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Dennis Millard
18th February 2008, 09:02 AM
Some years ago, I made a vanitory top for the bathroom out of an old hardwood door. It came up quite well and I finished it with a good quality Marine varnish, which was quite satisfactory.
Over the years, however, it began to show signs of wear and tear, so I decided to freshen it up. I cut it back a bit with an orbital sander, (not a lot, just enought to give it a key), and relaid a good coat of the same type of high gloss varnish.
The gloss is excellent, but I found that almost every brush stroke is visible as if I had used a coarse tar brush or something, (which i didn't).
Why didn't it flatten out as is customary on a flat surface? I don't understand it.
Any ideas?

orraloon
18th February 2008, 09:34 AM
While not being an expert I reckon it was too thick and in need of some thinners (turps). A test application on a board and the brush marks should melt away soon after the lay off strokes. If not then more thinners. Be carefull not to add too much, we are talking in a few teaspoons here or sometimes drops. Check the instructions on the can for thinning and use a good quality brush.
To fix it I would sand back a bit ,just to remove the brush marks then another coat.

Regards
John

Honorary Bloke
18th February 2008, 10:47 AM
The gloss is excellent, but I found that almost every brush stroke is visible as if I had used a coarse tar brush or something, (which i didn't).
Why didn't it flatten out as is customary on a flat surface? I don't understand it.
Any ideas?

As said above, the varnish is too thick. Add thinner and re-do it. The more thinner, the easier to apply. Even up to 30% thinner or more is acceptable, but will require more coats. No worries, just adjust your mix and go again. :)

The biggest problem with varnish is the ability to apply it quickly enough to blend it in.

Fencepost2
18th February 2008, 11:21 AM
And in addition to the good advice above, just check that the temperature at the time of application is okay. A very hot day can dry out the varnish before it has had opportunity to flow smoothly. If it is a high 30 degree Celsius day the varnish can be tacky even as it leaves the brush. This is just my observation, I am not an expert, if this is not valid please someone write in and put me right. :)

jerryc
18th February 2008, 05:13 PM
All the above advice is good. Most varnish straight from the can is too thick and as Bob says, can be thinned back considerably, up to thirty per cent is not excessive in the right conditions. But remember temperature and thinners are interrelated. What works in Tasmania's winter is not the same mix you would use in Darwin's summer. My advice is ALWAYS test a finish and/or a mix on a piece of scrap. Better to have a well finished piece of firewood than a b******d up unit that should be your pride and joy.

Jerry

Everyone is entitled to my opinion

MacS
19th February 2008, 06:46 AM
Chances are your over brushing, practice brushing one way - one stroke, it will eleminate having those extra brush streaks, the key is "loading up the brush, and laying down a heavy coat," but doing it evenly throughout the brushing.

It takes some practice, but it will be worth your time.

Harry72
19th February 2008, 08:45 AM
True words MacS
99% of people dont put enough on and then overwork it because its not covering... basically slop it on as thickly as you can get it without runs(watch some pro floor finishers slop it on with mops... thickly as they can get it)
Seeming there is still some old base coating left do not thin it much, its only really needed on the 1st coat. 10% is plenty with high gloss polyU paints.

MacS
19th February 2008, 09:05 AM
Over here, we are not allowed to add solvents into stains or coatings, if you do, the materials will not be in compliance with the law. (VOC)

These matierals are all ready for use, in many cases you may need to make some application adjustments like making temperature adjustments, heating the materials for better flow out, ect.

manoftalent
19th February 2008, 01:17 PM
all good advice and I can only add this .....brush with the grain ...not across it ......and do the job in a cool enviroment ..