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I just completed 5 glazing sessions over the past 2 days. The surface looks significantly improved over that following the bodying sessions. The surface, while it is quite reflective (about halfway between satin and glossy), I'd like to get more glossy. If I look closely I can see micro lines running along the grain (presumably from the muneca tecture). Are there any further steps that others have taken to get the surface to the next level?

The Milburns describe the use of MacGuires #7 and #9 but I'd like to wait 2 weeks before trying this. Also, has anyone ever used Menzerna fine and extra-fine on a buffing wheel?

Any advice will be appreciated. TIA

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JJ
Napa, CA
http://www.DonohueGuitars.com

Let me guess you are using tee-shirt stock for you outer cover. While it is mostly lint free it does have ridges in it that can leave patterns in the shellac if you have not perfected the spiriting off or stiffing off process. I much prefer fine muslin for my outer cover, but if you continue glazing with the very light cut of shellac and a higher percentage of alcohol using only straight passes and over lapping every pass you will melt down the ridges you see. you can, if patent achieve a very high gloss but that will not happen till you achive a melted level film then polished it via glazing. Remember to glide on and glide off keeping the stoke moving at all times like buffing shoes. you will get there. If any conselation I never count my glazing session. I just do it till I am happy. I will tell you that it will take less on your next project but the first couple you are just learning the tecneque.

Thanks, Michael! Yes, I have been using the tee shirt material. I'm determined to get this one right so I'll continue to do more glazing sessions with the fine muslin. Do I need to return to muslin bodying sessions or will glazing with muslin get it smoothed out?

I've learned so much with this first attempt and much of that has been possible only through your advice and encouragement. Even though I've read the Milburn tutorial and purchased Robbie's CD, having the ability to get immediate feedback on specific issues from the resident expert (you) has been the most help for me. It is definitely a technique that requires patience and discipline but I believe the results are worthwhile. I'm doing this on a very special set of waterfall bubinga and I want the finish to be perfect. The Zootman and Steve K. are counting on me to show this set off to its greatest potential.

Right now, I need to rest my "FP elbow" so I can swing a club in the club championship this weekend...I'll continue the sessions next week.

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JJ
Napa, CA
http://www.DonohueGuitars.com

JJ I see no reason to add boding sessions. The issue is the high ridges need melting down. You might want to do a couple stiffing-off sessions with a muslin outer cover (also known as spiriting-off because your load is more solvent than shellac therefore the load is more like a reduced varnish than a boding FP load). Remember use no more shellac in the inner pad just add 5 or 6 drops of alcohol and smear 1 drop of oil on the pad. The object is to melt the high ridges. not to add more shellac. Use straight sort of firm but quick strokes starting at edge of the LB and stroking twoard the edge of the UB or vise versa, again glide on, glide off. over lap thees passes by about 50%. start in the middle of the guitar and work toward an edge, then repeat and work toward the other edge. This should flatten out the film in about 2-3 sessions. You will have to restart you glazing because this will dull what you have polished, but this is the proper way to solve the ridges issue.

Here again on future project I really suggest that after the second body session and after every body session there after you stiff-off just as I have explained above (allow the body session to harden 15 min prior to stiffing-off). By doing this you are leveling the film as you build it. Doing this you will recoup the stiffing time by eliminating the need to level prior to glazing.

P.S.
The reason you want the body session to harden prior to stiffing or spiriting off is that you want to only melt the high spots not the total film surface.MichaelP38951.5175231481

I think it's starting to set in with my dense brain! I will do the stiffing sessions with the muslin material I just purchased at the local fabric store. I got 2 types:
1) Muslin...unrefined cotton that has a standard cross weave much different from that of tee shirt material...no ridges
2) Quilting Cotton...more refined cotton, finer weave and lighter in weight.

I'll try both and see which works best. I may be tempted to do this tonight in spite of the FP elbow

I know the second guitar FPing is going to go a lot more efficiently that this first experiment.

Thanks again, Michael!

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JJ
Napa, CA
http://www.DonohueGuitars.com

The 15th FP project will be amazing The more you get familiar with the process and the media the more refined your technique will become.MichaelP38951.538275463

Michael:

Thanks for the tip on the muslin - I had been using T-shirt material. After reading your post, I went and got some yesterday - Far superior!

Thanks again for the tip!

-Mark

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Michael...The "corrective sessions" worked perfectly!!! And the muslin made a significant difference. I initially tried doing the stiffing sessions to knock down the ridges but was unsuccessful. It required a few more bodying sessions to actually fill in the valleys. This time I stiffed with alcohol afer each bodying session and it smoothed the surface a lot more efficiently.

Once level, I glazed using the finer quilting cotton material. I now have a smooth and shiney surface...not perfect, but a LOT better than before. In retrospect, I suspect that my pore filling (Zpoxy) and surface prep techniques were inadequate for FP. It may well be that the micro-ridges were actually sanding ridges. Next time, I plan to prepare the surface to 600-800 grit and then pore fill with pumice. I stopped at 320 on this one as I did on lacquer finishing. I need to refine my FP state of mind and forget past finishing techniques.

I'm going to wait a week and then try polishing with McGuires #7 and possibly #9 as recommended by the Milburns. I used #7 on the top and it looks great. No ridging problems there but then again, I prepped that surface to 600 grit!

Another question...has anyone ever used a buffing wheel with Menzerna compounds to polish a FP surface?

Michael...thanks a million for your tutoring so far and thanks in advance for addressing the continuing questions I'll have as I continue my learning process.

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JJ
Napa, CA
http://www.DonohueGuitars.com

My pleasure. By the way on the Zpoxy fill. Sand just to the wood removing the outer film near completely with 220/320 then come back with 400 to clean the surface smooth as a babys bottom. No need to go greater than 400p prior to FP but it does need to be consistanly level and free of scratches. The Zpoxy in the pores is still there just not the surface film.

If this was getting a KTM9 or nitro finish in stead of FP, at this point I would wipe a wash coat of a 60/40 mix of DA/Zpoxy over the body then seal with #2 cut of shellac.MichaelP38953.4016203704