The Stovebolt Site Forums The Shop Area Paint and Body Shop springs - POR or Powder Coat?

What do you recommend and why?

I've used both on other parts of the truck,(as well as DP primer) but I don't know which is the best idea for the leaf springs.

Thanks for your advice!

http://www.eatonsprings.com/powercoating.htm
What is Powder Coating?

Powder is a dry coating. Instead of being dissolved or suspended in a liquid medium, such as solvent or water, powder is applied in a granular form. This material is finer than ground pepper but coarser than flour, and is applied directly to the surface to be coated.

Powder Formulation.
There are two distinct types of powder, Thermoset and Thermoplastic. The Thermoset powders are reactive, which means that under cure conditions there is a chemical "cross linking", so that, once cured, the coating will not remelt. Epoxies, acrylics and most hybrids are examples of Thermoset powders, making up over 90% of the current powder market.

Thermoplastic powders do not "cross link" when cured, but simply melt and flow over the surface of the part.

The film hardens on cooling, but if it is reheated it will remelt. Vinyls, nylons and fluorocarbons are examples of thermoplastic powders.

Enamel powder is a specialized formulation used in applications that previously used liquid porcelain enamel. It utilizes glass in its formulation and is cured, or fired, at very high heat. The result is a finish that is particularly resistant to heat, scratching and harsh chemicals, and is typically used in appliances, such as washers, dryers, ovens and ranges.

How is the powder applied?
The application process involves applying a charge to the dry powder particles and spraying them onto a grounded substrate. The powder, once attracted to the part, is then held on the surface until it is melted and cured into a smooth coating film in the bake oven.

The powder is fed pneumatically out of the powder container, or hopper, into the powder applicator, or gun.

As the powder exits the gun, a low amperage, high voltage charge is applied to the powder particles, causing them to be attracted to the grounded work piece. This attraction may even cause the powder to "wrap" around the piece, coating the back side.

WOW!!! We now know more about powder coating then we ever thought we would. The above is just a portion of what you will find if you go to www.powder-mart.com, they know everything about powder coating.

Another great source is Eastwood Co. www.eastwoodco.com.

Now to answer the question, is it OK to powder coat springs? Well that depends. In the curing process heat must be used. Too much heat is harmful to springs. Once springs begin to get hotter than 350 degrees Fahrenheit they begin to anneal, that is the steel starts to get soft, the temper is lost and the spring will not
support any weight.

In order to safely powder coat springs the temperature MUST remain below 350 degrees!!!!

If you are debating between powder coating and chroming your springs, powder coating is safer.

1555 Michigan, Detroit, MI 48216
phone 1-313-963-3839 fax 1-313-963-7047
[email protected]

Cheers,
mark.
'51 KY 3100

Do an archive search on painting springs. I think someone makes a high-graphite paint just for leaf springs.

No matter what you do, the coating will not last very long due to the flex of the springs. I would use POR because you can touch it up every week if you want to.

por 15
no question

Ive always used DP90 on chassis and related parts. It looks good and is virtually bulletproof.

Don't over look Zero Rust as well. It is probably more flexible than either the POR or powdercoating, has higher salt spray numbers and comes in aerosols if touch up becomes an issue.
Happy New Year y'all....
Bruce Palmer
[email protected]

As long as Mark mentioned chroming things, I'll do a little side track on this thread. When you chrome items, the process produces a condition in the part known as hydrogen embrittlement.

This isn't fatal, but on a loaded part, it can cause failure. The remedy for hydrogen embrittlement is a temperature soak in a oven for a period of time. I am not sure on the temperature or amount of time required, but know this can be accomplished in a kitchen range. This is how I understand it!

Stuart

I believe Stu that that heat process must take place w/in a specific time period after the plate process, like w/in 60 minutes. So asking a plate shop to do this may be a little difficult.I had a part fail after cadmium plating.

After plating, parts which are susceptible to embrittlement are often subjected to a heat treatment (baking) procedure, called "hydrogen embrittlement relief". Often, a temperature of 375 deg. F for 3 or more hours is used. Sometimes, specifications require that the embrittlement relief bake be performed within a certain number of hours after plating. The process serves to remove or redistribute the hydrogen, but may further reduce the fatigue limit of high strength steels. This phenomenon was described by R.A.F. Hammond and C. Williams ("Metallurgical Reviews", 5, 165, 1960) and again by J.K. Dennis and T.E. Such ("Nickel and Chromium Plating - Second Edition", 1986, p.72).
http://www.corrosion-doctors.org/Forms/embrittlement.htm

http://www.nmfrc.org/crarchive/feb02a.cfm

Jim,

WOW...thanks for the genuine dope on this suject.

Stuart