Jet 1 1/5 HP 1100 vs. Grizzly 2hp dust collectors

[whit richardson]

I've been shopping for a dust collector, (please Santa!) and my other woodworking buddies said go with the Grizzly 2hp for less than the Delta or Jet. We're talking Canister since I decided <10 microns is way better.

Today Grizzly 2hp is $425 w/ shipping and Jet is usually $649 (why?)

So I found a new Jet 1 1/5HP that I could get for maybe under $400 so opinions? Good deal anyway?

I'll be using this for a Delta Unisaw, Dewalt DW735 planer, Dewalt 10" miter saw, my router table (farside of the tablesaw w/ lift) for now, maybe a 14" bandsaw down the road. Folks always want to know the application.

[Lance Norris]

Whit... obviously, any dust collector is better than none. I have the Grizzly canister(G0548)and Im sure the Jet is just as good of a machine. I have both Grizzly and Jet machines and both offer quality equipment. I know this doesnt give you the answer you were looking for, but Im sure you cant go wrong with either. Consider also that the Grizzly is 220v and I think the Jet is 110v. Might be something to think about.

[glenn bradley]

I would go with the 2HP or the few dollars.

[whit richardson]

Thanks. Yes after looking at the Grizzly the downside is having to have another 220v installed in the shop area (garage shop). Upside is I have a friend who does that as a business. I still have to pay but get a good job at good price.

[Lance Norris]

Well then, if the 220v circuit isnt a problem, I would recommend the Grizzly, because I have one and its a fine machine. I think for a canister DC you cant beat it. It has all the power you will need, for a home shop. You might want to consider opening up the ports on your Uni, or adding a second dc hose into the cabinet because a single 4" port isnt enough. Here is a thread I started when I modified mine:

http://www.sawmillcreek.org/showthread.php?t=76571

[Herbert Wallace]

I am buying a DC system this week. I have been reading all the posts on this forum, now I am more confused than when I started. I have learned
that sawdudt is far more dangerous than neuclear fallout. How I have survived breathing the stuff for 64 years is only by the grace of God. Bag collectors vs cyclones. What is the truth and what will work efficiently without breaking the bank? I had my mind made up to buy the Griz 0458 3 hp. which is $395. now I read here that the 2 hp. 0548 @ $425 works great. what is the difference? I would expect to pay more for the 3 hp.
I have a 35' x50' shop with TS,BS,belt sander jointer drill press 12" bellsaw 5hp planer, 13' Ridgid plNER 10' slide miter saw and a 10' RAS. I plan to vent outside. any suggestions and advice would be appreciated. Further confusion will also be accepted.

[whit richardson]

I am buying a DC system this week. I have been reading all the posts on this forum, now I am more confused than when I started. I have learned
that sawdudt is far more dangerous than neuclear fallout. How I have survived breathing the stuff for 64 years is only by the grace of God. Bag collectors vs cyclones. What is the truth and what will work efficiently without breaking the bank? I had my mind made up to buy the Griz 0458 3 hp. which is $395. now I read here that the 2 hp. 0548 @ $425 works great. what is the difference? I would expect to pay more for the 3 hp.
I have a 35' x50' shop with TS,BS,belt sander jointer drill press 12" bellsaw 5hp planer, 13' Ridgid plNER 10' slide miter saw and a 10' RAS. I plan to vent outside. any suggestions and advice would be appreciated. Further confusion will also be accepted.

That is confusing! Also a Grizzly 3hp less than the 2hp? I checked the DC's and here's the deal the 3hp your'e looking at is a 30 micron filter while the 2hp is a canister capturing down to 1 micron. So you are getting much finer filtering and a lot easier cleaning of the canister.

I too have been without a DC but I mostly worked with plywood, pine, oaks, OSB and such in an open garage shop. Getting into woods like Walnut, Bubing, etc. with power tools you run more risk of fine dust particles getting into the lungs and creating respiratory problems. The woodworkers of old couldn't create the kind of dust we do on our newer power tools today. Also industrial worker of 100 yrs past didn't get any care if they had health problems from the cabinet shop or coal mine. They just died younger.

