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Re: Varnish Advice Needed!!
By:Rob Macks
Date: 5/7/2001, 5:01 pm
In Response To: Varnish Advice Needed!! (Byron)

: I've having a tough time getting that final "mirror" finish on my
: deck. I'm using "Flagship" varnish and I've had one of two
: issues. On the first coat, per instructions, I thinned it just a bit with
: T-10 thinner (recommended by the Flagship maker) and applied with a good
: brush (badger bristle?). I got quite a lot of what appears to be
: ultra-fine dust. (This is even with cleaning deck surface thoroughly,
: using a well cleaned, quality brush, using new, non-contaminated container
: for the varnish, using an air cleaner for an hour before varnishing, ad
: nauseaum...)

: For coats # 2 & 3, I used unthinned varnish and the brush, etc. Results
: were a bit better, but I must have applied the varnish a bit heavy/thick
: because while the grit was largely gone, there were noticeable ridges (at
: least to me) in the finish. I presume this was due to the fact that the
: varnish is a bit thick and needs a bit of thinning to flow properly.

: I'll sand it down...ONE MORE TIME :-) ...but would REALLY like to make the
: next coat the last coat for this year!

: Has anyone else had issues trying to thin Flagship varnish with T-10? Perhaps
: T-10 is contaminated somehow and needs to be strained before using it?
: (I've only used a tablespoon or so at a time anyway...) I'm afraid to stir
: the thinner in too vigorously for fear of creating bubbles which will of
: course show in the finish as well. Is there an alternate thinner to try?
: Maybe running the air cleaner a bit longer prior to varnishing? What am I
: missing here?

Thinning the varnish is only needed for coating bare wood.

After you've sanded and resanded the epoxy on your boat you've created a great big dust magnet. I varnished two boats recently. For some reason the static charge was worse than usual. As I wiped down the surface with a wet sponge to remove sanding dust the hair on my arm bristled.

I went over the surfaces a number of times with my tack cloth and continued to have a hard time removing all the dust specks.

Yes they are tiny bubbles but they're still caused by dust.

Now that my first coat is on the hulls of my boats the static charge is gone. After I sand this coat with wet 220 and recoat, the specks will be greatly reduced or totally gone.

This is why you need to sand between coats if you want to have a good finish. It's hard if you've never had good results to be patient and take the time to sand carefully and go through all the steps needed to have good results. You're almost finished and you want to get the boat in the water. But all the work you've done so far will look dull under a poor finish.

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
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 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

Varnish Advice Needed!!
Byron -- 5/7/2001, 10:56 am
GREAT Suggestions/Thank You
Byron -- 5/10/2001, 5:37 pm
Dust free now for 5 years
edgar -- 5/8/2001, 8:00 am
Re: what is this?
Dan Lindberg -- 5/8/2001, 1:49 pm
Re: what is this?
edgar -- 5/9/2001, 8:02 am
Re: Thanks Guys
Dan Lindberg -- 5/10/2001, 1:11 pm
two links
tony b -- 5/8/2001, 4:40 pm
Re: Dust free now for 5 years
Ross Leidy -- 5/8/2001, 8:34 am
Re: Varnish Advice Needed!!
Angela Watson -- 5/7/2001, 8:13 pm
Re: Varnish Advice Needed!!
Pete Croft -- 5/8/2001, 12:00 am
Re: Varnish Advice Needed!!
Alex Warren -- 5/7/2001, 8:00 pm
Re: Varnish Advice Needed!!
Rob Macks -- 5/7/2001, 5:01 pm
Tack cloth - Type/Manufacturer?
Andreas Albat -- 5/8/2001, 11:34 am
Re: Tack cloth - Type/Manufacturer?
Rob Macks -- 5/8/2001, 1:51 pm
Re: Static
Nick Schade - Guillemot Kayaks -- 5/8/2001, 9:04 am
Discharge that charge---
Jerry Siegel -- 5/8/2001, 11:28 am
Re: The Perfect Finish - Polish
Dave Houser -- 5/7/2001, 10:58 pm
Re: Varnish Advice Needed!!
Dan Ernst -- 5/7/2001, 1:14 pm