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  #1  
Old 11-10-2013, 06:16 AM
joeguam joeguam is offline
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Default Repair: CA Glue Drop-Fill in UV-Cured High Gloss Finish

About a year ago, I was using this stewmac bridge pin puller for the first time...



...when it slipped off the bridge pin and skipped its way across the soft sitka spruce top of my custom ukulele, gouging into the finish and denting the wood...



I immediately took a wet cloth, fired up my soldering iron and steamed the dent in the wood back up to the surface. However, it left this nasty gouge in the UV-cured high gloss finish - the same finish Taylor Guitars uses in their high gloss models.

Not knowing much about repairs back then, I turned to the AGF and posted this thread: Taylor Gloss Drop Fills?

So because there are no professional luthier services where I live, if I wanted to repair this, I was going to have to figure out how to do it myself. I did a lot of online research, mainly coming across these two resources:
StewMac: Fixing a small chip in a guitar finish
Frets.com: Drop Filling Lacquer

Following their method, I attempted the process on a less-expensive instrument and achieve great results. I documented the steps in this thread: Repair: Fixing Lower Bout & Waist Cracks (Ukulele)

So this thread will detail the steps I took to repair this mishap. And for the record, the bridge pin puller went straight into the trash can and I reverted back to using diagonal wire cutters like Taylor Guitars recommends in their instructional videos on YouTube (I don't know why I ever switched, it was working perfectly).

I take the time to document this process in hopes that someone will find this information useful. Your thoughts, suggestions or advice is very welcomed along the way!

Cheers!

...
Joe
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Old 11-10-2013, 06:29 AM
joeguam joeguam is offline
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I started the process by cleaning the area with a mixture of water and light dishwashing soap. Then, I wiped it once over with naphtha. To start the first dropfill, I used the stewmac #10 thin viscosity CA glue:



Using the pipette that came with the glue, I slowly laid a bead into the crack enough for it to sit proud of the surface.



After about an hour or so, the CA glue sucked it's way into the crevices of the crack below the surface.



So, I repeated the process with the #10 CA glue 3 more times over a span of 24 hours until I was confident no more glue could be absorbed within the crack. Then, I switched to the #20 medium viscosity CA glue and laid one last layer proud of the surface.



As you can see in the 2nd picture, I found another ding just off to the right, probably from a hard strum or something. I decided to incorporate it into this repair.

The next step is to use a taped razor blade to level the proud heap of glue.

...
Joe
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  #3  
Old 11-10-2013, 06:51 AM
joeguam joeguam is offline
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Using Frank Ford's razor blade scraping method, I worked slowly and gently to level the CA glue.



Next, I strip-sanded with 240-grit, block sanded with a small eraser and 400, 600, then 1500 grit.



Here's what it looks like after wiping it with just a damp paper towel, very promising!



The next step is to go up the series of micromesh paper and wet-sand to a shine that's ready for buffing.

Cheers everyone!

...
Joe
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Old 11-10-2013, 07:48 AM
terryj47 terryj47 is offline
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Very nice!
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Old 11-10-2013, 01:04 PM
Ned Milburn Ned Milburn is offline
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Looking good, Joe!
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Old 11-10-2013, 07:27 PM
joeguam joeguam is offline
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Thanks Ned, I owe a lot of what I now about this process to you too!

The next step in the process was to wet-sand up the micromesh series: 1500, 1800, 2400, 3200, 3600, 4000, 6000, 12000. I moved in all different directions to spread the scratches around as best I could. Here's what it looks like after half-way through the process, its getting there nicely.



When I finished with the 12000 grit, I use a high-gloss polishing compound and a paper towel to to buff out as many fine scratches as I could by hand.



Here are some shots of the job all done. Considering I am my own customer, I'm very happy with the results as it looks much better than it was before.







The two dark spots or blemishes that you see in the picture are actually from the gouge in the wood itself, below the finish. There's really nothing I can do about that as I don't have the means to take off the finish to sand the wood uniform then refinish it with the UV-cured high gloss. So, I'll just have to live with it, but I'm actually okay with it as it give it it's first battle scars.

As a final send-off, here is the before/after for comparison.



Cheers everyone, comments or suggestions are welcomed. If there's anyone who has any questions (maybe you're thinking about doing this yourself), just know that I am not a luthier, just have some experience woodworking as a hobby.

...
Joe
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  #7  
Old 11-10-2013, 08:11 PM
Michaelmsg Michaelmsg is offline
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Joe, I fully feel your pain. My first acoustic guitar that I built while at Charles Fox's shop which was also my first lacquer finish, was also affected by this same mishap with the exact same tool. I don't use this type of tool any longer either. Unfortunatly my scratch/indention was much more severe. This became my very first lacquer repair as well. It did not turn out perfect but from head on you can not see the damage/repair, but from an angle the light reflects differently on the previous scratch.

Nice Job, thanks for sharing. Now I don't feel so bad. I thought I was the only person to ever have this happen to.
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  #8  
Old 11-10-2013, 09:44 PM
joeguam joeguam is offline
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Default Repair: CA Glue Drop-Fill in UV-Cured High Gloss Finish

Yeah Michael, my heart about dropped down to the floor the second it happened. This is a fully custom uke with my name inlayed in tribal on the fretboard, built for me by Joe Souza from Kanile'a himself - it is essentially my most prized instrument. You can only imagine how I felt!

I'm just glad its back to a nice look!

...
Joe
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  #9  
Old 11-11-2013, 12:29 AM
Michaelmsg Michaelmsg is offline
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Yes I know exactly how you felt. It is not a good feeling.
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  #10  
Old 05-30-2014, 12:19 AM
DesertTwang DesertTwang is offline
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I had no idea there was such a thing as a custom ukulele... Learn something new every day.
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  #11  
Old 05-30-2014, 05:04 AM
Arthur Blake Arthur Blake is offline
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Default Push out pins

Beautiful repair, and very nice top.

Just wondering about the need for pin pullers. I suppose people change one at a time, or the sound hole in a uke is smaller than guitar, but I always push up with my fingers from the inside eliminating the need for pin pullers.
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  #12  
Old 05-30-2014, 07:17 AM
joeguam joeguam is offline
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Yeah, I'm not sure why I even tried the pin pullers out. Oh well, now I'm very confident in the drop fill process.
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  #13  
Old 05-30-2014, 12:45 PM
Halcyon/Tinker Halcyon/Tinker is offline
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Well done. Looks as if you did it as well as it could be done, congrats!
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  #14  
Old 07-12-2020, 12:11 AM
Rinaz Rinaz is offline
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Sorry to comment on an old thread, but this helps me a lot. I want my guitar to look perfectly good, I keep it in the case all the time but you know... it happened. So I don't know how to thank you enough, great guidance!!

I have a question is that what kind of sandpaper do you use to strip-sanded the finish? or any sandpaper will work?

Last edited by Rinaz; 07-12-2020 at 03:18 AM.
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  #15  
Old 07-12-2020, 08:17 AM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by Rinaz View Post
I have a question is that what kind of sandpaper do you use to strip-sanded the finish? or any sandpaper will work?
He clearly stated the sequence and sandpaper:

Quote:
Originally Posted by joeguam View Post
The next step in the process was to wet-sand up the micromesh series: 1500, 1800, 2400, 3200, 3600, 4000, 6000, 12000. ...

When I finished with the 12000 grit, I use a high-gloss polishing compound and a paper towel to to buff out as many fine scratches as I could by hand.

https://micro-surface.com/micro-mesh-types
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Tags
ca glue, dropfill, taylor uv gloss

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