All in all I see that a decent DC running at plus 1000 CFM and catching >5 microns should handle a typical hobby woodworker. I'm just thinking maybe a can get a steal on the Jet, if not I'll buy the Grizzly 2hp.

[scott spencer]

Jet and Griz should be roughly comparable quality. If all else is equal, more HP should mean a bit more more airflow. Check the size of the impellers, the mic rating of the filters, etc. The airflow specs tend to not be overly useful, but many of the other specs will give you some clue.

220v is likely something you'll want to do eventually, so I'd go with higher HP.

[Scott Myers]

Ahh. The ever confusing area of dust collection. I don't want to turn this into a cyclone VS bag VS canister VS trash can separator, VS whatever thread. You question is innocent enough.

In the area of CFM VS HP: I advise ignoring any claims to the amount of CFM. Just go on HP. More HP = more CFM... period. Canisters allow more CFM than bags due to greater surface area with the same HP... period. Cyclones don't move enough air at the tool until you get to 3 HP... period. The best dust collector won't work that well with 4" hoses... period. Other than these basic "rules", the rest is open to debate.

IMHO - Don't go with anything less than 2 HP. Don't scrimp on your dust collector. I did to some degree, and I now regret it. I have the 2 HP Grizzly and wish I would have went with the three. It's a well built machine, but I would have liked more air flow. I have a small home shop and run just one tool at a time.

Make sure that the dust collector you choose has a dynamically balanced steel impeller, NOT ALUMINUM. Aluminum erodes and is too prone to damage. I know Grizzly uses steel. I don't know about jet. Make sure the impeller housing has no plastic but is all steel.

I would suggest doing some research on what you need. There are a number of sites out there. Bill Pentz has some pretty good information on his site for what tools require what air flows according to OSHA, Euro, ANSI, etc. Don't take everything he says as gospel, but it's some pretty good info.
http://www.sawmillcreek.org/newreply.php?do=newreply&noquote=1&p=984934

Good luck.

[Herbert Wallace]

Thanks for the straight talk , guys. If I vent outside, filters and bags aren't necessary, correct? In this case, hp. rules right? no filters to clean etc. I will just blow it all in the hog pen. they should like that. I think they are smart enough not to eat the stuff". So, I should run a 5" pipe down the center and drop down with 4" flex pipe? My planer and band saw have 4" ducts. My spindle sander, belt sander table saw and router table have 2" then, the RAS & CMS have like 1 1/4". I am not going to duct my jointer, just run it in a box. Will standard ABS drain pipe do the job?

[Joel Earl]

Herbert - you tossed a lot of questions out - good ones too. What you'll find is there is no cast in concrete answers. Sometimes that 5" run is the best, sometimes I've found using a 6" and then dropping to 4" is best. It depending on the DC I was attaching to.

So ...... I'll let others chime in.
I'll toss this out FWIW. I've had the 1.5 Jet, the 1.5 Delta, the 1029 Grizz (not Z) and the infamous HF. And today I use the one I personally find to be the best of them in my shop setting. It's the PSI but it's 220v so....
thing is a great unit with excellent bags as shipped. It does all I expect of a DC and then some more. The comments from Wood mags review are referenced in the link.
As they say - another choice. To further confuse it all at that. Good luck!

http://www.pennstateind.com/store/DC2000B.html

[Scott Myers]

Sweet! You can vent outside. Life will be good. The biggest cause of system pressure drop is the filter. Sometimes physics is just against you. Sadly, I do not have that luxury.

If you go through all the velocity rating for largest chip sizes and how the manufacturers rate size of the pipes VS CFM, they shoot for about 4000 FPM, although you really want 4500 FPM to get the largest chips. So if you go through all the math, you will find that 6" is about right for lowest pressure drop and the correct air flow speed (at about 2 HP), assuming a "typical" amount of piping in a small shop running 1 (maybe two, depending) machine at a time. I found several manufacturer agree on these figures, as well as Bill Pentz. At least they can all agree on that much. Just neck the 6" down to 4" right at the machine. Sadly, machine manufacturers only give us 4" ports on the machines. :(

[Herbert Wallace]

Thanks everyone. I just made out my order list for the Griz. G1029 with remote control and all the hoses, blast gates and adapters. total $722.00.
Another $100 bucks or so for pipe and connections and I should be in for less than $ 1000.00. I'll order Monday. A drum sander will be my next buy.
Probably the Griz G0458.

