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My arm is tired (I need finishing advice)
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Author:  John How [ Thu Mar 13, 2008 5:32 pm ]
Post subject:  My arm is tired (I need finishing advice)
Right now I have 6 guitars in the process of being finished and am doing the before buffing sanding on 4 of them. I do this wet and by hand and it is very tiring and the part of the job that I least enjoy. I am hoping that I have been left in the dark ages and that someone will clue me to a faster and easier way to level and ready the finish for buffing. Perhaps you know of something I am missing. Maybe one of our finish pros would offer a hint if it's not too much of a trade secret to pass along.
By the way, I use Nitro lacquer for my finishing

Many thanks in advance!!! [uncle]
Author:  LuthierSupplier [ Thu Mar 13, 2008 6:22 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
John,
I wish I could help you here, but I'm just a newbie. However, you might want to give Charlie Hoffman a call. I saw this on his website http://hoffmanguitars.com/finish1-6.jpg

You can go to this page on his website where he talks about this air powered Dynabrade sander: http://hoffmanguitars.com/FINISHBODY1.htm

Good luck, and go ice that arm :lol:
Author:  Blanchard [ Thu Mar 13, 2008 6:39 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
I do all my wet sanding by hand as well. It is slow and tedious and because of that try not to do more than one guitar at a time. It is one of the reasons I don't build in batches. I just don't want to end up with 4 or 5 guitars that all need wet sanding at the same time.

I have tried various methods of power sanding and I haven't yet found a method that gives me the results I want. I always seem to go back to hand sanding. I actually rely quite a bit on the sound that the sandpaper makes to tell me when I have sanded enough in a certain area. I don't get that feedback when power sanding and I find I'm more likely to sand through because of it.

Mark
Author:  James Orr [ Thu Mar 13, 2008 6:44 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
Hey John

I really liked the results I got with my Festool sander, 400 grit to 1000 and 2000 platin 2. The platin series are foam backed pads made especially for the pre-buff sanding for high gloss finishes. I will say that I think the results will be better if I level with 400 and use 500 platin to 1000 to 2000. The recommendation is 500 to 1000 to 2000.

What I REALLY want to know is how you guys deal with small areas like the waists and cutaways of acoustics and the cutaways on strats, teles, etc. My sander does get there.
Author:  Sheldon Dingwall [ Thu Mar 13, 2008 7:12 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
LuthierSupplier wrote:
John,
I wish I could help you here, but I'm just a newbie. However, you might want to give Charlie Hoffman a call. I saw this on his website http://hoffmanguitars.com/finish1-6.jpg

You can go to this page on his website where he talks about this air powered Dynabrade sander: http://hoffmanguitars.com/FINISHBODY1.htm

Good luck, and go ice that arm :lol:


The smaller orbital sander he's wet sanding with is a Nitto Kokki (sp).

We gave up on wet sanding. We sand everything dry with Dynabrade Random Orbits. We're sanding polyester, but I'm sure you can dry sand lacquer.
Author:  Robbie O'Brien [ Fri Mar 14, 2008 8:46 am ]
Post subject:  Re: My arm is tired (I need finishing advice)
You can dry sand most of the finish and then complete the job with a quick wet sand if you like. Norton makes a dry sandpaper that works well for this. I sometimes start as low as 1000 or even 800.
Areas like the waist and other detailed area need to be done by hand.
Author:  Michael Dale Payne [ Fri Mar 14, 2008 8:57 am ]
Post subject:  Re: My arm is tired (I need finishing advice)
I can't believe any of you would wet sand with an electric variable speed Ross. You might get away with it 50 times but that 51st is a killer wow7-eyes
Author:  Alain Moisan [ Fri Mar 14, 2008 9:19 am ]
Post subject:  Re: My arm is tired (I need finishing advice)
Good point Micheal. I was thinkning the same thing.

I'm looking for a battery powered sander for that same reason.
Author:  Bob Long [ Fri Mar 14, 2008 11:52 am ]
Post subject:  Re: My arm is tired (I need finishing advice)
Larrivee does something he calls "Bull Buffing". to level out the finish prior to wet sanding. It's mentioned briefly on his website. I really don't what it is he's doing, but it might be worth giving him a call.

long
Author:  Chas Freeborn [ Fri Mar 14, 2008 12:48 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
With all the modern abrasives available I've all but given up on wet sanding. The Mirka Abranet seems to clear the sanding dust very well, but be sure to get their sander pad to go along with it. I've got one on a Dynabrade small orbit sander, which is my choice of RO sanders. I finish with the Mirka soft pad "abralon" starting with a 1000 and finishing with a 2000.
My other favorite sanding tool, which would be primo for wetsanding, if you insist, is the Nitto LS-10. It's a tiny straight line sander that you can velcro different shaped pads onto. I've got a set of pads specific to guitarmaking. Needless to say, pneumatic is the way to go when there's water present.
One small tip for wet sanding- put a dash of dishwashing detergent (liquid) into the water. It helps the paper not load.
-C
Author:  Erik Hauri [ Fri Mar 14, 2008 6:46 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
I use a RO sander with 600 wet to level on solidbody instruments where the clearcoat is on the thick side.

