All,
I usually struggle through appling shellac and usually get farily lucky with the outcome. This time, however, I’d like to eliminate some of the guessing and turn it into knowledge…if possible.
I’m finishing a small cabinet that measures 14.5×20.5x 28″ tall. It’s made from maple with a drawer and storage area ..Shaker style. The construction is frame and panel (including doors, that makes 6 panels).
I sanded to 150 and padded 6 coats of 1.2-2.0 lb. garnet shellac. The first four coats were applied straight like an airplane…the last two coats in figure 8’s..in politician style(ha, ha).
Anyhow, as I stand back and take a long look I see a very smooth surface.. …however the color is somewhat mottled (mottledz= different shades of shellac next to each other). Also, in a few places, I see where a thin dark stripe of shellac has formed…usually near a verticle upright.
Any suggestuons for how to remove mottling and the thin dark lines of shellac? thanks
Replies
I have never understood how anybody can apply more than two coats of shellac and I have used commercial stuff and rehydrated flakes. The subsequent coats always melt the previous coats and that causes a mess, at least for me. (If there's a trick I would love to know it.) I only use shellac for a sealer, for example over water based analine dyes if I am (rarely) going to use a water based finish.
But I love shellac for bringing out the beautiful details of spalted curly maple.
John
The Taklon Gold watercolor wash brushes work well in part because they are almost the exact opposite of a good varnish brush. The fine bristles and the construction means there is not a large reservoir so that only thin layers are deposited. These dry fast--usually too fast to do more than melt into lower coats, not reliquify them.
The second part is that you have only one chance on each coat to place the shellac. Brush strokes are one way only, and overlap as little as possible. A skip is just skipped and picked up next coat, not with back brushing.
You also have to increase the drying time between coats the more coats are on the surface. If the second coat can go on 15 minutes after the first, the next should wait 25 minutes, and the third 45 minutes. And if you do start to feel the drag that indicates you are picking up lower coats--just stop immediately. Don't even complete the stroke, just lift the brush or pad. Let things dry more completely and can continue a bit later.
Pins,
I've had similar issues with shellac, that is why I'm asking the question. There are a cazillion pieces out there with a shellac finish that look beautiful...I'm thinking, unless global warming is the issue, there's gotta be a way.
BG, So far I've gotten some good advice in this thread and I rally like fast drying finishes but spraying lacquer and shellac requires a little too much clean up for me. Actually spraying anything but water based is too much clean up for me and I have both HI and LOW systems but both are not very fancy.John
Its true spray equipment used for waterborne is easy to clean--unless something happens that delays the cleaning. Once the finish cures you have a much harder cleaning problem. Shellac (or lacquer) can always be dissolved with the appropriate solvent.
What you are seeing is varying film thicknesses of the shellac. The thicker the film, the darker the amber color will be. Short of being able to lay on a perfectly consistant film, you will have the varying intensity of color. Not too much you can do about it. The more layers you apply the more the differences will be apparent.
Working with shellac takes practise and experience.
There are several things you can do at this point. I think the easiest is to do a bit of sanding. Use a sanding block. That can remove some of the worst of the variations and remove enough of the shellac that you can add more without getting the overall color too dark.
You can also work the surface with alcohol or a very thin cut of shellac to rewet and "move around" the shellac to even out the color. It can work--though it can also lead to an awful mess. Stop immediately if you feel the shellac "rumpleing" under your pad.
You may have been overly systematic with your application, or not systematic enough. You don't want each stroke with brush or pad to be in the same place you want enough variation that if one stroke overlaps another those overlaps don't occur in the same place on each coat. Working with thin cuts while padding--1 lb. is good, gives more opportunities to "average out" the skips and overlaps. You are now aware of what happens when each padding stroke ends at the same place near a vertical.
Steve,
I made a new rubber yeaterday where the inards were dampended with alcohol and wrapped a block with 400 grit with the intention of correcting the issues. I also thinned the sqirt bottle a bit. I've leveled aggresively before(other project) using the 400 grit and a sprinkle of water...but that was to achieve a smooth surface...it's not clear how far I'll have to go to achieve color evenness. The surface is quite smooth and the top is perfect. If this were mahogany or a stained piece I suspect the color variation would not be detectable. That's a great tip about waiting a bit longer as the number of applications increases. thanks
BG,
I agree with Steve's sanding advice. Let the present shellac coat dry completely. Use a rubber or felt block with 220-320 grit. When you sand, if you don't get the driest, fine powder, stop immediately and give the shallac another day or so.
