Thread: Ventilation for priming.

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Way back in the past, I used an exhaust fan to blow paint fumes out of my garage when priming. However, I have long been nervous about that because of the possibilitiy of a spark from the fan igniting the fumes.

The last car I painted at home, I used two fans blowing into the room through filters to keep the dust out, and left a crack under the garage door for an exit. It worked really well.

I'm about to prime my Gibbon '34, and decided to use the positive pressure method again. I cut a piece of plywood to fit against the jambs in my garage side door, then mounted two box fans (pushing) on one side and filters on the other side. My only problem now is that the filters may be too good. They really cut down the airflow. When I do the final basecoat/clearcoat, I'm going to try to find a paint booth to rent.

Any thoughts on the setup?

You might look for filters that are less restrictive, like cheap furnace filters. They won't stop everything, but they'll catch the big chunks!

The system basically worked. Using my HVLP primer gun, I had virtually no fog in the garage. There are some tiny specs of dust, but it's primer, so I'll sand it out. I have to block it again anyhow. The primer (catalyzed polyester) is taking a bit longer to dry than normal . . . I probably should have waited until it was above 60 degrees. I keep forgetting how different a project looks when you get all of the mottled colors from blocking covered up with a single color. The best part is that I did not blow myself up. My next step is to fill all of Gibbon's pinholes.

Based on how this went, I may just do the basecoat/clearcoat in the garage - albeit with quite a bit more cleanup and draping the shelves with Visqueen.

Looks great. Funny how getting a little primer or paint on makes it seem like you have taken a giant leap forward in the project.

Gonna be a nice rod.


Don

yeh know i always wondered about using just plain fans like that and i have a few of them in the house .the one i have are brushless no sparks cannot see how they could blow anything up except heat up and start on fire

Good progress Jack. If you've done the job in the past without an HVLP you probably remember sweeping up a lot more primer particles from the floor.

One comment on doing the top coat in your home system, especially if you pound on the clear to give plenty to cut and rub. I'd be leary of solvent pop with that little air movement and possible lower heat. Booth rental may be more costly and time consuming, but you'll probably enjoy the fininshed product more.

Al,

Mine are pushing, not pulling, so no fumes go through the fans. The exhaust goes out under the garage door.

Bob,

It will be a while before I do top coat. This is the first primer coat, and I have some blocking to do. Oh, and I won't have to worry about heat here in southern Virginia. By the time I get to the top coats, I'll be looking for the slowest activator they have. Thanks for the heads up about air movement, though. I'll have to work on that. I may put a couple of pulling fans at the garage door. Since the fans have shaded pole induction motors, there are no brushes, and no sparks.

Jack
- My floor is still sticky . . .

Henry Rifle---It looks great. It is always quite a thrill when that first coat of primer or paint goes on and everything is all the same colour.---Brian

Looks good Jack....How many hours of blocking and fixing so far???

When I paint in the garage, I use an old squirrel cage fan with a 18" duct on the end of it... I have the motor mounted below it and run a long belt. The fumes and overspray goes out the duct and not anywhere near the electric motor. Kind of primitive, but it sure does move a lot of air. Just picked up another squirrel cage fan, so going to order another cheapo-cheapo Dayton motor and run two of them. My air intake is the window, with 2 furnace filters in a wooden frame... I still prefer using a paint booth, but it's not always available when I need it....

i know an old bodyshop guy that runs a exhaust fan kind of the same way. he has a big auto fan mounted in a steel barrel with a belt and a 1 hp motor on top. is moves a ton of air.

yup, an attic ventilator would work too, just so the motor is detatched and out of the airflow....

Bob,

I used to keep track of all my hours on my projects, but I gave that up years ago. However, my best guess is that I have better than 200 hours just fixing Gibbon's mistakes, like the driveshaft tunnel, the garnish moldings, the floor pan to body joint and several broken/missing corners on the hood, doors and trunk

I estimate about 100-150 hours so far in blocking the gelcoat and bondo fill to get rid of the major low spots, body joints and gaps. At least Gibbon used a nice, thick, sandable gelcoat. Small favors. This is the first coat of sandable primer, and I'll probably block and sand three or four primer coats. It should move faster now. Then, I've got a white sealer that should make the final yellow pop.

I'm glad I'm not paying someone . . .

about what I figured. Last Gibbon body I did was a bit over 250 hour from crate to paint..... ridiculous...

Originally Posted by Henry Rifle

Bob,

II'm glad I'm not paying someone . . .

Well Jack, at least you know what you're worth!

Apparently Gibbon was having a sale on pinholes when I bought my body. So much for the "chopper gun is best" theory.