Replies

1. 
   TomMGTC | Oct 14, 2004 03:36pm | #1

   How long does the poly take to dry?? My guess is you are getting dust particles in it during the drying process not during application. This is a big advantage to sprayed laquer finishes.

   Tom

   Douglasville, GA

1. 
   franky | Oct 14, 2004 03:54pm | #2

   The artifacts appear as soon as the finish is applied to the surface. I'm also applying the poly to a different  top entirely with the same results. I'm about to try purchaseing the third can of poly from a different source to eliminate the poly as being the source of the problem.

1. 
   nikkiwood | Oct 14, 2004 04:32pm | #3

   What brand of poly are you using/ Have you used it before without problems?

1. 
   franky | Oct 14, 2004 06:56pm | #5

   I've used the poly before, Minwax,but not the other which is Mosers. Whats new to me is the fact I'm using a gloss finish instead of satin.

   Edited 10/14/2004 4:43 pm ET by frANKY

1. 
   nikkiwood | Oct 15, 2004 04:34am | #8

   If you have had this problem with two different brands of polyurethane, that argues there is something wrong with your technique or too much dust in the ambient air.

   Howie and Charlie have done a good job spelling out the steps; so if you are confident of your technique, then haul your piece to some place where there is less dust. If you are trying to varnish in your shop, that will almost certainly create problems -- even if there is no obvious dust in the air.

2. 
   HowardAcheson | Oct 14, 2004 05:34pm | #4

   I don't really know what you mean by "ARTIFACTS" (BTW, using all CAPS is considered yelling which is not what you intend probably).

   In preparation for applying the final coat, the steps are to scuff sand for adhesion, vacuum off the dust, get out your finishing supplies, turn on your air cleaner and leave the area for a couple of hours. Change your clothes and go back into the finishing area trying not to stir up the air too much. Wipe the project down with a rag lightly dampened with mineral spirits and then apply the finish.

   Applying finish is a learned process. For varnish, it should be flowed on with minimal back and forth brushing. Use long strokes and then go back and "tip off" the area you just coated. The tipping off will break up the bubbles and allow the finish to flow out correctly. Most oil based finishes will flow out better if you thin them about 10-15%. Once you get the finish on, get out of the area until the surface is no longer tacky.

   Most buggers you get in a varnish finish are caused by things floating in the air. You have to let them settle down before finishing.

   Howie.........
1. 
   franky | Oct 14, 2004 07:01pm | #6

   Sorry about the caps. What I mean about artifacts is small particals of dirt that are laid down with the finish not on the surface but within the finish.

1. 
   CharlieP | Oct 15, 2004 01:07am | #7

   Sometimes a brush will shed small particles if it was not perfectly cleaned.  The dry specks of finish hide in the heel of the brush.  Nothing makes them come out (compressed air, shaking, etc.) until the brush is loaded with the next layer of clear finish, where the particles can cause the greatest damage.  If you look in the center of the brush, you may see a few there, but they will seem firmly attached until they can ruin your finish.________________________Charlie Plesums  Austin, Texashttp://www.plesums.com/wood

1. 
   franky | Oct 15, 2004 03:49pm | #10

   Thanks Charlie for the info,but I also tried using a sponge brush with the same results.

1. 
   Alan | Oct 16, 2004 12:16am | #11

   frANKY,

   You've answered your own question.  If you've tried two different varnishes and two different brushes, all that's left is your technique and the environment.  You sound confident that your technique is good, so....

   Others have given you good advice about minimizing environment caused problems.  I'll add one more:

   I've found it helps a great deal to water down the floor and heavily mist the air--assuming, of course, water is welcome in the finishing area.

   I water after I've swept and vacuumed and waited for any dust to settle.  The water mist seems to grab dust out of the air, and the water on the floor keeps dust from rising again.  I wait a little after I water; but I begin work before the water evaporates.  If the floor dries up in the middle of a session, if possible I put more water on the floor.  It makes a big difference.

