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Hi,

I’m in the process of sanding this DN body and the sanding reveals stains of CA glue around the bindings and rosette in some spots. I have sanded quite a bit with 120 grit and stains are still remaining. I’m scared I will remove too much material if I carry on. I’m planning to do a tru oil finish and I tested it under the fretboard extension to see if it would hide anything by making the redwood top a little darker and it does to a certain extent but not as much as I would like to. I think I will keep sanding but I’m not sure how much more I can safely remove. Any advice?

The CA wicked into the wood capillaries. You won’t be able to sand it out. Quit while you’re ahead. After the Tru-Oil, you will notice. Others won’t.

As Mr. Graham said, the staining is permanent because the CA wicks in via the end grain. In the future, a couple coats of 2 lb cut super blonde shellac will seal that end grain against CA, and the shellac itself will bond well with the glue. We routinely used super-thin CA for bonding purfling into place, and - provided the wood was sealed with shellac - we never had any staining issues.

For what it is worth, shell really wants to have a visual border with surrounding structure... even a thin .010 purfling line will allow the eye to better see the shell as a discrete element of the composition, but a BWB or adding color to the fiber/wood purfling stack can add some additional visual interest.

In terms of process, for most linear shell work we built up the binding and fiber/wood purflings using a .063 width UHMW plastic filler strip in place of the shell, then snapped in the shell after the filler strips were pulled. This approach allows a little more time to match the shell segments up, and without the press of time as glue sets, the shell purling may be installed, adjusted, and then glued in place. Leveling the shell with plane and scraper (to take the fiber and binding down close to shell) and ROS also removed the excess shellac on the body in preparation for final blocking and fill/finish.

Remember to seal the edges and rosette area of the body before milling the binding channels - both for the crisper edges produced and for scruff/scrape protection on softer top woods like redwood and cedar. After refreshing the shellac on the purfling channels, the body is ready for binding and purfling fit-up and glue-up. Shellac also makes any tape used to position or hold binding in place stick better to body woods and limits fiber pull-outs on top woods.

Edit: When shellacking the binding/purfling and rosette channels, brush on, let it sit for a minute or so to penetrate, then wipe off the excess... this should minimize any buildup.

Stop sanding, you will not be able to sand that out. CA will wick into the endgrain of softwoods and the stain goes all the way through. Fortunately, it doesn't look too extensive in this case. Once your finish goes on, it should be less noticeable. You will be tempted to point it out to everyone you show your guitar to, don't; Most people will not notice. It may drive you crazy but most people will have no idea.

A couple coats of shellac in the binding channel and rosette channel will prevent this staining. I avoid the shellac if I am using waterbased glue but always use it if I am doing CA. I usually fit my rosette channel as tightly as I can, then decide what glue to use. If I get a really tight fit, I shellac and use CA. If it is just a little bit looser than I want, I use waterbased glue because I know it will swell the material slightly. The trick is remembering to use the shellac; If I forget, I'm in trouble. . . I may have a rosette out there with a wider than planned pattern. . .

Edit: I'm usually good about reading before I respond. I didn't do that this time. Looks like everything I had to say had already been said.

_________________
Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

It never hurts to foot-stomp a point that will save someone the effort of continually pointing out the 'invisible to anyone else' error they made fifteen years ago on one of their first guitar builds.

Note: This is my vote to finish your existing instrument and resist the temptation to self-report the binding snurble

Thanks all for the good advices!

I was initially planning to use the teflon strip method to glue the zipflex strips but I was advised it wasn't worth the trouble. Instead, I first taped bindings and purflings in place with fiber glass reinforced tape and then glued everything together with CA which allows for plenty of time to set everything safely in place. But I've never heard of UHMV and I assume it's the same kind of deal then with teflon that doesn't stick to CA glue.

I was also under the impression that sealing with shellac would slightly thicken the binding/purfling channels which I thought had to be avoided. But I'll certainly take this precaution next time!

Yes, seal with shellac, no downsides that I have experienced.

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http://www.Harvestmoonguitars.com

Time to give a sunburst a go.

That’s what I would do also. Or at minimum, a shade around the edge.

Mine's worse Dye from cheap black paper wicked into spruce. I thought it would be cool to make super thin purflings with it and some butternut truss rod slot wood chips I saved, but sadly I don't think it was even any thinner than the .010" black fiber I have from LMI, so I could have used that. I've been fretting over it for 6 years now and finally decided to ignore it and finish the thing. I wanted to cover it up with some sort of sunburst type effect, masked so it's only inside the purfling, but I think it would be too much trouble for something that probably won't come out quite like I want anyway. I also considered carefully carving out the two or three worst grain lines and gluing in little bits of fresh spruce, but I think the glue lines would draw just as much attention as the stains.

Sometimes it’s just best to learn your lesson and move on…

Ha! Can't argue there!

_________________
Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.