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Problems with spar urethane

16K views 12 replies 7 participants last post by  jgrickett51  
I just finished varnishing a pair of exterior doors with Minwax Satin Helmsman and it turned out beautifully. I'm not sure what caused your problem but here's a couple of things I did between EVERY coat:
  • made sure I thoroughly stirred the varnish before each coat.
  • I thinned the first coat approx. 25% and each subsequent coat 10%
  • I lightly sanded between each coat. I was able to put 2 coats per day on with about 12 hrs between coats.
  • After sanding I wiped it down with mineral spirits and let that flash off.
  • I put 5 coats on the interior surface and 7 on the exterior.
  • I had a couple of questions before starting my project and called their support number. You may want to run your problem by them.
Here's a couple of pics -
View attachment 427522 View attachment 427523
Beautiful doors! Thank you for the “tutorial.”