Thanks again and Merry Christmas

[whit richardson]

Gee now what do I do? More HP is great but I also need more $$'s. I need a planer and best deal I find is $499 @ Lowe's on a DW735 so that's a hit in the pocket too. During these times my hobby has to be on a leaner budget as it's not like I sell anything I make right now.

[Rod Sheridan]

In the area of CFM VS HP: I advise ignoring any claims to the amount of CFM. Just go on HP. More HP = more CFM... period. Canisters allow more CFM than bags due to greater surface area with the same HP... period. Cyclones don't move enough air at the tool until you get to 3 HP... period. The best dust collector won't work that well with 4" hoses... period. Other than these basic "rules", the rest is open to debate.

Good luck.

Hi Scott, I'd have to disagree with a couple of your points.

1) The airflow claim for my Oneida cyclone is actually a couple of percent lower than it's measured value in my shop. No need to discount Oneida's claims, they are accurate.

2) My system is the 1.5 HP component system and it is plenty large enough for my shop. It delivers over 400CFM to the cabinet saw base, and over 200 CFM to the overarm guard for the saw. In addition it delivers 600 CFM to Hammer A3-31 planer.

I certainly don't need a 3 HP cyclone, my brother has the 2 HP Commercial which works exceedingly well in his 2,200 sq foot shop.

Regards, Rod.

[Chris Padilla]

In the area of CFM VS HP: I advise ignoring any claims to the amount of CFM. Just go on HP. More HP = more CFM... period. Canisters allow more CFM than bags due to greater surface area with the same HP... period. Cyclones don't move enough air at the tool until you get to 3 HP... period. The best dust collector won't work that well with 4" hoses... period. Other than these basic "rules", the rest is open to debate.

I must also disagree here. In fact, I would IGNORE any HP ratings on a system. Did you know that they all turn at 3450 rpm?

The key is the size of the impeller and the size of your ductwork. Those two items are key to determining airflow at your pickup point.

[Scott Myers]

OK, Chris. You're going to have to explain that one just a WEE bit to me. I think we are really both saying the same thing in a different way and we really are not in disagreement.

Here's how I see it. Larger impellers = more CFM being pushed. Larger impellers = more needed HP. Therefore more CFM being pushed = more HP. It's just physics. No way around it. No elfin magic here. (NOTE: I am assuming a standard impeller design typically found in woodworking DC's.)

The point I was getting at originally (without bringing it up) is different manufacturers have varying claims on CFM. Some are conservative (not many) and give you ratings based upon nominal filter dirt, some pipe pressure drops and the like. Most however give you a flow rating based on what seems to be an open inlet and outlet on their impeller housings, which isn't real world. So it is better to just look at the HP and know that more HP equals more CFM. The optimal impeller designs were worked out years ago and they all use the basic same design, with a few tweaks here and there. (Again, we have to assume that they are using the full potential of the available HP.)

The other issue is that a number of DC manufacturer's don't even tell you the impeller size!!! You have to call them and beg the info. Waht's up with that? I find that a bit annoying, if not somewhat suspicious, IMO. So without that info, you just have to go on HP and current draw.

And yes, I know they all turn at 3450 RPM.

Pipe sizes and other restrictions are the variables that control what you really get in CFM through the system, of course. I agree with you on this totally. But you have to start with the impeller size... and available HP dictates how big of an impeller you can have. I hope we can agree on this. Everything else for max CFM with a given HP (same as given impeller size) is dependent upon total system design. (NOTE: There are some other impeller designs used in the really high flow systems, but these are not typically found in woodworking)


I must also disagree here. In fact, I would IGNORE any HP ratings on a system. Did you know that they all turn at 3450 rpm?

The key is the size of the impeller and the size of your ductwork. Those two items are key to determining airflow at your pickup point.

[chet jamio]

Again, we have to assume that they are using the full potential of the available HP.

