Steel Advice - The Fabricator's Resource
Dedicated to support the steel fabricator with real world solutions to real world problems.
The Painter's Bucket
Always know what your flash point is. Flash points do vary between paint types, so check the product specifications for this information.
The flash point is the temperature at which a VOC containing material releases volatile gasses enough so that when mixed with air, it has the potential to ignite IF there is an ignition source available.
As your water heating unit is under water and the power source is in another room, the only two sources of ignition are contained as long as they stay where they belong. Be sure that they do.
Be careful that your paint does not get hot to the point where it is too runny, as this will create the same problem that adding too much solvent does.
One of the commonly bantered about thoughts in spray painting application is the notion of using heat instead of solvents to aid in proper paint application. The practice is that by heating the spray material, viscosity is lowered, and the coatings material atomizes correctly instead of having to use solvents to lower viscosity. Using heat to "thin" paints has several advantages:
- Negates the use of harsh solvents from the shop.
- Lowers applied VOC content (important for state jobs and in regulation-heavy areas)
- allows you to 'dial-in' the exact viscosity desired (solvents work in one way only by avoiding over thinning
- the application of heated coating material significantly reduces cure times.
So why doesn't everyone do this? Well, the answers are somewhat obvious. First, most paint applicators are so used to thinning paint, that introducing a new concept to them is sometimes difficult (teaching an old dog a new trick). Second, using heat takes a little time, and the steps have to be pre-planned. Using heat as a thinner is not something you can decide to do five minutes before the project begins. Lastly, safe heating equipment is usually expensive.
We can't fix the first two shortcomings, but there is a solution to the last. Typical paint heating equipment consists of a circulating pump with an inline heater. Paint is pumped through a circulation hose, into a heating element, then back into the mixing bucket in a continuous loop during the entire spray operation.
The backwoodsman solution to this is to make a 'double boiler'. By taking a farm stock tank water heater and placing that in a bucket of water larger than the bucket of paint (run the cord outside the paint area, my friends) to heat the water with and then placing your bucket of paint in the warming water, you can take a can of paint that is thick like jell to the consistency that is required to apply the paint correctly, possibly without thinner at all. With the heating element submerged, and the power cord outside the booth, there is no code issue violation or safety hazard to worry about. You may want to use a brick or two to elevate your paint bucket a bit as the key here is to have enough water around your paint to provide enough heat transfer. As an added bonus, this process will also shorten the cure time of the paint. Great news for colder weather applications!
Keep the lid on Solvents! Use (low) heat to 'thin' paints
Before you go using this idea on your first project, try it out with a small job as a test.
Keep track of the temperature and how long it takes to get the paint to that desired temperature.
Keep track of how long it takes to cure and make a note of the DFT reading on that first coat of paint.
Recording this information will help you to gauge your next and future projects.
Remember - SAFETY FIRST!
Tips on using heated paint