, 2007)

I dont meen to be insulting but very few turners can get away with starting sanding bowls at 180.  Some may think they can but they are going to be their a while or have a bad finish.  Many professional turners start at 80 grit and if you have tear out you probably should not even consider anything higher.
You did not answer the question about wipeing down betwean grits, but if you are not consider putting a little DNA on a paper towel and get rid of all of the dust and spare grits that might have came off of your paper.  If you dont remnents of the previous grit can remain and mess with your surface when you try to go to a higher grit.
600 RPM seems a reasonable speed.
Not all sandpaper is created equal make sure you are using a decent quality sand paper if they do not have fairly uniform particle size you can run into problems.

I know many people like the inertia sanders but I am not one of them.  Yes I do own one and have used it several times.  For the inside I have one of the velcro heads that I put into a cordless drill and it seems to work better for me.

If you are planning on using an oil based finish wet sanding at certain points can help tremendously.  I dont wet sand with the disk since they will get clogged much quicker and they are expnsive. I will use regular paper to sand with either a BLO mineral spirits mix, or Watco right out of the can.  I will wet sand with 80 grit paper in my hand to make quick work of the tool marks and then wipe it down with DNA and change to the disks, yes I do the 80 grit again with the velcro head.  Anything over 220 I use regular paper so I sometimes wet sand again then (I pretty much only use wipe on wipe off oil fisihes so I have not compatability issues).  At the higher grit it is more to fill the woods pores.

Be carefull of not putting to much preasure when sanding a light touch seems to work better for me.
Other then that I will have to say you need to sand until all the marks fron the previous grit is gone.  I can still easily see sanding lines until I get past 220 past 400 hundred I can't realy see them.  Make sure you have a good light source comeing in at a low angle and really inspect the piece after you wipe down.  If you are missing spots make sure you go back and get them before going to the next grit.

I used to have a lot of problems with sanding lines but sanding like turning is something you seem to get the hang of with a little practice.

I am not an expert on this by any means just letting you know how I do it.  If you have an experienced turner locally try to get him to come over and watch you see if he or she can pick something you are doing that is causeing the problem.


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## vick (Jul 17, 2007)

one more thing read this
http://www.woodcentral.com/russ/finish2.shtml
Russ knows a lot more then me and probably explains it better as well.


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## davidrei (Jul 17, 2007)

You're not being insulting at all Mike, since I can not yet claim to be a real bowl turner [].  Thanks for the advice and the link, they both  give me much to consider.  BTW, I do wipe with DNA (or some such thing)between grits, a lesson I learned the hard way with pens.


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## Ron in Drums PA (Jul 17, 2007)

Mike gave you some good pointers, listen to him.

One thing I would add is not to move to a higher grit until you are completely finished with the lower grit.

The problem shown in this picture is (it would at about 4 o'clock near the rim) 



you are getting tear out. It could be tool control or just ornery wood.

Lets assume it's ornery wood, try wet sanding with your 100 grit gouge. (If it was worse I would say use your 60 grit gouge). Most people use what ever finish they plan on using to wet sand. For me, I use some home brew danish oil.

It might be that the bowl is flexing while you are turning. This happens with thin bowls. You may need a steady, although this problem is usally found with deeper and/or larger bowls





The sanding rings may be because you are holding the paper in one place to long, although that doesn't usually happen with the rotary sander you are using.

Stopping the lathe between each grit and sand with the grain will help remove those sanding rings.

Lastly, try sanding by hand, just to see what happens.


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## hilltopper46 (Jul 17, 2007)

THANK YOU for this post and the responses.  I now have some things to try in an area that has frustrated me no end.


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## low_48 (Jul 17, 2007)

Thought I would add another tip for you with those deep scratches. After doing some to the course sanding, I take a slightly damp rag and wipe down the bowl with the lathe shut off. It seems to swell the rough fibers of the wood and scratch more than the tight grain. I let it dry and then finish sanding. I've never used that type of sander, always use a pad on a drill. My favorite new sandpaper is Abranet. Just some wonderful stuff.


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## exoticwo (Jul 18, 2007)

What you have there Dave are Tool Marks.
 Your cutting edge is skipping across the wood in that area (transition area).
The only thing to do is start your sanding process over and get the whole area down to the same level as the lines, which are deeper and show up real good next to the shiny sanded wood around it.
  The transition area from side wall to bottom is almost always the hardest area to cut smooth even with support, slow speed and Sharp tools. Perhaps on the next one, and you know there will be a next one, try a little putting a lite coat of finish on then performing your Finsihing cuts. This will help you see areas that need attention and smooth your cut. Very lite pressure and swing tool completly from lip to center or vice versa.

 Plenty of very good advice on how to finish in this thread !! 
Best of luck,


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## exoticwo (Jul 18, 2007)

Ron, interesting Steady Rest you show in the above pcture. Is there another on top or either side to stop movement in that direction?? 
Not a hijack!! just a question.[]


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## Ron in Drums PA (Jul 18, 2007)

Not On this one Al, but it can be done

Check out Russ's bowl steady http://www.woodturnerruss.com/BowlSteady.html


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## exoticwo (Jul 18, 2007)

Thanks Ron, I already use Russ's stlye, just haven't seen ours before.


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## dbriski (Jul 18, 2007)

One tool I use on my larger bowls / platters is my Random Orbit Sander.  It makes quick work of the sanding tasks, especially in the lower grits.


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## vick (Jul 18, 2007)

On the subject of bowl finishing. 
 A little off topic for this post but I thought I would share with you because I wish someone would have beat this into my head years ago.  Once you get your sanding problems worked out their is a secret to getting a killer finish on your bowls.  It is a secret that everyone knows about Buffing.  I was not a firm believer in buffing when I was doing mostly pens because after micro meshing I saw little difference (just my opinion), so I never tried it on my bowls when I first started doing them.  However on bowls it makes a world of difference.  
If you dont believe me visit a turning club and pick out the best finished bowls in the instant gallery and ask the makers if they buff.  I would guess over 80% will say yes.


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