   Alan

2. 
   jackhall | Oct 16, 2004 02:56am | #12

   I have the identical problem using brush-on lacquer.  No matter how much effort I put into filtering the lacquer, wiping down the surfaces, cleaning the brush, etc. I see these small "artifacts" immediately as I apply the finish.  I am sure it is simply caused by airborne dust particles which, in my situation, cannot really be eliminated.  The only solution I have found is to forgo the high gloss finish and, after the final coat, use 400/600 wet/dry sandpaper and 0000 steel wool for the final rub-out.  You can come up with a high quality sheen and no visible "artifacts".

3. 
   franky | Oct 16, 2004 02:54pm | #15

   The last thing I tried was to grab the 2 tops bring them in a room thats not used and absolutly clean, wiped the tops down with mineral spirits, soaked the sponge brush in minerial spriits,the poly has been filtered with 3 coffee filters stacked over each other. when I applied the gloss poly, I got this fine mirror finish,with small specks.The Key word here as you mentioned is as soon as the finish is applied these specks show up.These specks might be coming from the surface of the top certainly not the poly or the brush. I'm waiting overnight to apply the next coat, I'm sanding beteen coats, 400,600,1000. I have many times used poly in satin and semi but this is the first time in gloss. I probably will top coat the 2 tops off with high gloss wipe on poly or as you suggust waiting for the finish to cure and rub it out to see what kind of finish I get. thanks Franky

   Edited 10/16/2004 8:01 am ET by frANKY

4. 
   HowardAcheson | Oct 16, 2004 08:03pm | #16

   >>I'm sanding beteen coats, 400,600,1000.

   Between coat sanding like that brings nothing to the party. There are two reasons to sand between coats. One is to flatten (not smooth) the surface and the second is to promote adhesion between the coats. For flattening when using a varnish, 320 or 400 is enough. Use a sanding block and sand in the direction of the grain. For sanding for adhesion, 400 is all you need. You will get not better finish sanding above 400 grit. You are just wasting your time and sandpaper.

   Next, filtering your varnish is not necessary unless you are working directly from the original can--which you shouldn't be doing. You should open the can and pour your working amount into a clean container. Then immediately seal up the original can. Do not work from it or ever pour used finish back into that can. I have never seen any contamination in a freshly opened can of finish from a reputable manufacturer. If there were, I would get to the manufacturer immediately. Whatever boogers that are getting on your finish are coming from the brush or the environment, not the finish.

   I have finished maybe a hundred transoms of fine yachts using varnish. Of course, I worked either outdoors or in a shed--not a very dust free environment. However, with good brushing technique, I could lay down a glass-like finish with almost no boogers. But, I had a good teacher and did lots of practice.

   Finally, I will say that getting a perfect from-the-brush finish using varnish in an uncontrolled area is virtually impossible. It's just there is always something in the air and it doesn't take much. That's why, to get a perfect job requires that you "finish the finish" after it has fully cured.Howie.........

5. 
   franky | Oct 17, 2004 05:03am | #17

   Howie; thanks for the professional advice, I very much appriciate it. Now you said not to bother sanding above 400 grit . OK, when should I go to 600 grit or finer? When It cures and  I start rubbing the finish Out ? I finished sanding the boogers out should I let it cure then rub it out ? If so, how do you finish the finish ? Thanks again  Franky

6. 
   HowardAcheson | Oct 17, 2004 09:03pm | #18

   Well, you're starting to get into an area that needs more space to fully answer. First, let me suggest you get Jeff Jewitt's newest book on finishing called "Taunton's Complete Illustrated Guide to Finishing (Complete Illustrated Guide Series). You can get it at Amazon.com. It is the best book of all aspects of finishes and finishing.

   Finishing the finish has to do with modifying the natural, just dried feel and look. You need to decide on what you need to accomplish and then you need to know about the limitations of the finish itself. For example, you can not increase the gloss of polyurethane finishes. Poly is added to varnish to increase scratch resistance. Rubbing a finish is scratching and poly does not scratch well. In addition to assist poly to be more scratch resistand and durable, it is generally a softer finish. The best finishes to work to a high gloss are the hardest finishes like shellac and particularly, lacquer. The highest gloss you can get from poly is that which is first dries to.

