When have you sanded enough?

Gord Rock

Member
Messages
619
Location
Red Deer, Alberta, Canada
This is a small bowl I made and I'm obviously either not sanding properly or long enough. I sanded from 80 grit through to 600 grit with every grit in between. Then I used the micro-abrasives that Lee Valley sells for sharpening.

http://www.leevalley.com/wood/page.aspx?c=1&p=33004&cat=1,43072

When I was finished the wood was smoother than glass. It looks and feels incredible but when I look very closely I can see some small scratches are still there. They may not show up very well in the photo but they are there. My wife tells me I'm too fussy but this is really bugging me.

How can I tell when I've sanded enough to go to the next grit. In my other woodworking I've always used power sanders of one type or another and never had this problem. Any advice or suggestions?

Also, the rim of the bowl looks like it's damaged but actually it picked some black marks from the rubber I used to cushion it in the donut chuck. I don't have a buffing wheel yet to try to buff that out. I hope to find one soon.

Thanks,
.....Gord
 

Attachments

  • small bowl 30-4-07 2.jpg
    small bowl 30-4-07 2.jpg
    65.6 KB · Views: 46
the other thing is that even at 1000..........4000 there are minute scratches. On pieces where:
1. I'm NOT going to stain..............which is ALL my pieces.
2. and I want a Gallery finish.


I am now Micro meshing to 4000 and then polishing to 10000, buffing with the Beal system, and adding a final coat of Carnuba wax, buffed out.

Just my way of doin' it - not necessarily good or not. take a look at my work here and judge for yourself. Sorry, not all pictures are that great.

Bruce
 
Last edited:
I don't make spinny-things but I was given a rule of thumb for sanding. This of course doesn't apply to veneers but then again, neither does turning as a rule.

A wise man once said; "I sand until I think I'm done, then I sand that much more again. I do this for each grit"

Another extreme option would be to approach it like sharpening tools; inspect with a magnifier until you see consistent striations then proceed to the next grit. You can wipe with mineral spirits to make any inconsistencies stand out. Cross lighting helps too.

Bernie brings up a good point; I have more than once, scratched a good surface due to not brushing or vacuuming between grits. A little chunk of 220 grit gets left behind, stirred into the mix while you're at 400 and your . . . sad.
 
Last edited:
Thanks for the replies.:wave:
I should have mentioned that I do remove the particles after each grit first I run a soft brush across the entire piece and then I blow it off with compressed air. :eek: If that isn't good enough to remove everything I don't know what else I could try.

Maybe I should stop sanding and leave at the wonderful job I do with the chisels.:rofl: :rofl: Does anyone ever really get that good? Maybe so but I don't imagine I'll be one of them.

.....Gord
 
Gord, it sounds like you might have switched to a finer grit a bit too early at one of the sanding stages. Plus. maple can be the devil to get scratches out of. They seem to keep sneaking back. That's happened to me. I'll be going through from 80 or 120 grit up, checking closely, work my way to about 400, then :doh: I'll see a scratch. (And that's even with wiping off the piece between grits.) I've finally learned that when I do see a scratch, to go back down a grit or two and work the scratches out. I also sand by hand or with a little 2" random orbital sander, especially if I can see concentric "ring" scratches from sanding the piece while it's turning.

I've gotten real picky about my sanding, and since my tool skills are still on the new side (read: rough), I spend more time sanding than a lot of good turners, but I sand until I get it right. Otherwise, it'll bug me to death every time I look at the piece. Still, I have no pride, and I consider 80 grit to be a turning tool when necessary. :D
 
Gord, it sounds like you might have switched to a finer grit a bit too early at one of the sanding stages.

Yes, that may be the case. I think I spend quite enough time on each grit but I also must admit that I'm impatient - about everything :doh: - and may not be allowing enough time on each grit. I have gone back and started over completely to get rid of scratches but they still seem to be there when I'm finished. Guess I'll just keep working on my technique until I get it right.:(

Also, for some reason I have been unable to buy any sandpaper recently in either 240 or 280 grit. I still have some here but will run out soon. Has anyone else noticed a shortage of 240 & 280 grit sandpaper?

.....Gord
 
I can relate in the impatience thing. Me too. As far as grits go, around here I'm only finding 220, so that's are the one I use. I go with 80, 120, 220, 320, 400, and 600.

There are about as many different sanding schedules as there are bowl drying techniques, and nearly all of them work well. (But of course every person you ask will say their procedure is the best. Just ask 'em.) :rofl:

By the way, I like the little bowl in the pic. It sure looks smooooooooth. I sure can't see any scratches in it, but obviously they're there, or you wouldn't be asking about them. :)
 
Gord I got to watch a turner Mike Mahoney one time. He said and it has stuck with me since, start at 80 grit and go to 600 grit on bowls. On boxes I generally stop at 400 grit. He said where the new turners get in trouble is they think it looks good and they will skip one or two grits. He said they may jump from 150 grit to 220 or 320 grit. He also said another mistake made is to leaving the sanding dust on from the previous grit. He said to use a air hose to blow off the dust from the previous grit before going on to the other. He said if you don't there will be grit left behind from the previous sandpaper. When I have went thru all the grits in progression I will wipe with mineral spirits. Look it over real good to see where I have problems. If you have scratches they will definitely show up. If it looks good I finish with some type of oil finish and buff with the beall buff system. Like Bruce don't know if it is right or wrong but it does the job for me.
 
Gord, it may be just me, but I find 80 grit is too aggressive for turnings and it tends to leave deep swirly scratches. On occassion, however, I'll turn a piece of spalted Maple that wants to tear out in a few places in spite of my best effrts and I have to start with the courser grit. On these occassions, I find it takes about as long to get the scratches out with 120 or 150 as it does to through the rest of the grits combined. More often than not, I can start sanding with 150, or even 220, and I've been a lot happier with the end result. FWIW
 
In my other woodworking I've always used power sanders of one type or another and never had this problem. Any advice or suggestions?

I often have to remind myself to "keep 'er moving" when I sand. One of the things about power sanders (like orbital units) is that they keep presenting a different arrangement of abrasive particles to any given spot on the workpiece. That helps to prevent long scratches.

With hand sanding, you have to do the "moving" yourself. If you find that you're pulling a slow spiral in a single direction with your sandpaper, try using more of an "orbital" action, or at least a back-and-forth movement roughly parallel to the lathe bed.
 
What about something like the Monster Bowl sanders? Are they something that might help keep the scratches to a minimum?
 
I agree with Billy...I try to avoid using the bigger grits, since it takes so much time to remove the scratches they leave. On punky stuff that's prone to tearout though, sometimes that's the only way I've been able to smooth things up.
What about something like the Monster Bowl sanders? Are they something that might help keep the scratches to a minimum?
The spinning bowl sander on a stick works pretty well, especially on bowls, but they don't get into all the nooks and crannies of a hollow form (I've got the Monster version). I've also got the Grex pneumatic 2" ROS, so I tend to use that on bowls, and the Monster sander in places I can't reach with the Grex (like hollow forms).
 
Top