I make wooden shoe-shaped item of 300mm x 400mm x 100mm. I have to spray these objects, which at the moment mean outside in front of my house. There are a few reasons why it is not a long-term plan? First, winter has just begun and below freezing temperatures does not contribute to spray painting! Second, it's not a good look at the neighborhood to witness me dropping airborne pollutants into the air!
The next logical solution was therefore to spray in my garage / workshop without any health conditions. Therefore, a spray box mounted on my workbench was constructed. A quick google of manufactured booths showed that these are not cheap and far beyond my budget. The alternative of not using a booth means that solvents quickly fill the room with smoke and overspray fog. In theory, can any spark-producing device, such as a switch, light or radio, trigger a solvent explosion? This applies equally to using an exhaust fan incorporated or exhausted from a booth. If your electric motor's exhaust fan is exposed to flammable contaminated air and is not flame retardant, you are at risk! This includes axial type fans used to ventilate bathrooms. My 2hp vacuum cleaner has a motor outside the air flow and does not use the moving air in the fan to cool the engine. The blades on the fan, however, are metal and theoretically if the metal fan blade somehow engages the inner metal fan housing, then can you have an ignition source? Therefore, I recommend that you only suck out if the engine is out of the air flow! Another factor to consider is that you need to exhaust at a speed of 0.5 m / s or 1
Limitation of Liability: This instruction manual does not comply with regulatory standards for a flame-retarded ventilation system! Continue at your own risk because I do not take any responsibility for the consequences?
This sprayer box is larger than the cheap and nasty airbrush booths. The construction needed to be useful not only to spray painting without other purposes:
1 / As an exhaust head behind a compound miter saw, spraying dust in all directions.
2 / As a bench beam at hand grinding with an electric sander
3 / As a photographic studio for still images of finished products! Yes with background plate, the LED lighting on the boat will make a controlled light environment for taking still pictures.
Another requirement was a reasonable final weight (about 20 kg)? Not too heavy to carry and lift on / off the bench. In addition, was it compact and collapsible in any way to minimize storage space?
I was busy using masking tape on the surface of my workbench as a sketch. I have a saw fence that I do not want to remove every time I use this stand, so it had to sit over it somehow? After 3 different prototype designs with Fusion 360 I came up with this design. It is constructed of 12mm MDF. The filter plenum is 600 wide and 900 mm high. With the hinge flanges and the lid on the cover folded out, the opening is 900 mm x 900 mm x 400 mm deep against the front of the filter.
2 of 1800 mm x 600 mm x 12 mm MDF sheets and 1 of 1200 mm x 600 mm.
2 of 900mm long and 1 of 600mm long piano hinges
1off 64mm steel track rail used in housing frame construction
1off 40 x 40mm light guage zinc channel angle used for inner corner reinforcement of gypsum board walls  6 mm dia x 38 mm long hardwood hills
M5 x 38mm Mounting screws
M5 all thread and wing nuts. cut and epoxy 40 mm long all threaded screws in the top plate edge, with wing nuts for quick removal of the cover.
Shellac / Oil based primer and topcoat paint
A 600mm long LED headlight and 2 LED side lights
Spray color filter: Andreae Exhaust Concertina Cardboard 900mm high x 9m long
100mm dia spigot for connection to flexible duct  600mm wide white roller blind
3mm pop rivets
5mm x 40mm bolts and wing nuts to attach light and roller blind.