That is a bad assumption:
Clear Vue CV1800 has a 15" impeller with a 5hp motor
Grizzly G0440 has a 14.5" impeller with a 2hp motor

From reading the Pentz site, it appears to me that he sizes his motors for a 0" SP condition (no ducts, no filters, and it seems even no cyclone body). This condition is never seen in normal shop use.

I believe that impeller size is a better indication of CFM.

[Scott Myers]

OK. Point taken on diameter. I guess I better REALLY point out every detail. You guys are brutal! ;)

Perhaps a better statement would be to say that the total area of the fins on the rotor along with the housing design and RPM with given inlet and outlet sizes to produce a given amount of CFM is proportional to and will dictate the total HP required. Now that IS an accurate statement! I hope I didn't leave any holes in that one.

Chet, the CFM "capacity" of those impellers IS appropriate for the HP. So looking at the Grizzly G0440 (which is the apparent odd duck), they may be using a thinner cross section or specific housing design which limits fin air resistance to be able to push this large diameter with a 2 HP motor. HOWEVER, they rate this machine at 1354 CFM, so again, this falls right in line with other DC's with a given HP being able to push a certain range of CFM. (2 HP usually is advertised in the 1,200 - 1,500 range)

I don't know where you date came from on the CV 1800. The 1800 has an 18" impeller, which is how the model numbers are decided with Clear View. However, I will say that Clear View gives closer to realistic CFM ratings based on real world about anyone else, with Bill Pentz's charts agreeing. Note that Clear View's data appears to agree with Bill Pentz's data on air flow. http://billpentz.com/woodworking/cyclone/DCBasics.cfm

So again, we are right back my previous statement of "More HP = more CFM... period". So unless someone here can figure out how to break the 1st and 2nd laws of thermodynamics, this statement is true.

Another important point is no manufacturer is going to use any larger of an electric motor than they have to. It would make no sense from a cost standpoint. They will use the minimum required HP to push the air they designed for.

So if you are comparing a Grizzly to a Clearview Cyclone and are looking at each manufacturer's claimed CFM ratings and considering their HP ratings, you better do a reality check when looking at the numbers. The Grizzly 2 HP unit is not going to produce the same CFM as the Clear View 5 HP unit put into the same ductwork system, even though the claimed specifications might lead one to believe the opposite if you are not discerning and don't understand all the specs given. You've got to take the system as a whole into consideration.

Please, the point is HP is directly proportional to total available CFM. Therefore, impeller size IS NOT a better indicator of CFM, else the Grizzly unit would be putting out a lot more CFM than 1300 or so. But that isn't the case, is it? You don't get something for nothing, else perpetual motion would be possible. Entropy is NOT our friend, but it is proven theory. :D



That is a bad assumption:
Clear Vue CV1800 has a 15" impeller with a 5hp motor
Grizzly G0440 has a 14.5" impeller with a 2hp motor

From reading the Pentz site, it appears to me that he sizes his motors for a 0" SP condition (no ducts, no filters, and it seems even no cyclone body). This condition is never seen in normal shop use.

I believe that impeller size is a better indication of CFM.

[chet jamio]

I don't know where you date came from on the CV 1800. The 1800 has an 18" impeller, which is how the model numbers are decided with Clear View.

The CV1800 is a 18" cyclone which specifies the cyclone body, not the impeller size. The picture shows that is has a "15" Material Handling Impeller".

103194

I did check the claimed CFM ratings for each at 7" SP (small shop with some 6" ductwork):
Clear Vue CV1800 = 1214 CFM
Grizzly G0440 = 900 CFM

These have similar impellers, but different results. It appears HP may be more indicative of performance than impeller size. However, the 250% increase in motor power only gives a 35% increase in CFM (at the selected SP).

[Scott Myers]

Yep, I misread Clear View's web site. It is 15". The info on Clear View seems pretty accurate and agrees with what I would expect.

Yes, you should be suspect that someone's info might not be quite right, as you pointed out a 250% HP increase with only a 35% increase in CFM. Doesn't quite smell right, does it?

[Eric Schniewind]

Check the size of the impellers, the mic rating of the filters, etc. The airflow specs tend to not be overly useful, but many of the other specs will give you some clue.


