The Lacquer curing thread brought up an issue for me I figured I would put in a separate thread.
How do those of you who have Lacquer curing for long periods handle the fumes?
I am considering building some sort of off gassing cabinet, (bomb?) that trickles air slowly out side.
Like many small shops I'm sure, I apply lacquer touchups in front of a large explosion proof fan that vents out side, using the shop air as make up air but dumping out precious heat and Humidity. A few shops I've worked in simply fire up the big spray booth fan periodically during the initial drying to alleviate curing fumes but it always leaves some amount in the air that is not good and having a cold and/ or dry shop was not a problem.
Do any of you have a system for handling this? Do your spray booths have a smaller fan that keeps them slightly venting out even when not spraying?
I have been thinking for some time about a small curing space that could hold instruments for the weeks they are gassing off but insure that air is not backing up into the shop. Either with a tiny fan or one way vent system.
Obviously safety is the goal and blowing myself up to spare my central nervous system and liver would be counter productive.
Research activated charcoal cartridge air filters. The 6-8" cartridges connected to an aux duct fan sized to ~8 air exchanges/hr will absorb volatiles. These can also be used to absorb volatiles from illegal houseplants so if you have a local indoor growing/hydroponic shop you can see some of the ready to use systems. The components can be found on Amazon and connected easily for much less money. If you're considering a small closet you can fab a system like this: http://www.instructables.com/id/Activated-Carbon-Air-Filter/
Interesting Idea Mark. Thanks!
I'll try and figure out charcoal use cost.
what if the charcoal gets saturated and fumes hit a spark in the fan? I have to figure the minimum explosive concentration too.
No need for plant filtration here in Colorado.
The big cartridges are refillable and activated charcoal granules are cheap in the Aquarium section of your nearest superstore. The rating on the filters is for a year and considering this is being used for off-gassing and not spray booth use, the filters should last a long time. If you are using a small enclosure within a room and entrain room air/exhaust filtered air back into the room you'll be safe from explosions. Your nose will let you know well before the charcoal is nearing its saturation.
I really like this Idea.
I think I'm going to pursue it. I guess putting the fan pushing on the upstream side would work. Do you have some experience with something like this? From a related field? or are you just brain storming with me? I appreciate your input.
I made a one of these for a friend with a Laser cutter/etcher to deal with smoke and byproducts from wood, plastics and metals and it has worked well. The weak point in the system are the fan bearings. As far as my background, I worked in the Medical Device industry in Anesthesia/Respiratory gas conditioning/filtering products and on the clinical side in Occupational Health among other things.
I hear your concern for fire/explosion risk but if you are not in a production situation, the quantity of volatiles with one or two acoustics off-gassing in a corner of your shop, spare bathroom or bedroom is pretty small. They would need to be in a very small airtight enclosure to even get close to a dangerous level.
Again, your nose knows. It is very sensitive and you pick up the scent of toluene at 8ppm. Alarm levels start at 100ppm for 10hr/day 40 hrs/week exposure and 250ppm for 8hr/day 40hr/week. Acetone scent threshold is 20ppm with alarm levels starting at 750ppm over an 8 hr/day, 40hrs/week period. So, all of this to say that if you don't smell acetone or toluene in a storage room/closet with off-gassing Nitro finished guitars and you're running one of the charcoal cartridge filters, you're safe from an exposure and fire/explosion standpoint.
If you do go with a closet/cabinet and use an externally mounted fan pushing fresh air in and contaminated air out through a charcoal filter, you have to seal any leaks to force the air under positive pressure through the filter. Having a more open system under a negative pressure (ie the filter is mounted between the cabinet and the fan) depends on leaks for fresh make-up air and create a dilute atmosphere in the enclosure.
Thanks again mark.
This is really helpful information. Hopefully this will help move the project off the, " things I really should do" list.
I'm guessing a lot of shops have this issue.
I want to remove any, "my work space is bad for me" nagging that goes on in my head if I can.
Even though Lacquer is still a kind of miracle finish for many reasons, I often wish we could end it legally like Asbestos. Time to move on and tell customers I'm not allowed to use it any more.