Finishing Process

[Andy Morton]

You seem to be very careful...and not apt to rush things as shown by your questions....I would say that a shellac based french polish with care and thoughtfulness (including some practice) would turn out very well for you. For me at least, it is very easy to correct any finishing mistakes or imperfections with successive applications assuming you can take the time (advantage of a hobbyist luthier) and are not on tight schedule for completion of the instrument.

Andy
Madison, WI

[Jules Tenney]

I put some tru-oil over the stain on the dummy top: yes, it is now more red, and a little darker for the tru-oil. i can leave the final finish decision until the stain is on, and yes, there's no need to rush into anything at this stage of things and mess it up.

[Jules Tenney]

Tonight question is:

The dye has raised the grain on my sample. So I will have to raise the grain with water, and sand it off before staining, right? It's supposed to be a NGR, did I put too much on? The sample is quite soft pine, and I appreciate that is not the same as the mando...

So the real question: if you have to raise the grain and sand it off, do you then proceed immedietely to staining, or can the wood sit at all?

And you clean it after sanding with what we call lighter fluid, like for a zippo?

thanks,

[sunburst]

Wet the wood to raise the grain, let it dry, re-sand just lightly enough to remove the "fuzz", and you're ready to stain. Brushing with a dust brush and/or blowing with compressed air is enough to clean the dust off. The stain and finish work best directly after sanding, but you can wait a day with no real problems.

[Jules Tenney]

what about time between applying the stain and the first coat of finish? I'd have thought there was a bit more to play with there?

[sunburst]

You can get away with longer, but sooner is better, just like a glue joint. Either way, you want something to stick to the wood (glue or finish) and a freshly prepared surface sticks best.

[walt33]

At least he didn't call you a banjo maker!

[Jules Tenney]

Tonights poser for you fans of finishing is this:

After Behlen Solar Lux Dye. A Tru-Oil sealing coat before the French Polish? Is that an acceptable way forward? I need to seal the dye before the french polish, definitly, and tru-oil will work as a sealer?

I can get some other sealer, but I was planning on doing a pure tru-oil finish: in fact it appears I have an option to take a foot on that road before finally committing to finsih the tru-oil, or switch to french polishing?

That's a good option if it stacks up.

All the hardware is off now. Plan to do the stain this weekend, with the rest of the evenings this week on the final bits and pieces.

A further question for those finishing freaks out there that found the first one too easy is this: how to keep dust away from the french polish as you do it?

[Tavy]

I use shellac all the way. IMO shellac makes a good sealer for TruOil, but I wouldn't do it the other way around - if you accidently sand through the shellac into the TruOil when levelling there's a good chance you'll end up with witness lines. Which is not to say it can't be done... most things can

The trick when applying the first shellac coat with a pad, is don't hang round, and never touch the same area twice. Follow that and you really shouldn't get any colour blead... but as ever try it out first on one of your scraps.

[Bill Snyder]

I have not used a true french polish but I have finished a few instruments by padding on straight shellac and dust has never been a problem because the straight shellac dries so quickly.

[Jules Tenney]

When you're applying he stain, how do you gt in under the fingerboard extension, and around it's support? I can imagine making a mess there. I'm guessing that I would stain the easy bits of the top, and get the pad in there as much as possible, and then get in there with a smaller brush / small pad?

Thanks for the advice on shellac over oil. I read somewhere that Gibson finished their early mandolins with Shellac over an oil finish, and have seen several other folk recommend it as a method. Any other experiences? On the other hand, if I just use a shellac wash coat, you just apply it with a soaked pad, and basically get it on as fast as possible, in lines down the mandolin, or you do the curly figure-eight french polishing motion? I think I'm becoming possesed with this whole process... I guess I just want to know exactly what I'm doing in my head before I start...

Finally, if I want to really make the figure in the maple come out, how best to do that? Before the stain, or after?

[Dick Hutchings]

You can't rub or pad shellac over stain without spreading, smudging, wrecking your stain job. I found that out the hard way on #1. You should spray some very light coats of something before padding.

[Jim Hilburn]

If your not set up to spray I noticed in the Fernandez french polish video he brushes on a sealer coat of shellac before proceeding to the pad. However he isn't sealing color since he's doing a classical guitar. I just wonder if you were to brush on a wet coat if you could get away with it. I bet you could if you used water dye.

[j. condino]

You can't rub or pad shellac over stain without spreading, smudging, wrecking your stain job. I found that out the hard way on #1. You should spray some very light coats of something before padding.

If you use a solvent based stain and then try to pad on a solvent based finish, like shellac, the colors will pull and run. (I've also made this mistake early on...) That is why you find both water based stains and solvent based from better suppliers. My preference are for the separate ones sold by LMI. If you use the water based color on the wood as shown in my video over at finewoodworking.com, you can rub it all day with shellac and there will be no color pulling or smudges. If you use one of the more generic types like colortone that claim to work in any liquid medium, you may run into different issues like color pulling and smudging. The ultra -toxic MEK color dyes can aslo be padded on by hand, but can run into issues with them smudging and running also, but the color intensity is off the charts once you find a way that works for you!

