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Damienol
10th June 2015, 08:47 PM
Hi WWF,

i just oust finished building, staining and clear coating our new trestle table for our deck.

349613
As the table was so large it took me about 20 mins to paint the top. As a result you can see brush marks between the sections I started on and the sections I finished. There is 2 coats of clear top on.

i was wondering if anyone knew of a way I could remove the brush marks?

Xanthorrhoeas
11th June 2015, 11:50 AM
The only way that I know is to wait until it is set very hard then sand it smooth, preferably without going right through the existing coats, then re-coat with a very fine wide brush. If you sand before the finish is very hard you will get a nasty mess as the sanding pulls lumps out of the thicker sections of varnish.

If you can get a helper you could start from each end and finish in the middle. Then "dry brush" over the whole surface before it sets to ensure it is quite smooth all over. If no helper is available you have to keep a "wet edge" at all times and move very quickly. Since the temperatures are lower now you should have longer working time for the finish.

Now, if you had used shellac you could just refresh your rubber and work over the surface until it was perfect!

Hope this helps

David

Wood Collector
11th June 2015, 05:21 PM
You could try using a deck oiling mop to apply the finish if you choose to sand it back.

Damienol
11th June 2015, 08:07 PM
The only way that I know is to wait until it is set very hard then sand it smooth, preferably without going right through the existing coats, then re-coat with a very fine wide brush.

David

Thanks for the input David.

by smooth do you mean light sand with a 240 grit or something else?

Damienol
11th June 2015, 08:12 PM
You could try using a deck oiling mop to apply the finish if you choose to sand it back.


Thanks WC however it is not enough of a concern for me to go down this path

Arron
11th June 2015, 08:22 PM
You haven't indicated what the 'clear' you finished it with was, so its a bit hard to comment.

If its what most people call a 'varnish' (generally polyurethane resin in either a water or oil base) then faults are hard to repair. That's because the multiple coats do not meld with each other, and if you sand through one coat into another then you will get a watermark where you have cut through the top coat.

As the other posters have indicated, you can try sanding the affected area. OK if you don't cut through the top coat. Try anything from 400 to 1200 grit, 240 will cut too quickly.

Personally, if the table was important to me, I'd just sand it all off back to bare timber and start again. Often much quicker in the long run.

Anyway, it sounds like your problem is lap marks, not brush marks. To avoid both in future, use a bit of Penetrol in the varnish. It will stop the edge drying, flatten out brush marks, and slow the whole thing down so you can concentrate on quality of job, not racing the product.

cheers
Arron

Damienol
11th June 2015, 08:32 PM
You haven't indicated what the 'clear' you finished it with was, so its a bit hard to comment.

If its what most people call a 'varnish' (generally polyurethane resin in either a water or oil base) then faults are hard to repair. That's because the multiple coats do not meld with each other, and if you sand through one coat into another then you will get a watermark where you have cut through the top coat.

As the other posters have indicated, you can try sanding the affected area. OK if you don't cut through the top coat. Try anything from 400 to 1200 grit, 240 will cut too quickly.

Personally, if the table was important to me, I'd just sand it all off back to bare timber and start again. Often much quicker in the long run.

Anyway, it sounds like your problem is lap marks, not brush marks. To avoid both in future, use a bit of Penetrol in the varnish. It will stop the edge drying, flatten out brush marks, and slow the whole thing down so you can concentrate on quality of job, not racing the product.

cheers
Arron


Thanks Arron,

i think ink you are right about the lap marks. The clear I used is a Urethane - see pic.

i thought about using some 400 on my ROS however I have not been able to find anything finer then 240.

if I just work on the affected areas and apply the clear again will that not just exacerbate the problem?

Arron
11th June 2015, 09:30 PM
if I just work on the affected areas and apply the clear again will that not just exacerbate the problem?

Possibly, as I said fixing poly and urethane varnishes is difficult. They are not made for that.

What I would do is allow a couple of weeks for it to fully harden, then with 400 grit rub over the affected area removing any unevenness to the hand but being careful not to cut through the top coat. If you do, you will get one of those squigly watermarks, which will be diminished when you put the next coat on but never fully disappear. Then I'd recoat the whole top, but putting some Penetrol in the mix (after checking its compatible, of course) so you dont get brush or lap marks.

I always use 400 as my grit between coats and have never had a problem. I use 1200 after the job is finished and I just want to buff up without tearing at the surface.

That would be my second best option. Best option I've already mentioned - that table looks too finer job to not be worth sanding the top back to bare and doing again.

Cheers
Arron

Arron
11th June 2015, 09:56 PM
Oops. Just reread my post and realised I said penetrol when I meant flowtrol ( floetrol ??). Anyway, the maker of both products is Flood and they are pretty helpful.
Cheers
Arron

ubeaut
15th June 2015, 02:18 AM
As Arron said.

Also... Make sure you have a really good brush that's designed to work with the finish you are using and not a $5 one from Bunnies or K Mart, etc. Go to a proper paint shop and ask for their help in getting the right brush for the product and the job. Just because a brush is wide doesn't mean it is the right one for the job at hand. Most are made for paint not for varnish or clear finishes.

If the sales person in the shop hesitates or scratches their head, walk away and try another. There are plenty of them and with luck you'll find one staffed by people who know what they're talking about.

Oh yeah, and next time buy good quality Australian product..... Sarcasm, sorry. :B

Cheers - Neil :U