I used a spray gun attached to my air compressor (who knew? I thought all that thing was good for was to blow sawdust out the garage door) to put 10 coats of 1# (approximately--Zinsser store-bought, you see) cut on a blanket chest I bought for my wife. I somehow or other managed to load up the finish in a couple of spots, and I'm feeling some apprehension about a few things.
Did I put on _too_much_ shellac? I passed the point at which the wood grain of the cedar was, um, still visible. What I mean to say is that viewed from a very oblique angle, the finish looks like poly, or epoxy, or whatever. Except, that is, for the orange peel.
If I can fix it, how do I do it? I realize that I can just rub it out with denatured alcohol until all of the shellac is off the wood, then start over. However, I would rather not do that.
2a. If I wet sand (presumably with 400 grit and mineral spirits) right through the finish, how hard is it to match the finish? There's no stain on the chest, it was raw cedar, so I don't have to worry about that.
Can I spray a coat or several of maybe 1/4# cut with the hope that all the alcohol will somehow flatten out the finish?
Will a few coats of wax fill in the small voids in the orange peeled finish?
Am I just screwed?
What I was looking for, originally, was a dead flat, shiny finish for this blanket chest. I would hope that that's what I can still get from what I have. Is that a reasonable expectation for shellac? I'm sort of flying blind here, as I'm new to the whole shellac thing.
-Phil Crow
P.S. The damnable thing about polyurinestain is that it ain't very pretty, but at least it's predictable (to me, at least).
First off - orange peel only happens one way. Your first coat or two were too dry. It may be because of poor atomization of your gun, or it may be from poor technique. Bottom line - too dry. You end up with little bumps of material on the wood with lots of spaces between them. Next thing you do is put more coats on and it starts to fill in the spaces, but it also builds up on the bumps. As you build up coats, it flows together a bit and you end up with those gorgeous orange peel finishes. To prevent this, practice with your gun (read the directions that came with it and set it up properly). Learn to spread on a layer of finish rather than fog on coats. The delicate balance is in laying down a nice wet coat without getting runs. Practice makes perfect, but wet coats finish smoothly, dry coats don't.
400 is too coarse. Start with 1000 and moderate elbow grease. See how it goes. Don't rush it, keep sanding and use a sanding block to keep the sandpaper nice and flat to the surface. Try wrapping your sandpaper around a paint stirrer and use it. You should be able to knock down a lot of orange peel with 1000, but if it's not going down, then move down to maybe
800 or so. Be careful in how fast you move down in grit though or you'll burn through your finish. No need to do that. Sand it down until it's as flat as you want. You can get it all the way down to the low points (the craters) of the orange peel with no risk, but once you hit the bottom of the craters, you shouldn't push any further. Wet sanding helps keep the paper from clogging up so bad and makes the cutting more consistent.
Maybe - I really don't know how shellac reacts. Try it with one wet coat and see what it does. The worst that can happen is that you go the route of sanding it.
Bad approach. Get your finish where you want it and then add wax.
Nope. You're just not done yet.
Dead flat huh? Well, then wrap that sandpaper around a paint stick and grab a small bucket of water and get sanding. Flatten it out nice and then rub it out with a rubbing compound to get it back to the level of shine you want.
That's basically what I said in the other part of my comments that you snipped. I realize I made it a bit confusing by posting the comment below and then elaborating more later on, about how to deal with orange peel. My bad.
About 1 1/2, it is Zinser (sp?) 3 lb cut about 50%. I try to wipe a very thin coat, but I get too much drag unless the pad is wet, rather than damp. At that point it is laying down a layer that is thick enough to show the marks of the pad. I'm going to try thinning it to less than 1lb tonight to try to get this thing finished.
If I want to sand to get a smooth surface before this (hopefully) last coat, some have suggested wet sanding with mineral oil, others with water(?), others let it dry thoroughly and dry sand. Any thoughts?
As a spraying newbie, how do I know how wet is too wet? My guess is to cut the spit out of the shellac and spray it on so thick it _almost_ runs, but if I knew what I was talking about, I wouldn't be here right now, would I?
I'm assuming water is the appropriate solvent for wet sanding, based on your comments, or is mineral spirits a better wet sanding medium? The reason I ask is that, from my very limited shellac knowledge, water is like, well, water. You know, grain raising, not playing well with other finishes, etc.
