Has this happened to you? I built a computer/return desk project and finished both pieces in a Minwax red mahagony stain with Varathane poly for the finish coat. Looks great if you don’t get too close and start running your fingers over it. The solid wood trim doesn’t feel too bad.. but all the birch ply surfaces, including drawer fronts, feel like I threw sand into the finish. What’s weird is that all these surfaces felt fine after sanding. I followed all the rules and still came up with a disappointing finish. Very discouraging. My only conclusion is that I will, in the future, use as little plywood as possible. I’m new to woodworking and gravitated to plywood because of it’s stability, availability, price and ease of dimensioning. Now I think I’ve found the big drawback.. finishing.
bill
Replies
Bill, How many coats of the Varathane did you apply and did you scuff sand between coats?
The rough texture isn't unusual for some finishes after the first coat or two and can be fixed without too much trouble. Sand the surface lightly with 220 or 320 grit paper to remove the high spots and the shine from the surface. Don't try to make it completely smooth unless you have a number of coats of the finish already - or else you may sand through the stain. After this light sanding, apply another coat and let it dry. Sand again, and apply another coat. After 2-3 coats you should have a silky smooth finish.
Paul
F'burg, VA
another trick is after a few coats of finish on smooth out the finish with 0000 steel wool and then put a coat of paste wax over it. it's a pretty much fool proof way of getting a super smooth finish no matter what.
Bill
Welcome to woodworking! We all hate the finishing part. I personally have never had this particular problem but I've had my share of others. If its not real bad perhaps a good rubbing down with pumice and oil might knock down those bumps. If its bad a lite sanding with 220 grit sandpaper and another coat of finish.
Good Luck
les
Paul, Andrew and Les.. it's going to take a huge leap of faith to do as you suggest.. but you guys have the experience so I'm considering it. What worries me is that I tried sanding on the test board, (12" X 16" ply), that I stained and poly'd as I did the desks and got very uneven results. Some areas were left lighter than the other areas. It's made me none too keen on the idea of sanding the desks and possibly screwing it up even more. To do as you suggest.. would I use the paper on a block and just hand hold it? Thanks.
bill
Bill
If you are going to sand use a block and a very light touch. It doesn't take much to cut through your finish and stain.
Good Luck
les
Bill
ps I have found if I was going to sand through the finish it would more than likely be on the edge ( and I have). So be real careful lift your block up as you near the edge. An afterthought.
les
Maybe someone can help me out, and maybe Bill too. When you say "scuff sand", just how much sanding do you mean, and how heavy? I use a hard rubber block which has some weight to it - should I be just pushing it across the surface, letting gravity do the work? Or putting some pressure on it? Enough pressure to move the work across the benchtop unless I hold it back? And when do I stop? Someone said to remove the high spots and shine - all over? I feel that by the time I sanded it to "not shiny" all over, it would be down to bare wood in some areas. And if I took off that much between coats, as I have seen some writers recommend, I don't think I'd ever get a finish built up.
Graeme
I don't have a dust-free place to finish, and mostly use oil finishes. When using sipe-on poly finishes, what I often do is finish up with a coat of paste wax that I apply with 0000 steel wool, then hand buff with a cotton cloth. This will usually get out all of the remaining bumps - but you do have to be careful not to overdo the rubbing.
Geeseawhy;
How nuch do you sand?? 3 or 4 passes at any one place, then run your hand over it. If it feels smooth, stop and go to another area.. If it's still rough or not to your liking, take another 3-4 passes and check it again. The nice thing about oil stain is that you can match pretty well if you sand into it. I use stiff poly foam for a sanding block.
I guess i'm the oddballl who loves finishing.
*I spray solvent-based lacquer or poly, use worn-out 220 on a rubber block to knock off the nibs, repeat from * two more times, then use a ScotchBrite pad to finish. Never go past the edge of the piece with the block, only nose just up to the edge. This applies even if it's a clear coat and no stain involved; it's just good practice to not leave the finish skimpy at the edges which get the most wear.
For pressure on the block, i use about the same as i would use to wipe dust off my computer desk, if i were so inclined to ever do such a thing.
