French polish...almost there but need pointers please

[Eric Thumb]

IMG_0919.jpg


Hopefully this picture uploads.

I've spent the last month trying to figure out shellac. It all started when I had the bright idea to use something other than nitro lacquer. I read enough of the "you're killing the environment" and "your garage is gonna explode" threads to make me venture out of my comfort zone and try something new. Soooo I ordered some super blonde flakes and some DNA and figured that it couldn't be THAT hard.

Long story short.......on about page 210 in the finishing forum I came across a thread about French polishing that made me realize that I was using too much shellac/DNA in my pad and that mineral oil might be a good idea. I've since adjusted my technique and I think that I may be getting onto something.

Anyway I seem to be getting the gloss that I am after but I am also getting the grain of the wood (maple in this case) to show through the finish. I am going for a glass smooth, blemish free surface. Do I just need to sand it back and keep doing what I have been or is there a trick? (and by trick I mean something that is glaringly apparent to the normal person but I have not caught onto yet). I did sand the board down with 220 and after building up a few coats sanded it with some WELL USED 600 wet/dry. I still had some grain showing after the 600 so that is probably why I haven't achieved what I'm after just yet.

Would a grain filler make life easier? I've never used it and honestly have no idea how it works. Does it obscure the grain? How about lacquer sanding sealer? I've also read about 4f pumice being used somewhere in the steps to getting a french polish but I've never used that either.

Any suggestions are VERY appreciated.

Thanks,

Eric

[John Coloccia]

Well well well well well....it's always difficult to be 100% sure, but I believe what you're seeing raised grain from the alcohol because alcohol LOVES water, and it's probably sopping wet in Indiana right about now, plus your DNA probably had some water in it to begin with, depending on what exactly you came up with for DNA. My sense tells me that you'll have to sand it back lightly until you're smooth again and continue on. You may go down to the wood in some spots. It's just as well as I gather your arm is still attached, and you haven't French Polished properly until your arm has fallen off

Pumice won't help you. You use that to fill an open grain wood, like rosewood and mahogany for example. This is a completely different problem. Maple never requires grain filling.

BTW, don't ever use worn sandpaper, especially when you're working with finish. It doesn't make smaller scratches. It just makes less but potentially deeper scratches of whatever grit you choose. This is really obvious with really coarse sandpaper (you can actually see it wearing out by watching the grit disappear), but it's no less true for finer grits.

Anyhow, the beauty of French Polish is it's nearly impossibly to actually screw it up. Unless you REALLY make a complete mess of things, and there's normally not enough "stuff" in the muneca at any one time to make such a mess, the worst you really do when you botch it up is just add a little work and it takes a little longer. My opinion based on what I see is to flatten it and then continue on with bodying sessions.

[Scott Holmes]

You are not "French Polishing" anything. You are padding shellac. If you aren't using pumice in the first few sessions you aren't doing French Polishing... Here's a link to an article a friend of my wrote to explain the difference. French polish uses pumice, shellac and a pad; padding shellac uses shellac and a pad; both use mineral oil in the final few sessions to help the pad slide along more easily. http://www.hardwoodlumberandmore.com...g-Shellac.aspx

[Larry Fox]

I agree with Scott. This is the best article on French Polish I have seen to date. http://www.milburnguitars.com/fpbannerframes.html

[John Coloccia]

I agree with Scott. This is the best article on French Polish I have seen to date. http://www.milburnguitars.com/fpbannerframes.html

Having been "corrected" by Scott about French Polish multiple times over the years now, I'm not going to get into a silly argument about this. Suffice it to say that you don't use any pumice when you French Polish woods that don't require pore filling, like Maple and Spruce, because the only purpose of the pumice is pore filling. And if you like the article you linked to, then you agree with me, not Scott.

From the article:

We are then ready to fill the pores and grain. This is the pumicing operation. At this point we should mention that there are some species of wood that do not require grain and pore filling. The top of the guitar will not have to be grain filled. Spruce, Cedar, and Maple are examples of "closed-pore" woods which do not have to be grain filled...

And you won't get a different answer from any instrument builder on the planet.

[Eric Thumb]

Soppy wet is the forecast. Right now it's 94 degrees with 52% humidity, if it goes to 60% we have to get out scuba gear to go outside.

I did as suggested and sanded it down with some fresh 400 wet/dry and rubbed on it for a few more minutes with my shellac pad. That seemed to help level out the grain/pores tremendously. All that I can really see now are the faint scratches left by the 400. I'll probably rub on it some more to build up the shellac and sand it down again only this time with 1200 wet/dry then start on the final "coat".

My arm has not yet fallen off but I have only been working on a few smallish boxes and taking long breaks in between reading and trying to figure out what I am doing wrong. I was not exaggerating when I said that there was a post on page 210 in the finishing forums about french polishing that seemed to give me a breakthrough. I read every post and link about shellac up to that page. Then I went ahead and read until I got to the last page just because I was so close.