Rubbing compound? Would that be the same rubbing compound I would use on my car? Or is there a WW compound that works better or faster or whatever? Regarding dead flat, is that what folks are looking for (sometimes) when they decide to use shellac? In the future, would lacquer maybe be a better idea for a flat finish? Not knowing the difference, and having some shellac and a spray gun (a truly dangerous combination indeed!) I figured I'd give it a try.
Thanks, Mike, for all the help. I sure appreciate it.
wrote in message news: snipped-for-privacy@f14g2000cwb.googlegroups.com...
Hey Phil - I'll preceed everything I have to say by saying that I don't finish with shelac so my comments are strictly related to spray painting techniques and practices. Others can augment what I have to say by bringing shelac specific knowledge to the conversation. A lot of these things are universal, so the discussion is meaningful.
This would be a universal question. You are right in that a good wet coat is on the verge of wanting to sag or run. But... it won't because you didn't put it on that heavy. Nice and even. Think of it as spreading plastic wrap over your workpiece. You want to envision yourself doing exactly that with your spray gun. It will take practice to develop the ability, but the key is to be able to watch your spray going on. You can't do this stuff by feel until you've spray painted for a good long time. Even then, because of an infinate number of variables like humidity, temperature, etc. you will find that you have to always watch the spray pattern going on the workpiece. This means good lighting. Don't take a shortcut on the lighting. No shadows, no glare, good well lit work area. Make sure each pass just overlaps the previous pass and it creates a growing wet surface without overlapping too much and creating an area that is too wet and sags, or that is too far apart and creates a dry line. The edges of your spray pattern out of your gun are dryer than the cigar shaped center of the spray pattern. This works to your advantage. The top of your first pass will be a little dryer than the center of it, but when you overlap slightly on the second pass - with a slightly dryer bottom to the pattern than it's center, the overlapped area ends up receiving essentially the same amount of paint as the center of the spray pattern. Am I making sense? You should be able to watch your "plastic wrap" grow as you make your passes up the workpiece. Nice and even in wetness and texture. No dry spots and no heavy spots. Study your owners manual for your gun. It will give you valuable information on tip sizes for various viscosity materials. Live by that information until you develop spraying skills.
Practice on scraps. Lay some down flat and experiment. Your owners manual will tell you about setting up your gun. You'll need to adjust the spray pattern for a nice cigar shaped fan and you'll need to set your needle for proper atomization. The later is very interactive and dependent upon the pressure setting. Hold your gun about 6" from a vertical piece of scrap and as quickly as possible, just pull the trigger all the way and immediately let off. You should typically have a pattern that is about 8-10" high and maybe 3" wide. The pattern should be a vertical eliptical shape - or cigar shaped, nicely rounded and defined - not a blob. The edges should fade out to nothing. You should not have an evenly wet cigar. The fade is rather abrupt - not a gentle fade. So - you have a nice wet center that is maybe
7-9" high and 2 inches wide and it fades a half inch or so on each side. Depending on your gun you may not be able to hit those dimensions, but you get the jist.
Practice by pulling the trigger all the way and developing the speed that is right for making a nice wet, shiney spray pattern across the scrap. Make a few passes - overlapping each other to achieve an nice even coverage. That's your first focus point. Always pull full on the trigger and use speed to regulate your coverage as you move across the piece. There are times when you will fog with less than a full trigger pull, but this requires a careful eye to fog and watch build up until it hits the right level. Not for the intial practice. Concentrate on developing a body rhythm. After you get a feel for this - and it will take you a few scraps of wood, move on to trying the same thing on a vertical piece of wood. You'll find - as you probably assume, that you have to speed up a bit because the vertical piece will sag quickly with the same amount of material as the horizontal piece accepted. Just keep thinking about stretching plastic wrap and watch the material go on the workpiece.
It may not seem worth it all and in fact for some pieces, it probably is not worth spraying. There's cleanup and all that stuff to contend with when you spray. But... for other pieces, you just cannot beat a sprayed finish. When you want it, you need to know how to do it.
