There have been some fine postings on how to varnish. I think I have a copy which I will attach for your interest. Me personally I played around with little mini sponge brushes, cloth, kitchen sponges and finally just a plain old paint brush. I think I get the best coverage and best finish with the plain old paint brush and that is my call.

Having used a random orbital sander for the first time recently I can't rave on about how good they are. I was happy with my sand down to 220 grit disk that I never bothered with the wet and dry hand sanding. But then I am a rough tough sort of guy and varnishing over that was better than I ever imagined I could ever get. Happy with that!

I am thinking about touching up my Guillemot S&G after a summer of reasonable use. The boat is stored in my garage and doesn't need re-varnishing - it is just a guilt thing for me: I only put 5 coats on the deck and 3 on the hull before Christmas. "Enough with the varnishing already, its time to do some serious paddling!". You know how it is.

Good Luck with your project: Pete

Re: Wet sanding and varnishing.
Posted By: Rob Macks
Date: Saturday, 28 July 2001, at 2:23 p.m.
In Response To: Error! Bookmark not defined. (John Monfoe)
: The advise from the board to use a lot more water while wet sanding was great
: information and made the job fast and fun. I tried the technque of wiping
: on a second coat of poly varnish 2 hours after the first coat and it
: worked fine also. So yesterday, I sanded, varnished the deck, waited 2
: hours and varnished it again, waited 6 hours and turned the boat over and
: repeated this on the hull. A good day. I tried the 600 grit to see how it
: would look for a final finish and did the same thing with #0000 steel
: wool, in selected spots. The wool give a better satin finish and very easy
: and quick to do, but I think I like the shiny finish better. So after
: sanding this morning, I will try my hand at a final brush finish as Rob
: Mack does and if I do a decent job that will be my final finish for now
: and maybe polish in late fall. This will be coat #7. Thanks for guiding me
: through this.
: John
Unless you are buffing out a finish any grit over 220 is a waste of effort when varnishing an epoxy coated boat surface.
And unless your boat will never leave the walls of a museum, show room, or if the selling price is over a mill, it’s a BIG waste of effort to buff out a boat finish. Buffing out a finish is not something you learn on the first try.
All the marine spar varnishes I’m familiar with (and I’ve used quite a few) suggest sanding ONLY up to 220 grit before application.
I’ve been sanding for over thirty years. I used to HATE sanding. I still don’t love it, but it’s bearable when you know what you’re doing and what grit to use.
320 is used with the water based finishes because these are so thin, and 400 and 600 grit papers take down a very small amount of material.
Hand sanding is MUCH less effective than power sanding.
I be willing to bet dollars to doughnuts if you sanded with 400 or 600 grit a careful examination of the surface would reveal a LOT of remaining 220 grit scratches. I've made jewelry where you have to polish a metal surface to mirror perfection, and believe me, removing the scratches from a previous grit paper are a lot harder than you think even on a softer surface like epoxy by hand sanding.
The idea of sandpaper use is to level the surface with a course paper like 80 grit then, depending on your surface hardness, use lower grits to remove the scratches of the previous grit to a level appropriate to your finish. For the soft woods we use on kayaks a 80 -100- 150 grit progression works fast and well, to prepare for epoxy.
When all my glassing work is done and I'm ready to finish the boat I rough sand with 80 grit. Then apply two final coats of resin. This covers all feathered glass edges and any cloth weave tops I might run into. This coating will be very smooth almost looking like it’s varnished. Then I can start sanding this smooth surface with 150 grit and then 220 with ROS and finally going over it with 220 wet hand sanding before varnishing.
By adding two final coats of epoxy before finish sanding I know I will not be cutting into my glass layers.
NOW IF you were applying a hand rubbed oil finish penetrating a bare wood surface you would want to sand to 320 or even 400 grit since the oil will be sucked into the wood and the build up of finish on the surface will reveal very small scratches
BUT on a non-absorbent surface like epoxy 220 grit scratches will be totally filled by one BRUSHED coat of marine spar varnish.
All the varnishing literature I know of deals with coating bare wood surfaces NOT epoxy coated surfaces, so with this in mind, thinning the first coat of varnish is not applicable to epoxy.
With boat surfaces sanded to 220 grit (wet/by hand or dry/using power ROS) it’s possible to achieve an extremely easy, consistent, beautiful finish following the varnishing technique I’ve outlined here before.
I invite you to look at the boat finishes on my boats at this fall’s Newfound Rendezvous.
Of course there are different ways to apply a finish. For the novice finisher (anyone who’s finished under 20 boats) I suggest following the directions of SOMEONE who has applied a marine finished professionally. If you don’t like my method there are many fine books on the subject. Remember almost all will be on finishing wood rather than epoxy surfaces.
Just like the many variables involved with epoxy application there are many variables to control to achieve a fine boat finish. It does take time and experience to do a good job consistently. When you work alone you have no one else’ work or work methods to compare what you’re doing to it is easy to waste a lot of effort especially if you pick and choose among different methods.
When we get to the point of completing the boat we’re eager to get it wet. So subtitles of applying a finish can be overlooked. BUT the beauty of strip building is you can put on a new finish next week or this winter and your boat will look that much better for it.
I dearly wish I might direct someone away from wasting their time and energy on procedures that will do nothing to improve their boat.
I encourage you rather to take all the time and effort needed to align and fit your strips as exactly as you are able to. THIS more than any other aspect of building will save you time and effort in EVERY OTHER PART of the building process.
I believe your strips MUST be tacked STRONGLY to the stations somehow. If you are using a stapless method that doesn’t connect each strip firmly to the station you are making the possibility of stripping tightly and following the forms accurately extremely difficult.
Most of my designs have concave sections to the hull that must have strong contact with each strip to be constructed accurately.
I hope this will be helpful to at least a few out there.
All the best,
Rob Macks
Laughing Loon CC&K