View Full Version : Varnish foam... can it be fixed?

Li'l Brown
09-02-2007, 05:42 PM
Hi all,

I've just varnished a painting with Golden Satin varnish and much to my dismay the brush or the varnish or my own ineptitude or a combination of all three has left streaks of foam that show white against the black background. Is there anything that can be done to fix this? Will it fade with time- the varnish is dry to the touch.

I would really appreciate your assistance on this one.


Li'l Brown
09-02-2007, 06:11 PM
Here's a couple of pics to show you what I mean:




09-02-2007, 09:49 PM
Sorry Jess, I dont know..but I feel your pain:crying:

09-03-2007, 09:28 AM
Jesslyn, I can't offer any help at all. I have had this happen to me too and I get brush marks too which upset me. I must be awfully heavy handed with the brush. I did a search of the forum for "cloudy varnish" and this thread was informative: http://www.wetcanvas.com/forums/showthread.php?t=373574&highlight=cloudy+varnish

and another link: http://www.wetcanvas.com/forums/showthread.php?t=188254&highlight=cloudy+varnish

I can understand now why it is important to have an isolation coat of medium, thoroughly dry, before applying varnish.

Hope this helps some.

Li'l Brown
09-03-2007, 10:48 AM
Thanks for the link Ann, and Doc for the commiseration :)

I had never heard of the isolation coat before and after reading all the info on varnish from the Golden site I see I should have done some research before I started- may have helped some. Oh well, lesson learned and maybe someone else will benefit from my mistakes.

Not a total loss... I just have to keep the painting out of direct light and you can't really see the streaks at all.

FYI, here is the info sheet on Golden's polymer varnish: http://www.goldenpaints.com/technicaldata/polvar.php

09-03-2007, 11:24 AM
You could try a solvent to remove
I use a product called F 10 Clear coat...It is tough stuff and gives a sheen to acrylics that is really nive..water proff, doesnt yellow and protects from UV rays
use mineral spirits to clean brushes and to thin the F 10 before applying

you could also lightly sand the existing stuff then apply the f 10

get it at a hardware store..


09-03-2007, 11:25 AM
Excuse the typos..was in a hurry


pero lane
09-03-2007, 12:09 PM
Try using one of those foam applicator brushes available anywhere (home)paint is sold...it gives you a nice smooth even finish...only cost about .25 each. :)

Li'l Brown
09-03-2007, 02:47 PM
Hey, DrJim, thanks for the tip! And Pat, I found one of those little brushes just after the foam debacle-- too late, naturally, but good for next time.

I now know I also did a few other things wrong:
- didn't check out Golden's site to get the application tips -- yes, they really ARE important!!!
- used the wrong type of brush
- varnished outside in the sun- the varnish dried too quickly

I've sent in my problem to Golden's tech support in hopes they may have a solution or suggestions on how to improve the appearance. Figured it couldn't hurt.

Li'l Brown
09-04-2007, 06:52 PM
FYI, here is the response I received from Michael Townsend, technical support at Golden.

The completed artwork should be sealed with an isolation coat of acrylic medium. This helps to seal the absorbency of the surface, which in turn allows the varnish to go on more evenly, and also seals the surface of the paint film to reduce the chance of color loss during varnish application or removal.
The 4:1 ratio of Polymer Varnish to water is a good starting ratio, so this could remain the same.
Because the varnish does dry so quickly, it's important to try to give yourself as much time to apply the varnish evenly before the varnish layer begins to dry. Once the varnish begins to dry, it is not uncommon to have brush strokes and air bubbles dry into the varnish film. Try to apply the varnish out of direct sunlight, in a relatively cool, somewhat humid environment, and also avoid too much air movement during the varnish application. Once the varnish layer is dry to the touch (generally 2 or more hours), then the work can be exposed to more aggressive means of drying, if necessary.
The proper Brush for varnishing is important, and one should always try to use a brush which is wide, flat and thin to give the best control of applying a thin varnish film, but do not discount proper technique. However, please read Introduction to Varnishing http://www.goldenpaints.com/technicaldata/varnapp.php and Varnishing Application Guidelines http://www.goldenpaints.com/technicaldata/varnapp1.php to help with these concerns.
Proper technique is really important. Aside from the info in the above link, realize when varnishing it's important to have control of the varnish, applying an even coat of material and giving it as long as practical to even out before it dries. Put the product on the surface, and then leave it alone to cure. The more one tries to brush out imperfections, or pop a bubble, the more likely the work will retain brush marks, bubbles and finger marks.
It is possible that some minor foam and brush strokes can be corrected with another coat of varnish because the varnish is resoluble and another coat can improve the overall evenness of the varnish film. However, with so many things being done incorrectly on this piece, the likihood another coat applied will take care of the problems.
Realize practice with these products is very important. The work is generally better of unvarnished until you have a better handle on the process, so take your time getting used to the product on paintings you don't care too much about.
Also, the best suggestion for fixing the artwork at hand is to do the varnish removal process, which although seems tedious, is pretty straightforward and the best chance to get the painting back to it's original look. Please review the removal instructions in the Polymer Varnish Information Sheet http://www.goldenpaints.com/technicaldata/polvar.php. The varnish removal process should be able to remove the uneven varnish coats in about 5 minutes if done correctly.

Hurray, all is not lost! I'll let you know how it goes.

09-04-2007, 07:35 PM
While I haven't used them, you might try an aerosol spray varnish next time--Windsor & Newton, and Grumbacher, make a varnish for oil/acrylic paintings that comes in a spray can. I would guess this would eliminate brushstroke problems; you'd just have to do it outside/in the garage, etc.

09-04-2007, 07:47 PM
Jesslyn, thanks for posting all that info! I hadn't replied to your post as I didn't have the answer for you but really appreciate the info, I need it too. Good luck to you, looking forward to hearing how it goes (hopefully it goes fast and well!)

09-05-2007, 01:34 AM
Hi Jesslyn:)
This has happened to me as ell.I gave it another thin coat and they all disappeared:) Give it a shot girl.Waddya got to lose,eh? But I think you'll be happy!!

09-05-2007, 03:22 AM
How complicated
It looks to me like you may have had some moisture on the brush?
I think the previous bit of advise was probably the best.
Revarnish it and the streaks should disappear.

I spray varnish as a preference.

My best advice is do not be in such a hurry to varnish anything. Leave the work for as long as 6 months or more depending on the thickness of paint applied. Some oils are hydroscopic believe it or not.

09-06-2007, 12:39 AM
So???? Did you try going over it again???

Li'l Brown
09-06-2007, 08:10 AM
Hey Tony,
The thing is, there is already more than one coat on there, as I, in a bit of a panic, had slapped a second coat on immediately to try and eliminate the bubbles. The same thing happened with the second coat, so I'm guessing I'll have to try to remove the varnish and hope I don't really ruin it this time. But maybe it could not hurt to try again with the right kind of brush and in the right environment... and then remove if necessary. Maybe tonight.

Li'l Brown
03-01-2009, 10:14 PM
I am dragging this up from the depths bc someone has just posted a varnishing question and maybe the info here could help.

I never did post my followup to all this. Revarnishing did not help. I followed Golden's varnish removal process using a diluted ammonia -- click the link earlier in this thread for exact instructions -- and an old ripped up cotton t-shirt (try for something with as little lint as possible) and it worked like a charm. I had not even used the isolation coat and the removal did not affect the paint. I DID NOT WIPE the varnish off the painting, I laid the cloth over the painting and let the solvent do its work. When I lifted the cloth, the varnish came off too.

I then carefully revarnished my painting following Golden's instructions and it went very well.

Just a lil FYI!