Removing spar urethane

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I recently redid a table using spar urethane and due to the thickness of this product it didn't coat the table evenly. So, I tried sanding it down and I cannot get the finish to come off so I can reapply stain and use a water based polyurethane.
I now have white streaks throughout the table. Am I going to have to use a chemical stripper to remove this finish completely off the table? It seems to be my last ditch effort
removing spar urethane, painted furniture, woodworking projects
  13 answers
  • Z Z on Sep 15, 2014
    Attn: Kevin, (@KMS Woodworks), could you please help my friend Monica with this problem.

  • Monica33flowers Monica33flowers on Sep 15, 2014
    Thank you so much @Z

  • If the varnish was recently applied it will be to soft for many weeks until it drys all the way through. This prevents sanding to be successful. As it will only gum up the paper. Check on the can of the material you purchased as they will have a list of chemicals that will clean this off. If that does not work you need to wait for several weeks to it dries hard enough to sand or use paint stripper and start all over again.

    • Monica33flowers Monica33flowers on Sep 16, 2014
      @Woodbridge Environmental Tiptophouse.com Thank you so much for your help. I think I should add that this table was purchased at a store 3 or more years ago (I think it was probably 5). The finish was guaranteed for 2 years. So, much of the finish was gone in spots and also very dull. So, I originally sanded it completely down. It was a difficult task because when I started sanding it was gumming up. I used a deglosser per my local hardware store. That didn't help...it was just a lot of sanding and using a putty knife to remove the stubborn spots. Then I stained it and added the spar urethane. I called the manufacturer of this product right away because of the difficulty I was having getting a nice even coat. I did all the steps per the manufacturers advice over the phone and it still looks terrible even though you can't see it that well in this picture (it was the best one I had). So, when I did the last sanding I used 80 grit sandpaper and the finish wouldn't budge...I went down to 50 (used 5 pads) and then I was able to get the "high spots" out but it didn't gum up at all...the finish is solid. I am just so frustrated at this point and when I called customer support again last night I didn't get what "I feel" is the right answer....using a deglosser again. There has to be some way to remove this and start over....I am at the point of breaking...this truly has been such a nightmare.

  • Monica33flowers Monica33flowers on Sep 16, 2014
    I think I should add that this table was purchased at a store 3 or more years ago (I think it was probably 5). The finish was guaranteed for 2 years. So, much of the finish was gone in spots and also very dull. So, I originally sanded it completely down. It was a difficult task because when I started sanding it was gumming up. I used a deglosser per my local hardware store. That didn't help...it was just a lot of sanding and using a putty knife to remove the stubborn spots. Then I stained it and added the spar urethane. I called the manufacturer of this product right away because of the difficulty I was having getting a nice even coat. I did all the steps per the manufacturers advice over the phone and it still looks terrible even though you can't see it that well in this picture (it was the best one I had).So, when I did the last sanding I used 80 grit sandpaper and the finish wouldn't budge...I went down to 50 (used 5 pads) and then I was able to get the "high spots" out but it didn't gum up at all...the finish is solid.I am just so frustrated at this point and when I called customer support again last night I didn't get what "I feel" is the right answer....using a deglosser again.There has to be some way to remove this and start over....I am at the point of breaking...this truly has been such a nightmare.

    • @Monica33flowers You need to completely strip the piece with a chemical stripper. Deglosser is used for getting into those tiny areas that sand paper cannot. It also is used on pieces that have designs or impressions that would be sanded away. Its not supposed to be used to sand a solid piece that sand paper would work as well. Once the piece is stripped sand the wood down using fine sand paper until its really smooth. Then seal, stain, and poly or varnish the surface according to the manufactures directions. Be sure to use the same brand system all the way through the project. There could have been a chemical reaction to what you used on top of the older material. Although doubtful, you never know.

  • Monica33flowers Monica33flowers on Sep 16, 2014
    Thank you, Woodbridge! I used all Minwax previously along with a Purdy brush. Do you have any favorite products that are very durable? This piece is also oak and I was wondering if you have any suggestions for a sealer. Thanks again!

    • See 1 previous
    • Monica33flowers Monica33flowers on Sep 17, 2014
      @Woodbridge Environmental Tiptophouse.com the weather was in the 80's and no humidity. But it was humid when I applied the urethane. When I applied the urethane with my Purdy brush I put on very light coat and the brush was becoming all gummed up. I did let that coat sit for about 4 days before I lightly sanded and added the next coat. Again, very nice weather and the urethane was very thick. I called the company service rep and they said I could use 10% mineral spirits to thin out the product. I mixed up the mixture in a separate container so I was sure not to add it to the original can. That didn't help smooth out the urethane. Then I called again and the rep said that I had to use "Pure" mineral spirits and not "odorless". That is what they said was the problem. This past weekend I opened the can of urethane and it had become somewhat solified. Nothing was ever added to the original can and the lid was always put on using my soft hammer to insure that it was sealed and never left open unless I was using the product. I had a very clean brush every time I did an application. I wanted to protect this brush the correct way.

  • Monica33flowers Monica33flowers on Sep 16, 2014
    I need a clarification about a response

  • Z Z on Sep 16, 2014
    The only thing I might add is the top of the table could very well be veneer so you have to be very careful not to sand through that.

  • Monica33flowers Monica33flowers on Sep 16, 2014
    Hi Becky! It is solid oak...no veneer at all and it is heavy. Uff da.....

  • Monica33flowers Monica33flowers on Sep 16, 2014
    Thanks for the answers, but I'm still hoping for more ideas.

  • Monica33flowers Monica33flowers on Sep 17, 2014
    What type of sealer do I use prior to doing the stain @Woodbridge Environmental Tiptophouse.com

  • Its a sealer that will prevent the stain from soaking in unevenly. As there are softer and harder spots on the top some will soak the color of the stain at a faster rate then other spots which will give the appearance of a blotchy finish. Here is a link that tells you about the different types available from Minwax They also show a stain remover that they carry. http://www.minwax.com/wood-products/preparation/

    • Z Z on Mar 17, 2015
      @Bob, thank you so much for helping my dear friend Monica. She really did appreciate it. She finished the table and the friend she was doing it for was very happy with it. Monica passed away last Wednesday. I've been going through our private messages on fb to feel close to her and found her link to this post. She was the sweetest kindest person and was so thankful for your help.

  • Monica33flowers Monica33flowers on Sep 17, 2014
    @Woodbridge Environmental Tiptophouse.com Thank you so much! I found the sealer that I will need. I really appreciate all your help! Thanks again!

  • Christy Minnich Christy Minnich on Sep 25, 2015
    @Monica33flowers how did you get the spar urethan off? Ground hog day here a year later I am in the same situation as you practically to the T same time year, temperature, comments from minwax... Not sure why Big Box stores even sell the spar if it is suppose to be for boats etc...and not really indoor at all from what I have since found out. I have had horrible trouble with my table refinish and now I have 2 light full strength coats of spar on and I need to get them off.