NAPTHA AS VARNISH THINNER

[stephen e morris]

As I go about restoring this old Peterborough canoe an experienced hand tells me that NAPTHA is the best thinner for an initial penetrating coat of varnish.This is news to me and I wonder if there are any folks who know about this use for naptha.For that matter,can it even be had anymore !?

[capt jake]

I haven't used Naptha for thinning varnish, but I recently used it for thinning an oil based enamel for spray application. It worked out great!

Naptha is readily available at all home improvemnet and paint stores.

[stephen e morris]

sort of answered my own question.Jamestown stocks it as a fast thinner...thanks anyway folks.

[pcford]

Best to follow the instructions on the can. Took me many years to figure out that one.

[Concordia..41]

Oh thechemist Why Hast Thou Forsaken Us :(

Ok nevermind. Seriously Stephen from your member number, you look new to the Forum so WELCOME.

Once upon a time the Forum once had a member who went by thechemist who would respond with a mini-thesis to a question like yours. If it's not in the FAQ post, follow the Google search instructions in aromatic and aliphatic solvents.

thechemist wrote several informative pieces, which are hopefully still accessible through the archives.

Basically solvents come in two flavors: aromatic and aliphatic and each work in different ways. Also somewhere in the archives is thechemist's list of what solvent works with what paint/varnish/etc.

[ssor]

Forgive my faulty memory but I seem to recall a label V&PM on the can of napha, which meant Varnish and Paint material. Help anyone? redface.gif
Personnally I have never wanted a fast drying varnish I want to keep a wet edge for as long as I can.

[ 09-06-2005, 08:38 PM: Message edited by: ssor ]

[Concordia..41]

ssor - it is all relative. Down here, I often use an accelerant to offset the humidity level and thus have less time for every bit of dust, dirt or pollen in the air to land.

[ssor]

It is also a great way to catch gnats, midges, amd other flying things. They seem to be attracted to glossy white paint. :(

[JimConlin]

I'll use it if i must varnish in damp, cool weather. It flashes off a bit faster than turps.

[pipefitter]

And it makes for an industrial sized supply of zippo lighter fuel smile.gif

[SandMaster]

Too quick a cure makes for a more britttle varnish.

[JimConlin]

As I understand it, two different things happen after varnish (or paint) are applied . First, a good fraction of the solvent evaporates, then the resins in the varnish or paint react with the air and harden. Accelerating the first stage by using a lighter solvent doesn't affect the curing stage, it just hastens the point where the varnish is gooey enough not to level or sag further.

[Scott Rosen]

I keep a supply of naptha for thinning paint and varnish. As best I can tell, Interlux brushing thinner 333 is just very expensive naptha.

Where possible, I use the proprietary thinners. But Kirby's and McCloskey's don't have their own thinners. Naptha and turps are my thinners of choice for those.

If you want to be methodical about choosing a thinner, then go to the MSDS for your brand of varnish, and see which solvents are used by the manufacturer. Use the same solvent for a thinner. Naptha is used in a lot of different paints.

[ 09-07-2005, 09:28 AM: Message edited by: Scott Rosen ]

[pipefitter]

I have also noticed the vm&p naptha at the home centers doesn't smell like regular naptha. It has a hint of kerosene smell to it.Straight naptha smells identical to zippo lighter fuel. Also,I have been using mineral spirits to clean my brushes with at about 6-7.00/gal and this time I got a gallon of stuff called "paint thinner" for 5.00 and it includes mineral spirits as an ingredient with "conditioner" added. Again this smells like kerosene as does the 333 brushing liquid.The old man I painted houses with for years used to store his natural brushes in kerosene with some linseed oil added I think.Straight mineral spirits seems to gel the brightsides after a few days. I noticed this when I emptied the brush cleaning container.

[ 09-07-2005, 10:38 AM: Message edited by: pipefitter ]