Mother of Pearl dust embedded in fret board

mness4

Junior Member
Joined
Nov 17, 2020
Messages
26
Reaction score
3
I'm finishing the neck shaping on my first guitar...an SG. I've sanded through 220 grit with a 12" radius caul. I cannot seem to avoid having the mother of pearl dust embedding itself in the fret board. I've attached an image. I doubt this will go away as I sand to higher grits. Does it become less visible once the finish is applied. I've vacuumed the dust and followed up with a tack cloth between each grit. Not sure what else I could do. Any suggestions?
 

Attachments

fatdaddypreacher

V.I.P. Member
Joined
Feb 5, 2011
Messages
7,065
Reaction score
5,263
get a stiff toothbrush or a similar nylon bristle brush....maybe even brass, but definately not steel, and lightly go with the grain. you may even have one of those cheap throw away 'chip brushes' ...paint brushes around the shop that you can cut the bristles short and coax them clean with it. should lift out with no problem. as far as finish....the only times im familiar with a finish being put on a fretboard is when maple is used. continue to sand board with finer grits thru 2500 or so, and i think you will be pleased with it. the only other thing it should need is oil, if you are of the notion.
 

mness4

Junior Member
Joined
Nov 17, 2020
Messages
26
Reaction score
3
Thanks for the quick reply. I did mean oil as a finish. I have a toothbrush I can try cleaning as you suggest.
On a related note, next I'm going to spray paint the holly head stock veneer after inlaying a MoP logo. I've heard of an old school approach where the inlay is set a little proud of the surface, then the head stock and inlay are spray painted (black), and then wet sanded to reveal the MoP. Did I hear this right or should I simply mask off the inlay and spray?

Thanks
Mike
 

fatdaddypreacher

V.I.P. Member
Joined
Feb 5, 2011
Messages
7,065
Reaction score
5,263
typically i set mine in black epoxy. i mix a little expoxy and color it with a little black ink. after it is all sanded flat i simply mask off. if its rather intricate, i have had good success with painting the inlay with mastic generally found in the art departments in the water color section. it's a liquid much like rubber cement. after it dries and the painting is done, you can roll it off with your fingers. if it's a simpler design, i use masking tape. hope that helps
 

mness4

Junior Member
Joined
Nov 17, 2020
Messages
26
Reaction score
3
Great. Thanks. I'll try your approach. My graphic is not complicated. I had been concerned about wet sanding unevenly. This sounds more straightforward. BTW, the toothbrush did not work. I'll try something a little stiffer, but I'm afraid maybe I sanded too hard? I cannot scratch out any of the little pieces.
 

fatdaddypreacher

V.I.P. Member
Joined
Feb 5, 2011
Messages
7,065
Reaction score
5,263
Great. Thanks. I'll try your approach. My graphic is not complicated. I had been concerned about wet sanding unevenly. This sounds more straightforward. BTW, the toothbrush did not work. I'll try something a little stiffer, but I'm afraid maybe I sanded too hard? I cannot scratch out any of the little pieces.
dont ever remember having this issue. mine always cleaned up quite readily. good luck
 

endial

Senior Member
Joined
Oct 22, 2014
Messages
3,428
Reaction score
3,666
Using masking tape to pick up embedded particles works well.

Using duct tape (use a NEW roll) works even better.
^This.

Plus, the bristles of a toothbrush are too large to get into those fine pores. You should try something stiff but natural. Natural, because natural bristles break off to a fine taper and come to a point. Plastic (toothbrushes) man-made bristles are thick and they round off or break off square. Tape will work as well as anything though, and you might have to go through a couple different types, like blue painter's tape, plain manila masking tape, and then go with duct tape for the kill. Mind you, duct tape might take some fine grain with it. No Scotch tape, or boxing tape. Those can leave adhesive behind on your product.
 

pshupe

Senior Member
Joined
Jan 19, 2012
Messages
5,551
Reaction score
5,824
I've done quite a bit of pearl and never had this issue. I use a compressor to blow the rosewood dust off the board and my sandpaper very regularly. I use a radius sanding beam from 80 - 320 grit and even hand sand up to 800 or so, depending on the board. The compressor blows out the dust really well. Have you tried that?