When it's really hard, sand gently, but completely, aiming for a uniform dull appearance. You may have to cut through this existing coat in places, barely down to the wood, as it's usually not possible to uniformly sand a first coat finish. I never try to get anything but the highest "hills" of finish abraded at such an early stage. But you are sanding now for a different purpose than ordinary scuff sanding.
The idea is to get as much uniformity by sanding as possible. Don't try to even things up by padding/rubbing with alcohol. You'll hate the results even more.
After sanding, follow the advice already given on brushing. But if you have spray equipment, I really recommend using it. I never brush shellac, and now you know why, and I use only very bleached varieties. Shellac is one of the easiest finishes to spray. The least expensive equipment is all you need. Even the stuff in spray cans is fine. Lap marks are non-existent. Runs and drips are less of a problem than when brushing.
Many very light coats are the way to apply shellac. Shoot several light coats (2-3), several hours apart, let completely dry for a day or so, scuff sand, another course of spraying, etc. Build the finish as necessary, and never worry about mechanically moving the previous layers.
Rich
Rich14,
" Don't try to even things up by padding/rubbing with alcohol. You'll hate the results even more." Yup, in the past I have...and hated the results. I don't really understand why it won't work.
I'm not affraid to sand but I'd like to be more confident that the re-appliation will work..perhaps spraying is the only way given this is unstained maple with a lot of natural color variation...a bit of tiger stripe and a few birdseye here and there...
When one attempts to use garnet or dark garnet shellac on a light colored piece it is really the same as applying a toned top coat. It has enough color to effect the overall color and is therefore very much like applying a toned lacquer. This is going to be tough to get right using a padding application. I think spraying is the way to go with this material. It will take some practice to learn to achieve a consistent application, however you will have the option to crosshatch your application in order to achieve a more consistent color. As far as cleanup goes I find it easier to clean shellac out of a spray gun than waterborne products. I just throw a bit of lacquer thinner in the gun after it is dumped out and let it sit for awhile. I then take apart the gun and put the parts in more lacquer thinner for the final cleaning. The gun cleaning takes less time than trying to fix an unsatisfactory finish.Spraying will also allow you to apply more finish in less time than padding so the cleanup time really becomes a small issue.RonEdited 7/5/2006 8:34 am ET by Ronaway
Edited 7/5/2006 8:34 am ET by Ronaway
Ron, my spray experience is minimal and not with shellac, so I have a newbie question about your cleaning recommendation: Why does lacquer thinner work with shellac?? Would not simple denatured alcohol work? Or does it not work as well as lacquer thinner?? Thanks in advance!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
FGLacquer thinner works much quicker than denatured alcohol, although a mixture of the two would also work. There is also a stripper/cleaner that I buy from Jeff at Homestead that also works on shellac even though I initially bought it to clean waterborne finishes from my spray guns. The lacquer thinner is much more readily available.Ron
Ron,
I've never used anything but alcohol to clean shellac out of a gun. No problem at all. Why use anything more toxic, or polluting?
Rich
Rich it is not unusual for me to be spraying off and on all day and well into the night. At that time of day I want the solvent that gets the gun clean and gets me out of the shop in the shortest amount of time. I am in my shop 5 to 6 days a week all day long (and sometimes into the night) if I wasn't putting in those kind of hours I would probably use the alcohol and I am sure it would work just as well.Ron
Ron,I think the lacquer thinner is cleaning the gun because there is already alcohol in there, or your brand of lacquer thinner has a high proportion of alcohols.Shellac doesn't disolve very well in most lacquer thinners at all. (Lacquer thinners - there isn't just one - are mixtures of various hydrocarbons including toluene, ketones, acetones, ethers, acetates, evaporation inhibitors, and a little alcohol - the percentages are proprietary information of each manufacturer)Drop a few shellac flakes in a jar with a few ounces of thinner and tell me how much of the flakes remain the next day. I think you'll find that pretty much all of the flakes are still there. In alcohol, they're in solution by then.In fact, a common practice of refinishers to determine the type of finish they are restoring is to try various solvents. If the finish softens or disolves with lacquer thinner it's lacquer, if it doesn't, it's shellac or varnish. Next test with alcohol, if it disolves, it's shellac, if it doesn't, it's varnish.
