How Many Coats of Varnish?

[Don Maurer]

How many coats of varnish does it take to get a mirror finish on new mahogany? I have just applied the fifth coat to my dinghy's trim and it is still sucking the stuff up like a dry sponge. I applied 1 coat of CPES, and now have 5 coats of Captains varnish, thinned about 10% over it. I have been buffing each coat with a scotchbrite to give it some tooth before the next coat. Now,I have a fairly even matte finish (before buffing) with a few areas of gloss. It looks like the grain is pretty well filled. So how many more coats will it take to get a mirror finish?

[On Vacation]

In past experiences with good mahogany and captains and good sanding down, 10 coats .

[videoguy]

ten coats sounds good . But I never thin the varnish after the first two coats. ........Phil

[Paul Scheuer]

Maybe something other than Scotchbrite until you're sure that it's flat. You could be roughing the hills and the valleys. It can go on forever.

Once I know I'm sealed, I go very lightly with a hard backing block and fairly agressive paper (200 or so) to get to that mirror flat surface. Then the Skotchbriting starts. Don't forget the tack rag.

I did a piano once. I say that I applied 10 coats, but I must have sanded off 6. Only buffed the last coat.

[Roger Cumming]

Having tried Captains varnish as well as several others, I have found Interlux Schooner varnish to give the best results on our sailboat. It's slightly more demanding to apply, and takes practice, but the results are superior, and it lasts extremely well.

[pcford]

It's not the number of coats. You keep going until you fill the wood. This depends on the varnisher, the brush, the varnish and who knows what else.

Scotchbrite should be used only for the first couple coats, then 320, 400 for the final coats. Final coat sanded with 1200, 1500 and 2000 then buff.

Epoxy coating for first coats was a fad around here about 15 years ago. Don't like the idea. What are you going to do when you have to recoat?

[lumberdude]

http://www.imagestation.com/picture/sraid46/p704f558c2147f612f4e2180fc649cff5/fccb0fe6.jpg

This is somewhere between 12 to 15, I lost count....

Kory

[Concordia..41]

Kory's right. Counting just adds to the obsession. Keep applying until you're satisfied. I generally go for an odd or even number over 10.

Sarah's transom has an odd or even number greater than 30 (and I'm not satisfied).

Seriously Don, you've got good advice so far. Especially about thinning. I've heard it said that the old masters used to let their varnish stand and thicken before applying. I just consider myself lucky if every flying insect in a 3 mile radius doesn't come calling.

I'm undecided on the scotch brite personally. On the first few coats I really like it in situations when dust is a factor, but then again the object is to sand off the tops of the "mountains" and thus you must produce a fair amount of dust to do any good.

I try to get at least 8 good thick coats on before I start leveling the mountains. Think about the volume of varnish you've used. If you're half way through a new quart can on a relatively small area, you've got more varnish on then you're giving yourself credit for. Unless of course you've sanded it all off between coats. :(

A couple of things about your post bother me. After CPES and the first coat or two, your varnish should be building up, not soaking in. It's actually physically impossible. Also, having a matte finish in some areas and a gloss in others is something I haven't achieved and I've pretty much done everything wrong (more than once). :rolleyes:

G'luck.

[ken mcclure]

Originally posted by Concordia..41:
...I generally go for an odd or even number over 10. ...:D :eek: :rolleyes: :D

[Kelsey]

I agree with the 10 coats..that's a good starting point. One related question though, if a sealer, such as CPES is applied first, do you really need to thin any of the coats of varnish?

[pcford]

How can you count coats not knowing how what kind of varnish, what kind of wood, what kind of brush and all the other factors? (A foam brush puts on not much more than 1/2 of what a bristle brush.)

I never count coats. That's superflous. You just go until it looks right. Could be anything from 8 to 14. Maybe more, maybe less.

[Don Maurer]

The reason I'm thinning the varnish is because I have a lot of vertical surfaces and I don't want runs. I tried the second coat with about 5% thinning and got some runs on the transom. I may try the sixth coat staight, making sure to spread it thin. I'm using foam brushes. I'm assuming the reason some areas are a matte and others are glossy is a difference in the wood density or CPES absorption. I am planning to lightly sand the 5th coat with 320 wet or dry sandpaper to even things out, then probably go with 400 grit to the last sanding,which will be 600 grit.

