Varnishing basics

[dmede]

When I varnish my canoe, no matter how hard I try, no matter how lightly I think I'm loading my brush, I get runs. They seem to magically appear after I’ve double checked every part I just varnished.

In my case I have been using McCloskys Man-O-War spar varnish (semi gloss). I think I may have thinned my first coat but all subsequent coats went on full strength. I use 2" JEN foam brushes. While I have gotten a lot better, its still very frustrating at times and I know I'm missing some basic techniques.

For someone who doesn't need a perfect job but wants a good looking work boat job, what are the most basic principles of varnishing? Please keep it simple, if you can, I know there’s a lot of personal techniques and some very advanced methods out there, but for me I just need the basic stuff, like how much to thin, if at all, etc.

Thanks,
dave

[pcford]

Use a foam brush. It's harder to put too much on. Don't worry about holidays. Err on the side of too light.

When you gain confidence, you may wish to switch to a high quality brush.

McCloskeys is a fine varnish, though it is thin compared to others.

Oh, you should use satin or semigloss for the last coat only. Use gloss in your build coats. The flattening agents obscure the clarity of varnish.

[Scott Rosen]

Foam brushes are hard to use on large surfaces, like a canoe hull. Even someone expert at using foam brushes would find a 2" brush to be way too small for your job.

Try getting a decent 3" or 4" china bristle brush. You can find them at any paint store. Then brush the varnish out really well.

[marsbar]

Dave, your story sounds just like what I experience with varnish. I have found at least for me, rolling on a thin layer of varnish with a small foam roller, then immediately tipping it off with a brush of your choice, minimizes the runs. I tip off as soon as the rolled on varnish is applied, and I apply it VERY thin. Doesn't seem to matter the direction of the rolling, just get it on fast. Hope this helps, it seems to work for me....Mark

[Richard Smith]

Listen to pc.

I used to be a really cr*ppy painter/varnisher . . . until I discovered Zen painting! Then, I started to see the "light." You must "get your mind right." (Cool Hand Luke) The solution to sags is, "Think holiday" - at least for a while. Say, "I will leave holidays," over and over. Now, visualize the holidays . . .

Also, thin the first few coats - and leave holidays for all. Visualize the coats melting together as a unified whole of many, happy, holiday filled coats to produce the finish that you always wanted.

Works for me, and I have the photos to prove it.

Oh yeah, almost forgot . . . beer helps.

[chergui]

There was another recent posting somewhat related ("epifanes vs interlux schooner") to this. The first time I varnished I had lots of sags. It was quite awful. Each time I'm getting a bit better like you say. Actually I was varnishing this weekend. Here's what I do. I use a good badger bristle brush and have two containers, one with my varnish, another to get rid of the excess after dipping it in the first container. This prevents bubbles accumulating in the "source" container and prevents loading the brush up with too much varnish. You don't want the brush dripping, it will be impossible to apply it thin enough. Then right after applying the varnish to a small section, if I think it's too thick, I brush it out with a foam brush. If it flows through the varnish then it can maybe be a bit thinner. If it skips then it's thin enough, maybe too thin. After doing a section, look at it in the light from different angles to make sure you haven't made it too thin, you may see little patches that look dull. If so, go back over them (quickly before it starts to cure, esp. when it's hot out). When applying the varnish, I usually keep brushing out a section until it seems a bit thick and the brush doesn't run through the varnish quite as easily as when first applied. But do it slowly otherwise you get bubbles. One thing I've found is, take your time, pay attention, and there are no shortcuts to get it done faster. I find now that I don't have to brush it out with a second brush very often, I can usually tell when it's thick enough. I find if I do the above I can usually get it right. It's all very finnicky. I swear people thought I was crazy paying so much attention and inspecting it so carefully. Also, it seems easier if the surface is cooler, to me anyway so do the sections in the shade first or better still do it when it's cloudy out.

[pcford]

I used to be a really cr*ppy painter/varnisher . . . until I discovered Zen painting! There really is something to that. It takes a lot of concentration....or if it's Zen does that mean it requires a lack of concentration?

Uhhh, however, I don't think beer increases concentration. At least not with me.

I don't drink at work. And have all my fingers to prove it.

[pcford]

I glossed over the original poster's comment that he was using a 2" foam brush. I agree that this is too narrow. Now, bristle brushes are no doubt better, but I often advise newbys to use foam brushes until they get the hang of things.

Oh, just buy 3" foam brushes. The 4" get floppy quickly. If you want a narrower brush just cut it with scissors.

[dmede]

I should have said I use an assortment of foam brushes (1" 2" & 3"). It depends on the surface I'm varnishing. My first canoe is lapstreak ply with lots of narrow planks and other small surfaces so the 2" gets used most. I find that the 3" just casues me to squeeze out varnish over the edges of the planks causing more drips and lots of swearing.

The new canoe is solid western red cedar and has only three rather largish planks per side so maybe the 3" will work better here.

I take it I should deffinetly not thin Man-O-War since its already thinner than most? Or will I benefit from applying the first coat with thined out varnish? The WRC is very thirsty if that matters.

I'm not going to buy any expensive brushes, my varnish jobs don't warrent them yet. So is foam better than a mediocre brush?

[pcford]

I'm not going to buy any expensive brushes, my varnish jobs don't warrent them yet. So is foam better than a mediocre brush? The point I am trying to make is that foam brushes put on a skimpy coat. In this case, that is a GOOD thing.

In terms of thinning the varnish, follow the instructions on the can. McCloskey's varnish is thinner in comparison to other varnishes, but I am sure they still want you to thin it.

[dmede]

actually they say "Do not thin"

but I do lots of stuff I'm not supposed to :D

So the key, rather intuitively, is to keep each coat very thin? I think I understood that thin is better but Ive been trying to get it thin while still getting full coverege with every coat, i.e. no holidays.

[pcford]

Like I've been struggling to say...do NOT worry about holidays for a few more coats. Actually, a perfect coat without holidays is only necessary for the final coat.

[dmede]

thanks pcford, sorry to be painfully repetitive in my questions. your replys have been very clear, I just like to restate my thinking on a point to be sure I'm not misunderstanding at all.

Ive only got the 4 deck boards and a coaming to put in then it'll be time to go ahead and finish. I'll save these notes till then and hopefully see some improvment.

dave

[JimConlin]

For larger areas like a canoe or a whole dinghy, i use foam rollers (the 1" dia. x 6" kind) and tip out with a foam brush. I find that the rollers give much better control over the amount laid down.

[Richard Smith]

I take it a step further and use a "foam roller brush" (as shown at http://www.westsystem.com/ > Using West System Epoxy > User Manual > Epoxy barrier coating) to tip off with. Also, check this book out by Rebecca Wittman > The Brightwork Companion (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=4562764459&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1). She advocates the use of foam brushes.