When going over stain, i don't do any sanding at all until i have two coats on the piece, then practice extra care around the edges. Sometimes the finish will lift the stain color into itself a bit until it builds, so you don't want to change the color by sanding a lot of this off. I don't bother with sanding sealers.
If you have roughness in any of the layers, don't expect that to improve just by spraying on more finish. None of the layers is all-or-nothing: there has to be a gradual buid-up of finish, each coat applied correctly and rubbed out as you go along, not waiting until the end to fix it. Well, except for that 1/4" layer of epoxy...
Splinte.. in looking at fine furniture with new eyes, (scrutinizing the finish), it has become apparant that the technique of choice is spraying.. as you do. That, of course, requires a whole new skill set in and of itself. What I still wonder about is how the professionals sand all those tight, curvy places like on the grandfather's clock I gave my wife. It has all these miniscule grooves and turns and knobs and stuff.. it would make me crazy trying to sand that thing. How do they do it, eh?
bill
They didn't have the Internet distracting them. ;~)
Edited to add that i sand all the routed edges on sculpture bases i make, then have to do the same for every finish coat. Interior curves are way more time-consuming than exterior. Two bases of similar size can cost very differently to the foundry.
Edited 11/12/2002 5:01:57 PM ET by SPLINTIE
Rather than spending hours and hours dealing with all the details that COULD be sanded, it is often better to be concerned with the quality of the machining (especially when making mouldings). If tooling marks are of sufficient number (>30 knife marks per inch) and you don't have dips and snipes, then the amount of sanding required on these surfaces is pretty minimal.
When it comes to sanding the real expertise that ensues after doing it for years is knowing when you actually do need to sand and when you don't.
Sanding can create as many or more problems than were already existing. To name a few -- swirls, cross-grain scratching, break-through on edges (stain), veneer sand through, dips (from over sanding in one area).
Using wood repair (for things like filling nail holes) can be another problem. I am always amazed that for a little bitty hole, too many woodworkers use a very big putty knife. Yep they fill the nail hole and in the process, get the putty into the grain surrounding the hole.
Thanks for the information.. especially the parts about knowing when sanding is unnecessary.. and how sanding can cause more problems than existed to begin with. I've read that it's preferable to fill nail holes *after* the finish is applied. Does this refer to after staining and before topcoat? Thanks..
bill
There is no "right" answer to this question -- it all depends on personal preferences and the techniques available to you.
If you are using wood repair (putty) to fill nail holes, and you do it before staining, then the putty will absorb the stain (well sometimes anyway) and this can lead to a dark spot that can stand out and be unsightly. A good example of this would be a nail hole in flat sawn ash latewood. The latewood is smooth (non-porous) and it doesn't absorb stain well. A putty filled nail hole is going to appear as a dark spot and be very visible.
In this same situation, if the putty color is close to the wood color, it may be better to stain, clear coat and then fill. With a light sand to even the surface, subsequent clear coats will leave the defect less noticable because at least it is "not dark".
I spray my finishes (nitrocellulose lacquers) and I work with any number of different color systems depending on the desired outcome. Sometime it involves analine dyes, glazes and shading stains (dye in lacquer) -- alone or in combination. At some level I am using all of these to "touch-up" defects by using small paint brushes. By using small brushes, I can better control where the touch-up colorant is applied and also the amount (so that I can control color intensity).
I also have available to me colored powders that I mix with lacquer and thinner and will use these as well. These are available from companies like Mohawk Finishing Products of Amsterdam, NY. During my days of on-site touch-up work, I used these powders in varnish (though they dissolved less readily). They can be used in shellac as well. Tubes of universal tinting colors (like available at an art supply store) can also be used -- the advantage of commercially available product is that they have close approximations already available (eg light walnut, brown mahagony, oak, etc). Thus if you are doing most of your work in one wood, you could get 3 or 4 close colors and blend them for a more exact match.
The most used colors in my palate of touch-up powders are yellow ochre, burnt sienna, burnt and raw umber, van dyke brown, and white. I additionally use a medium yellow and orange. I thinnly "paint" the base color (background color) and then add the graining on top especially for larger defects (cigarette burns on refinishing jobs or veneer sand-through).
