Encouraged by the two long posts on shellac, I decided to give it a go on a shop cabinet.
I sprayed a 2 lb. cut of Zinser Amber (waxed). The first spray dried so quickly, I went over it again. I sanded with 220 and sprayed again. I repeated this and after the fifth go sanded with 320. Didn’t get the “ground glass” look so sprayed again. This time it seemed to work. Left it for 24 hours and started the process of sanding the finish. 400, 600, 800, 1000, 1200 and 1500. Used mineral spirits as a lubricant. Finished with red rubbing compound, then white polishing compound, and finally, swirl remover.
The finish feels great, but when looked at against the light, certain areas are highly polished (look great) but the overall finish is marred by random flat areas. I had difficulty in determining when to move up a grit so obviously some areas didn’t get enough. What do I do now? Should I re-spray and start again?
Moreover, how do you know when to move up a grit? How long should it take to sand say a 12″ by 24″ raised panel door at each grit? What visual cues might help?
This is my first experience with shellac so I didn’t expect to get it right first time.
Thank you for your help.
Hastings
Replies
Sanding between coats of shellac is only necessary if their are significant defects (drips or runs, etc.) to be fixed. Usually you can level such things out by sanding after every 3-4 coats. And, almost never any reason to sand with 220. 320 is course enough for most problems.
Then, if you are looking to rub out to a gloss finish there is usually no need to start at 400 grit except for significant defects. By the time you have worked through 6 grits after having sanded between coats there isn't much finish left I would think. Spray your finish--4 coats of 2 lb. cut is about equivalent to 2 thin coats of brushed on varnish, for comparison purposes. Knock down gross defects and then start at 800 or 1000 and take that to the point where there is even sheen. Make sure you have raking light to spot shiny spots. Then proceed to 1200 grit as your final grit. If you have a smooth surface with the 1000 grit, 1200 grit sanding will take only a few minutes. At that point you can easily go directly to rubbing compound. (I assume these are CAMI grits, not P grits.)
I would give it an extra couple of days before doing the final rub out. I do think shellac does continue to shrink for a while after it is nominally dry.
Thank you for the help. Had to do a Google search on the CAMI vs. P grits. I assume I am using CAMI, but I honestly don't know. I got some at West Marine and some at the autoparts store.Hastings
In the US at least, P grits will generally say that on the back--ie. 400P or 1200P, while CAMI will just have the number--400 or 1200.
Steve:You can find a chart here:http://www.cs.rochester.edu/u/roche/rec.wood.misc/grit.sizes.htmlSo, for example CAMI 600 is about the same as P1200 with a 16 micron grit size.In an earlier post Rich said, "…and you can now go on to "rubbing out" to the final desired sheen. This can be the result of 4-0 steel wool, or all the way up through 400, 600, 800, 1200, 1500 waterproof paper lubricated with mineral spirits…".I know you have no way of knowing, but would he likely be referring to CAMI? Is that the default? You original advice specified CAMI and that's a big difference. For example, I went from Cami 320 to P400, which are the same grit size (36 Micron)!Would you advise that I spray again and then rub out with CAMI 800 or 1000? Then 1200, then the compound, etc.?Sorry to keep "peppering" you with questions, but who would have thought sand paper could be so complicated.Thank you,Hastings
In the US CAMI used to be about the only type available, but P grits do show up with greater frequency. I would spray again, a coat or two, let it dry well for a few days and then rub out starting with either CAMI 800 or 1000 and then going to CAMI 1200 which scratches most medium rubbing compounds can remove OK. Then finish with what ever compound gives you the sheen you want.
There is a lot made about not skipping grits--too much I think. It takes only a little extra time to remove the scratches from coarser grits using every other grit, for example, and you are likely to remove less material over all. And, a sprayed finish is likely to require very little "sanding", before you reach the ability to begin polishing, so don't start sanding with coarser grit than is absolutely needed.
Thank you for taking the time to help me out. Sounds like a plan, particularly the leaving it for a few days.Hastings
Shellac dries for handling and recoating within hours, but the final cure takes quite a while. A few days or more is good for rubbing out purposes. Final full cure and hardness takes weeks. However, it cen be used before that.
J
Joe:Thank you. I think I mistook dry to the touch for ready to rub!I sprayed two coats yesterday, which went on nicely. I am going to leave it to one side for a few days.Hastings
Hi,
I'm ready to apply the first coat of finish to my pine bookcases. I was planning on using a wipe on oil based Polyurethane(MiniWax) but I was wondering if I'd be better off applying shellac. If I do choose to go with shellac how much time do I have to wait before I apply the 2nd/3rd/4th coat? Is it ok to use 400 grit wet/dry sand paper to sand off the dust nibs and imperfections between coats?
