tiny bubbles ruining the finish of all my varnish

firstascent2002

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why is it that every time I varnish with epifanes, in the correct mixtures with the right thinner as appropriate, the surface once dry has a load of tiny tiny bbbles in it. The key sanding for the next coat removes them but after the next coat they are there again. Is the varnish going on too cold and not flowing? I am doing it in my garage!
 
(1) Make sure that the varnish and the work are at the same temperature.
(2) Use a soft brush. Do not dip the brush into the can. Pour out what you need into another container and dip lightly into that.
(3) Do not over-brush; that creates bubbles between the bristles.
(4) If there is a draft across the surface, these bubbles will not be able to flow out before a skin forms.
(5) Thin your varnish (up to 5%) to improve the flow.
 
Could be 'outgassing'. The timber is warming up after application, and air in the timber is being expelled. After you varnish, turn the heater off. No prblems varnishing in this weather, but Epi is very slow to dry. Suggest International Original. Better.
 
Read previous post (mine).

I had the same problem with Sikkens who advised that "something" was coming out of the wood. "Something" could be moisture or possibly resin.

They advise warming the wood to drive out both and maybe even vacuuming the surface to encourage the process.

My reply was that it was a pity they didn't mention this on the tin.
 
Presumably if it was happening on the later coats then it was not bubbles from the wood.

I do notice that using a brush straight out of the white spirit jar gives bubbles. Havn't tested the theory, but do varnish brushes need to be dry, or perhaps genuine turps helps?
 
from epifanes q&a
We will bet that what you are experiencing is dust. Dust and/or lint particles that dry in the varnish can form tiny craters that can certainly look like air bubbles. It is very rare for air to dry in a coat of varnish. Let's try to figure out where this dust might be coming from. If the coat looks great upon completion but several hours’ later looks as if someone has taken a saltshaker to your boat, then the dust problem is most likely airborne. If the dust occurs right away, brushes and the initial cleanliness of the surface are more likely to be the culprits. Here are a few, sometimes overlooked, sources of dust; • Although your brush may appear clean, try flicking the bristles in front of a bright lamp. You will be amazed at what comes out of it. Turn on the TV and be patient. It can take an hour. Do not assume that a new brush is clean, new brushes are particularly dusty. • Be aware of what is happening overhead, it may be that your basement ceiling is shedding dust each time someone crosses the room upstairs. • Fluorescent lights will act as a dust magnet until the moment you turn them off. • Check your clothing. Wear dampened Tyvek coveralls. • Mask or temporarily seal all screw holes. Your brush will certainly pull out whatever is hiding in those holes. We know a painter that varnishes in the nude listening to Vivaldi. Hey, whatever works.


like the others have said, use a good brush and work from a separate container with the required amount of varnish in it.

steve
 
Foam brush recommended. Just finished using Epifanes Rubbed Effect. No bubbles or other prolems. Did it indoors, warmed tin, wiped with white spirit after sanding.
 
I snivelled about this too. Have experienced outgassing but only on early (1st coats). My "bubbles" were, I was persuaded after intense resistance, dust. I now have a poly tent within the workshop and do better in that environment.

I have also realised that once on the boat, blemishes which I could see in the workshop were pretty invisible.

But maybe I'm lax.

Stick with Epifanes is my advice. Good rapid build up of coats, nice lustre, and pretty robust abrasion resistant finish.
 
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