# Spar Urethane Advice!



## brentt03 (Jan 12, 2016)

I am working on a bar top and have used Helmsman Spar Urethane.

I brushed on 2 light coats, sanded after the 2nd coat with 800 grit then added a thick layer by foam brush as my 3rd layer.

Problem is this bar isn't 100% level and i need to get rid of some lines; what do you suggest I do to even all this out.

My plan is that once I get it all smooth and the lines out to add Ultra Clear epoxy for the final coat.

http://www.bestbartopepoxy.com/epoxy/?gclid=Cj0KEQiA5dK0BRCr49qDzILe74UBEiQA_6gA-hsxU1N3kqFCBUPwqmv525l2bfLB7t76OHdEF156tsoaAjIy8P8HAQ

I've marked in the pic where it needs to be worked on, just wondering if i need a lower grit sandpaper, steel wool or what?

Thanks all!


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## TimPa (Jan 27, 2010)

I would block sand with 220, but not aggressively. then apply another coat of spar.

trick with spar is to not overwork it when applying it. it will self level. put it on and let it go. usually we bristle brush spar.

have to watch that in this cold weather tho, all has to be warm.

after some use you will likely not see any lines.


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## Steve Neul (Sep 2, 2011)

You just can't do what you are attempting. You can fix the spar but you can't put epoxy over the top. You also shouldn't put a thick coat on at once. This can cause leveling problems by itself. 

Just so you know a spar varnish is a softer more elastic finished formulated for exterior use. Using a varnish you would have been better off using an interior oil based polyurethane. It's a harder more durable finish for the application you are using it for. Since you already have the spar on I would live with it. When the time comes you need to refinish it then change to poly or epoxy. 

If the end result was an epoxy finish then you should have used a pour on epoxy and been done with it in one application on bare wood. It doesn't do well over another finish. 

Now to fix the spar, assuming you mean by the lines meaning brush marks. 800 grit is just too fine to do any leveling. You would be better off using 180 or 220 grit paper on a hard rubber block or glued to a piece of wood to sand off brush marks. If they are very pronounced you may need to sand it, put another coat on, sand it again and then put the finish coat on. When you brush any varnish use as soft a paint brush as you can find and apply the varnish as thin as possible with as few strokes as possible. If the finish tends to drag as you are applying it you might thin it slightly or add some Flood Penetrol to the varnish to slow down the drying time. This will give more open time so the finish can flow together before it sets.


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## brentt03 (Jan 12, 2016)

Is there a way to remove the spar urethane without ruining the stain job underneath?

thanks for the help guys, this is going to be in my brewery, and I want it to look top notch.

That's why I ordered the epoxy


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## Steve Neul (Sep 2, 2011)

brentt03 said:


> Is there a way to remove the spar urethane without ruining the stain job underneath?
> 
> thanks for the help guys, this is going to be in my brewery, and I want it to look top notch.
> 
> That's why I ordered the epoxy


No, all you can do is take some methylene chloride type paint and varnish remover and completely strip the spar varnish off. This may not be an option if it's cold where you are. Removers just don't at all do well below 70 degrees. It's better if the temperature is in the 80-90 range. You would have to strip it, rinse the residue with a strong solvent like lacquer thinner and allow it to dry. Then sand the wood and re-apply the stain. Then once the stain dries a couple days then you can use the epoxy.


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## brentt03 (Jan 12, 2016)

Great info! one last question and I will quit buggin you all. What is the best way to clean the surface after sanding?


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## Steve Neul (Sep 2, 2011)

brentt03 said:


> Great info! one last question and I will quit buggin you all. What is the best way to clean the surface after sanding?


Ask as many questions as you wish. That is what we are here for. Just wish you had come here and asked before using the spar. That type finish should only be used on something like your front door. 

It depends on where you are as far as cleaning. In the shop where it doesn't matter I just blow the dust off with compressed air and wipe the project with a clean dry cloth. Inside someones house where I'm trying to limit the dust I go over it with a vacuum cleaner with a brush attachment and then follow with a clean cloth. A 100% isn't necessary on bare wood. When you stain the wood and wipe off the excess it will pick up what dust is left.


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## brentt03 (Jan 12, 2016)

Wish I had found you guys sooner to ask as well! Thanks for all the help and info! :thumbsup:



Steve Neul said:


> Ask as many questions as you wish. That is what we are here for. Just wish you had come here and asked before using the spar. That type finish should only be used on something like your front door.
> 
> It depends on where you are as far as cleaning. In the shop where it doesn't matter I just blow the dust off with compressed air and wipe the project with a clean dry cloth. Inside someones house where I'm trying to limit the dust I go over it with a vacuum cleaner with a brush attachment and then follow with a clean cloth. A 100% isn't necessary on bare wood. When you stain the wood and wipe off the excess it will pick up what dust is left.


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## Steve Neul (Sep 2, 2011)

brentt03 said:


> Wish I had found you guys sooner to ask as well! Thanks for all the help and info! :thumbsup:


Ok, now from where we are if you take the urethane off and refinish it don't just start pouring the epoxy on the counter. Epoxy is one of the more tricky finishes and a lot harder to strip off than the spar. Mix up smaller batches and try it out on something else first. You have to be gently stirring it too. Too aggressive stirring gets bubbles in the finish you will have to contend with. I haven't done it myself but you are suppose to pass a torch over the finish to bring the bubbles to the surface. Read as much as you can about applying epoxy before you open a can.


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