anyone use these for touching up nitro based finishes?

[darylcrisp]

have a near new collings mandolin brought to me for a setup, and to remove some very slight finishing swirls. the man cleaned his frets with steel wool at some point and took a cloth and removed the leftover from the body and glossed headstock. this resulted in lots of little micro scratches on the body in places and the headstock.

i am novice at finish work, but this email arrived today and these look good, wondering if anyone has used them, results? thoughts?
https://www.stewmac.com/Luthier_Tool...414_B_20190303

any other suggestions very welcome. the swirls and scratches appear under light and not so much general use, but they are there, hundreds of them. poor guy is upset with himself massively.

anyone use these products?
https://www.stewmac.com/Materials_an..._of_2_8oz.html

https://www.stewmac.com/Materials_an...Compounds.html

thank you
d

[sunburst]

I went to the trouble of clicking the links and I don't use any of those products.
You can easily remove the scratches by hand rubbing with a good quality fine polish, and at least one of those Stewmac products would probably be good, but as I said, I don't use them so I can't say with any authority.
Here is my polish of choice:
https://www.novuspolish.com/fine_scratch_remover.html

[sliebers]

I would suggest getting some Novus #2 plastic polish and do the buffing by hand, unless it's too severe. There's also a #1 Novus for heavier scratches. My fear of using an electric buffer of any sort would be burning through the finish. Going by hand, you can get a feel for how much you are taking off. Some brands of instruments you could do with machine and not worry as the finish is quite thick. I'm guessing the Collings is a very thin finish?

I think the Stew Mac polishes are just rebranded Mequiar's. I've found the swirl remover doesn't do much. I can get way better results by hand with Novus #2.

[bpatrick]

The foam pads and Stewmac polishes will likely do the trick, but you might try a more gentle hand rubbing with a soft old cotton t shirt first. I've used Meguiar's M2 Mirror Glaze Fine-Cut Cleaner followed by Meguiar's Glaze Swirl Remover 2.0 to final polish new instruments as part of the final finishing process. The Stew Mac polishes are likely repackaged Meguiar's or similar auto body polish.

I'd guess that the Glaze Swirl Remover and/or Fine Cut Cleaner polished by hand will do the trick. If you need to be a bit more aggressive, you could use foam pads or similar wool polishing pads. I would start by going easy in the least conspicuous area and fine tune the methods from there.

[darylcrisp]

I went to the trouble of clicking the links and I don't use any of those products.
You can easily remove the scratches by hand rubbing with a good quality fine polish, and at least one of those Stewmac products would probably be good, but as I said, I don't use them so I can't say with any authority.
Here is my polish of choice:
https://www.novuspolish.com/fine_scratch_remover.html

as always, thank you very much for joining in this thread John. Novus products have been ordered.

[darylcrisp]

thank you everyone. i had never heard of the Novus products, they sound excellent, and i ordered up the 8oz tri pack of all grades.
this forum is such a fine place to find and learn what you need to do or know.

d

[Bob Schmidt]

I've never used Novus on lacquer, but it works well on eisenglass so I would guess it is fine for lacquer. I use automotive compounds; either 3M perfect it, or as suggested, Maguiar's fine cut compound. They work equally well on nitrocellulose lacquer and automotive finishes. I would also avoid any machine polishing unless absolutely necessary. You have a better feel for how much you are removing by hand.

[Marty Jacobson]

The foam pads do work. I would not recommend them, but I polished a blacktop up pretty nicely after a rattlecan lacquer job fifteen years ago with those things.


A few caveats:
1. They make a HUGE mess. Spraying fine splatters of compound into every nook and cranny of the instrument. I'd not recommend using it for your Collings touch-up for this reason, there will be a lot of white under the fretboard extension, all around the inside of the f-holes, etc. This is one reason why a dry polishing compound on a buffer is far superior. It still gets everywhere, but is more or less brush-off-able, while the liquid stuff is much more tenacious.
2. You can burn through a finish pretty quickly, especially if there's a shellac seal coat.
3. Did I mention they make a huge mess?

I pretty much always buff up peoples instruments when they come in for a setup, the scratches you're talking about would be two minutes on my buffing setup, with little or no risk. If you're going to be doing setups, you're going to be dealing with this kind of thing. I'd definitely get a bottle of Maguiar's Fine Cut Cleaner and Swirl Remover, that and a microfiber pad or old t-shirt will do just as well, just with more elbow grease.