Bowl finish

[fredbelknap]

[img src="[/img]"]http://img24.imageshack.us/img24/3240/babybutt.jpg[img src="[/img]http://img252.imageshack.us/img252/7491/blackbowl.jpgimg188.imageshack.us/img188/192/img0120ef.jpg"]

My finish leaves a lot to be desired. The larger bowl is done with lacquer and the other ones are done with BLO and wax. The larger bowl feel kind rough with dust bibs. The two small bowls are smooth but they don't have the shine that most people like. Would buffing with rubbing compound on the lacquered bowl give it a smooth feel? Don't know what will make the oil finish a little brighter. Looking for suggestions.
Fred

edited: Thought I would post a closer look see of the smaller bowls. The black bowl is walnut and you can see a growth ring crack that I used CA on. It doesn't go through to the inside. The other is an oak and they both are as smooth as a baby's butt, I like that. I need to get a buffing system. Can I use a grinder (3500 rpm) with a buffing wheel or would it fly apart.
Dick I bet you did those steps on purpose.




Now my first picture has dissapeared. dadgumthunderation

[Joe Lyddon]

My experience has been that a BLO (oil) finish leaves a somewhat Satin finish... If you like Glossy, put a top coat of Arm-R-seal wipe-on or Poly-gloss... Shellac will also shine it up!

Have you tried sanding the nibs off the bowl with a very high grit?
... did you lightly sand the nibs between coats?

[TDHofstetter]

Fred, that lacquer can be smoothed out something' WICKED by sanding it out with very-high-grit sandpaper & then relacquering it, then touching it up with more very-high-grit paper if there are still some nibs, then relacquering it, so on & forth till they're gone. Or... just give it many many coats, rapid-fire, one on top of another, till it's really built up.. then sand it back. If you sand with 2000-grit paper, you'll get almost a wet-glass shine out of it that you can finish off with automotive swirl remover to make it look totally wet.

To bring the BLO up to a high shine, shellac it. It's best if you do that right on the lathe so you can rub out the shellac. After the shellac, topcoat it with lacquer if you expect the bowl to be exposed to water or alcohol (either will fog the shellac). The wax on those two will probably get in the way of the shellac, though... but that may respond very well to buffing. Which wax did you use on those?

[Doug B]

Fred, I have not done many bowls, so I am watching the answers right along with you.

I hope all the turners will chime in on this one.

[dicklaxt]

I always preferred a more natural buffed finish on bowls rather than a high gloss.

I usually just stuck with the Beall Buff System or a friction polish.

I guess that doesn't answer your question but Tim has the right idea I believe and thats many coats of lacquer with sanding in between.

I did that on the back door step and my practice wife slipped on it ,shot out the door and I haven't seen her since ,thats been 30 years ago.

dick

[Ruffnek]

Fred,

The lacquer will give a good shine if you sand it between coats with 400 grit and keep applying light coats. Since lacquer dries fast, it's probably not dust nibs but just overspray that is feeling rough to the touch. (assuming rattle can lacquer)

BLO and wax will give a soft shine but the BLO must be allowed to cure before waxing and buffing.

A very nice satin finish is Danish Oil or Minwax Antique Oil, allowed to dry and then Beall buffed. You can also buff film finishes like lacquer but you have to go lightly or you will generate too much heat and melt it.

3450 is too fast for the Beall 8" wheel buffs but would probably work with the 3" bowl buffs. I recommend you get one of those Don Pencil adapters to screw onto the headstock spindle and then the Beall buffs screw onto it. That way you can use the lathe to buff the pieces.

If you don't want to buff at all, then try Minwax Wipe-On Poly finish. Sand to at least 400 grit first and wipe on the finish with a piece of old t-shirt. Sand lightly between coats with 600 grit or 4-0 steel wool. After the 3rd coat, it will really begin to shine.

Edit In: Oh Yeah, Bill Grumbine and several other turners I know of have switched from Danish Oil to Bush Oil...I think because the Bush Oil is low odor...not sure, though.