While not the best solvent, lacquer thinner will pretty consistently dissolve shellac. Therefore the test for finishes must be done in reverse order--first test for shellac using alcohol (which may soften lacquer but not readily dissolve it) and then test for lacquer using lacquer thinner. Lacquer thinner may dissolve waterborne finishes too. If you know the finish has been applied recently you may need to test whether it is lacquer or waterborne by using toluene, which won't dissolve lacquer, but will affect waterborne.
Steve,Lacquer is much more resistant to alcohol than readily softening in it. So either way, test with alcohol first, or lacquer thinner first, it becomes apparent with which of the 3 classifications of finish one is dealing.But try some shellac flakes in a jar of lacquer thinner to determine how effective lacquer thinner is as a cleaner of that finish.
"...toluene... ...won't dissolve lacquer, but will affect waterborne."
Hi Steve,
Put of curiosity, have you noticed whether Briwax containing toluene has any effect on waterborne finishes?
-Jazzdogg-
"Don't ask yourself what the world needs. Ask yourself what makes you come alive, and go do that, because what the world needs is people who have come alive." Gil Bailie
I haven't tried it. Probably the solvent evaporates so rapidly that it doesn't have much time to do damage, but in my mind Briwax is mostly for old finishes that need cleaning along with the wax, not for new work. There are lots and lots of waxes most of which would be perfectly safe for fully cured waterborne finishes, so why take risk.
Hi Steve,
Personally, I don't use Briwax because I see no need to expose myself to toluene unnecessarily.
I guess you could say I'm vicariously curious because I come in contact with several hundred burgeoning and experienced woodworkers at school every semester, some of whom seem to be quite keen on using Briwax.
Thanks for the feedback,-Jazzdogg-
"Don't ask yourself what the world needs. Ask yourself what makes you come alive, and go do that, because what the world needs is people who have come alive." Gil Bailie
The wonders of marketing. Briwax certainly appears to do it well.
"...toluene... ...won't dissolve lacquer, but will affect waterborne." Speaking of toluene, I use Behr's Clear Lac a lot and toluene is one of its primary solvents so I always left the brush soaking in it between applications, rather than clean the brush each time. I leave other brushes, sanding sealer or varnish, soaking in mineral spirits.The toluene brushes always come out clean and soft, the mineral spirits brushes are not clean and get build up. (Speaking here of releative clean)So I decided to soak all brushes in toluene and they are much better. I just shake off the extra solvent and whack them back and forth on a 'cleaning post' to knock off additional solvent and any residue and they work fine and it saves a me lot of time.Its a keeper for me.John
I hope you are doing the toluene in a VERY well ventilated area.
I believe there are now 2 Briwaxes--one with toluene and one without. If you use the toluene containing one on a varnish finish that is not completely cured, you may have trouble.Gretchen
Gretchen, As to the ventilation, when the weather is mild my doors are open, when hot I use fans.I don't understand the second part of your post. I use the brushes to apply fresh coats of finish and toluene is just another solvent albiet different from mineral spirits and, as I said, before I use the brush it is virtually dry, drier in fact than when I use minspirits. The small residue of toluene has no effect on the finishes at all.John
The second part was addressing some other post about Briwax and toluene--not your brushes. However, they did get dry from evaporation which leads to the next paragraph.
Toluene is a notable brain cell killer. It is truly a danger to your health. I was helping our children refurbish some antiques in their shop using Briwax. At the end of the day I had a headache like few I have ever experienced. That may seem anecdotal but I later discovered the makeup of Briwax.Gretchen
Hi John,
You may want to obtain the MSDS for toluene before you expose yourself to too much more of it. At the very least, glove up, and wear a suitable respirator.
