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Re: Material: Satin Finish Varnish trouble
By:Rob Macks
Date: 11/29/2001, 12:10 am

: Tried Satin finish Spar varnish on my Guillimot with nothing but trouble.
: Many runs, and sags,even with brushing on as thin as I could, and if I
: touched them with my brush, the surface left brush marks that needed to be
: sanded out. I have used the Spar #1015 high gloss without a problem many
: times. I like the look of Satin finish, and would like to find out the
: trick!!! Thanks Don

Here's the trick:

My brushed finish looks as good as a sprayed one. I use Captain's varnish.

For those who have not seen my finishing method I'll repost it. I read a recent post talking about the spots missed varnishing. The criss/cross varnish application I describe has made a BIG different in the reduction in spots missed and dips and sags.

Rob's finishing technique

The longer you can wait for the epoxy you are coating to cure the better. I like to wait at least two days for the epoxy to cure on my boats before coating with varnish. The first coat will take longer to harden than subsequent coats.

Oil based varnishes require a surface sanded with 220 grit paper. This is the finest grit you need to have prefect results.

Check the information supplied with the finish for application.

Dealing with Dust
Your shop is a dusty place. Every time you move around the shop the dust gets kicked up. This will land on your fresh coat of finish, unless you take steps to reduce the dust in the air. First, vacuum up as much dust in the shop as possible. Let things settle at least overnight. DO NOT run the tablesaw the day you will varnish. Table saw is are the worst dust offender.

An hour before you will apply finish, sprinkle water on the floor to keep the dust down and mist the air with a plant water mist sprayer to pull the dust out of the air like a fresh rain.

Vacuum all boat surfaces to remove dust or wipe down wet sanded surfaces with clean water and wipe dry with paper towels.

Go over the dry surface with a tack cloth.
For the finish to cure properly your shop temperature should be at least 70° F. Maintain this temperature until the finish is dry.

Use every spotlight, desk light anything you have to illuminate the boat with STRONG light so you can SEE what you are doing. I can't emphasize this enough.

After many years of trying water base finishes and many different varnishes, I now finish all my boats with Z Spar Captain’s varnish. This is the compatible varnish for use with System Three resins. Check with your epoxy manufacturer.

Varnish
As I said before after trying a great many finishes I’ve settled on using Z-Spar’s Captains varnish. I use straight from the can unaltered. Some varnishes say “not to used below the waterline”. This applies only to boats that are moored in water. Varnishes often say “thin 10% with mineral spirits on first coat.” This applies only to bare wood applications. Captains brushes like a dream and creates a great finish.

I have tried every method of dealing with paint can sealing and pouring and keeping the air from drying out the varnish. I’ve never had consistent luck with sealing paint can lids, keeping the lip clean and turning them upside down without leaking. If your varnish is not fresh, clean and scum free everything else is a waste of time.

I now recant my new varnish in quart mason jars with separate lids and screw rings. The mason jar allows me to pour varnish without the lid mess of a paint can. I wipe the jar lip with a paper towel after pouring so the lid won’t stick. By using the separate lids and screw rings of the mason jar I don’t have to worry about not being able to get a lid off if I missed some varnish on the jar lip. I can always pry the lid off and use a new one if needed. I pour varnish into the bottom of a half gallon plastic milk carton. This size carton accommodates my 4” foam brush. Any used varnish gets poured back into the jar unless it is contaminated somehow. Before closing my jar lid I blow propane gas from my small shop torch into the jar to displace air to keep the varnish from skimming over.

Brushing on a Finish
Brushing on a perfect finish is an art that can take time and patience to master but here are some helpful pointers.

Go over the surfaces with a tack cloth (available at most paint stores). All the sanding of your boat will give it a static charge which will attract dust. Going over the surface with a tack cloth is essential to remove dust before varnishing.

Most novices apply too thick a coat and find the finish has runs or drips.

It is best to start with too little rather than too much finish on a surface. This will allow you to get the “feel” for that particular finishes brushing characteristics. Each finish brushes on slightly differently.

Use a good 4” foam brush to apply varnish. I used to advocate costly finishing brushes but they take a lot of work to clean and I’ve found a foam brush can work as well. I hardly ever use a 2” brush unless I’m working on only tiny parts. The 4” will coat twice as fast as a 2” brush AND can do small stuff too.

Be careful around cockpit coamings and hatch openings because the foam brush carries a reserve of varnish that will pool out when pressed and leave a sag of varnish.

Brush Technique
Dip only the tip of your brush in the finish and do not wipe off finish on the edge of the can. This can add foam to your brush.

The toughest part of applying a finish is to put on the right amount, so you don’t get drips or sags and yet cover the area completely.
It seems easy to cover the boat with finish but, I never seem to go without missing a few spots.

At a boat show a finishing rep displayed this brush technique; brush a small area (about 16” sq.) with the grain, then across the grain and finally with the grain, to spread the finish evenly and cover the area totally.

Do all 3 passes one right after the other. When your brush comes out of the varnish container it's loaded. The first stroke (start at the keel or high on the boat) dumps a lot of varnish and successive stokes, with the strips, lay out less and less. Then stroke across the strips, from top to bottom, pulling the first stroke that was heavy with varnish down to even out the varnish layer. Then the final strokes, again with the strips, smoothes it all out and insures you've not
missed a spot. You should be able to do all this with one dip from your varnish.

I now use this brushing technique and have much fewer drips and sags.

To prevent missing areas divide your brushing area into small sections. I use staples on my hulls below the waterline so I brush from the staple holes from one station to the next. Overlap your brush strokes form one section to the next.
If you don’t have a definite area marker like staple holes you will have to mentally guess an area work size.

I estimate a 1/2” dip of my brush into the finish will cover about a 16”. square area.

Look for the reflections of your shop lights highlighted in the finish to make sure you have covered the surface completely and overlapped areas previously brushed. Look for drips or sags and brush them out before the finish sets.
If someone looked in my shop window when I was applying a finish to my boats they would get quite a laugh at the contortions I go through. I look high and low to see my shop lights reflected in the finish to make sure I haven’t missed a spot.

You must wait until the next day before recoating an oil based finish. I usually apply varnish in the evening.

Sand between coats with 220 wet/dry sandpaper. I like wet sanding since it creates no dust and is very efficient. Do a thorough BUT LIGHT sanding job and level any drips or sags. You want to knock down dust and high spots and provide a little tooth for the next coat to bond to NOT sand the previous coat off!

Wipe down surfaces with a sponge and clean water until you have removed all sanding residue. Wipe down surfaces with the tack cloth before recoating.

I apply at least three coats of varnish. This should work with any brand of varnish but as
I said earlier, each brand has slightly different brushing characteristics. This is why I use
Captain's varnish. I just like the way it brushes better than any other I've found. I've tried the Flagship but it doesn't brush as well in my book.

All the best,

Rob Macks
Laughing Loon CC&K
www.LaughingLoon.com

Messages In This Thread

Material: Satin Finish Varnish trouble
Don -- 11/28/2001, 7:53 pm
Re: Material: Satin Finish Varnish trouble
Nick Schade - Guillemot Kayaks -- 11/29/2001, 9:25 am
Re: Material: Satin Finish Varnish trouble
Rob Macks -- 11/29/2001, 12:10 am