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ed mirzay
02-02-2010, 8:46 PM
I'm attempting to finish a bubinga/maple desk with shellac over the already applied oil. :rolleyes:

On my test pieces I am having an impossible time finding a happy medium between applying the shellac and leaving little ridges and sanding out the ridges (with 600 grit wet/dry lubed with mineral spirits).:(

I've got the shellac down to a 1/2 lb cut...started with a 2 lb and after battling ridges thought if I diluted they'd go away but they don't.

I've tried both brushing (airplane smooth landing/takeoff technique) and padding (cotton cloth with shellac soaked cheesecloth inside, apply only to the cheesecloth). I reload either as soon as I feel the slightest stickiness.

After applying the shellac I've tried going back over it with an alcohol soaked cloth to work out the ridges but I can't seem to do with without leaving a very dull area that appears void of shellac (the alcohol soaked cloth/pad show signs of collecting the shellac).:mad:

I love this finish, in theory, the wood looks fantastic in the smooth areas, but what I am doing wrong?:confused: Any help is appreciated. Thanks!!!:D

Steve Vaughan
02-02-2010, 10:35 PM
Ed, I feel your pain cause I can't do squat with brushing shellac, after many attempts. I will say that I have brushed it on smaller projects, and once dry completely, have been able to sand it out smooth. My problems seems to have been associated with either old shellac that wouldn't cure completely or I was using the wrong sandpaper so it would always end up clogging. Maybe that could be part of the issue. Hope it helps a little.

Prashun Patel
02-02-2010, 10:53 PM
I'd stick with it. You will eventually develop a good touch and sense for this.

Your risk now is putting on too much shellac; that will make the ridges hard to dissolve and smooth out.

With a 1/2# cut, you're risk of moving too much shellac out of the area when blending is high. To blend ridges, I find it easier to do it in steps:

1) Gently massage the ridge in widening concentric circles until it's smooth. Let dry. Forget about what this does to the sheen.

2) After dry, load with shellac and either swipe over the dull areas.

You will find that after a few coats, the sheen evens out.

Keep it light; don't work it too much; be willing to wait between coats and don't try to get it all even on one coat.

Scott Holmes
02-03-2010, 12:35 AM
A couple of comments... you may have missed in the airplane take off and landing approach...

That is the padding method, not the brushing technique. Brushing you flow it on; DO NOT GO BACK. Padding you use a touchdown, pad, etc...

To get the DNA dampened pad to smooth the shellac you need to lubricate the pad with mineral OIL (not spirits). That is the proper padding technique.

Neal Clayton
02-03-2010, 2:11 AM
for brushing, i use a plain ole purdy china bristle brush, a large one, i don't like running out mid stroke (about 3" or so).

and don't get mad at me ed if you do know how to use a brush and this is preaching to the choir, but i think alot of people don't know how to properly use a brush. i've seen it when watching people try to learn to paint with a brush quite often. i'm using "you" as a general term, not specifically at you.

you can't dab it on, putting less finish in the brush only at the bottom doesn't result in a lighter coat, it results in a runny coat that only has enough finish to be runny in one spot. you need a consistent flow as scott eluded to, get more in the brush, not less. saturate the brush, all the way up near the hilt. then let the excess drip out, knock the hilt a couple of times against the can to get the last couple of drops that are about to fall, and you're ready to brush it on. even pressure is all you need from then on. if you get too much in the bottom of the brush (half dipping it) it's gonna run. if you get too little in the brush, you're gonna run out before a single stroke and have to overlap what you did before. as you empty the bottom of the properly saturated brush, more shellac runs down from the hilt until you run out, and your flow should be consistent.

rules of simple gravity apply, don't try to defeat the design of the paintbrush, it has worked that way for thousands of years and won't change just because someone wants to try it different ;).

Scott Holmes
02-03-2010, 7:43 PM
To add another tip to Neal's proper brushing technique...

PRE CONDITION your brush not the wood (as in pre-stain conditioners)

Dip the bush in the proper thinner for the finish you are using DNA for shellac and mineral spirits for varnish.

This will fill the brush inside the ferrule (Neal called it Hilt) so while you are using the brush the finish will not get up in the ferrule and harden. This is VERY important when using varnish; when it's time to clean the brush there is not finish up in the ferrule. Makes cleaning very easy.

I have a varnish brush that has been used and cleaned 200+ times. Many people have seen it and thought it was NEW.

ed mirzay
02-03-2010, 8:47 PM
Thanks for all the advice. I'll have another go and report back.

I did lube the pad with mineral oil by putting a drop on it and rubbing it around. Was afraid to use too much.

Kent A Bathurst
02-03-2010, 9:41 PM
.......I've got the shellac down to a 1/2 lb cut..... and padding (cotton cloth with shellac soaked cheesecloth inside, apply only to the cheesecloth). I reload either as soon as I feel the
slightest stickiness.