-Jazzdogg-
"Don't ask yourself what the world needs. Ask yourself what makes you come alive, and go do that, because what the world needs is people who have come alive." Gil Bailie
Thanks, I just googled the MSDS and OSHA rates it 'moderate,' 2 on a scale of 4. I keep it a 13oz coffee can with a brush-handle size hole in the plastic top. The only exposure I ususally get is when I open the can to take the brush out and get a little whif of the 'aroma.'But as fate would have it about an hour ago I lost a very small brass hinge and while looking for it I knocked the *&%#@ can off the table behind my bench and spilled it, about 8oz, on the floor and the 'aroma' was overwhelming. So I got a load of shavings from the planer, soaked it up and disposed of it, opened the doors and turned up the fans. The smell disapated in about 30 minutes but I kept my between the stuff and the fans.It seems from several articles I read that the primary concern is that people, probably kids, inhale the stuff to get high.John
Your last statement is a bit anecdotal also. A lot of kids fry their brains with various things. You are using it often--it is cumulative. You are not getting "high" but you can be damaging your body--read "brain". This was all just a word to you for a heads up. I don't know your age, but you may want to rethink if a danger of 50% (2 out of 4), as being worth it. I'm not saying don't use it--just use some care. I have talked to furniture dealers who quit the stripping "game" because of the hazards of the chemicals.Gretchen
I believe you are misinformed about most of your points. Here is a link you may find interesting.
http://www.atsdr.cdc.gov/tfacts56.html
A little further research will tell you his point about kids was not anecdotal.
People who think stripping furniture for commercial purposes is a "game" are not proffesionals and should not have been doing it in the first place if they were unable or unwilling to do it properly.
You do no one a service by misinforming them.
Since the house is on fire let us warm ourselves. ~Italian Proverb
I did not say that kids don't get high on toluene--or other solvents. I did say they fry their brains in a lot of ways.
Use of the word "game" in the context was of a "business". It is a pretty well known use and this particular person is a professional.
I do not believe I have misinformed anyone. As I said, I am only pointing out the possibility of damage from long use of this solvent. You are completely free to do exactly what you want.
And here is a quote about the hazards to brain tissue. I was alerted to this originally by a neurologist--my husband.
Toluene enters your body when it evaporates into the air you breathe. Toluene can also be absorbed through your skin, especially with lengthy skin contact.
Overexposure to toluene mainly affects the central nervous system (the brain), causing headache, nausea, dizziness, clumsiness, drowsiness, and other effects like those of drunkenness. Other symptoms can also occur, as described below.
Nervous System: Toluene, like most organic solvents, can affect your brain the same way drinking alcohol does. Drinking alcohol within a few hours of exposure increases these effects and makes them last longer, because the effects of alcohol and other organic solvents on the brain add together. The symptoms of short-term overexposure usually clear up within hours after exposure stops. Effects occur more quickly and become more noticeable and serious as the level and time of exposure increase. These symptoms can increase your chances of having accidents.
Most experts believe that repeated, frequent overexposure to organic solvents over months or years can have long-lasting and possibly permanent effects on the nervous system. The symptoms of these long-term effects include fatigue, sleeplessness, poor coordination, difficulty in concentrating, loss of short-term memory, and personality changes such as depression, anxiety, and irritability. We do not know at what exposure levels these effects occur, and the effects have not been studied in workers exposed only to tolueneGretchen
You said his reference to kids and toulene was anecdotal. The studies I looked at disagree and were on the basis of blood and tissue analysis.
Toulene is not cumulative in animals or humans. As per the CDC document I linked to.
What was the source of your quote?
As far as your "professional " refinisher:
"characterized by or conforming to the technical or ethical standards of a profession"
I dare say the hazards of long term chemical exposure and the means for mitigating them have most likely been known far longer than they have been in business.
I stand by my observation.
Since the house is on fire let us warm ourselves. ~Italian Proverb
Edited 7/24/2006 5:24 pm by dgreen
Goodness, don't like to be informed on any other possible ideas. It's hard to learn that way.
According to my quote, it may be cumulative.
I don't believe I could make that quote up. It's even from your part of the country.
Your reference to my finisher is obtuse at best. You changed from criticizing my choice of language to criticizing his knowledge of finishing. Mr. Rogers says, Can you say "red herring". Yes, he stopped because of the hazards of finishing.
http://www.dhs.ca.gov/ohb/HESIS/toluene.htm#HOW%20TOLUENE%20ENTERS%20AND%20AFFECTS
I guess standing by your observation means you are fine with inhaling toluene. Have at it , 'm man.