[Bill Berrisford]

Don-
One of the hallmarks of our production boats is the glass finish on the brightwork. We start with a filler-type stain, then two coats of sealer, then 6 or 8 coats of Epifanes (sprayed hot, two coats at a time with setup time between coats). Filling the grain with the stain probably saves 2 or 4 additional coats of varnish. You can't limit the number of coats...whatever it takes.

[capt jake]

Don, I am not an expert on this, but I feel your pain. I switched from the foam brushes to an inexpensive brush from the local big box store (not chip brushes). I have had much better luck with those brushes, though this particular one, I can't seem to find the right cleaner to clean them out. Heck, at 2.50 per brush, they go quite a ways before they are bad. Anyway, the foam didn't work for me (unless it was thinned about 10 percent). I like the bristle type of brush better now.

I feel the pain and after reading this, it makes me think that I may need to scuff and apply again!! smile.gif smile.gif Though what I have looks good to me....... ;)

[Paul Scheuer]

Capt: I too am a proponent of cheap "basting" brushes. When I'm in varnish mode, I wrap them in a sandwich bag and put them in the freezer between coats. They'll usually go for the building coats on a one or two a day basis. It doesn't hurt to freeze the tack rag as well.

[John Blazy]

Great tip Paul on extending the life brushes by putting them in a freezer, as long as you are using the same coating. After many years of experience in high-build, "glass - look" finishing, I agree with Bill about filling and sealing. Much of all your costly topcoat is being drunken up by the open pores of the wood, even if sealed with a CPES. The logic behind using fillers and sealers is to save money applying the bulk of the coating in filling stage (sealers are very simple formulas with higher solids content), while then topcoating with the hi-performance coat (costly due to all the additives, and costly urethanes). Fill the pores with a good filler. I used to use Famowood thinned a little, even with red autobody putty till I realized that you get solvent swell, so I went to 100% solids Polyester, so on my new boat I plan to do its boatfinish equivalent - epoxy based filler. Thanks also Bill, for the topcoat tip, care to share what kind of filler you used?
I plan to go a little unorthodox and take sanding dust, staining it with my red waterbased stain, and mixing with epoxy, then squeegeeing it on, scraping off above the pores (Mahogony).

Also, I don't sand between coats with such fine paper or scotch-brite, as this may be too smooth to allow good adhesion. I sand the First few seal coats with 180 then used 220 before last. - JB

[On Vacation]

Can't wait to get slammed on this one. Colored fillers are a nightmare down the road for touch up. It will also difuse natural grain depths through the finish coats in the better woods. DUCK!!!

[pcford]

Can't wait to get slammed on this one. Colored fillers are a nightmare down the road for touch up. It will also difuse natural grain depths through the finish coats in the better woods. DUCK!!!

As you suspect, you will get disagreement on that. Filler stain accentuates the grain. Some woods, for example mahogany, look flat without it. It should not obscure the grain if done correctly. You will have to refinish the whole contiguous panel. There is no effective way to patch stain.

[On Vacation]

I will go a step further on this one. In many times when you use a filler stain, the initial coat of varnish will lift and discolor areas if the stain is not properly done. This is an issue that most people of less experience will find when attempting to stain their wood. We are using a water based stain to eliminate this happening in furniture refinishing now.

[B. Darrah Thomas]

Originally posted by lumberdude:
This is somewhere between 12 to 15, I lost count....
SWMBO does the varnish around here, (Don't throw rocks at me it's just our way), & anytime she loses count, the quality is just right.

[John Blazy]

Water-based stain is pretty awesome. I made my own "blend" on my new boat to make the skins of the superply look like mahogony by mixing Rosewood WB stain and an alchohol based Walnut dye stain from Mohawk, and it didn't raise the grain much at all, and with no VOC's or danger of spontanious combusting rags (had this happen). Adhesion of sealer is great too. - JB