I tend to use the term water when referring to wet sanding out of habit. Others like to use mineral spirits and for woodworking I'm sure it's fine. I would not worry about raising grain, as that becomes less of an issue as buildup happens. Once you seal the wood well you should not have a problem with raised grain. If you prefer mineral spirits though, it should work just as well. Forget the stuff about mineral spirits lubricating better than water, as I've read here. There's not a lubrication issue in wet sanding. The liquid does help cutting as it keeps the paper from clogging, but water will do this every bit as good as anything else. Most wet sanding is done by hand and there just isn't going to be a friction issue in that case, and even wet sanding with a DA or a ROS (not sure what a fan I would be of that), if done properly - slowly, will not create friction issues if done with just water. So - pick your poison. Either one will work. Again - with respect to shelac, others may have some input relative to it that I would have to defer to.
Yes - you can use the same rubbing compound that one would use on a car. I have lots of it around here, so that's what I use. Others use compounds and materials that I'm not familiar with and they seem to like the results. They'd have to offer their comments on this practice - I'm just not familiar with anything besides good old 3M rubbing compound.
Shellac and lacquer give two different finishes. Again - I'm not well versed in the use of shellac so the other guys can chime in, but as I understand it, shellac does not really seal - it more fills. As I understand it you typically overcoat shellac with a sealer of some sort. Lacquer is a sealer. It fills by build up in a way similar to what shellac does, but it also seals. For dead flat I would probably go with just lacquer as long as the look of lacquer is what I was after. I wouldn't bother using anything else to fill the grain since the lacquer is fully capable of doing that and subsequent coats will provide the buildup. I'd lay it on as smoothly as I could and then I'd either wet sand it with 1000 or 1500 and buff it out, or if I sprayed a nice smooth coat I'd skip the wet sanding. All that said - that's only to answer your specific question about shellac vs. lacquer. Then there's oils, etc. We won't go there for now...
I just got done spraying a '52 Dodge over the weekend. Some of the panels came out like glass and I'm just going to bolt them back on the car. Some panels orange peeled a bit due to some problems I had with my gun. I'll knock those down a bit with 1000 and then buff them out. There's just no absolute rules. Sometimes it all just comes together and the dust gods aren't paying attention to you and you end up with a really nice, ready to go finish. Sometimes it just don't work that way. Other times you want the protection of a particular finish - for example, lacquer, but you really don't want a high gloss plastic look. So - you knock it down with steel wool to flatten it back. There's just a ton of options.
I'm not an expert, but I can do a search on Google Groups. Here are directions from "Paddy Odeen" about how to do this. He posts on rec.woodworking about shellac issues now and again:
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Cut your shellac to #1.5. This should be plenty thin for wiping, which is what I always recommend for beginners. Heck, it's what I recommend for everyone. Yes, you can brush shellac. Yes, beginners can brush shellac. Yes, beginners almost always have a spazz when attempting to brush shellac, especially thick cuts. Don't ask me how I know this. Take an old sock; wool or cotton will work. Get a piece of an old pillow case or table cloth and wad it around the sock, pulling it tight so there are no wrinkles on one side. Dip it in a bowl of your #1.5 cut of spiffy shellac. Squeeze it out until it's just damp. You're wearing vinyl gloves, aren't you? Good. Now wipe the pad on the scrap. Take s short break. Count some nose hairs in the back of a finely polished chisel blade. Then wipe some more. Repeat.
When the pad begins to streak, do the dip-and-squeeze trick in your bowl of shellac. When the pad begins to stick to the workpiece, use a couple drops of mineral or raw linseed oil on the outside of the pad to lube it. When the shellac is dry, the oil will clean off with mineral spirits.
Let the shellac dry a couple days, come back, and mebbe one of these geniuses will tell ya how to rub it out to a glassy or satiny sheen... whichever is yer fancy. If we can't locate a polishing genius, we'll then I'll be back. Best of luck. Hope this helped. Paddy
Yep. That's exactly the instructions I am trying to follow and it isn't working out too well. I've been messing around with shellac on a couple of projects now and really love the color and such, but I simply *cannot* seem to get anything approaching a smooth surface. I'm about to give up and just slap on some poly to get this project finished. I've been trying to get a decent finish on it for 3 weeks now and it still looks lousy.
That looks exactly like what I'm doing, but I end up with all this little ridges in the finish so it doesn't have that smooth, level, shiny look. I just set about wet sanding it all back down flat and will try one more time.
Could always just use a brush. Works for me. Brush and sand, repeat about
10 times and enjoy. The results are fantastic, and I can't see how a French polish could be any more luxurious to behold. Faster way to get there, arguably that could well be true, but I'll go head to head against anybody on the final results. Shellac is very forgiving, and you can take as long as you need to get it where you want to be.
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