djscruggs wrote:many have suggested "just using a shopvac". Mine adequately picks up chips...but to clear the air of dust, do you have to just let it run for a certain period of time during and after using the machines?
There are no right or wrong answers, per se, when it comes to dust collection for a woodworking shop, other than you must do something for dust collection. However, there are pros and cons depending on which system you buy and how well it fits your particular shop and the type of woodworking you do. Let us know what you decide on and how well it works for you, or if you have any other questions. I have done a significant amount of research on dust collectors and tried to share that info in my post, but I think we are all learning when it comes to dust collection and I am open to feedback on this. The perils of breathing in a high dust environment can be quite severe and the effects are cumulative. When I started woodworking 3 decades ago, I think most of us were in the dark when it comes to dust collection and I certainly did my share of woodworking without dust masks, etc. when sanding in particular (at times it was like working in the Sahara in the middle of a sand storm). Now there is more widespread information out there for all of us. What is really great now is that there are affordable air quality monitors like the Dylos DC1100 so you can directly measure the particle counts in your shop.
Online, I see a lot of people start out in woodworking; they buy the HF unit...some hack it by putting a larger blower fan (impeller) on it, most add a Super Dust Deputy Cyclone in front of it, many swap out the filter bag for a Wynn cartridge (HEPA) filter. Often times after many years of solid use, they will upgrade from the HF unit to a complete commercial DC with integrated cyclone. The challenge for a small shop like mine, or an even smaller shop like yours is getting "good enough" dust collection without copying the DC designs of much larger, or even commercial level, shops (added expense and noise). DC's have to be properly sized to the shop and the ducting for it; similar to how HVAC ducting has to be properly sized and matched to the HVAC equipment. More ductwork adds more static pressure loss to a DC system, as does smaller duct versus larger duct. With smaller shops like ours, if you even do duct work it could be overkill to size over 4" PVC - the higher CFM DC's are only needed to move more air down a larger duct. If you can get away with direct tool connection and no ducting, then a large DC is overkill. Remember it is all about having a fast enough air stream at the tool dust port so that it captures nearly 100% of the dust and the large dust particles and wood chips don't fall out of the air stream and clog the line. Keep in mind that all Shopsmith equipment is designed for a single 2 1/4" dust port hookup, so this limits the airflow significantly. Unless you hack the ports on all the equipment, the min airflow needed is only 136 CFM at the port assuming the minimum 4000ft/min needed and the area of the port (FPM=CFM/duct area). So, purchasing a 1000CFM DC is way overkill for a Shopsmith, UNLESS you have significant ducting in your shop and/or are running multiple tools at once. Of course having more capacity is a good thing and the 2 1/4" port will flow more air up to a point, but I don't know how much more actual airflow you'll get through a 2 1/4" opening with a larger DC. Probably doubtful you'll see the 400-800cfm a lot of people claim is needed at a tablesaw/planer or jointer for instance. This is why all woodworking tools (other than Shopsmith) put 4" or larger dust ports on their tools now. Shopsmith has kept the legacy 2 1/4" ports unfortunately which are very restrictive to airflow.
For me, for now, I can live with a Shopvac, but it requires running a HEPA bag and HEPA filter on it AND a cyclone in front of it so it doesn't quickly clog up, i.e. airflow stays high. Downside to it, is I really can't let it run for say an hour while sanding a woodturning. Shopvacs are made to turn on, for maybe 5 minutes and turn off. They will overheat and thermal limit, whereas a dedicated DC is meant for continuous duty. Some day, when I can afford it, I will get a large cyclone DC and mount it outside my shop. It will be overkill for my Shopsmith and needs, BUT it will be needed somewhat to maintain the required airflow over the length of duct, especially the verticals that I intend to install. It is a "want" and a "nice to have", but I can't afford it at this time. My DC3300 was insufficient for me, but the Shopvac+cyclone has made a world of difference in my shop, but it has limitations.
Sorry for all of that, but just wanted to make sure that I clarified a few points from my previous thread. Now, to answer your new question. Yes, you will need some alternative air cleaner in addition to the DC. In an ideal world if you have good dust capture at every tool and a good dust collector with excellent exhaust filter, then you would NEVER need an air cleaner. We do NOT live in an ideal world.
I have a JDS Airtech 2000 hanging from my ceiling. There are lots of other brands out there, Jet, Powermatic, etc., etc. These go for around $300 or more. Basically just a good quality filter(s) with a squirrel cage blower in it to scrub the air. If you can fit one of these great, but if not an alternative and cheap solution is to go buy a $20 box fan from anywhere and get a pleated paper air filter (like you get for HVAC system). Buy a good size to fit the box fan and attach it to the inlet side of the box fan (bungee cords or however you want to attach it). Running this in the background all the time will scrub the air and can quickly get better air quality in your shop. You really can't use the Shopvac for this because it has a small air inlet which means it would take a long time to cycle the air in the shop, but you can't run a Shopvac all the time either or it's teeny tiny motor would burn up. Larger DC's can do a similar function if you leave one port open to suck in shop air to clean it, but it takes them a much longer time to cycle the air than a JDS, Jet, etc. air cleaner. Bottomline is for sanding in the shop (hand or power tool), you really need an air cleaner in addition to a DC. Unless you are running a Festool sander with a Festool vacuum, just about any variation of sanding will introduce significant dust into your shop and you can only capture so much of it with a DC. An air cleaner is a must IMHO, but presents another challenge in trying to fit it into your small shop...can you mount one on your ceiling or is the basement ceiling short?