A few thoughts:
1. 1/2# might well be working against you - virtually all DA, which is flashing off instantly. I always am around the 1.5# range.
2. Others here might disagree with this, but I think a wetting agent helps. I use Behlen Laquer Retarder at 8% - 10% by volume. There is also something called "shellac-wet" at Homestead, but I haven't tried that one. The purpose is to retard the cure and keep a wet edge longer for the next swipe path
3. If you reload when you feel the slightest stickiness, I think you are too late. That means it is curing, and you'll drag into the previous stroke.
4. IMO it's too difficult and too time consuming to do a good job with DA to try to level it out. That ship sailed. It's down, it's done.
5. I use padding extensively, but not with a french polish pad, which is what you've got. I use padding cloth - bascially lint-free cheesecloth-looking stuff. Used to get it a Homestead, but they've gone to a different product which I'm sure is good. Highland also sells them (I think they call them finishing cloths, though). Works VERY well.
> Load pad with 1/2 - 1 oz DA, light squeeze to distribute it evenly through the pad, then squirt shellac out of a squirt bottle.
> Airplane-style landing at 1" in from the edge, off the other edge, same motion returning on the exact same path, then move over with a 1/4" or so overlap.
> Cloth in one hand, shellac squirt bottle in the other - reload very often (but I quickly turn away or duck hands below the bench so those annoying splatters don't hit the work piece).
> I'll put on 4-5 coats back-to-back, wait an hour, very lightly scuff sand with 3M 600 gold, one or two more light coats.
> I have to focus on moving a bit slower across the surface than I seem to want to - not casual, but at a reasonable speed that will let the shellac flow out of the pad - high speed with the pad doesn't work. By the same token, there isn't time to screw around and keep the wet edge either.

Took me a while to get the hang of it, of course, but this stuff is "knowable" and didn't really take that long. Cork pad with the 600g removed a lot of "learning" shellac at the beginning, but that's OK - the film builds right back up as long as you don't cut through to the wood. I am contemplating another run at brushing, which wasn't working for me at all in the beginning.

Mike Shields
02-04-2010, 3:02 PM
I'm attempting to finish a bubinga/maple desk with shellac over the already applied oil. :rolleyes:

On my test pieces I am having an impossible time finding a happy medium between applying the shellac and leaving little ridges and sanding out the ridges (with 600 grit wet/dry lubed with mineral spirits).:(

I've got the shellac down to a 1/2 lb cut...started with a 2 lb and after battling ridges thought if I diluted they'd go away but they don't.

I've tried both brushing (airplane smooth landing/takeoff technique) and padding (cotton cloth with shellac soaked cheesecloth inside, apply only to the cheesecloth). I reload either as soon as I feel the slightest stickiness.

After applying the shellac I've tried going back over it with an alcohol soaked cloth to work out the ridges but I can't seem to do with without leaving a very dull area that appears void of shellac (the alcohol soaked cloth/pad show signs of collecting the shellac).:mad:

I love this finish, in theory, the wood looks fantastic in the smooth areas, but what I am doing wrong?:confused: Any help is appreciated. Thanks!!!:D

I feel your pain. I've spent considerable time not only working with shellac, but also reading up on the subject, but have yet to get it right.

I've gone thru about 16 ozs of shellac. I've tried brushing, then padding, and now back to brushing. I trashed about 10 sheets of sandpaper getting rid of all the mistakes.

I attempted to dilute to less than 1#, thinking that high altitude dry air was hindering my progress. Analyzing everything I've done so far, it's my lack of experience that is causing me to produce constant ridges, as you described.

If I could only brush each pass just once, I think that is critical. If there is any ridges after a single coat (with no overlapping), sand back until the surface is smooth of ridges. This is after it has dried. Then do the next coat, never overlapping the brush strokes, as this is what is causing my ridges.

Very time consuming, but in the end, this shellac is incredible!

I'm picking up pumice and rottenstone today. My goal is to have several coats applied, and only ridges on the last coat. I'll then use the pumice and rottenstone to "finish the finish".

Don't know if this is the correct approach, but I'll try it as I've spent one week with so many other attempts, and they've all failed.

Good luck. I'll be watching this post to see if any other good ideas pop up.

Neal Clayton
02-04-2010, 7:29 PM
i think you guys may be getting it too thin, and exacerbating your problems.

i brush with a 2 pound cut. never many issues. at that consistency it's just heavy enough to hang on vertical surfaces without running.

Doug Hobkirk
02-05-2010, 11:19 AM
Kent - I want to improve my shellac skills, so maybe you could clarify a couple of points.



...
5. I use padding extensively, but not with a french polish pad, which is what you've got. I use padding cloth - bascially lint-free cheesecloth-looking stuff. Used to get it a Homestead, but they've gone to a different product which I'm sure is good. Highland also sells them (I think they call them finishing cloths, though). Works VERY well.



