Jet Dust Collector (yes Or No) ???

[Uncle Cracker]

Can't speak to the canister, because I've never used one. That, however, is a hint, as my 50-760 works well enough that I've never needed a canister. As for caking inside the bag, I just give it a whack every month or so, and most of what is caked just drops into the plastic debris bag. I have not noticed any reduction in performance prior to "de-caking", so I'm guessing some allowance has been made in engineering the unit to assure that adequate airflow can be maintained through a partially clogged bag. As for a totally choked one, I'm sure there could be an issue, but there is simply no reason one would let it get that way.

[Turaj]

Can't speak to the canister, because I've never used one. That, however, is a hint, as my 50-760 works well enough that I've never needed a canister. As for caking inside the bag, I just give it a whack every month or so, and most of what is caked just drops into the plastic debris bag. I have not noticed any reduction in performance prior to "de-caking", so I'm guessing some allowance has been made in engineering the unit to assure that adequate airflow can be maintained through a partially clogged bag. As for a totally choked one, I'm sure there could be an issue, but there is simply no reason one would let it get that way.

All he said I think the 1 micron rating an Delta is not dependant on the cake! In fact I've not noticed any difference before or after "de-caking"!! (love that word).

[LCHIEN]

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I really don't know how the bag compares to a cart. filter in the real world. I have read that the 1-micron spec. assumes a cake on the bag, which would reduce airflow. Cart. filters can plug quite easily unless you take appropriate measures.

My point wasn't to say the Jet is better, but just to provide more of an apples to apples comparison in terms of price.

Does anyone know the answer to cgallery's statement? Does the 1-micron spec assume cake on the bag? I am considering the Delta 50-760 because of the cfm rating and the positive review in FWW. But does a canister provide a more consistent filter? Does it provide 1 micron all the time?

from what I've read, the bag filters are prorous when clean and can pass particles bigger than their filter spec, but after a while they build up a cake which is vital to filtering to the spec.

OTOH the CFM specs for these machines is with clean (or no bags at all) e.g. best conditions, and CFM starts falling rapidly with caking. The fact is, with two filter bags as opposed to one bag and a plastic bag the air flow is greatest, but when the lower bag starts to fill it will lose its ability to pass air.

The canister or cartridges, because of the pleated filter, have more than 10 times the effective filter area and pass air more readily than the one or two filter bags. The pleated filter is more effective than the woven fabric filter bags and filter to the spec when clean or used. Using the cart on top gives more filter area, less resistance thus higher CFMS and still allows you to use a plastic catch bag for easier clean up.

In short a 2 filter bag system passes more air when new but filters terribly, and when used, and /or the lower bag fills filters OK but has significant drop in CFM.

A 1 filter bag plus plastic catch bag is not as good as that.

A cart plus plastic bag, gives the most CFM, plus more or less more constant performance as the catch bag fills. this is of course with modet mainteance, knocking the chips and dust off the filter periodically.

I'm not sure how one (e.g. one of us typcial users) can measure actual 1 micron filtering performance, caked vs. decaked; these particles are hard to see and count unless you had the particulate counter people were buying as a group here earlier this year.

for the OP, the HF 2HP DC has proved in more than one actual CFM tests in magazine reviews not to be too great a performer compared to even 1.5 HP models. if that price was for a used unit, compare to prices on Amazon and elsewhere.

[gettools]

thanks for all of your opinions. I ended up ordering the wynn cartridge filter, a 10ft hose & clamps $196.50 I will keep my hf unit. Now I have money left for a new jig saw ( hee hee ) This sight is great, THanks again to all who helped make my decision easier.