Cheers Peter.
 

pshupe

Senior Member
Joined
Jan 19, 2012
Messages
5,551
Reaction score
5,824
I've heard of an old school approach where the inlay is set a little proud of the surface, then the head stock and inlay are spray painted (black), and then wet sanded to reveal the MoP. Did I hear this right or should I simply mask off the inlay and spray?

Thanks
Mike
No need to do this. Just sand flush as normal and spray the whole thing black. Once the headstock is just dry enough to touch, scrape the black paint off the logo. This is the way Gibson did it back in the day and it works fine. I've done it multiple times. Also make the route larger than the inlay by quite a bit and use black epoxy to fill in. Then you can easily see the edge of the pearl and do not have to worry about scraping the black paint a little further because the epoxy is black also. It's a little time consuming but is quite simple and vintage correct. ;) If you have an extra MOP logo spray a thin coat of clear lacquer on the head stock before the black and push the inlay into the lacquer over the existing inlay. Then you do not have to scrape. Just spray the black and gently pick off the inlay.

Cheers Peter.
 

mness4

Junior Member
Joined
Nov 17, 2020
Messages
26
Reaction score
3
I've done quite a bit of pearl and never had this issue. I use a compressor to blow the rosewood dust off the board and my sandpaper very regularly. I use a radius sanding beam from 80 - 320 grit and even hand sand up to 800 or so, depending on the board. The compressor blows out the dust really well. Have you tried that?

Cheers Peter.

I did not use a compressor since I didn't want the MoP dust to blow around. But I did wipe down with mineral spirits to see if I had any gaps. Once I had the inlays near flush with the board, I wiped with a tack cloth between each grit. I think my problem might have been one or a combo of two things. First, I knocked the inlays down until close to the board using a file skating flush across the inlays (per freddy frets video) before switching to paper. I assume this produced shards rather than powder. If I was not diligent in cleaning prior to switching to 100 grit, I might have pushed those into the wood. Second, although I tried to keep relatively clean sandpaper, it's possible it was not clean enough. Last night I was able to remove most of the embedded dust by using 180 grit with my thumb and sanding around the inlays. It seemed like I had to keep doing this even when moving to 220, so I'm questioning the shards explanation.

I'm building a LP slightly staggered with the SG. The neck uses the same fret board and inlays, so I'll have to watch this more closely. Also, although my SG inlays were pretty tight I found some gaps as I sanded. I had used CA glue for the inlays and tried not to have squeeze out so I could come back later and pack any gaps with rosewood dust. Then I would overcoat with CA and continue sanding. I did not anticipate the MoP sanding dust packing those gaps first, so I had to run the scalpel along the gaps to get that out. It was reasonably effective but not perfect. You can still see a little MoP in the gaps in the image. I think with the LP I'll use some type of epoxy (any epoxy ok?), mix in the rosewood dust, and overfill to encourage squeeze out. That should eliminate that problem if I'm extra messy.

Mike
 

mness4

Junior Member
Joined
Nov 17, 2020
Messages
26
Reaction score
3
No need to do this. Just sand flush as normal and spray the whole thing black. Once the headstock is just dry enough to touch, scrape the black paint off the logo. This is the way Gibson did it back in the day and it works fine. I've done it multiple times. Also make the route larger than the inlay by quite a bit and use black epoxy to fill in. Then you can easily see the edge of the pearl and do not have to worry about scraping the black paint a little further because the epoxy is black also. It's a little time consuming but is quite simple and vintage correct. ;) If you have an extra MOP logo spray a thin coat of clear lacquer on the head stock before the black and push the inlay into the lacquer over the existing inlay. Then you do not have to scrape. Just spray the black and gently pick off the inlay.

Cheers Peter.
I wasn't planning to make an extra logo, but that sounds like a great idea. I am going to use black epoxy, so your other method would work as well. Great suggestions. Thanks.
Mike
 

strayedstrater

Senior Member
Joined
Feb 21, 2014
Messages
371
Reaction score
493
as far as finish....the only times im familiar with a finish being put on a fretboard is when maple is used.
Until recently, Rickenbacker coated their rosewood boards with thick, clear gloss. They sprayed a continuous clear top coat over the entire instrument, then scraped the frets.