Is applying the shellac with a cloth ok?
Wanda
Wanda,
I'm not a big fan of poly in most cases. Shellac can be wiped on and it will IMO look much better than poly. If you want more chemical or abrasion resistance than shellac provides, I would use garnet shellac top coated with an alkyd resin varnish. I have done this on pine and it looks great.
Here is a link to a good finishing schedule for pine. The website belongs to the host of a finishing forum from another woodworking magazine. He is quite knowledgeable and a good teacher.http://www.johnjacobmickley.net/Shop%20Pages/Tips%20&%20Info/Finishing/Finishing%20Pine.htm
Here is a link to another page on Steve's sight that very thoroughly covers different application methods for shellac including brushing and wiping, both as a sole finish and under other finishes.http://www.johnjacobmickley.net/Shop%20Pages/Shellac,%20Application.htm
I hope these help to answer your question. If you have any more feel free to ask.
Rob
Edit to add: I was so busy directing you to that website that I didn't answer your questions. Shellac will dry in about 15 minutes after the first coat. Each coat after that will take slightly longer. That is for brushing. Wiped on shellac will dry very fast. Shellac shouldn't be applied with the same mindset as varnish, thicker is not better. You want just enough shellac to get the finish to look the way you want it to and no more. If you do go with a wipe on varnish, including poly varnish, you should make your own. Take any oil base varnish and thin it 50% with mineral spirits and you are good to go. Why pay someone else to do it for you. Mineral spirits is quite a bit cheaper than varnish.
Edited 5/4/2007 12:08 pm ET by Rob A.
Hi,
Thanks for the great link. I have some Bullseye shellac hiding out somewhere in my basement. I was planning on making my own wipe on poly.
What is the difference between Garnet shellac and Bullseye. I know there are 2 types of bulleye shellac .. one contains wax the other is dewaxed. I belive the can I have is unwaxed.
I might just give the linseed oil a try. Let it cure for a week and then apply the #2 shellac.
What is the difference between oil based alkyd resin varnish and MiniWax fast drying polyurethane? They are both varnishes aren't they.
Wanda
The only liquid shellac from Zinsser that is dewaxed is called Seal Coat. The others, Amber and Clear both contain wax. Also take care that the shellac is not too old. There is likely a date on the can, but better to put some shellac on a hard surface--like a coffee can lid, or a plate and see whether it dries hard.
Seal Coat is a blonde shellac--moderately light in color. Garnet is quite a bit darker, which a reddish brown tinge.
Yes, the Minwax polyurethane and the alkyd resin varnish are both varnishes and basically similar in properties, with a few differences that could be meaningful. The resins are different, with the poly based on alkyd "modified" with the addition of polyurethane resin. The polyurethane makes it a bit more abrasion resistent than the alkyd varnish, a difference of not much importantance except for floors. Polyurethane varnish also doesn't adhere well to other finishes and in particular won't stick well to shellac with wax in it. Polyurethane varnish is also more difficult to rub out to an even sheen. Alkyd resin varnish will adhere to shellac with or without the wax. The polyurethane resin is also slightly cloudier than the aklyd alone, which is what you gives the "plastic" appearance that some complain of. (This can be kept a bay if the polyurethane coating is kept thin.) In addition, the traditional resin varnishes that are relatively widely available, such as Pratt & Lambert 38, McCloskey Heirloom, or Behlen Rockhard are all well formulated varnishes that brush out and level well. I was not impressed with the brushing character of the Minwax Fast Drying Polyurethane last time I experimented with it. (That is a trade off that seemed to be associated with the fast drying.)
Wanda,
Steve S.did a good job answering your questions so the only thing I would add is that the shellac in the finishing process outlined in the linked article is not only there to provide protection and depth but also to add color. Think of it as the stain you will be using on a wood that is notoriously difficult to stain. So in that sense if you are happy with the color of the pine after the BLO application, then you would want to use a blond shellac, if you are looking for the orange color that Steve Mickley achieves in the article you can follow his advice to use a burnt sienna dye mixed with garnet shellac as a toner or orange shellac. I used straight garnet shellac and got a really nice golden glow.
As Steve S. suggested check the date on your can of Zinsser and if it is more than 6 months old you should do a test on it. A good way of testing shellac is to drip a puddle of it on a nonporous surface then stand it on edge so that the puddle runs off, the film that stays on the surface should be hard within 15 minutes or the shellac is no good. Mixing your own shellac from flakes offers the advantages of knowing that it is fresh, faster drying time, more color options (almost unlimited options if you mix grades), availability of dewaxed shellac in most grades.