Gretchen
Thanks for the source of the quote although I don't consider the land of fruits and nuts to be "my part of the country".
Cumulative is usually taken to mean builds up in the tissues. Cutting off a portion of ones body with a knife will result in the body growing smaller however the results are not cumulative ie: taking a quarter inch slice every time will not result in losing a half inch of material from the next quarter inch slice.
I was not criticizing your choice of language, I thought was very appropo, I was criticizing their lack of proffesionalism in not using useful chemicals properly. No red hering there. I am not advocating inhaling any chemical, however dire warning about killing brain cells from what you must admit is minimal exposure and false information about it being cumulative in the body is worse than useless.
Since the house is on fire let us warm ourselves. ~Italian Proverb
It may not be "your part of the country" but it is a medical assessment--rather than a manufacturing assessment.
I was not criticizing your choice of language, I thought was very appropo, I was criticizing their lack of proffesionalism in not using useful chemicals properly.
Really.
Cumulative is usually taken to mean builds up in the tissues. Cutting off a portion of ones body with a knife will result in the body growing smaller however the results are not cumulative ie: taking a quarter inch slice every time will not result in losing a half inch of material from the next quarter inch slice
Really.
And you conveniently decided to not comment on a doctor's advice not to inhale toluene on a regular basis.
what you must admit is minimal exposure and false information about it being cumulative in the body is worse than useless.
What if it is regular and not minimal because NO ONE said ANYthing. And no, I don't have to admit it is minimal exposure because it isn't ME.
Gretchen
You are a moron,
Really
Really
Really
Really
I see you have learned one word
Really
Really
Really
CDC is not relevant.
Really
He said it was in a mostly closed container untill he spilled it accidentally.
Really
You are a moron
Really
You should stick to finishing which you may know something about, and stay out of things which you obviously know nothing about.
Really
Really
Since the house is on fire let us warm ourselves. ~Italian Proverb
Edited 7/25/2006 12:27 am by dgreen
Hey buddy,
Better step back and take a deep breath. You are only a step away from nyaa, nyaa, nyaa, nyaa, boo-boo. Just a suggestion.
Count to 10,
Ray
Im counting! It was starting to get deeper than my boots.
Since the house is on fire let us warm ourselves. ~Italian Proverb
When in the Armed Forces we used a lot of chemicals for stripping, cleaning etc on aircraft. Not "Knowing" the hazards and using "commercial" strength toluene, and others without safety equipment has seriously effected my health forever. So while we all now take precautions, because we have learned of the effects over time, please be careful. It does affect your health, I have been unable to work for 5 years, and my nervous system is all screwed up. Please, just use wisely and with all appropriate precautions.
What stripper did you use that contained toulene?
What years were you in and what branch?
What rating and what did you do with these solvents?
I was in the military myself and know many others who were also.
Have you ever used alcohol (ethanol)?
How long have you been using gasoline?
Have you been around anyone who used nail polish or nail polish remover?
Have you always used gloves and or respirator when using these chemicals?
More info please.
Since the house is on fire let us warm ourselves. ~Italian Proverb
Edited 7/25/2006 1:17 am by dgreen
Edited 7/25/2006 1:36 am by dgreen
I was in the Air Force for 20+ years. I do not remember the names of all the strippers, I could go back through my VA files and get some of them, they investigated the chemicals that were in use then. They mentioned MEK, Toluene, and a couple of others. We used them to clean aircraft parts, strip paint off of wood and metal and others to clean electronic components. I was in aircraft maintenance (automatic flight controls, instruments and crew chief on cargo and special operations aircraft). When I was in there were no safety precautions for using the stuff. We did not have gloves, respirators etc. Other issues contributed to my disability, not just chemicals, but thy play an important part. Everything can be dangerous, a little care and a basic knowledge of what you are doing and handling goes a long way. I don't blame anyone, and the service changed to less hazardous chemicals.
My only intention in bringing this up was to have people be aware of what they are using, take the appropriate precautions/actions so that the love of woodworking and creating remains the main focus and joy!
When I was in the Navy 30 years ago we used probably the same stuff, there were safety sheets that told what protective gear to use and if we had bothered we could have gone to supply and gotten the gear. Of course we never did. I guess my point is that many of the things we use every day are as harmful or more harmful than the chemicals commonly used in woodworking and that with common sense and due diligence can be used safely and effectively.
