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3 months ago I tried my first fp finish.
LMI flakes, Kleen Kut D.A., olive oil, one coat a day, out in the garage, so no r.h. or temp regualtion.
Put the git in the house a month and a half ago,
pulled it out today, and noticed crazing all over the spruce.
I did another guitar at the same time, same plank of spruce,
same method, temp, rh,
and it's fine.
Neither are complete yet,
and about the same number of coats.
Any explanation?
Just when I thought I found an enjoyable finish.

I feel your pain Sounds like you have some oil entrapped in the finish. I had a similar problem early in my FP learning curve when I was using mineral oil as the lubricant. I switched to walnut oil, and I only use a few drops per bodying session. Since the switch to walnut oil and very judicious use of it, I have had no problems. Spiriting off with a pad charged with straight alcohol really hardens the finish and brings the excess oil to the surface. There is probably a bit of oil left in the film as an emulsion, but spiriting off removes the "free oil", to coin a term. It takes a knack to know how damp to have the spiriting pad so you only burnish the surface and not attack it with too much alcohol.
Don't give up on FP. What you have experienced is pretty standard for those who are crazy enough to want to master French polishing. The process is pretty much entirely by feel and experience. You can tell when a pad is too wet and should be left to dry a bit, or if you need to move to a fresh part of your pad as it gets glazed over. Sounds like a mystical Zen-like mantra, but "always look for the clouds", meaning the small trace behind your pad that is the alcohol flashing off. No clouds means you aren't French polishing.

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I should have mentioned the denatured alcohol. Probably not the best choice, since there are other solvents in denatured alcohol that evaporate differently than ethyl alcohol. Plus, these toxics may even act as more of a solvent towards the olive oil you used, rendering it more in solution rather than a discreet element.

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I read in another thread that different brands of DA have different denaturants(is that a word?) in them, and some are better than others. Big box brands are probably the worst for variable denaturants.

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I use the 99.9 percent reagent ACS grade stuff from a chemical store... its expensive though, about 3 times the price of the 95% denatured stuff.

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TRein, you probably hit the nail on the head,
because I was just wiping the oil off before the next session.
Also, the d.a. is suspect to me.
When you spirit off,
do you use a new pad with no shellac?
Shoul I strip the finish and start over?
It is the top only,
as the rest is varnish.
Thanks!
I wonder if an online store will send me some Everclear.
Can't get the strong stuff in CA.

I’ve F P finished 13 guitars so far. On one I used Ever Clear and the rest I used D A. and didn’t notice much of a difference I use olive oil for my lube
I haven’t had any problems other than learning how to F P.
I do control the R H in the room that I finish in.
I’m not sure that’s any help but I thought I would through it out there for ya.

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Thanks Dave.
I'm going out right now to get some Startek d.a. just in case.
I'm making a fireplace mantle, and will practice f.p. on that.
I'm sick of the fumes from varnish and polyurethane.

Truer words were never spoken. Add nitro to the list also.
If you have varnish underneath, you should be able to get the shellac off with alcohol. It may dull the surface of the varnish a bit, depending on what you used. If the varnish hardens up after the shellac removal and you can sand it and make powder you should be good to go. Just don't go crazy with the alcohol.
The best results I have had with spiriting off have been with a fresh pad (hunk of old wool sweater wrapped in piece of old cotton t-shirt) and only alcohol. You can see some oil on the surface of the pad as you spirit off. After a bit, switch to a new section of cover and eventually you won't pick up anymore oil or see any clouds. The pad will dry out and you are effectively burnishing the surface.
Lowe's sells a denatured alcohol that is supposedly "green", with a minimum amount of toxics added. It was written up by Mottola in AL a few issues ago. If I could not get ethyl alcohol, that is what I'd use.

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I take it the whole guitar is FP. Did the crazing occur only on the spruce top? If so it is most likely not the materials or the process. If the crazing occurred on the spruce top only and not the back and sides or the spruce sample board, to me that sounds more like RH issues. The spruce has expanded/contracted beyond the coatings elastic limits. A mouse loaded with mostly alcohol and a touch of shellac and a good bit of elbow grease and you should be able to re-amalgamate the shellac.

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Brian, the back/sides and neck are varnish,
and the top is f. p.
Do you think the rh while polishing affected it,
or the changing rh afterwards?
The rh has gone done here,
as usual, in the winter.

+1 Brian's comment.
D.

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