It’s getting cold in Boston and venting to outside is not an option for my shop, which is expensive to keep warm and I don’t want to be sucking cold make up air inside. I’ve been looking through the affordable extraction units that vent inside and could get one with the articulating input, sticking it near the action. Another thought is to build my own. I could just buy the filters that claim 99.997, which is good enough for me.
I’m curious if there is another option for the actual collection, like a base with a 6 or 8" hole under it, where I’d go through the QCW. This would get everything from under the honeycomb. Still thinking through ideas about perimeter collection for grabbing the top smoke. PS, this is for cutting and engraving.
Do you have a cool solution that eliminates most of the foul smoke and smell?
I get free stuff from Amazon to review. One of them was a 210w fume extractor. I don’t think I would buy one simply because making one would be extremely easy. It’s just a square box with a series of stacked filters. With some plywood one could build the same thing. As long as you use a static pressure gauge you could even use a shop vac for the pump.
The one I got has a remote, timer feature, and LCD display that’s sort of nice but not needed. I have it set up so it plugs into the same outlet that my dust collector plugs into. Once the job is over the controller turns off a relay that shuts off the outlet.
A static pressure gauge will measure how clogged the filters are. A shop vac’s motor requires airflow to keep it from overheating. Depending on the shop vac you use that air flow could come from air it’s sucking up. A clogged filter could reduce the air flow too much. In general having a gauge will help you judge the condition of the filters.
Hey, I totally get the cold shop issue in Boston! Using an articulating input near the action is a great idea. As for building your own, high-quality filters that capture 99.997% of particles should work well. For collecting fumes from under the honeycomb, a base with a large hole sounds promising. You might also want to check out some fume extraction systems designed for laser cutting and engraving—VentXLabs has some solid options.
Looks good but I’d move the blower closer to the exhaust outlet next to the window. The shortest distance between the blower & the exhaust, the less likely you’ll experience any laser smoke/fumes as the negative pressure won’t leak at connections, pinholes in the hose, etc. The only part under positive pressure will be the short section between the blower & the exhaust (positive pressure will “push” fumes and if you have any leaks the fumes will come out).
Good suggestion on moving the blower closer to the exhaust. That definitely makes sense to reduce the chance of leaks and maintain strong suction. One thing I’m wondering though: when placing the blower closer to the exhaust, could that increase the airflow too much, or put unnecessary strain on the blower over time? Curious if anyone has experience with this setup and how it performs in the long run.
Nope. The opposite is actually the case - more restrictive hose increases strain on the blower motor and reduces airflow. They’re rated (CFM) in an unrestricted installation where there is no hose attached on either side. But they’re designed to have hoses attached so you’ll see lower airflow/CFM then rated but not issues with overworking the motor except in extreme situations. The shorter the exhaust path, the easier it is on the motor because there’s less back pressure to overcome.
In reality, you have to go to extremes to affect the motor (like putting it on the bottom of a 30 foot hose that goes up to the roof to exhaust). The type of hose and number of bends also has an impact - every 90 degree bend is equivalent to 10ft of hose (there are calculators out there used by HVAC folks that can calculate the resistance in a hose or piping installation). Smooth walled pipe like sheet metal or PVC has less resistance than the expandable accordion hose we typically use for this.
In practice we’ll never affect the motor. I’ve had mine running off my laser for over 10 years without any issues.