[dicklaxt]

You can use the BBS on a grinder at 3500 RPM but its not recommended 1750 or even 1200 would be better,I always used the buffing wheels individually via an adaptor direct to the grinder .

The higher RPM will tend to grab the piece away from you and it creates more heat and that sometimes will dull the finish.I had it grab a 5" tall Mesquite Snifter that I had turned down to a 1/16th wall and it cracked like a dropped egg,I wanted to cry,,,,,,,,,,,

dick

[TDHofstetter]

Nov 16, 2009 7:01:35 GMT -6 dicklaxt said:

I had it grab a 5" tall Mesquite Snifter that I had turned down to a 1/16th wall and it cracked like a dropped egg,I wanted to cry,,,,,,,,,,,

dick

Oh, that would have HURT!

[Doug B]

I talked to Beall about using a 3450 motor and they said it would be fine for the bowl buffs and the 4" wheels but not with the 8" wheels. So I have 4" wheels on a cheap HF buffer motor www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=94393

The Beall adaptor fits just fine on the arbor shaft (only works on the right side shaft though). All in all it was a pretty inexpensive way to get the BBS set up.

[dicklaxt]

Doug please do some research on this speed requirement,,,,I have always heard that 1750 should be max,many of the old timers around will argue the use of speed greater than 1200.In my earlier post I can attest to the 3500 taking one of my more prised turnings for a ride and it did not return.I don't believe that would have happened with a 1700.

Some buffing compounds will gum up the wheel and surface of the turning because of heat.

What is the big push to go at a higher RPM?

dick

[Doug B]

I spoke to Mr. Beall himself about it. I wanted a 1750 motor, but could not find one at a reasonable price. He recommended the Baldor motors, but man those are pricey!

Their website says the following:
The Wood Buff is designed to be used with a 1/3 hp or more, 1725 motor. This should be sufficient for most buffing tasks; larger items or a more vigorous buffing style may call for 1/2 hp. The 3,000 r.p.m. of most grinder motors will be too fast for the 8" wheels sold with the Wood Buff but would work well for buffing with our smaller 4" Wheels or Bowl Buffs. When you face the shaft end of the motor, the wheel should rotate counter-clockwise in order for the Wood Buff to work properly.

www.bealltool.com/products/buffing/buffer.php

[TDHofstetter]

Ok - that's with a max 4" buff/wheel size. That gets ya... nom3600RPM ~ 60RPS ~ 753"/s (63'/s) rim speed.

[TDHofstetter]

Nov 16, 2009 15:25:26 GMT -6 TDHofstetter said:

Ok - that's with a max 4" buff/wheel size. That gets ya... nom3600RPM ~ 60RPS ~ 753"/s (63'/s) rim speed.

I do like the spelling on that page: "8" Wood Buggs with 3/4" Holes".

EDIT: Dang. What's UP with me punching "quote" when I meant "edit"

[Ruffnek]

I'm sure one of the math whizzes here could compare the outside speed of an 8" diameter wheel at 1725 rpm to the outside speed of a 4" diameter buff at 3450 rpm.

That would tell the story but I'm not brainy enough to calculate it.

[Doug B]

Yep, I got the 4" wheel kit and it seems to work just fine. Of course, it will still grab something out of your hands and fling in on the floor real hard if you are not careful. DAMHIKT!

[TDHofstetter]

Nov 16, 2009 15:28:43 GMT -6 Ruffnek said:

I'm sure one of the math whizzes here could compare the outside speed of an 8" diameter wheel at 1725 rpm to the outside speed of a 4" diameter buff at 3450 rpm.

That would tell the story but I'm not brainy enough to calculate it.

8"@nom1800rpm ~ 30RPS ~ 753"/s (63'/s) rim speed. Double diameter, half speed, same rim speed.

Figurin' it's not so tough, once you know a couple tidbits. The circumference of a disk = its diameter times pi (3.1415...). Not to be cofused with its AREA, which is its radius squared times pi.

So - 1800RPMinute divided by 60 to get RPSecond is 30. Multiply by its circumference in inches (8*3.1415 ~ 25) to get ~750 inches of rim per second. Divide by 12 to get ~63 feet of rim per second.