The number one thing to remember about almost all finish work is that time in the saddle usually trumps all advice. Practice, practice, practice, and then start working. When I first started french polishing and hand rubbing color sunbursts, it probably took me close to 60 hours of fussy, delicate work to get a finish that I was unsatisfied with but finally gave up and had enough with the process. Now it generally takes me one hour long session for all of the color work, another hour for any scraping and touch up, and then five 45 minute sessions complete the entire finish- that is quicker than I can do spray work and clean up all of the equipment and without any of the chemical offgassing issues. It is really more of an approach and mindset than a complex process. For folks interested, I'll be giving a full demonstration of the handrubbed sunburst at the Guild of American Luthiers show next month.

Post some images and let us see the process- we're a bunch of visual geeks...

j.
www.condino.com

[Mike Black]

Post some images and let us see the process- we're a bunch of visual geeks...

That's what I was also thinking.

James, Do you think there will be any video of your Guild demonstration for those of us that can't attend?

[Jules Tenney]

I think the problem comes down to sealing the dye. This is a one colour finish, so more forgiving. Thanks so much for bearing with my questions.

I've mixed up some shellac and tried it on the sample. It is much more what I'm after than the tru-oil, so that's what I'm going to do.

The choice I have, I think, is either switch to a water based dye, or find a way of sealing the dye stain I have before trying to apply the shellac by hand at all.

Are there aerosols of shellac sealer available? Or something else that would work?

I think brushing might work better than padding if I end up applying that first coat with my hands.

thanks again, this is so helpful.

[Mike Black]

You can try using this to spray on the first coats of Shellac.

[Tony Francis]

Jim how did you like the Fernandez dvd?

[Jules Tenney]

Now it generally takes me one hour long session for all of the color work, another hour for any scraping and touch up, and then five 45 minute sessions complete the entire finish- that is quicker than I can do spray work and clean up all of the equipment and without any of the chemical offgassing issues. www.condino.com

This is exactly what I want to do. What exactly do you do now?

On the other hand, you wouldn't do what you do now, if you hadn't gone through that initial 60 hours, and for all 60 of them I imagine you were doing what you thought was the best thing. That's where I am. Working on the samples is most illuminating.

[Jules Tenney]

You can try using this to spray on the first coats of Shellac.

I wondered about that.

I had even thought about using one of those things my mum had to water the flowers with. Sort of pump action spray gun she used to put Baby Bio in. I imagine that would end in tears... yes?

[j. condino]

Mike:

I'm pretty sure that there will be a film crew there covering the whole workshop that they will likely use in the future. As for right now, I just know the day of the event production details. It should be in one of the large halls at Pacific Lutheran University where I'll be wired for sound and they have a film crew doing closeups of the details while I work that will be projected on one or possibly multiple large screens; kind of like having a fancy gig with a nice band at one of the festivals where they project everything so the folks in the cheap seats can see a little!

We're also in the process of finishing up a spray finishing video that Ken Jones and I did with the film crew from Dream Guitars in the booth with us. You'll be able to see a full sunburst on one of Ken's guitars, a historic uke, and and a GIANT 'burst on one of my double basses that mimics the Brock '59 Les Paul. That one should be up on their Youtube channel soon.

The best thing I ever did for my learning curve with French polishing shellac was to take a private workshop from Eugene Clark- the old classical guitar Jedi- about a dozen years ago. He channels everything down to just what is important and throws away anything that is not. His results are very fast, timelessly beautiful, and his methodology is near zen like....as he told me, "Why would I ever need to take up yoga or fly fishing when I get to blissfully French polish my guitars every day....."

j.

[Jules Tenney]

OK, this is the answer for the first coat of shellac:

http://www.behlen.co.uk/Merchant2/me...Category_Code=

Zinsser Spray Shellac. Any tips on using that?

[Jim Hilburn]

Spray light. Don't try to get a thick build all at once.

[Jules Tenney]

Spray light. Don't try to get a thick build all at once.

I plan on spraying several light coats until I feel confident it's all sealed, especially around the bindings, and practicing first. I expect to just let a fine mist come down over it a few times, a few seconds each time, but practice will tell me how quickly it sprays.

I'm stunned at what shellac has done to the sample I stained, it almost glows, and the wood has really come alive.

[Jules Tenney]

Tonights dilemna for you finishing fastidiards is this:

Mask the bindings or not?

I can see pros and cons either way. Putting the masking on seems very tedious. Scraping the bindings also seems very tedious.

Nearly ready to go with the stain now...