The general rule is that the closer the color is to the surrounding wood and the nearer its proximity to the actual wood (and therein not in/on subsequent levels of coatings) the more natural it will tend to appear.
The greatest challenge is dealing with the chatoyance of the wood. The best way to understand chatoyance is to recognize that as eye position changes, so does the color of the wood. Thus what may appear as a perfect color match from one direction will appear as a big blob of gick from another.
If you are working on small projects, the expense and effort of detailed touch-up work is probably not justifiable. However if you are creating a true master-piece, then it might be something to consider.
My friend, if I may presume to address you as such, you are at a level I don't even want to attempt to reach. True masterpieces will never materialize from my hand, but it is illuminating and edifying to read about the techniques true masters such as yourself employ. Thank you for your generous replies.
bill
If I am anything of a master, it is only because I did my time at Penn St to obtain my Master's degree in Wood Science and Utilization. Otherwise I am only a woodworker like yourself albeit one who has had the opportunity to work with and learn from others far more gifted than myself. I "teach" because others taught me; it is the tradition of the trade and the only way it is continued. To that goal, I remain dedicated and I value this wonderful forum for an opportunity to do so that I would otherwise not have. Thank you for your sentiments.
"I "teach" because others taught me; it is the tradition of the trade and the only way it is continued."
To the extent that I ever learn enough to carry on the tradition.. rest assured that I will. Thanks for your dedication and generosity.
bill
Usually after top coat with an oil or wax base filler. That way it will not create the blotch mentioned before. You can press it into the nail hole with the back of your thumb nail. An oil base will eventally dry.
Thanks again for an invaluable tip. I'll look for the fillers you describe and hope they sell it in the shade I'm using. (red mahogany)
bill
Do you ever use pumice to rub out a finish? I have used it and had good results although I haven't used it in several years. I don't hear much about anybody using it.
les
Les,
I just rubed out a shellac finish with 600 grit and parrfin oil, I was told the 600 grit was a good substitute for the pumice. What is your opinion?
Les, i haven't used pumice (or rottenstone) since practicing with it one time and deciding it was way too much work for the return, but then i don't do the type of furniture that demands that kind of finish to be historically or stylistically correct.
As an aside, the season that i spent waiting for my finger to graft back on, i had to cut corners in finishing bec i was strapped for time and i couldn't hold the block and the work at the same time or really bear down with the nylon pad like i do. I would knock the nibs off between coats with paper, but i left the final sprayed coat as was. Well, sales were just the same, maybe better, with the glossy look. Once healed up, i went back to the time-consuming working of the final coat just bec i like it better. But there are limits...<G>
I'm building a cherry (mostly ply over MDF) cabinet. Three or four coats (I'm losing count) of padded shellac so far on the ply door panels, sanded with 320 between coats. I was concerned that the surface wasn't getting any smoother as I progressed but the replies encourage me to press on and finish with steel wool and paste wax - after *another* week to let it harden :-(
At least now I understand that a glass-smooth finish between coats is not necessary.
"For pressure on the block, i use about the same as i would use to wipe dust off my computer desk" Hmmm, let's leave that as a mental exercise shall we. By the time I cleared all the stuff off it, I'd have forgotten why I wanted to. Maybe I'll try the foam block instead of the hard rubber I always use - seems like it would be easier to keep a light touch with that.
BTW Splintie, I really liked your tables. I'm not about to try anything like that but I do have half a mind to try adapting your Navaho design into a segmented bowl, if you don't mind. It would be a challenging design/construction exercise. And when it's all turned and sanded, just slap a coat of woodturner's polish on it and it's done :-)
Thanks to all who replied.
Graeme
Graeme, i spray three coats of lacquer in a day, let it harden overnight and buff it out the next morning. Even if it's raining! You guys work way too hard...
Only caveat about "stealing" my designs (which i stole from the rugmakers, right?) is that you post the results of your lathe experiment.
Foam block: There's a painting tool that is a foam block, formed for a hand hold, with a lime green pad attached to it for holding/applying the paint. It was made for one-time use, so not expensive, but this would appear to be the Cadillac-quer of foam sanding blocks. <groan>
Splintie,
" i spray three coats of lacquer in a day, let it harden overnight and buff it out the next morning."