   However, you can smooth and dull the finish to semi-gloss or satin. To do this you must let the finish fully cure until it no longer gives off and odor. This can take four weeks or more depending on the environment and the thickness of the coat. To rub varnish start off with 400 W&D paper and a mineral spirits lubricant. Use a sanding block and sand in the direction of the grain frequently wiping the surface until it has a uniform gray look. Now go to 600 paper and do the same. If you now apply a coat of paste wax using a white scotchbrite pad working in the direction of the grain, you well end up with a soft, satin finish. For a semi-gloss finish go from the 600 paper to 1200 and then wax. With some polys, you can use an auto material called "polishing compound" applied with a power buffer to get a little more gloss. Be sure to use "polishing compound", not "rubbing compound" which is more abrasive.

   That's a thumbnail version of the process. Jewitt's book will go into more detail.Howie.........

7. 
   franky | Oct 18, 2004 02:47pm | #20

   Howie;  That was a great description for finishing the finish. I'll order the book and thanks alot for the lesson.    Franky

8. 
   301 | Oct 18, 2004 07:33am | #19

   None of those "household items" you used to remove dust are meant to be lint or dust free...like the coffee filters?  Those are not made to be dust free, they are made to filter coffee.  And the mineral spirits, why do you think that stuff is clean?  You think the guys making it wear hair nets?  And a sponge brush?  I use those for applying stain and see little bits of foam rubber ball up and flake off all the time.  Try a paint applicator pad instead, use a vacuum to pull off loose bristles.  A vacuum will work wonders on a brush too, they always have a loose bristle or two.

   Use a strong vacuum cleaner with a brush attachment (to prevent scratching) instead of wet wiping.  The towels you wipe with could be contaminated as well.  Listen to these other guys, they will set you straight. 

   Edited 10/18/2004 12:34 am ET by el papa

9. 
   franky | Oct 18, 2004 03:15pm | #21

   I tried vacuming the brush and top but did not filter the minerial spririts although I did think about it. but after reading Howie's reply I'm starting to realize that the artifacts that were driving me nuts originally are not that important because they're only going to be sanded out anyway with 400 grit sand paper.  The why I'm starting to see it is to get several coats of finish on, sand with 400 grit sandpaper between coats for adhesion and the final finish applied, for removing artifacts, wait several weeks for the finish to cure, then finish the finish, starting with 600 grit and everything else involved. Did I finally get it ? I know jackhall awhile back more or less aluded to this.     Thanks Everyone

   Edited 10/18/2004 8:18 am ET by frANKY

   Edited 10/18/2004 8:24 am ET by frANKY

   Edited 10/18/2004 8:25 am ET by frANKY

3. 
   301 | Oct 15, 2004 08:35am | #9

   I had such problems with that same situation I could only find releif with paint application pads instead of a brush.  I keep them sealed in a bag until I need them, vacuum them (thouroughly) before use (occasional loose bristles) then dispose of them afterwards.  Wear a hat and clean clothes, is there dust on your rafters being knocked down by air or vibrations (foot steps)?  Do you have a cat?  Also helps to let your work space "sit" for 8 hours before and afterwards so you won't stir up any dust.  Move around slowly...no problem for me.

4. 
   Curtis | Oct 16, 2004 04:57am | #13

   Hello Franky

   what kind of poly. are you useing?

   satin and eggshell finishes have pigments to dull the finish, Ive found out a long time ago to use a high gloss finish (beacuse it has no pigments.) to build up the coats (lightly sand between each coat.) and on the last coat then I can use an eggshell or what not, for the final coat.

   Ive found those little flooties are sometimes the un mixed pigments in the ploy, its self, insteed of dust.

   I wish you luck. and please let us know if you find out how to stop your  ARTIFACTS problem.

   C.A.G.
5. 
   GHR | Oct 16, 2004 06:16am | #14

   Sometimes it is simply lack of experience.

   I used to have a finishing room - I vacuumed, changed clothes, filtered the air, and wet the floors. Still I had problems.

   Now I have saw and sanding dust on the floors and ceiling, I use my old work clothes, and I shake my varnish. I no longer have problems.

   I am sure something has changed, but maybe I just put in my time.