For acoustic instruments with a thinner finish, I level with 600 wet by hand.

For both, I'll then go to 1000-2000-4000-grit Abralon wet with the RO, except the sides get done by hand because the finish is thinner there. Then buff out.

I've not had good luck dry sanding, I've never been happy with the dust clearing (or lack of).

DEFINITELY soap in the water when wet-sanding, surfactant don'tcha know. [:Y:]
Author:  Don Williams [ Fri Mar 14, 2008 6:51 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
Sheldon Dingwall wrote:
The smaller orbital sander he's wet sanding with is a Nitto Kokki (sp).

We gave up on wet sanding. We sand everything dry with Dynabrade Random Orbits. We're sanding polyester, but I'm sure you can dry sand lacquer.


Hey Sheldon, who is "we"? Do you work with another builder? Or do you work with Charlie?!
Author:  Sheldon Dingwall [ Fri Mar 14, 2008 7:28 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
Don Williams wrote:
Sheldon Dingwall wrote:
The smaller orbital sander he's wet sanding with is a Nitto Kokki (sp).

We gave up on wet sanding. We sand everything dry with Dynabrade Random Orbits. We're sanding polyester, but I'm sure you can dry sand lacquer.


Hey Sheldon, who is "we"? Do you work with another builder? Or do you work with Charlie?!


Hi Don, I've got 6 guys plus myself and outside sales here. No Charlie though.

Wet-sanding has a lot of things going for it. What I didn't like was that if you use water and the water finds one tiny screw hole that didn't get filled properly the grain will swell and your finish is ruined. We wet-sanded for a while with mineral spirits, but it was just too unhealthy.

Most production shops I've toured dry-sand.
Author:  John How [ Fri Mar 14, 2008 11:41 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
Chas Freeborn wrote:
With all the modern abrasives available I've all but given up on wet sanding. The Mirka Abranet seems to clear the sanding dust very well, but be sure to get their sander pad to go along with it. I've got one on a Dynabrade small orbit sander, which is my choice of RO sanders. I finish with the Mirka soft pad "abralon" starting with a 1000 and finishing with a 2000.
My other favorite sanding tool, which would be primo for wetsanding, if you insist, is the Nitto LS-10. It's a tiny straight line sander that you can velcro different shaped pads onto. I've got a set of pads specific to guitarmaking. Needless to say, pneumatic is the way to go when there's water present.
One small tip for wet sanding- put a dash of dishwashing detergent (liquid) into the water. It helps the paper not load.
-C


Thanks for the tips guys. I dry sand with the RO at 320 between coats and then finally after spraying but before wet sanding with 800, 1000 and sometime 1500, then buff. It is all that wet sanding that I don't like.
I think I'll check into dry sanding with finer grits. Chas, where do you get your abralon? I assume you can get it in discs for a Ro type sander. It seems like I heard that once before but never did try it.
Author:  npalen [ Sat Mar 15, 2008 8:17 am ]
Post subject:  Re: My arm is tired (I need finishing advice)
I've tried dry sanding several times on nitro with some of the new technology out there including Abranet, gold paper etc.
Just don't care for the "feel" of it. Wet sanding is, for sure, messy but at least it doesn't generate dust.
Maybe I'm a glutton for punishment but I enjoy the final sanding prior to buffing. It's relaxing time and a TV set in the shop lets me watch the ball games, DIY and RFD.
To each his own?
Nelson Palen
Author:  Michael Dale Payne [ Sat Mar 15, 2008 10:57 am ]
Post subject:  Re: My arm is tired (I need finishing advice)
John How wrote:
Chas Freeborn wrote:
With all the modern abrasives available I've all but given up on wet sanding. The Mirka Abranet seems to clear the sanding dust very well, but be sure to get their sander pad to go along with it. I've got one on a Dynabrade small orbit sander, which is my choice of RO sanders. I finish with the Mirka soft pad "abralon" starting with a 1000 and finishing with a 2000.
My other favorite sanding tool, which would be primo for wetsanding, if you insist, is the Nitto LS-10. It's a tiny straight line sander that you can velcro different shaped pads onto. I've got a set of pads specific to guitarmaking. Needless to say, pneumatic is the way to go when there's water present.
One small tip for wet sanding- put a dash of dishwashing detergent (liquid) into the water. It helps the paper not load.
-C


