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Spray Paint Booth
Part 1: Initial Planning & Purchases
I decided to build a spray booth instead of buying one of the $100 imports.
concept of spraybooth The design is based on a dual squirrel cage fan. The motor will be enclosed in a box that keeps it out of the flow of paint spray. The spray area has to hold an HO 80' passenger car body, which comes out to 16". Exhaust will be at the rear. Base will be plywood and the rest of body of the booth made from 1/8" hardboard (both sides smooth).
BMW fan motor
I bought a BMW replacement blower fan for $30 on ebay. This pic shows the fans removed. A trailer plug has been installed with wire nuts. 5/16" bolts with washers will be used to secure it in the motor box. 		12v 10A power supply
This is a 12V 10A amp power supply. It will sit on top of the spraybooth. From ebay.
12v 10A speed controller
The speed switch. 12-24V 10A. Black wire goes to power, red to power and motor, and blue to motor. Another goodie from ebay. 		trailer plugs used
Two trailer wire cables bought at NAPA. I got different colors so the connections would not get confused.
4x2 terminal block
Electrical block with six terminals but I only needed four. A leftover from a former HO layout. 		1/8 hardboard sheet
1/8 hardboard sheet 48" x 96". I wanted two smaller sheets but each smaller sheet cost as much as the full size sheet. The board is difficult to manage since it is so flimsy.
dryer vent This baffle will be modified and used to vent the filtered air to the outside. Bought at Lowe's.
12 inch light for spray area This 12" light was also purchased at Lowe's. This product has various settings for light intensity, a motion sensor on/off switch, and can be linked to more lights. The unit is very flat.
How do you know it will work?
If the fan can service a car interior it should be able to work for this tiny space.
How do you know the power supply/speed switch/motor combo will work?
I looked at a website where measurements for voltage and amps were given for an interior blower motor from a BMW, but it wasn't the exact motor I purchased. At high speed the motor was using 12V and 10A.
Why is the motor to be located in a box?
The motor has to be isolated from the air/paint spray flow. Fine spray or organic solvents create a fire hazard due to their coming in contact with arcing motor brushes or a hot motor. Keep paint spray out of the motor!
- JH -
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