Styrene, don’t worry, I did not take any of it that way. I appreciate the help. Wasn’t looking for a bunch of “yes” men when I posted.
That’s what’s great about these boards and newsgroups, etc… There is a wealth of information out there. You just have to ask.
Which I did.
Mike - both acrylic and enamel. Plus thinner, lacquer, whatever to thin, clean, etc…
As for the booth - I am not to concerned about venting the booth and room at an extreme level. I figure it it does it pretty good, then that’s acceptable to me. I was planning to get one of those paint/hazardous fumes masks (the ones where you change the filter media from time to time) so I am not really worried about breathing in toxic stuff. And I don’t think an airbrush, for the amount of use per session, will generate that much anyway.
The part I am concerned about is fire/explosion. A few people are saying get explosion proof fans with brushless motors, etc… to avoid it. Because many fans, that have brushes, can sometimes produce sparks which can ignite the toxic fumes produced by enamels, thinners, lacquers, etc… But range hoods don’t even give those specs when you are checking them out to buy one.
I know range hoods are designed taking into account hot air, grease, oil, etc… but not toxic fumes (excluding my ex’s cooking, that is - LOL!) I believe, so don’t know if there are brushless ones or not. Other factors may include whether or not the motor is in the direct path of the (vented) airflow. And then there is the light that comes with a range hood. Is that a potential problem.?
Still lots of questions. LOL!
Anyway, i will keep looking around. Any appreciate any and all comments and suggestions. Besides, I am sure we are not the only ones reading this thread so all the info will help others as well.
James
James,
Here’s my personal thoughts/experiences and they are sure to clash with others…
Personally, I’ve never heard of anyone’s hobby booth exploding. Heard lotsa talk, but never heard of it happening. Not to say that it hasn’t, so you have to make your own call. If someone has experienced this, please share the story…
I’m no techno expert, but I think the ‘spark’ hazzard has to do with when the fan is either powered up or down. If you power up the fan before you spray, and let it run aftwerwards, then it may not be a real issue. I really don’t know for sure though, so maybe someone else will provide better info.
Personally, I had three muffin fans in my booth (larger than computer fans, they were about 5" square) and I never had any problems. Maybe I was flirting with death… I have no idea. I would routinely spray straight lacquer thinner through my brush for cleaning and didn’t have any problems.
That all said, maybe I’m extremely lucky ?? (Knocking on head now…)
Murray
The whole reason spray booths were put into industrial environments were for the prevention of fires and explosions due to the high concentration of flammable/combustible vapors accumulating in a work space over time. But this brings us back around to the frequency/duration issue. Most industrial booths are for the high-volume paint guns and rattle-cans that are being used for several hours a day. Fires occur because vapor-air concentrations are at their best, and then when you introduce an ignition source…well, you get the picture. Paint residues accumulating on fans, filters, and booth sides is also an issue; that’s why booth construction should not be out of wood. Fires are contained better in metal structures. Based on the fact you are just airbrushing, and that your frequency/duration is minimal (compared with an equivalent industrial day), you could probably get away with a sparking fan, provided you are moving enough air to keep vapor concentrations at a minimum–which they should be. But keep in mind that you still have to have a fan capable of moving enough air to remove the vapors you are creating, and in addition, push them through a length of duct to the outside. I’m not going to suggest a 1,000cfm fan, but I DO think that a 180cfm range hood is not enough to effectively accomplish what you want to do with the size of the booth you want to do it in. Personally, I would not look at anything less than about 400-500cfm. That will give you an average of 50 fpm at the face, and should adequately move most of your paint vapors. You should also do what is necessary to keep your exhaust ducting as short and with as few bends as possible. There is still going to be a big static pressure fall-off on the exhaust side of the fan, and you need to push out what you sucked up. Short ductwork and a straight exit will help with that effort, and will prevent vapor accumulation inside the duct…which could be more of a problem with a sparking fan than just exhausting vapors past it. The duct should also be as horizontal as possible (not vertical), and not be constructed of such combustible stuff as dryer hose. Lastly, for the fan to work at its most efficient, it needs to be positioned at the back of the booth. If you mount it on top, a small baffle hung inside the booth will help to even out the airflow.
Murray may have a point. It may be even more efficient to have a multi-fan setup instead of a single fan. The necessity for good CFM still doesn’t change, however.
You’ll probably be OK unless you pull out several rattle cans and start using them 8 hours a day…in which case we need to have a talk about booth design…
James, you’ve got the option of venting a room (the cheap, easy way to go), and the option of building a booth. If you go with a booth, make sure you inspect and clean it regularly…and keep a fire extinguisher nearby as a measure of protection, and you should be OK.
Let us know what you decide to do. This is a learning experience for us, as well!
Gip Winecoff
PS Excuse me, but I have to go knock on Murray’s head…
Gip, you definitely sound like you know what you’re talking about. I agree with everything you’ve written (not that that’s woth anything…). And highlight one thing that you said… plastic flexible dryer vent hose is a KILLER for airflow. At a minimum use the flexible aluminum stuff (i don’t know what it costs, but it’s pretty cheap), but preferrably solid aluminum vent. Otherwise, your fan investment is just useless.
Why’s my head getting sore??
Murray
Thanks again guys! Yeah, I think I will go with the original set up, and add a large exhaust fan in the window of my modelling room too. And I like the aluminum ducting suggestion. Much better than the cheap dryer vent stuff. And I will definately check all of it often and keep it all clean.
James [:)]