Thanks for the tips guys. I dry sand with the RO at 320 between coats and then finally after spraying but before wet sanding with 800, 1000 and sometime 1500, then buff. It is all that wet sanding that I don't like.
I think I'll check into dry sanding with finer grits. Chas, where do you get your abralon? I assume you can get it in discs for a Ro type sander. It seems like I heard that once before but never did try it.



I know Micromesh sells hook and loop discs and ps discs. I asume Abralon does as well. You can get Micromesh at http://www.micro-surface.com
Author:  Chas Freeborn [ Sat Mar 15, 2008 1:06 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
Abralon is a Mirka product (as is Abranet) I get it at my local independent woodworking supply store, but I'd guess it's available from some of the larger outfits (Woodcrafters,etc.) too.
It's a hook 'n loop type of deal. The pads are 6", but I run them on my 5". One note- it's got a soft foam core, so it's not well suited for leveling. Do that with your RO, or with hand blocks.
Festool makes a similar product, which I'm sure is great, but at my store they only sell them in boxes of 100, which are $50 a pop. Multiply that by 3 or 4 grits....
You can rinse out the Abralon after using it and use it again.
I've made an assortment of guitar specific sanding blocks out of homosote. I'll take some pics and put together a post when I've got a chance. Timing is good, I'm sanding and buffing a couple of bodies today.
-C
Author:  Sheldon Dingwall [ Sat Mar 15, 2008 5:36 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
3M 260L products are what we use. We've tried just about everything else.
Author:  Brad T [ Sun Mar 16, 2008 8:10 am ]
Post subject:  Re: My arm is tired (I need finishing advice)
some pics of a flow coat. The peghead is 3 coats over 320 leveled vinyl sealer and 2 flow coats. The guitar is over 600 grit leveled lacquer. I tried to get the reflection of the light on the surfaces to accentuate the lacquer surface as much as possible. I think I can get it better with some more work.
Author:  Tim McKnight [ Sun Mar 16, 2008 8:40 am ]
Post subject:  Re: My arm is tired (I need finishing advice)
HI John,
The problems I ran into when dry sanding Nitro is that the finish is much softer and loads [gums] up the paper rather quickly. Another reason why I like the catalyzed urethanes so much is they don't load up the paper when sanding. It is akin to sanding Nitro sanding sealer where it powders up realy nicely.

My sanding schedule (for urethane) is:
Use a DeWalt 5" RO sander with the following grits [dry]:
Grizzly 400 gold if there are runs or heavy orange peel
Grizzly 600 gold
Mirka 1000 gold

Dynabrade 5" RO (wet) using a water and Murphy's Oil soap mixture with Mirka 2000 Abralon. The Abralon discs are about $3.50 EACH!!! but they last a good long time.

Next is buffing with 3 grades of Menzurna: medium, fine and very fine. Urethane is much harder to buff than Nitro that is why it takes 3 grits.

I tried Mirka Abranet but found it to leave much deeper scratches since the surface is not as flat as sandpaper. I purchase Mirka online through Homestead Finishing Products.

Grizzly abrasives do not hold up well wet sanding (water soluable glue) but I prefer their products for dry sanding. Mirka will wet sand a lot better because the glue that holds the abrasives on is not water soluable.
Author:  Brad T [ Sun Mar 16, 2008 11:13 am ]
Post subject:  Re: My arm is tired (I need finishing advice)
Tim,

Have you ever tried the 3M Fre-cut gold on nitro? I have found that it is the only paper I can dry sand nitro with and it not load, even as early as 12 hours after spraying. It doesn't last long before wearing out, but it doesn't load up, at least for me. I dry sand with 600 grit to level at coat #3 with it. I hand sand because I'm sure, with my luck, I would screw up something with my RO :D
Author:  Glen H [ Mon Mar 17, 2008 12:14 pm ]
Post subject:  Re: My arm is tired (I need finishing advice)
I second the 3-m fre-cut papers. Since I started using them, I tossed the wet sanding out. I can level an entire guitar with 800 grit Fre-cut using only about 2 sheets of paper. Stew Mac sells it.
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