How do you clean dried CA glue out of fret slots?

[Tom Haywood]

If you glue down frets with CA, how do you clean the slots when you re-fret? There's no way to do a clean re-saw on this one without pulling the binding. Trying to pick it out and/or cut through it with a slot cleaning file is adding an hour or more to the project just to clean four slots that have glue. And, it risks chipping the ebony. Acetone is not an option because it will melt and/or loosen the binding.

What am I missing?

[pops1]

StuMac has a fret slot cleaning tool that I use, I also I took a small saw blade and broke it into short pieces for just this purpose.

[Marty Jacobson]

With one of these: https://www.stewmac.com/Luthier_Tool...ning_Tool.html

Or make your own... just sand a hook shape into a .020" thick piece of steel shim stock and then sharpen the end so you can scrape with it. Or people (probably Frank Ford IIRC) have used those X-acto razor saws with the blade broken so you only have 3-4 teeth, and then scrape with that. Same thing as this tool S-M also sell.



This thing is also super slick... maybe some ideas here for tools you could make yourself.

[Tom Haywood]

Thanks, Pops1 and Marty. Actually, I have these tools in addition to some I've made, and I had tried them before posting the question. The best tools for me are turning out to be an old exacto knife (triangular blade) and a box cutter, followed by an old nut slot saw I made from a feeler gauge.

I generally don't use glue to hold frets and I haven't encountered this before with repairs, yet I've seen it casually recommended quite often to wick CA around the frets when installing them. In addition to taking forever to get the hard, dried glue out, despite normal precautions the edges of the slots that were glued chipped deeply when the frets were pulled. I guess I'm just reacting to what seems like a huge amount of additional work caused by the glue, and hoping that those who use the CA regularly for this have a solution that makes it easier.

I'll quit whining now and get back to cutting and scraping.

[Ward Elliott]

I would guess that if you found that much glue in the slots the previous repair person may have used medium thickness or even gel superglue and put it in the slot before putting the fret in. If you use the thin superglue and wick it in under the installed fret you will never get that kind of build-up in the slot. I have much more of a problem with replacing frets that have been put in with yellow glue! It makes a mess that can be a lot of work to get out of a bound fingerboard. But when I have replaced frets that I previously wicked thin superglue under I don't find any sign of glue at all.

[Wrnchbndr]

I've made a number of fret slot tools. The picture posted by Marty has what I believe is actually a nut slot saw from stewmac modified to be fret slot depth saw and I've done exactly the same thing. Those saws are inexpensive and available in a number of kerf widths so you can buy a couple of them and cut off sections of the blade and make your own small length blades and install them into handles with what ever scrap you have on hand. I typically use drum sticks, violin/cello pegs or whatever might be on hand. Feeler gauge stock is available from McMasterCarr. Some of these tools become your most valuable.

[rcc56]

A common method is to use a Dremel in a small router base with either a conical bit such as the Stew-mac #1180, or the ~.020" or .022" burr of your choice from a jeweler's supply house. If you use the Stew-mac bit, you can re-taper it on a sharpening stone to reduce the diameter if necessary.

This is a well-known and common technique, introduced in Don Teeter's book several decades ago. It's easy to control. If you're afraid of removing too much material, start with an .018" bit.

The bit will follow the slot. Sometimes you have to make a shallow first pass followed by a deeper second pass. Keep the tool moving, but don't push too hard or you might break the bit.

I believe that CA tends to make the edges of the fret slots brittle. I prefer to use Titebond liquid hide glue when I do a re-fret. I only use CA for loose ends on an existing fret job, and if there are more than 3 or 4 loose ends on an instrument, I generally recommend that it should be re-fretted.

[Marty Jacobson]

What about melting the glue out with a heated feeler gauge?

[pops1]

I like to file the top of the slot with a triangular file before fretting to make a slight bevel so to avoid chipout in the future. If you pull the first fret and find glue, use a soldering gun with the tip cut off where the two pieces coming from the gun come together at the tip. You can now pull the two remaining pieces to the edges of the fret. I usually file them concave so they fit nicely on the fret. Apply a bit of solder to the contact point at each end and heat the fret before pulling and it will not tear out as much and release the glue.

[Wrnchbndr]

Great posts. Its amazing how much you learn and then forget. I've done clean-out with a dremel. Heating up a hooked shaped feeler gauge sounds like it would work too.

[Tom Haywood]

Great ideas and advice. Here's what I got the most mileage out of:



I think Ward had it right - medium or thick viscosity CA was used. Digging and sawing wound up being good, because it showed me what had happened. The four slots that had been glued all were too shallow at the ends. This may have caused the frets to push up, and lots of glue was used to try and hold them down. All that ebony beneath the glue was the difficulty. I cut it down to the appropriate depth and all is well. I did heat each fret until quite hot before pulling. All came out very clean except the glued ones. The slots were slightly chamfered, so I think the thick CA explains the tear out.

Good lessons here. I'll be more prepared for this in the future. No glue was used to install the new frets.

[Tom Haywood]

Update. I did have to glue the 12th fret after all. Combining techniques mentioned here and in another recent thread, I wicked super thin CA near the ends of the frets, wiped the board immediately with a paper towel, and hand pressed for about 30 seconds. It left a perfectly clean and solid result. Thanks again to everyone for the good lessons.

[Tavy]

I'm with Marty: put a heated flat metal strip in there and the CA will basically evaporate. Watch out for those fumes though!!

[rcc56]

I'm with Marty: put a heated flat metal strip in there and the CA will basically evaporate. Watch out for those fumes though!!

This is one of the reasons I seek other alternatives first and only use CA as a last resort. Sooner or later, someone will have to work on the instrument again.