Since the house is on fire let us warm ourselves. ~Italian Proverb
You put what I was trying to say a lot more succinctly. I agree with you 100% on that. Unfortunately for us the "paperwork" was not available, that said, I probably would have been like everybody else and not gotten it either.
Are you the dgreen in the AAFW club?
Must be another dgreen. Whats AAFW?
Since the house is on fire let us warm ourselves. ~Italian Proverb
Arizona Association of Fine Woodworkers
Waaaay to hot for me. I was down in Phoenix two years ago in July for my sisters wedding. Wow. The open time on your glue must be measured in seconds!
Since the house is on fire let us warm ourselves. ~Italian Proverb
Sometimes it feels like nano-seconds, and it also gives me problems because of the humidity (or lack thereof) and wood movement as well as stains and paints drying before you get the brush from the can to the board.
Do you use retarders in your finishes? I was in Chandler in the spring a few years ago, it was too hot for me even in March. Don't know how you folks do it. Northern part of your state is sure pretty though.
Since the house is on fire let us warm ourselves. ~Italian Proverb
I have not used any retarders, in fact I did not know any where available, any recommendations on brands or hints on use? I am just getting back into woodworking after a long break as the doctors have just about got me to where I can spend 2-3 hours woodworking every other day or so. After my operation next week I hope to be able to do this 2-3 hours a day.
I've tried pure turp as a retarder for shellac - works.
Regard it as just as desirable to build a chicken house as to build a cathedral. Frank Lloyd Wright
Edited 7/26/2006 8:14 am by Rennie
What other strength toulene is there and what was it adulterated with? What other solvents were you exposed to?
How long have you been using gasoline?
Have you ever been exposed to gasoline fumes while fueling your vehicles.
Did you use MEK while washing down aircraft?
Do you drink alcohol (methanol)?
Have you spent any time around people who have painted their fingernails or toenails?
Have you spent any time around people who used nail polish remover?
Have you ever had your hands in used motor oil?
Have you ever not worn safety equipment when doing any of the above?
/
Since the house is on fire let us warm ourselves. ~Italian Proverb
Very interesting.
Thanks, Gretchen,
-Jazzdogg-
"Don't ask yourself what the world needs. Ask yourself what makes you come alive, and go do that, because what the world needs is people who have come alive." Gil Bailie
Thanks for posting the link. I have always been cautious about breathing the fumes and absorbing it through my skin, although I didn't see anything about skin absorption in the link.
-Jazzdogg-
"Don't ask yourself what the world needs. Ask yourself what makes you come alive, and go do that, because what the world needs is people who have come alive." Gil Bailie
Thank you Gretchen, I'm 63 next month. The data I read said that even in cases of severe ingestion of the fumes it disapates and is not cumlulative, but today excepted I am very careful.John
Pins,
I put my brushes in a re-cycled ceral bag and an elastic band....keeps them wet for days if not weeks...clean up one time only.
I used to use plastic bags and saran wrap but with fast-drying finishes
I like my way better. I keep my shellac brush in a jar of alcohol.John
Rich I was spraying shellac today and when I went to clean the gun I decided to try denatured alcohol in lieu of lacquer thinner. Well to make a long story short you were right. The alcohol did in fact clean the gun faster and I believe more completely. I guess an old dog can learn new tricks. Thanks,RonEdited 7/23/2006 8:31 pm ET by Ronaway
Edited 7/23/2006 8:31 pm ET by Ronaway
Us old dogs gotta stick together!
There's a product available for giving painted surfaces some tooth as an alternative to sanding, called Paso. IIRC, it's a mix of lacquer thinner and denatured.
"I cut this piece four times and it's still too short."
Ronaway,
I just wanted to acknowledge your comments because they really hit the nail on the head (padding garnet shellac is like appling a stain). I don't have any spray equipment and the last time I tried to float a stain in shellac over some birch...what a pain. Eventually it looked good....until I saw the piece in a setting sun position...I just keep it in a dark corner now. On the current project, I should have stopped with the shellac after two coats and shifted to a wipe on varnish.
However, after rubbing out alls fairly well...I mean it is wood (scraps mostly)...
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