They originally used clear conversion varnish but switched to UV cured poly sometime this century. As of August of this year they've stopped finishing the boards on most models.
 

pshupe

Senior Member
Joined
Jan 19, 2012
Messages
5,551
Reaction score
5,824
I did not use a compressor since I didn't want the MoP dust to blow around. But I did wipe down with mineral spirits to see if I had any gaps. Once I had the inlays near flush with the board, I wiped with a tack cloth between each grit. I think my problem might have been one or a combo of two things. First, I knocked the inlays down until close to the board using a file skating flush across the inlays (per freddy frets video) before switching to paper. I assume this produced shards rather than powder. If I was not diligent in cleaning prior to switching to 100 grit, I might have pushed those into the wood. Second, although I tried to keep relatively clean sandpaper, it's possible it was not clean enough. Last night I was able to remove most of the embedded dust by using 180 grit with my thumb and sanding around the inlays. It seemed like I had to keep doing this even when moving to 220, so I'm questioning the shards explanation.

I'm building a LP slightly staggered with the SG. The neck uses the same fret board and inlays, so I'll have to watch this more closely. Also, although my SG inlays were pretty tight I found some gaps as I sanded. I had used CA glue for the inlays and tried not to have squeeze out so I could come back later and pack any gaps with rosewood dust. Then I would overcoat with CA and continue sanding. I did not anticipate the MoP sanding dust packing those gaps first, so I had to run the scalpel along the gaps to get that out. It was reasonably effective but not perfect. You can still see a little MoP in the gaps in the image. I think with the LP I'll use some type of epoxy (any epoxy ok?), mix in the rosewood dust, and overfill to encourage squeeze out. That should eliminate that problem if I'm extra messy.

Mike
Shouldn't be that much MOP dust. If you are concerned, just wear a mask. I cut pearl with my CNC machine and have an air nozzle blowing out the dust. I wear a mask when watching the cuts but don't when sanding fret boards. I probably should but I don't find it creates much dust in the air. Try blowing it out with an air hose, if you have one. Seems like a lot of work to do anything else and as I have said. I have never had an issue and it has never ever crossed my mind to do anything else. If you are doing this all day every day, I may be worried and probably would setup some sort of vacuum. You may want to try that as well, if you have not already. Find a small attachment with a fine brush?

The slower setting epoxy is much better at filling gaps. I have some thick pour stuff that takes about 3 days to cure that works extremely well. I use it for most, if not all, of my inlays. No bubbles or gaps and I don't have to go over it later because of those issues.

Cheers Peter.
 

mness4

Junior Member
Joined
Nov 17, 2020
Messages
26
Reaction score
3
I just completed the inlay sanding on my Les Paul neck, attempting to use what I learned on the SG. It looks much better.

The previous approach: use CA glue under the inlays, trying NOT to have squeeze out so I can pack with rosewood dust and cover with CA prior to final sanding. The inlays were coarsely shaped with a file running along the surface, then they were final sanded using the caul. The result showed two problems. First, the MoP dust/shards embedded in the board. Second, the MoP packed the inlay gaps before I was able to fill with rosewood dust. The latter was irritating but mostly addressed by scarping the dust out with the scalpel and then filling. The former was the bigger issue.

The new approach: I was going to switch to epoxy with rosewood dust and encourage squeeze-out. I decided against this because most of the inlays were very tight and I was not confident I would get squeeze-out all around. This meant MoP dust might still be an issue. With CA, at least I knew the issues. I abandoned the file and started with 100 grit. I kept a close eye on the sandpaper clogging to avoid pressing MoP into the surrounding area. A lot of brushing and vacuuming. When I got close and had the footprint of CA to remove, I switched to 120 keeping and sanded only the inlay using my thumb...no more caul, no more sanding of the field area. And I kept the same attention on removing the MoP dust. What I found particularly useful at this stage was to use a combo of the toothbush to remove the grit and the rubber drumsander eraser to remove the white dust and highlight any remaining CA. It worked really well. In the image you can see the bottom two inlays after the cleaning and the top two before the eraser.

This process may be overkill, but this doesn't strike me as something that is easily avoided...I'm quite surprised that others have never seen this. My current thinking is that there are two main drivers of the problem (at least for me) - the shards from the file need to be cleaned off or else they'll be pressed into the rosewood by the caul, and the sandpaper needs to be pretty clean at all times or else the MoP will be pressed into the rosewood away from the inlays.

...or I just have bad luck.

Mike
20211020_111415.jpg
 

Latest Threads



Top