In your opinion, would a 12"x12" piece of old t-shirt or sheet work as well, assuming I folded it so the cut edge didn't touch the surface being padded?
Do you store your pad in a jar and reuse it?




...
> Airplane-style landing at 1" in from the edge, off the other edge, same motion returning on the exact same path, then move over with a 1/4" or so overlap. ...


I think I understand the airplane landing so you avoid the blob that occurs on the edge. Do you lift off before the back edge or run flat to the back and clean up the excess that drips down?




...
> I'll put on 4-5 coats back-to-back, wait an hour, very lightly scuff sand with 3M 600 gold, one or two more light coats.


Now I am stumped. "4-5 coats back to back"?


Thanks

ed mirzay
02-08-2010, 11:39 PM
OK, I think I have this stuff figured out on the maple but its the open pores on the bubinga that are giving me fits...though I have a plan of attack.

I intend to build up the shellac via additional layers to fill in the pores but attempt to not build it up so much that it becomes a very thick finish.

Advice for tackling open pored wood? I have this mental image of the shellac falling into the pores, eventually I will have them plugged.

Scott Holmes
02-09-2010, 12:48 AM
I use super blonde de-waxed shellac as a filler for open pore woods all the time.

Use a 2 or 3 pound cut and brush on 2 or 3 coats; waiting for it to dry between coats... say 30 minutes or so.. Then, sand or better yet use a cabinet or hand scraper to remove the shellac back to level. Now the pores are filled with a hard, colorfast, optically clear filler that adds incredible depth. NOW top coat.

Hans Braul
02-09-2010, 9:45 PM
Interesting post - I can identify. One question: the take-off and landing technique works great on a big flat surface, but how do you work around corners and irregularities on finished pieces? I tend to pre-finish pieces prior to gluing for this reason, but I think I'm in a small minority here.

Regards
Hans

Dan O'Sullivan
04-25-2010, 6:40 PM
Scott
I use your approach now and I have done this over the years with good results. Lately, after reading a blurb by a finisher that used to write in FWW(woman out in NM)about sprinkling rottenstone on the wet shellac surface and filling the grain with shellac and rottenstone. When it dries she goes back and polishes it out with a mineral spirit and mineral oil lubricant and 600 or so paper. It gets smooth but dull. I am using this technique now.

To finish it out, I polish this with some thin shellac/buttonlac and its impressive. After all.. the base is what its about and when its dead flat the shellac just lays down and shines. This is an easy filler method. If it gets caked up or thick a wet DA rag takes it off quickly and you're ready to start again. Another case for shellac I guess.
dan

Neal Clayton
04-25-2010, 10:30 PM
if you think about it, with all of the finishing products available, how many can do what shellac does?

sealer, color, grain filler, top coat, barrier coat.

it's still available everywhere because it's so useful.

Scott Holmes
04-25-2010, 11:15 PM
And the reason not everyone sells thier own "brand" of shellac...

You can't patent a natural product.

Neal Clayton
04-26-2010, 4:40 PM
Interesting post - I can identify. One question: the take-off and landing technique works great on a big flat surface, but how do you work around corners and irregularities on finished pieces? I tend to pre-finish pieces prior to gluing for this reason, but I think I'm in a small minority here.

Regards
Hans

try to organize your brushing in such a way that you get to those parts when the brush is almost empty, so that you don't accidentally press out too much and cause a run.

Howard Acheson
04-26-2010, 6:54 PM
The thinner the cut, the faster the alcohol will evaporate and the less time the shellac has to flow out. 1 1/2 - 2# cut works best for brushing.

Scott Holmes
04-26-2010, 11:55 PM
Dan. I missed you reply...

You are essentially using a modified "french polish" technique. There are more effective ways to do a french polish.

French polish technique is indeed an absolutely beautiful finish, if done properly. It is very labor intense and definitely OLD SCHOOL.

Jim Barry
04-30-2010, 11:27 PM
I read an article in Fine Woodworking a few years ago, I think it was by Jeff Jewitt, that you can retard the drying time of shellac with the addition of a little turpentine to the mix. If memory serves it was 10 to 15%. I've tried it and it does work and as a bonus, your shop will smell like a Christmas tree.

Jerry Olexa
05-01-2010, 12:26 PM
After applying the shellac I've tried going back over it with an alcohol soaked cloth to work out the ridges but I can't seem to do with without leaving a very dull area that appears void of shellac (the alcohol soaked cloth/pad show signs of collecting the shellac).:mad:

Ed, This is common when padding the shellac. I find using a circular motion with your pad gradually eliminates the dull area. The trick is to keep increasing the amount of DA on your pad each application along with the shellac and a drop of oil . it will eventually "blend" and the dull area will go away. Think of it as "redristributing" the shellac evenlly over the surface. It works. I only brush the first coat, pad all after that and I never sand. HTH...