Replies

1. 
   david_sorg | Oct 15, 1999 08:43am | #1

   *
   David;

   The bad news is that you can't get a really decent polished finish with any water-based materials yet. Their hardness is a rubbery type of finish as opposed to the much more brittle hardness of lacquers, shellac, or (alkyd)varnishes. The water-based products will not "accept" the finer and finer abrasives as a polish, but will instead tend to cloud, like the back window of a convertible.

   That said, you can get a shinier final finish by leaving the last sprayed coat untouched, -but you can get a smoother finish by following the same steps as polishing a solvent-based finish. 600 grit, then 1000 or 1200 grit, then 1500 or 2000 grit, -all used wet, of course. Then rubbing compound or pumice, followed by polishing compound or rottenstone. Power buffing is far more effective than by hand. I use foam pads because they don't get material build-up and are less likely to burn the finish, especially on edges or details. I prefer automotive compounds; they're easier to use and less messy than the stone powders.

   Wax will not add any depth or shine to a well polished finish. It will only add slightly to the protection of the finish. I use it on table tops, but otherwise omit it.

1. 
   David_Barns | Oct 15, 1999 11:31pm | #2

   *David,Thanks for the info. I'm going to give your suggestions a try and see how they come out. Do you have any product names of the auto. rubbing or polishing compounds or can I just go to an autobody supply and get a standard type?Thanks again.David.

1. 
   david_sorg | Oct 17, 1999 06:29pm | #3

   *David,I use Meguire's #1 or 2 (#1 is more coarse, but faster) to rub, and polish with their #9. I've also used Turtle Wax and 3M products; any of them probably work fine, but I've gotten 'used to' the Meguire's and now prefer it. I probably just bought into the sales reps' pitch, which I've long forgotten, but remember being impressed at the time.

1. 
   Andy_Charron | Oct 18, 1999 09:08pm | #4

   *I have to respectfully disagree with your statement that you can not rub out a water-based finish to the same degree of shine and depth as a solvent based finish. There are many products on the market today that can be rubbed to a deep, high gloss. I know, because I have tested dozens of them and have achieved polished finishes that are virtually indestinguishable (sp?) from lacquer. (See FW#133, pg. 71) I would modify your comment to say that "some" water-based finishes can not be rubbed out the way lacquer can. It all depends on the brand you use--some are better than others. Your advice for the actual technique of rubbing out the finish is good and follows the exact same steps I use. I would add two things: First, be sure the finish is fully cured, not just dry. This may take anywhere from several days to a week or two, again, depending on the brand. Second, although automotive compounds are easier to use than pumice and rottenstone, I avoid them when working with water-based finishes. The pre-mixed rubbing pastes contain solvents that may (note I said "may") soften the finish as you rub. The more you rub, the softer the finish gets and the duller the shine becomes. As you point out, it is impossible to rub a soft finish to a high gloss.

1. 
   Rich_Farwell | Oct 28, 1999 09:34am | #5

   *A word of warning: I have read postings elswhere by woodworkers using rubbing compounds on Oak and walnut and then not being able to get the compound's white residue out of the pores

2. 
   Bill_Arnett_Jr | Oct 31, 1999 03:47am | #6

   *Any names of water-based finishes that you like?

3. 
   Andy_Charron | Nov 01, 1999 09:00pm | #7

   *In my shop I use UltarStar which is made by M. L. Campbell. It is designed for commercial use only and may not be readily available to a home or hobbyist shop. I also like the products made by General Finishes, Target Enterprises, Cash Coatings and Compliant Spray Systems. All of these are easy to work with, dry fast, look good and rub out pretty well. For more info on them check out the review in FW#133.

4. 
   David_Barns | Nov 03, 1999 01:33am | #8

   *Hi Andy,I have some questions regarding UltraStar.How long to dry between coats? How long to dry before sanding? How long to cure before rubbing out? How many coats to achieve good depth?Thanks for all your help.David.