I appreciate the info!

[Pete McMahon]

John, Well put. I and many others use no oil in our polishing at the beginning or end. Therefore in a strict sense we are not F.P. I know some very good polishers who don't use pumice but use rottenstone. Certainly not as abrasive and much finer, but if you saw the period pieces this person does you wouldn't argue with the results. To the O.P. you'll get lot's of advice on the "only way" here. At this point you are short on experience so practice, practice, practice. Try different approaches, try a few samples with the "wrong "way. You'll learn what shellac feels like under your hand. Try and find someone with experience to help you out shorten your learning curve. It'll be fun for that person when they see you get it. Any classes in your area?

[Eric Thumb]

Unfortunately I think I am on my own with this. I called the nearest place that I knew of that I thought would offer some kind of class (Rockler in Indy, about 60 miles away) and they said that they have a guy who does classes on finishing but not French polish/padding shellac. He said that he did not know of anyone who messed with it.

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Here is what my board looks like after I sanded it down with 400 and rubbed on it some more. I've still got some lines but it looks better than it did before. If I hold the board out in front of me I can easily tell what time it is on the clock hanging on the wall behind me. It's hard to tell from this picture though. I couldn't focus on the scratches and the reflection at the same time.

So what's next? I'm guessing sand with a finer grit and go to it again until I can't see any more lines? I will try some 1200 grit this time and see how that looks if that sounds reasonable.

Thanks again!

[Scott Holmes]

You probably have enough shellac now, you need to refine the finish. Whether you want to call it French Polish or Padding shellac, sand paper is not normally needed. Sanding is taking 2 steps back, 1/2 step forward. Continue to "buff" or "polish" to increase the gloss by increasing the amount of alcohol and decrease the shellac in the rag, adding mineral oil to the surface of the rag will make the rag slide over the finish without grabbing and refine the gloss... it takes practice and patience.

[Jerry Olexa]

I agree with Scott....Sanding is defeating your purpose....Shellac does not really build up (like varnish)..Padding and varying the amount of DA used should suffice,,,Scott is correct.

[Randy Goodhew]

Your picture is what I would expect to see if you did not do grain filling and/or you did not use circular motions when padding the shellac.
If you continue to use padding with strong circular motion you will eventually acheive the flatness you desire without sanding.
Although, grain filling makes it easier.
(40+ years experience French Polishing)

[Pete McMahon]

Eric,
Under normal conditions and an experienced hand sanding may not be required. From your photo it appears you applied your shellac in one direction; going with the grain. What you are seeing is called "roping". This is the shellac piling up around the unfilled pores. Part of the F.P. process includes "pulling over" This is what Randy is describing when telling you to use a circular motion.

Removal of roping is no easy feat. Sanding will work but a word of caution; don't just sand with the grain. I'd sand with a light touch a little diagonal to the roping. This will help you work on the "hills"

Grain filling, no matter how you achieve it, is paramount to a good F. P. I give you a lot of credit for diving in without any help. You've got a lot to learn and you'll progress by making these initial mistakes. In your learning process use common sense. Even if you're not supposed to use sandpaper isn't that going to help your situation? If you tried to take this down with just alcohol I can (almost) guarantee frustration. Good luck with it.

[Eric Thumb]

I did go with the grain predominately but threw in a few swirls every now and then so what you are telling me makes sense. I am using an old cotton t-shirt with cotton gauze inside for my pad and I had thought that it may be the t-shirt material that was causing the lines. It probably is but I imagine any material would cause lines if you kept going back and forth in the same direction. I just need to find that sweet spot. Also giving my mistake a name (roping) somehow comforts me.

I will continue working on it and I feel like I am learning something. I'm also going to scour the neighborhood (or state) for anyone who knows what the heck they're doing. Any ideas on where to start looking? Museums? furniture stores?

Thanks

[Pete McMahon]

Eric,

First off get rid of the tee shirt and get something thinner. Think of and old handkerchief as far as thickness goes. A tee shirt is basically barbaric for fine work. The face of the pad has to be absolutely flat, no wrinkles. Great arguments can arise when discussing the inner core. In my opinion gauze is too soft and mushy. A good grade of cheesecloth or raw wool have more body and better working characteristics.
My sequence is circular to figure eights to straight strokes. Much of the initial application of the shellac is in the circular and figure eight stage. With a beginner I'll let them get a good surface and then pad a few circles into it. It teaches one how to remove imperfections with the pad alone.

Furniture stores would be a waste of time. Look for a restorer or finisher with experience that may be willing to give you a few tips. Offer to pay for their time. Don't be surprised if you're met with a stone wall though. You may have to hunt around for a class outside your demographics.

[Scott Holmes]

Eric, Applying mineral oil to the face of the pad will help the pad slide and not grab or leave ridges. As Pete said "tee" is not the best material for the pad. I use raw wool inside for the reservoir.