Gloss finish and modern brushes

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For a number of years I have had moderate success getting a good finish on gloss paint and varnish work.

This winter I have been painting the headlining boards, in my garage, with white gloss. As it is a fair area to cover I treated my self to a new paintbrush from our local hardware shop. It is a "Harris" brush, 1 1/2 inch, general purpose with synthetic bristles, of mid range quality.

Try as I might I could not get a good finish, however carefully I tipped off I ended up with a load of tiny air bubbles in the finish. I have blamed every thing, its too cold, its too damp etc. Thought I would try a different brush so went to a large national chain of diy stores and bought a brush specificaly for high gloss finishes (the most expensive one avaliable), it also has synthetic bristles. All the brushes had synthetic bristles. No improvement.

Last night I had had enough and dug out an old paint brush with natural bristles as a last resort. Perfect finish! Well, to my standard anyway.

Is it me or has anyone else found the same and I am right to blame my tools?

Stuart
 
I find that odd.What paint are you using?Are the panels already painted or bare?Those Harris brushes are very good and anyway I can't see how they would mix air with the paint.Do you squeze the excess paint off?Since you've been successful in the past it can' be down to your technique.
I had that happen once when varnishing sole boards that had been scraped clean.The varnish was a very quick drying single component floor type and I could see the bubbles coming out of the grain and getting trapped in the varnish as it hardened.
 
status said:
For a number of years I have had moderate success getting a good finish on gloss paint and varnish work.

This winter I have been painting the headlining boards, in my garage, with white gloss. As it is a fair area to cover I treated my self to a new paintbrush from our local hardware shop. It is a "Harris" brush, 1 1/2 inch, general purpose with synthetic bristles, of mid range quality.

Try as I might I could not get a good finish, however carefully I tipped off I ended up with a load of tiny air bubbles in the finish. I have blamed every thing, its too cold, its too damp etc. Thought I would try a different brush so went to a large national chain of diy stores and bought a brush specificaly for high gloss finishes (the most expensive one avaliable), it also has synthetic bristles. All the brushes had synthetic bristles. No improvement.

Last night I had had enough and dug out an old paint brush with natural bristles as a last resort. Perfect finish! Well, to my standard anyway.

Is it me or has anyone else found the same and I am right to blame my tools?

Stuart
Click to expand...

I suggest two possibilities, the second more likely:
1) low temperature.
2) presence of dust in the brush.

You might be surprised on how difficult is to get rid of fine dust on the bristles of
a brush. Just watch carefully while you rub a "perfectly clean" brush in direct sunlight.

Then, of course, the dust may come directly from the substrate to be varnished.

Daniel
 
The panels were bare, having removed Westerlys beloved lining vinyl and the remanant glue, then primed and undercoated.

Have just had a look at Harris' website and they recomend the classic for varnish and gloss, which is a 100% natural bristle brush.
 
I've never had success with a modern synthetic brush, bristle gives a much better finish - the best brushes have springy bristles and retain their shape when wet.

Bubbles are likely to be from overworking the paint, especially modern thixtropic (non-drip) types.

For solvent based paints I now use the cheapest bristle brushes that I can find (within reason) and treat them as disposable. Saves a fortune on brush cleaner, although it does mean having to spend a bit of time removing shed bristles.
 
status said:
For a number of years I have had moderate success getting a good finish on gloss paint and varnish work.

This winter I have been painting the headlining boards, in my garage, with white gloss. As it is a fair area to cover I treated my self to a new paintbrush from our local hardware shop. It is a "Harris" brush, 1 1/2 inch, general purpose with synthetic bristles, of mid range quality.

Try as I might I could not get a good finish, however carefully I tipped off I ended up with a load of tiny air bubbles in the finish. I have blamed every thing, its too cold, its too damp etc. Thought I would try a different brush so went to a large national chain of diy stores and bought a brush specificaly for high gloss finishes (the most expensive one avaliable), it also has synthetic bristles. All the brushes had synthetic bristles. No improvement.

Last night I had had enough and dug out an old paint brush with natural bristles as a last resort. Perfect finish! Well, to my standard anyway.

Is it me or has anyone else found the same and I am right to blame my tools?

Stuart
Click to expand...
I have had similar poor finish problems with the Harris "no-loss" black bristled brushes. Of the synthetic ones the fine cream/white bristled kind seem fairly good, usually sold in packs of five of various sizes, not that expensive.
 
I was looking for varnish brushes this weekend.. seems like the synthetic bristles are designed for water based paints/varnishes and the natural ones are better for solvent based paints/varnishes.

Since I bought some Ronseal Diamond Hard water based varnish I went for the synthetic Harris brush (although it doesn't feel as good as the synthetic Harris brushes from ten years ago).

I have yet to try it. Perhaps if your paint was solvent based the old (or new) bristle brush might have been the best way to go anyway.
 
It's only one view but from the Dulux (Canada) website....
http://www.dulux.ca/en/equipment-supplies/brushes.html

Quote..
Natural bristles are made of boar hair. Because they are resistant to thinners, they are recommended for solvent-based coatings and varnishes. However, they are not recommended for water-based coatings as they absorb water, swell, and lose their elasticity. Synthetic bristles are better suited for water-based coatings as they absorb less water than natural bristles do.
 
An 'old boy' told me some time ago(I'm the old boy now !!) that you should 'run in' a new paint brush before dipping it into it's first paint.Do this by 'painting' a wall or roughish surface with the brush dry.His theory was/is that painting dry wears the ends of the bristles into a more tapered shape, and thus gives better results.This was also His thoery as to why you get a better result with an older brush.It also removes loose bristles.
Hope this helps.
Cheers
 
Split Ends

I used to regard the views of those who treasured a paint brush for years as a form of miserliness. However, having found a decent bush with natural bristle embedded in epoxy in a stainless steel ferrule, which I have used for the last 6-7 years for hull painting and nothing else, I now understand. The long white bristles have developed split ends! Perhaps those of you who have had a a partner will long flowing hair will understand. The last 5mm or so of bristle are now so fine that they no longer leave brush marks. I imagine that this is what happens when a brush is "broken in".
 
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It may be that the brush is loaded with too much paint. Perhaps thinner coats will not produce this effect.
Another idea that comes to mind is whether the paint is freshly stirred, and there are bubbles in it that have not been allowed to dissipate.
 
Most of you will know I am not a fan timber on boats, I'd rather be sailing thank you.

However a few months back when doing some glassing on a clients boat and waiting for some epoxy to go tacky the asked if would help him varnish the companionway steps and storm boards.

As above the first thin I noticed was tiny bubbles forming behind each brush stroke, I a think about what might be causing this and decided to rum my hot air gun over it.

All bubbles vanished and no more showed up, the finish was quite good too. I have no idea what sort or type of varnish it was, but had a low level smell if that helps.

.
 
No expert in this field but I usually set my paint or varnish pot in an old saucepan of hot water, not boiling, and allow to stand for a minute or two; this thins the consistency of the paint which goes on without brush strokes showing, and in the case of varnish helps the absorption into bare wood without further thinning.
Any time I have had bubbles appearing it has been on bare wood and usually a primer coat applied too cold.
I also used Owatrol to help the flow and finish lines in paint but never tried it with varnish, paint was OK though.

ianat182
 
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