Rob
A shellac finish is quite nice but applying with a cloth is not the same as a wipe on varnish finish. It dries VERY quickly. I am not sure what you will gain by applying shellac, since you are not familiar with it. As has been suggested, if you are pleased with the look of the case after applying BLO then finishing with a wipe on varnish--either poly (which I never use) or non-poly will give you a nice finish.If there is a "blotching" issue then a coat of shellac under your final finish may be helpful. You can approximate what your case will look like with a clear finish (shellac or varnish) by wiping it down with mineral spirits. What it looks like when wet with the MS will be what it looks like with shellac or varnish (absent any colorant in these) as the final finish. This will also tell you if you want some stain--or the BLO. The latter can/should be done first on a scrap before committing to the entire project, of course.
Gretchen
Edited 5/7/2007 8:27 am ET by Gretchen
Hello Gretchen,
The only time I ever used shellac was when I had to seal knots on my adirondak chair before painting it.
I was planning on applying BLO using the method described in the article that was posted here on the forum. They said to apply a Liberal coating of BLO, let sit 30min and then wipe off the excess with a cloth. Do you think I will have issues with blotching? If I am satisfied with the colour of the pine after applying the BLO I will apply several coats of wipe on varnish. Non-poly kind. Not polyurethane which I have used in all my other projects. Natrually I will test this out on a scrap piece of pine first before applying it to my project.
Do you apply shellac using a cloth or varnish brush?
Wanda
Steve:Yesterday I sanded one of the two cupboard doors after leaving it for a few days. It came pretty nicely. If you get it against the light, you can see a few places where there is a little uneveness. I give it a 5 or 6 out of ten. My mother-in-law thought it was wonderful!There is, however, a tiny area where I rubbed through the shellac; do you have any suggestion as to how I might "repair" that?Thank you again for your help; it made a big difference!Regards,Hastings
Hastings,
Applying a shellac finish is essentially the process of putting enough "material" (resin) on the wood until you can easily level it out with a cushioned, flat abrasive pad (a sanding block) with about 220-320 grit. All the schedules that have been posted here (by myself and others) are simply ways to get to that final condition. Once that has happened, enough shellac is in place to carefully rub it out with finer abrasive material up to the final appearance that one desires. That final appearance can be the surface produced by 4-0 steel wool (at one end of a spectrum) or polishing compound/swirl remover at the other end (or any one of a number of steps in between).
You simply don't have enough shellac on the wood. That's why you rubbed through. Simply apply some more and gently level it out. Keep applying/letting dry/leveling, until you can get a completely even, smooth surface at about 220-320 grit. That's when you're finished applying shellac. Whether you level between each application, as I do, or put down many applications without leveling in-between, it's no more complicated than that.
Rich
Rich:Thank you for your advice. I have many of your posts in my shellac file so I understand what you are saying intellectually - it's just doing it!I thought I had enough material on the wood, but obviously I didn't.Although not perfect by a long shot, the door for the most part looks very nice and I can see the potential in a shellac finish for showing off the wood.Regards,Hastings
Hastings:
Rich's advice is spot on, of course.
The deal is, that because shellac is an evaporative finish, subsequent coats just blend in with the original ones. They don't necessarily melt all the way through the earlier coats, but they do combine seamlessly.
If someone had just discovered shellac, it would be marketed as a wonder finish -- beautiful, fairly straightforward to apply, very easy to repair, non-toxic and hypo-allergenic when dry (edible even...), exceptional vapor barrior, and exceptional barrior to sap and oily stains.
I almost forgot -- shellac is a renewable, and "green" resource as well.
Joe
Edited 5/8/2007 9:48 am ET by Joe Sullivan
Hastings, a mundane question here: What is "swirl remover?" I must have missed this in the previous (incredibly long) shellac threads. TIA!
FG:"Meguiar's Scratch X – Fine Scratch and Swirl Remover"I got it at the autoparts store. From the back of the tube:"The most effective way to safely remove (sic) fine scratches and swirls"It is the final step of the three post-sanding steps suggested, i.e., rubbing compound (red); polishing compound (white), and then finally, swirl remover.Regards,HastingsPS I put the "sic" in as I didn't want you to think that I had mistakenly split the inifinitive in transcribing the wording on the tube! :-)
Bravo for being sensitive to split infinitives.
I probably split an infinitive at least once every day, so no worries about me nailin' you on it. ROFL!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
If you keep your tools sharp, you can consistently split infinitives to your heart's content. Using the scary sharp method I can split them to .001". I can only do this a few times before the tool loses its edge though. Don't try this with something like a Stanley just out of the box or you will end up with a buch of fragments.
Gotcha! I'm still working on my Scary Sharp technique. Once it's perfected, might be a great way to conduct comparative tests on various high-end chisels!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
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