Replies

1. 
   SteveSchoene | May 25, 2006 07:10am | #1

   You can add a little distilled water--try about 10%.  Too much and the finish won't coalesce properly.  The Rustoleum web site doesn't give any technical data on their Varathane waterborne finish so I don't know what the limit is, or if another solvent could be used. 

   How long is the finish taking to cure?  Unless you have done lots of air scrubbing in your "finish room", there is always dust in the air.  If it is taking a long time to dry either because of humidity, or low temperature, more of the dust can collect. 

   It doesn't sound like its the problem but using a tack cloth isn't such a good idea, a damp cloth is better.  Tack rags generally are oily with substances that waterborne finishes don't like. 

1. 
   OldSaw | May 25, 2006 08:17am | #2

   The shop is a nice 70 degrees (gotta love CA weather) and about 50% humidity.  After 2 hours, the finish is plenty dry. 

   My "finish room":  I cleaned up the shop, swept, vacuumed, and ran the Delta air filter.  Then I built what amounts to a plastic tent over a workbench.  Create a frame 2' x 4', laid the plastic over it, hanging down on all sides.  then I raised the frame up over the bench.  The effect is similar to being underneath a table with a table cloth.

   I'll try adding a bit of water from the fridge filter (warmed to room temp, of course).  The fourth coat seems to be a little better, but I've got a lot of this to do still.

   Thanks.  "Honey, will you please make some sawdust and track it across the carpet?"

   "Yes, dear..."

2. 
   TrueGentleman | May 25, 2006 08:48am | #3

   It sounds as if you need to thin the finish.  The can it came in should tell you what the thinner is and solvent is.  Add the thinner to your finish.  Adding 1 to 10 is a good way to start.  You will need to sand out the bubbles and dust.  Be careful when sanding! You do not want to sand too hard.  Just a light sanding to remove the bumps.   So, sand first, then thin varnish and apply. 

    

   In addition, a sponge is not really the best tool to apply varnish.  Try a varnish brush. This Brush is good http://www.amazon.com/gp/product/B000FPAOIS/ref=pd_rvi_gw_1/103-4344129-2712650?%5Fencoding=UTF8&v=glance&n=228013.  

    

   The key really is that the brush be Tipped and flagged.  You can get one at a good hardware store.  Also, buy the solvent that Varathane has listed on the can.  You will need it to clean the Brush

    

   Good Luck :)

   Rich

    

1. 
   BigK | May 25, 2006 12:04pm | #4

   Another thought that has worked for me on a small piece finished with varathane. Actually it is how I finish a poly finish also. After lightly scuffing the last brushed coat and tacking with a wet rag (NOT a tack cloth), I did a final coat using Old Masters Wiping Varnish, a gelled wiping poly. The completely dried varathane will not react with the oil poly, and wiping varnish leaves a perfect top coat. Smooth as a babies butt. I get mine at the local True Value hardware store. Let me know what you think.

2. 
   jblogan | May 27, 2006 08:50am | #5

   Hey, I checked out the brushes on your link hoping it would explain tipped & flagged. No luck, so my ignorance shows. This is the first time I've heard the term.
   Thanks, Jerry

1. 
   TrueGentleman | May 27, 2006 09:00am | #6

   Tipped just means the brush is thick at the top then tapers to the tip of the brush.  Flagged means the bristles are frayed at the tip.  This allows the varnish (polyurethane) to spread smoothly and reduce brush marks.  Together, they improves your ability to get a flat smooth surface. 

    

   Rich

    

1. 
   jblogan | May 27, 2006 09:16am | #7

   Hey, thanks again. I'll give it a whirl.
   Jerry"I tried to think of that but I couldn't"

3. 
   treeguy | May 27, 2006 03:03pm | #8

   I am no way near an expert in finishing, but I recently talked to a guy who is a very good painter and i asked him a similiar question about the bubbles in the poly.  He said to sand it using wet/dry sandpaper start high (like 600-1000) and work your way down until the bubbles disappear.  If 600 gets rid of the bubbles stop sanding at that grit and don't go any lower, be careful. 

    Also while mixing the poly DO NOT go up and down.  Stick the stirrer in to the bottom and slowly mix until the two parts and mixed fully.  Also tapping the side of the can, will get some bubbles out. 

   He also said foam brushes are the worst thing for poly because they make alot of bubbles due to their construction.  Also use the best brush you are willing to buy the brush really makes a difference. 

   And the hardest part, take your time, this is my biggest problem . 

   Good Luck

   Steve

1. 
   OldSaw | May 27, 2006 07:25pm | #9

   Thanks to all for their suggestions.  I just did the finishing on the next round of sub-assemblies.  I diluted the poly by 10% with some filtered water, and I also sanded between every coat, not just between coats 3 & 4.  That seems to have done the trick.  I'm still using the foam brushes, and that doesn't seem to be a problem.  I think the slightly thinner poly has a better chance to spread out once it hits the surface.

   Thanks for the help.

   -DJS"Honey, will you please make some sawdust and track it across the carpet?"

   "Yes, dear..."