Official Luthiers Forum!

Hello All,

I am trying to finish my first guitar, I've coated with system 3 Epoxy thinking I would coat with KTM-9....I've changed gears a bit and would like to use the Zinsser french polish. Can I put the french polish over the epoxy that is already on the guitar? How many coats? Best way to apply it? Time between coats...etc. I looked through the archives and still am not real sure about the whole process so any advice would be greatly appreciated.

Thanks,
Greg

_________________
Gwaltney Guitars

Yes. There is no issue with shellac adhering to epoxy. I would light sand with 400 and clean with DA prior to french polishing.

That said never try to apply epoxy over shellac. This is a problem getting a good bond

Greg,
I had very good luck with applying FP over epoxy. However, I wouldn't use the FP in a can. You might want to mix your own shellac. Use a 1 lb cut through the whole process with very light coats, and I think you will get better results. Just my opinion, but FP is very forgiving, so any method will work. The reason I don't like the FP in a can is because it already mixes the oil in with the mixture. You really don't need the oil until the bodying stage, and even then, very little if you use a 1 lb cut. I say you should buy some shellac flakes and get you some everclear and mix your own.
Tracy

I agree with Tracy except I have very good results with Zinzzer's Bull's Eye SEAL COAT 100% wax free Universal sanding sealer (not Sanding Sealer). It is a 3# cut of 50% amber and 50% extra blond in an alcohol solvent pre cut and 100% wax free and no oil added. I to like to add a drop of oil to the pad as needed for lubercant but I don't want it in my mix. I have mixed my own 2# cuts for years till I read Frank Ford's artical on Zinzzer's Seal Coat. Then I gave it two tries and have never switched back. It is a bit more amber tint than self mixed extra blonde but give a very nice vintage look. It keep well for a year if properly sealed.

This stuff
MichaelP38666.5279398148

Michael,
Right on! I haven't tried that yet, but it is on my list. Another good point is that you don't want wax in the shellac because it may not adhere to the epoxy. Greg could just buy some of the stuff you show above and brush on with foam brush 2 coats a day over a 3 day period, then wait 2 weeks, then level and polish. This way he will get a nice film finish and not hand work. I did that on my neck, and it worked beautifully. I love the feel of a shellac neck. Anyway, so many ways to skin this cat.
Tracy

I have used both the Zinsser Seal Coat and the Zinsser French Polish, both
work great. The FP has a very nice super-blonde tint, alomost 100% clear. I
am not finding the parafin in the finish to be a problem, it goes to the
surface and a wipe of naphta takes care of it, like some have suggested on
thsi forum. I find it easier to build thicker coats with what's in the FP can,
maybe because of the lubricant? It appears to dry and harden much quicker
than the seal coat too.

_________________
Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

I have used both. I had no issue with paraffin in the FP either. I just prefer to add my own oil to my muneca as I go. That and I like the slight amber tint of the Seal Coat, but that is just a personal preference thing. Also it allows me to have on product for both French polishing and to spray as a sealer. I have to say I did not notice any major dry time differences. but probably did not pay that much attention to it

[QUOTE=MichaelP] I have to say I did not notice any major dry time
differences. but probably did not pay that much attention to it[/QUOTE]

It is probably my own inexperience with the whole FP thing, I still cannot get
a clean lustre without wet sanding and polishing afterwards. The muneca, or
the way I load it and apply the shellac rather, still leaves traces I have to buff
out. Oh well, who said one can learn FP in a pinch?

_________________
Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Laurent, what are you using for both the inner and outer pads?

[QUOTE=MichaelP] Laurent, what are you using for both the inner and outer
pads?[/QUOTE]

Old 100% cotton T-shirt material for the outside and 3 100% wool circles
stitched together for the inside. Wrapped tight and loaded the muneca is
maybe 1" wide.

_________________
Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

[QUOTE=MichaelP]Also it allows me to have on product for both French
polishing and to spray as a sealer.[/QUOTE]

Michael, how are you spraying shellac? Doesn't it have a tendency to run
much more easily than lacquer, for example? I gave up on the muneca for
my current project and have much better result with a brush… Very, very
sad…

_________________
Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Laurent,
Sorry I missed this post but I was gone for a week.

I spray the Zinzzer's Seal Coat uncut with a el-cheapo
hvlp setup I restrict the flow till I have a wet but fine mist. It needs to go on a bit finer than lacquer to avoid runs, but it is not a big issue if you don't spray too wet.

Sorry to here that you are giving up on the muneca. I suspect that you may be over loading in the amount or cut of shellac in the muneca when spiriting and glazing. At the glazing stage you are refining the film that is in place, so a lighter cut and less shellac is needed. in return a higher percentage of solvent is needed to help refine the film surface. The combo of a thinner cut and the stropping motion of glazing will get you there. However there is nothing wrong with brushing, but I can't believe you are able to build a more level film brushing than rubbed. not a criticism just a curious thought