MTFCA Forum

I am getting ready to paint my newly rebuilt wheels for my 1912 Roadster. They will be painted the very dark “Midnight Blue” using PPG Single Stage urethane enamel. I searched the forum extensively to see what preparation the wheels require and found all kinds of advice. So much so that I have gotten myself confused. Some say to seal the wood with Kwik Poly, some say oil-based primer, etc. One reputable fellow on this forum recommends spraying with Slick Seal, sanding the wheels, then proceeding with paint. I thought I would ask the question again and maybe get the “latest” thinking on prepping rebuilt wheels for painting.

My question boils down to: do I need to “seal” the newly rebuilt hickory wood in my wheels prior to painting with primer and urethane enamel, and if so, what do you recommend? I certainly only want to do this job once!

Yes. Even with thorough primer sealer paint, hickory wheels will soak up finish, where you may multiple touch ups.

My wheel guy recommended coating the spokes with linseed oil.
They painted up real nice.

Go to your paint manufacturer and follow their advice from the ground up. Modern paint chemistries are unforgiving of cross-matching different products. Unless you are going to use an obsolete oil base paint (e.g. alkyd enamel) do not use linseed oil at any point in developing the finish.

It's All About the Base.

If you are using automotive enamel, like a single stage with gloss hardener, be sure to use the compatible sandable primer over sealed wood.

That way you can sand the primer to get a very smooth (i.e.) no wood grain showing, surface that the final finish will adhere correctly.

Have used a quality wood sealer, thin it, and of course lay it on or spray, as it will also form runs that have to be sanded smooth.

The result is worth the work.

Wood spokes sealed with Zinsser brand bare wood primer. Nason gray primer used as final was a light gray for early 1909's. You may want to use a black primer for a very dark finish coat.

Final finish Dove gray Nason acrylic enamel w/ gloss hardener.

I use Penetrol to seal bare wood. It soaks right in. multiple coats can be applied. It is sandable when dry. It can even be added to oil based enamels to extend the paint and help eliminate brush marks. Just check that it is compatible with the paints you want to use.

Allan from down under.

This stuff was recommended to me by a fellow Model T guy. Any thoughts? Seems like it would be workable.

https://www.rockler.com/zinsser-bullseye-sealcoat

I sold PPG products for several years. On all of my wooden wheels I use a 2 part epoxy system called SMITHS PENETRATING EPOXY.
When it dries use a 2 part primer Deltron DPS3055 to fill wood grains. Sand and apply your top color.

My suggestion has to do with filling the grain on a wood body, some pieces of which were oak. I tried various products including a wood primer, wood fillers, a sanding sealer and other products Im too embarrassed to list!. I found the best result came from using Dap premium wood filler watered down as suggested, followed by sanding smooth. Usually one pass was all that was needed. But a few places required a second application. It really works well.
I followed by spraying a watered down wood primer and then a coat of DP90 before delivering it to a pro for finishing.

I'm going to make a bit of a contrarian statement here, so don't say you weren't warned.

Unless you seal the end grain at both ends of the spokes, it really doesn't matter much what finish you use. Here's why:

Moisture is the worst enemy of any wooden structure, not just from organic growth, but primarily because end grain soaks up atmospheric moisture as we go from summer to winter. Any seasonal moisture entering and exiting the wood will cause expansion and contraction. It's usually just a microscopic dimensional change, but it's enough to crack and break down your carefully applied finish. Eventually the finish will give up and most people think it's the fault of the paint.

The best way to provide protection from seasonal moisture change is to put several coats of linseed oil or penetrol on all surfaces of all spokes prior to wheel assembly. Linseed will soak into the spokes and seal them without buildup on the ends. Let the linseed oil or penetrol dry for a week or two after the final coat and then assemble. At that point, the spokes are fully protected.

Once fully dried and lightly scuffed for adhesion the linseed becomes an excellent base for most any paint topcoat.

Just realized that I should have added one more thing:

I don't know that linseed oil is the best thing to seal the ends of the spokes, but it's the only thing I know of that can seal wood and yet not increase the dimensions of the spoke ends. I'd be perfectly happy to use epoxy resin as a sealer, but it would ruin the fit at both ends of the spokes.

So I just use the linseed because it does a good job and doesn't change the fit of the spokes.

Considering the age of many T owners, many of them will not live long enough to see linseed oil dry. Boiled linseed oil, yes; linseed oil, no.

In any event, I am constantly amazed at the effort folks will go to solve problems which largely do not exist.

It would be unwise to cross linseed oil or "old fashioned" oil base paints or varnishes with modern epoxy or catalyzed synthetic coating systems, no matter how intuitively beneficial it "feels" or what your great uncle George, the master woodworker taught you.