Swirl elimination

[Kary Karahadian]

My last 8 finishes have been French Polish and after glazing and letting the instrument sit for 7 days I've used first McGuire's 7 and then tried Novus. In my hands, both products have left swirls that are visible when light is reflected off the surface. Anyone experienced similar?

[Michael Lewis]

Polish on top of French polish? The French polish is supposed to be the final coat, as is done by many who use oil varnish on instreuments. There should be no need for anything over the light and glossy coat of shellac.

Are the swirls coming from the added polish of are they in the shellac? If the former then omit the former, but if the latter then you need to gain a bit more skill so you don't leave the swirls.

[Kary Karahadian]

I model my technique after the Milburn tutorial in which they advocate McGuire's #7 a few days after glazing. It does seem to eliminate that very last bit of haziness that i seem to have left after glazing, sharpening up reflections off the surface, but it does impart a swirl effect from the fine abrasive when viewed in reflected light. I've just never been able to get that level of clarity with glazing alone.

[Mario Proulx]

There's nothing 'wrong' with polishing a FP finish; many of us do that. I've had great success doing so with Meguiar's #9 first, then followed with #7. #7 actually doesn't have any abrasive in it, if I remember correctly. You can also try an old favorite recipe, being equal parts #9, water, and mineral oil. Make-up a small bottle to try; the mix will separate quickly, but just be sure to shake the bottle each time. And finally, look at your polishing cloth; that might be what's creating the swirls in the first place! Oh, and technique; do NOT bear-down on the cloth at all; make a large wad of it, and be gentle.

[Kary Karahadian]

Mario, your advice was spot on! Coincidentally David Schramm, a classical builder, was over today checking out my two new guitars. He also suggested that the cloth could be the culprit. i switched to a microfibre cloth from OSH and used very light pressure. Swirls are gone. Thanks!

[Mario Proulx]

Bingo! Glad I was able to help!