5. 
   Andy_Charron | Nov 03, 1999 06:14am | #9

   *In regards to UltraStar:How I apply this finish depends on what I am finishing. Most of my work is production oriented parts for other people's products and don't demand a real high quality finish. In these cases I spray one coat of sanding sealer, let it dry anywhere from 15 minutes to 1 hour (depending on the conditions), sand smooth with 220 grit paper on a palm sander and then spray one top coat. On slightly higher end jobs I spray either two coats of sealer and one topcoat or 1 sealer, 2 topcoats. Again, how long I let it dry between coats depends entirely on the temperature and humidity. On warm, dry days I sand and recoat in 15-30 minutes. On cold or damp days I may wait up to 2 hours. When applying more than 2 coats, I generally sand the 1st coat with 220 grit. The second coat gets sanded very lightly with a 3M sanding sponge (fine grit) and this is only to remove any dust or defects in the 2nd coat. When putting a real quality finish on a piece of furniture, I usually put 3 coats on most surfaces but may put a 4th or even 5th coat on a high use area like a table top. I wait a minimum of 3-4 days before rubbing out any water based finish. The longer you let the finish cure (within reason obviously) the easier it will be to rub out. If you have the time and patience, waiting a week or even two will make the finish eaiser to rub out, especially if you want a high gloss shine. Hope this helps.

6. 
   David_Barns | Nov 05, 1999 07:00am | #10

   *Hi again Andy,I'm having some problems spraying the Ultrastar.I've got a piece of oak 16"x60", stained with a burgundy, water based, aniline dye. Prior to staining I filled all the pores. I'm using an HVLP sprayer, 3 stage turbonaire, with a 2mm tip and needle, #2 air cap. I'm at about 5psi and 105cfm spraying the piece horizontally(like a table top). My finish is drying with thousands of tiny pin holes and I'm not sure what to do to correct this problem. Should I thin the Ultrastar,more or less pressure, smaller or larger tip, lighter or heavier coats? I'm at a loss, any suggestions? Thanks for your time.David.

7. 
   Andy_Charron | Nov 05, 1999 10:18pm | #11

   *Pin holing is usually a result of one of two things (or a combination of both). Either you are applying the finish too thick, or there is air trapped in the pores of the wood that is then popping through the finish to the surface. Since you filled the pores first, I would doubt it is the later. How thick are you applying the finish? Do you have a finish thickness gauge to measure this? If you don't have one, contact the M. L. Campbell supplier and ask them for one. In general the finish should be sprayed between 3 and 4 mils thick when wet. If you spray it significantly thicker than this (say like 6 mils or more) the top of the finish skins over before all of the solvent has had a chance to evaporate. As the solvent works its way to the surface, it pops thorough the skin on the top of the film. To solve this, try spraying thinner coats or thin the finish a little. I have found that with water-based products, it is better to spray a bit too thin than too thick. A thinner finish may require an extra coat to build properly, but you won't run into problems like pinholing, drips and sags or a mottled finish.Hope this helps,Andy

8. 
   david_sorg | Nov 06, 1999 03:42am | #12

   *You might also try adding a couple of drops of liquid dishwashing detergent to your thinned mix; it will increase your flash time and improve flow-out.

9. 
   ribburg | Nov 15, 1999 03:26am | #13

   *Andy,I hope you don't mind helping on this matter too.I've been trying to find a water-based product that works well, by that I mean: not having too much bubbles and having no delayed effects to your heath. I used Zar before and only 5 seconds from when I first touched the wood with the brush, I saw a bunch of bubbles already, no matter how careful I was. I also tried the polyacrylic from Minwax which was so much easier to use but then it has the warning about delayed effects -- brain damage or nervous system damage...In your previous message, you said one of the products you like is made by General Finishes. Have you noticed if there is such warning on their cans? I've been looking around and have two potential candidates: General Finishes and Aqua-Cote. Do you have any suggestions about choosing one?Thank you so much in advance.

10. 
    Andy_Charron | Nov 16, 1999 01:56am | #14

    *I have not applied Aqua Cote with a brush, only sprayed, so I can't say how easy it is to brush. I have brushed General Finishes products and found them very easy to use. Much better than Zar and Minwax. In fact, if I were going to apply a water-based finish with a brush, I would probably use one of the General Finish products. As for warnings, General Finish doesn't say anything about "delayed" effects. Obviously long term exposure to most products is not good, but I would think if you are brushing on the finish in a well ventilated room you should have no trouble. If you are spraying, wear a respirator and be sure there is good air movement.

11. 
    ribburg | Nov 16, 1999 11:19am | #15

    *Hi Andy,Thanks for the info and for checking out the cans. I think I'm going to give GF a try. I always wear a respirator while brushing a finish product; but sometimes I still smelled it a little bit. I don't know if the mask doesn't fit well or that's the way it is. I only have a 3'x5' window to open so I put a box fan on it to sometime suck/blow the air out/in. Every now and then I did the finishing outdoor but mostly not, due to the outdoor temperature. Thanks again.