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Re: Varnish Questions
By:Rob Macks
Date: 6/20/2001, 12:23 pm
In Response To: Varnish Questions (Steve)

: I've started using the Captains Z spar and after 3 coats I have noted that
: some people are using the Flagship as it has better UV protection. Can you
: change to this kind readily or do I have to sand off the original varnish
: first? Also, on the last coat of varnish how do you remove any sags from
: the final finish without dulling the gloss. It seems that I just can't
: help but get a couple sags each coat.
: TIA
: Steve

I've tried the Flagship but it doesn't brush as well in my book. Each brand of varnish or any finnish, 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.

For help with other finnishing problems I'll repost my technique.

Rob's finishing technique
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.

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

Vacuum all 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.

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 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.

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. See illustrations at left.

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've said I use Captain's varnish. I just like the way it brushes better than any other I've found. I have very consistantly excellent results.

All the best,

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

Messages In This Thread

Varnish Questions
Steve -- 6/20/2001, 10:58 am
Re: Varnish Questions
Byron -- 6/21/2001, 10:24 am
Re: Varnish Questions
Alex Warren -- 6/20/2001, 6:05 pm
Re: Varnish Questions
Rob Macks -- 6/20/2001, 12:23 pm
Re: Varnish Questions
LeeG -- 6/23/2001, 10:34 pm