I do all my ww in the basement, and the only way I could make enough space for a spray setup would be to dismantle my partner's weaving loom, resulting in serious domestic disharmony - even if this cabinet I'm building is for her art supplies. I've been using shellac because it dries fast (picks up less dust) and doesn't stink up the entire house. And this after a fairly disastrous first attempt with the stuff - brushing it on, it kept drying out and leaving a really uneven surface. My reaction - slow down and try to be more careful. So when you've all stopped ROTFL....
"Only caveat about "stealing" my designs (which i stole from the rugmakers, right?) is that you post the results of your lathe experiment."
Certainly, but don't hold your breath - I told the LOML this cabinet would be done by Christmas. I carefully omitted to specify *which* Xmas. And there are a few other projects on the list too...
Thanks, Les.. but as I mentioned to Heidi's Dad, I'm writing this off as a bad, first experience and taking all these fine suggestions on to my next project. (Bookcase and shelves)
bill
Bill if you are really going to 'blow this off' with a piece of glass, you have nothing to loose. Try this. Take some 320 or 400 wet/dry or white cabinet paper and take a few strokes by hand. then follow this up with 0000 steel wool and a past wax. Don't be afraid of laying down some wax. Don't let it go dry while you're buffing with the wool. After the wax dries, buff it out with an old cotton 't' shirt or terry towel. I think you may like the results. If you don't, you're going to cover it with glass anyway. I would encourage you to go for it. This is a wonderfull learning opportunity, and as a shop teacher told me a long time ago, "flat black paint will cover a multitude of sins".
HD.. now when you say "paste wax" are you talking J&J paste floor wax like I use on my tools.. or something else. I think I'll give 'er a go since this doesn't involve another poly topcoat. Thanks..
bill
Bill; Good on ya.
J&J will work just fine. Minwax also makes a nice past wax. I have a can of bowlling alley wax. The only difference that I can tell is that J&J is a little easier to liquify. The bowlling alley stuff claims that it is a harder wax when it dries.
P.S. Be sure its good and dry before you go after it. A week anyway.
HD.. thanks.. I'll "wool 'er in" this Thursday and see how she looks.
bill
I went to work to finish 6 jewlry boxes one December & I wound up scraping off 5 coats before i got it right. My son who has an awsome reputation finishing beautiful wooden hull boats in Oakland accused me of making expensive non-skid. But when I finished the jewlry boxes had a finish like the Queen's Piano.Don't give up. keep doing it, untill you get it right. Richard
Thanks, Richard. I can't wait to try again when I'm working with real wood instead of this plywood veneer stuff that raises when you apply wet stain.. and won't take more than one or two sandings before revealing it's ugly inner child.
bill
Bill, did you per chance, use a water base sealer, or water base product at any point? Water will cause the little fibers in ply to stick up like a porcupine. Much worse than solid wood. Also, for scuffing, I use a poly foam block. The fairly ridgid stuff that computers and furniture are packed in. It can be shaped to anything you may need including flat. It's not as hard as a solid or rubber block, but stiff enough for scuff sanding.
Don't be afraid to lightly sand and apply more finish. After awhile, it will become second nature.
No, I used all oil base products.. but what you describe appears to have happened. In fact, it's an excellent description. What I've decided to do is let it remain as is.. because I've ordered 3/8" glass for the desktops and only one side and the drawers are available for tactile scrutiny. I faced in poplar and it took the stain and poly well without the grainy feel I got on the birch ply. I have movers coming Friday to get the desks from my garage/shop into my study.. so I don't want to risk another topcoat in this weather. I'll do better next time. For one thing, I'm keeping ply to a minimum in future projects. Time to become a woodworker instead of a sheetgoods worker! LOL
bill
Same thing happened to the plywood top of my workbench, after applying latex paint. I assume that this was a case of the wet layer "raising the grain." Sanding took care of it.
In some spots I sanded down to the wood, and the next layer of paint made the grain stick up again. Next time I'll use a lighter hand.
Yes, I think the application of the stain raised the grain, because the surface was smooth as can be after my initial sanding. I was loathe to go back and resand because the birch veneer is woefully thin. I've decided it's time to move onto hardwood.
bill
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