How safe is it to hang out/work/be always in (when not sleeping or cooking or whatever) the same room as the LR4 when you’re cutting MDF? My office where I do…everything…is 10 ft. x 10 ft. I wear hearing protection, and I know have a cyclone dust separator mated to a new DeWalt Stealthsonic shop vac, with both a bag and a filter in it. I’m not seeing much dust at all. There is a slight smell after cutting MDF that I think is the wood fibers? But who knows maybe it’s formaldehyde!!
Anyways I went looking for official advice on the material safety and handling sheets from manufacturers but they don’t really cover this use case, it’s mostly about fire prevention and stuff. I was thinking someone here may already know it’s safe and/or is a bad idea. Thx!
If you can smell it, it’s made it past your coarse filter (i.e. nose hairs) and is inside your body whether it’s big enough to see or not. Check out the size chart here for broad strokes sizes. The really fine dust - “respirable particles” in the linked chart - is what can get in your lungs and stay there. If you want to keep that out you can invest in an air quality meter to read the level of the tiny particles (maybe 0.3 microns?) that will make it into your lungs eventually, then build an air scrubber that turns around the air in your room however many times per minute, or you can invest in appropriate personally worn filters and respirators for the particle size you’re worried about and be sure you’re keeping it out as long as they’re sealing well against your face. Both of these approaches rely on consumables that will need to be replaced on an appropriate schedule to maintain the protection.
This is what I needed, thank you both. Where do you all cut MDF, just…outside? In extremely well ventilated spaces like garages or whatever that you can more easily clean? I’m so glad I asked, I really appreciate you both taking the time @MakerJim and @ttraband!
I’m in a very “do as I say, not as I do” situation with a basement shop. I do have a dust collector with a chip separator (“thien baffle”) and .5 micron filter. I’ve got a plan to build an air scrubber but haven’t been doing as much sawdust generating lately so it’s sort of stalled on the “back burner projects” list. I still try not to cut too much mdf indoors. I’ll break big sheets down in the driveway or garage before schlepping stuff downstairs for fine work.
https://www.billpentz.com/ is a rabbit hole you can explore if you want to dive deep into dust collection. One of the big goals should be to do your best to catch the dust at the source, before it gets diffused through the air you’re breathing.
I know it’s probably too little too late, and I won’t do any more cuts in here, but I have HEPA filter I’m now running in here based on your comments. That seems spot on for 0.3 microns based on the spec, so I’ll just run it in here overnight with the fan on to try and circulate and clear whatever is left.
My read is that the damage is cumulative, so one day probably won’t be enough to cause lasting harm. Anything you can do to avoid breathing it in is better than nothing!
Another hint to how effective the filter is being is whether you come back in the morning to a layer of fine dust on surfaces. Any dust on the desktop is dust the filter didn’t manage to grab.
I think I probably just won’t cut MDF with this thing any longer once these strut plates are done . I did stumble across this Corsi–Rosenthal Box - Wikipedia which seems really promising for small space filtering of really, really tiny stuff. I might make one to run in here anyways, it seems like dust is just…bad. Even if it’s not VOCs like what MDF gives off.
MDF is just nasty and I really don’t like it as a material.
I have an air filter in my shop (an old dust hood) that I use when sanding wood or cutting MDF combined with a mask. I still have around 2000 masks that I got from my school after the pandemy had ended.
All wood dust is bad for breathing though, not just mdf.
What do you wear when you’re sanding? I use a mask and I open the garage door. Almost every commercial woodworking space I’ve seen (including at the local schools) has a big air filter hanging from the ceiling. A long time ago, I saw a lot of youtubers (like Jay Bates) had made one from furnace air filters and a squirrel fan.
Generally speaking I don’t do any of my other woodworking inside. This is the first time I’ve had a robot that I can’t easily haul in and out, which really amplifies my need for a dedicated and well-ventilated space. Alas.
I always take woodworking out to my back deck. I recently got a 3m respirator mask with the pink filters to wear when doing high-dust stuff, before I’d just wear an N95 mask leftover from COVID-19 (I have 100s). But I got the 3M mask because I’m going to be working with mineral wool and refractory cement and rigidizer, so I’ll probably use it for everything now.
That WEN unit is surprisingly affordable, probably only $50 more than those Corsi-Rosenthal boxes I linked up thread. Thanks for sending it!
Just to be clear, I did not vet it. I was just looking for an example. I don’t see anything wrong with it either. There are dewalt versions for less than $200 too.
That’s what I mean when I say an “air scrubber.” You try to capture the dust at the point at which it is created, but you can never get it all, so in addition you have a high volume fan designed to move all the air in the space through a filter, something like 6 times an hour, in hopes of catching the little ones that got away.
One of the challenges with the low rider is that it’s size makes it difficult to fully enclose so you can filter just that volume of space.
. I did stumble across this 
. Thank you for linking this!