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  #1  
Old 09-11-2021, 11:53 AM
Fathand Fathand is offline
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Default ? Sanding Waist area, Shellac

I have built a Martin 1918, 1-18 replica, sprayed with shellac. It is almost dry enough to sand level and buff.
Does anyone have any suggestions on sanding the sides in the waist area?

I find it hard to get in there. I am usually using styrofoam to back the wet sandpaper. Been using water but have been told there are better choices for shellac I have had decent results on small areas like a headstock but less luck on a large surface like a back.
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Old 09-26-2021, 02:45 PM
Quickstep192 Quickstep192 is offline
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I use naphtha for sanding lubricant on Shellac.
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Old 09-27-2021, 09:40 AM
Skarsaune Skarsaune is offline
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I've used sandpaper wrapped around a piece of PVC to sand in the waist area on guitars before finish - if you like styrofoam, get a round piece and have at it.

edit - I had another thought. Pool noodle as a backing pad, if you can find one in a small enough diameter.
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Old 09-27-2021, 04:52 PM
lar lar is offline
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You can also buy a foam pipe insulator (the kind that you put around hot water pipes, Home Depot has them and they are cheap), then cut a pvc pipe and slide it in inside the insulator.
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Old 09-27-2021, 06:29 PM
redir redir is offline
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You have to be extraordinarily careful in that area . Something soft to back or just folded paper and BARELY sand it. I don't wet sand shellac anymore but when I did I used walnut or olive oil.
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Old 09-27-2021, 06:40 PM
Rudy4 Rudy4 is online now
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Any time I'm sanding contoured areas I back with cork that comes in 1/4" thick 12" by 12" squares that is sold to make bulletin boards. It's normally sold 4 pieces to a pack and is a great thickness to use for caul pads and sandpaper padding.

Cut whatever size you want and attach sandpaper with double back carpet tape.

I typically cut my sanding pads 2-3/4" by 5-1/2" because that's the size I cut my 8-1/2" by 11" sheet paper to have a convenient size on hand.
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Old 09-28-2021, 06:11 AM
Fathand Fathand is offline
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Quote:
Originally Posted by Rudy4 View Post
Any time I'm sanding contoured areas I back with cork that comes in 1/4" thick 12" by 12" squares that is sold to make bulletin boards. It's normally sold 4 pieces to a pack and is a great thickness to use for caul pads and sandpaper padding.

Cut whatever size you want and attach sandpaper with double back carpet tape.

I typically cut my sanding pads 2-3/4" by 5-1/2" because that's the size I cut my 8-1/2" by 11" sheet paper to have a convenient size on hand.
So the 1/4" cork flexes to follow the inner curve and it doesn't crumble?
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Old 09-28-2021, 06:32 AM
Rudy4 Rudy4 is online now
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Quote:
Originally Posted by Fathand View Post
So the 1/4" cork flexes to follow the inner curve and it doesn't crumble?
The 1/4" thick sheet cork produced to use for bulletin boards is flexible and doesn't crumble or break apart unless it is bent beyond a sharp 90 degree angle.

I've been using it in my shop for years. I've never found anything better for padding clamping cauls, so it gets used for that and many other purposes.
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Old 09-28-2021, 07:08 AM
phavriluk phavriluk is offline
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Default A thought

I like the cork idea. I've been using large diameter wooden dowels, but plastic pipe and cork sounds like a variation I'll try. Larger diameter, the better'

Thanks!

And an inflatable rolling pin sander sure helps if used carefully. Bought that, used that too.
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  #10  
Old 09-28-2021, 01:41 PM
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Bruce Sexauer Bruce Sexauer is offline
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I no longer use conventional sandpaper at all on my sides, preferring Norton SoftTouch. I use 320/400 early, 800/1000 in the middle, and 1200/1500 pre-buffing. When I did use sheet goods, I back it with cut to size (2 x 3 inches is good) pieces of Flip-Flop, available in Stores every where quite cheap at summer’s end. That’s about now. They come in various densities, and the softer types are excellent for the waist.
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Old 09-28-2021, 04:51 PM
runamuck runamuck is offline
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There is good advice here and to add, don't use water as a lubricant with shellac. Shellac is not water proof and you can get blushing.
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Old 09-28-2021, 05:36 PM
Fathand Fathand is offline
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Quote:
Originally Posted by runamuck View Post
There is good advice here and to add, don't use water as a lubricant with shellac. Shellac is not water proof and you can get blushing.
Yes, since the original post, I borrowed some EVOO from the kitchen. It works great, no corning at all. I do have to remember to bring it back in time for sauteeing the bacon and onions for boeuf borguinon.
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Old 09-28-2021, 05:39 PM
Fathand Fathand is offline
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Quote:
Originally Posted by Rudy4 View Post
The 1/4" thick sheet cork produced to use for bulletin boards is flexible and doesn't crumble or break apart unless it is bent beyond a sharp 90 degree angle.

I've been using it in my shop for years. I've never found anything better for padding clamping cauls, so it gets used for that and many other purposes.
Thanks Rudy, I have been liking leather for pads on my cam clamps and for cauls sometimes. I have lots around from making banjo straps. I will see if I can find some 1/4" cork.
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Old 09-28-2021, 05:44 PM
Fathand Fathand is offline
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Quote:
Originally Posted by Bruce Sexauer View Post
I When I did use sheet goods, I back it with cut to size (2 x 3 inches is good) pieces of Flip-Flop, available in Stores every where quite cheap at summer’s end. That’s about now. They come in various densities, and the softer types are excellent for the waist.
Good tip on the flip flops, I still call them thongs though, much to my daughter's chagrin .
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  #15  
Old 09-28-2021, 07:35 PM
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Bruce Sexauer Bruce Sexauer is offline
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Quote:
Originally Posted by Fathand View Post
Good tip on the flip flops, I still call them thongs though, much to my daughter's chagrin .
Also: Zorries, and Go-Aheads.
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