Yes Yet Another Dust Collection Topic

[KCollins]

I didn't want to steal either RFGuy's or ChrisNeilan's OPs regarding Dust Collection and my questions differ from theirs.

I currently have an old HF 4" DC. It worked well with my old tools but now that I have switched over to SS all the ports are 1-1/2".

I wonder if anyone here uses the HF DC on their tools and how do you have them hooked up? I've heard you loose air flow going from a large hose to a small hose.

I also wonder who hear has used the SS DC3300 DC. Does it work well with the SS tools? Is there good airflow? Does it ever clog?

And if by some miracle someone on here has used both please give me your opinion as to which one is better. And why?

And last but not least does anyone know the CFM for either DC?

Thanks

Kevin

[algale]

I use a DC3300 with the 42" hood. Shopsmith claims 330 cfm. By the way the DC3300 takes 2.5" hoses, not 1.5". The Mark 7, 520 and 510 lower saw guard all work with 2.5 hoses as do all the current iterations of those SPTs that come with dust ports.

Does it work with Shopsmith tools? The answer is yes -- sort of. It collects all the dust that is exhausted through the lower saw guard or the SPT ports but the lower saw guard and SPT ports are only so-so. The table saw is the biggest offender where there are lots of gaps between the table and the lower saw guard. Many of us have rigged up stuff to plug those gaps, which can help. The bandsaw is another offender. Open it up and there is usually quite a collection of saw dust in the various cavities in the casting.

On the plus side, I've never had a clog in the DC3300.

[RFGuy]

It depends on which HF model that you have...I believe they had a 1.5HP model previously and now sell a 2HP model. The newer 2HP model is rated at 1000CFM compared to 330CFM on the Shopsmith DC-3300. The Shopsmith unit only has a 0.5HP motor. So, the HF DC should flow at least 2-3x the air that the DC-3300 can. However, this is really only important if you plan on putting in ducting to tools, i.e. a large CFM rating on the dust collector is meant to breathe through shop ductwork and overcome static pressure losses in it. The 330CFM from the Shopsmith DC-3300 is mostly adequate for dust collection with a short hose connected directly to one tool at a time (provided filter isn't overloaded, etc.). Where both fall short, in my opinion, is that they come with filter hoods instead of HEPA cartridge filters. I believe the HF filter hood is rated for 5micron, but many HF owners replace the filter hood with a Wynn HEPA cartridge filter (https://wynnenv.com/woodworking-filters ... ollectors/). On the Shopsmith DC-3300, the 12" hood filters down to 7micron particle size, the 24" hood down to 5micron and the 42" hood down to 1um. In comparison, a good HEPA cartridge filter typically filters down to 0.3um particle size which is the dust of most concern for damaging your lungs.

IF you don't already own a DC-3300, I wouldn't recommend going with it now. I would keep your HF DC. However, if you must buy from Shopsmith, then perhaps wait and check out their new DC-6000 model instead. One note of caution on the DC-3300 is that it can leak dust back into the shop. The motor and impeller housing are all inside of the dust collector. In taking it apart for cleaning, etc., it can easily start leaking dust so you may need to put some weatherstripping in select spots inside it to stop dust from leaking out of the unit. One benefit to having the higher airflow on the HF DC is that you have margin to install a cyclone in front of it, e.g. Oneida Super Dust Deputy or similar. I wouldn't advise putting a cyclone in front of the DC-3300 because you'll lose too much airflow to the cyclone. With a cyclone in front of the HF DC, your filters will last much longer and require less maintenance.

[KCollins]

I'd like to keep my HF if possible and it is the 2hp by the way. It worked well for my old tools. But I attached the DC to each individual tool when I used them. I don't have a duct system. I'd like to put up a duct system but am reluctant because I've read you lose air flow and they clog up. I have also read that going from the 4" hose down to a 2.5" hose will choke off the DC unless you make the smaller hose run as short as possible. I have seen that waynn filter too. I plan to buy it if I keep the HF... Sounds like that would be the better route to go.

[RFGuy]

I'd like to keep my HF if possible and it is the 2hp by the way. It worked well for my old tools. But I attached the DC to each individual tool when I used them. I don't have a duct system. I'd like to put up a duct system but am reluctant because I've read you lose air flow and they clog up. I have also read that going from the 4" hose down to a 2.5" hose will choke off the DC unless you make the smaller hose run as short as possible. I have seen that waynn filter too. I plan to buy it if I keep the HF... Sounds like that would be the better route to go.

Kevin,

Most woodworking power tools need around 350-400CFM for good dust collection. Some (like large format planers or jointers) need double that. In general the higher the airflow (CFM), the better fine dust collection - meaning that more airflow typically helps your capture rate from the tool. The 350CFM number is no coincidence. It comes from the fact that for ducting or hose runs, dust particles stay suspended in the airflow at 4000fpm (feet per minute) or faster. When the speed of the airflow drops below 4000fpm, you "may" have dust start to settle in the ductwork or hoses which can be a maintenance headache. The airflow formula for ductwork is

CFM = FPM x Duct Cross Sectional Area

For 4" ducting/hoses, 350CFM equates to 4000FPM airflow speed.

This is why, I say the DC-3300 is capable of "mostly" meeting the needs of Shopsmith equipment (assuming filter is not clogged, etc.), if you use short hoses and connect one tool at a time (still wish the filter was a HEPA cartridge). Your HF DC should have more than enough airflow to support your Shopsmith equipment. If you want to duct it you should be fine as long as you properly size the ducting (to maintain 4000fpm) and use blast gates at each tool. Using a 2.5" hose instead of a 4" hose will choke off your DC somewhat and reduce airflow because of the smaller aperture, so preference would be to run 4" hose to the Mark V and then reducing at the saw guard if you can. Also, some hoses are lower loss than others. I ordered a 10' 2.5" hose from Oneida that works great and has lower losses (measured) than my Shopsmith hoses.

[edma194]

I have an old Reliant 2HP collector. I think this is basically what the Harbor Freight 2HP dust collector is. I run it with a HEPA bag over the regular cloth bag but I think that restricts air flow a lot, and it was originally made for two cloth bags so I'm always afraid I'll blow out a plastic bag on the bottom. I have a big trashcan separator in front because I vacuum up anything with this and don't want heavy stuff going through the impellor.

My plan that I want to put in place soon is to enclose the whole double bag stack in an enclosure that vents outdoors. I want to get this going soon because I'm starting to make sawdust now that my machines are in half decent shape. The plan is to use foam insulation boards to make a simple box a little more than 2ft. on a side and 6ft. tall that covers the bag stack. It will have a pair of removable panels to change the bags. I'll use an 8" hose to vent to vent this outside. As far as I can tell getting the air out of the house is the only way to get rid of all the dangerous dust because even the best filters will let the very harmful smallest particles get through. This way I can just use a pair of simple cloth bags.

Just a note on these and the HF 2HP, they can be wired for 110V or 220V. 220V gives you no more power but will reduce the current load. This thing can trip a touchy 110V breaker, and I'm probably going to re-wire it to 220V soon. More details on that to follow.