What happened to the discussion of the micron filter rating? That's what I'm interested in. If you have a higher HP motor pulling more air but it's only capturing up to 2.5 microns, how do you compare with less CFM but a filter that captures up to 1 micron?

[whit richardson]

I'm going to sneak away now and send this link to some industrial design engineers who might find this interesting.... and go buy the Grizzly because somebody sniped me on ebay.

later guys

[Scott Myers]

Whit,

You'll do well with the Grizzy. That is what I run.

Scott

[Scott Myers]

Eric,

Ask a seemingly simple question and you get a ridiculously long winded diatribe, at least from me. :D

Well, you don't compare the two, exactly. The reality is that they are inversely proportional to one another. IN GENERAL, the finer the filtration, the lower the CFM capability. Bummer. Again, physics isn't our friend here. I work with filters in my industry A LOT, mostly for hydraulics. I spec in and sell for air also. But when you get into filters, you SHOULD start talking about efficiency in the form of beta ratios (fluid filtration only) and MERV numbers (air), delta-P, dirt holding capacity, etc. You have to know whether it is surface media or it has some geometry/depth to it (typ: paper VS synthetic/spun glass). I have sold and do sell and spec in Donaldson, Shroeder, Pall, MP Filtri, Argo-Hytos and a number of others. I've had factory training from most of them, for what that is worth.

Let me say that some filtration is better than none, provided you have adequate CFM for what you are doing.

(Taking a deep breath)

I can tell you already suspect that something is amiss in the way these DC's filtration levels are advertised. Something is amiss. Too much marketing, not enough fact. Here are some FACTS when it comes to filter elements.
If you compare two filter elements of the exact same design, but different "micron ratings", the following will be true.
-The finer one will create more pressure drop thus allowing less CFM - period
-The finer one will plug up faster under identical usage - period
-The finer one will protect your health much better (assuming it is properly sized), provided it is maintenanced/replaced as often as it should be - period.

First, you CANNOT compare bag filters with cartridge style. It's like comparing filtering through a piece of toilet paper to a 10 foot thick sponge. Comparing a 2.5 micron bag filter to a 1 micron cartridge filter is, well, ludicrous. Bag filters have some filtration, but they are not really going to give you true 1 or 2.5 micron filtration with any kind of high CFM, unless you have a huge number of them and they have a very thick cake on them (even then it is questionable), as in a bag house. They really work on the cake principle, which works well if undisturbed. But as soon as a cake is built up, your CFM is in the toilet. You knock the cake down, and you CFM comes back up, but your filtration level drops significantly. Bag filters have horrific pressure drops when caked just a bit and TERRIBLE MERV numbers/efficiencies. (Discussed later) I am sure someone will want to jump all over this and make some comments. Don't take my word for it. It's your health. If you want the straight skinny on bags VS cartridge filters, call filter manufacturer that do true R & D and make their own filters and discuss it with them at length. They will send you info and give you enough technical data to make your head explode. So if anyone wants to debate this point, call the filter manufacturers and argue with them. There is a HUGE database on data out there that supports this point. Professionals in the filtration world don't consider a bag filter any more than a "rock catcher". :(

Now for real filters; cartridge filters. The study of them is pretty complex stuff. First, you need to understand that NO FILTER made takes out all particles of a certain size. Say a filter has a "micron rating" of 1. Well, it still will not take out all particles larger than 1 micron. It will take out some percentage. Even a 10 micron rated filter will take out some percentage of particles between 1 & 10 micron. So does a micron rating alone tell us much? Nope. Not really.

About micron ratings. I am not going to go into the REALLY nasty technical stuff, but enough so you get the idea of what you are dealing with. In most cases, I advise you to be suspicious when a manufacturer can only give you a micron rating and nothing else. Saying a filter is 2.5 micron or 1 micron or 1,000 micron doesn't reallly give you usable information. You have to say what the micron rating is based on some efficiency level. You have to consider A LOT more than just the micron rating. Good and reputable filter manufacturers do A LOT of testing on rating filters. (Note that the number of filter manufacturers that do true research and design on the elements themselves number less than 20 or so in the world, yet there are literally hundreds of filter manufacturers. They all copy the good manufacturers and provide far inferior product generally.) In the world of fluid filtration, they go by what are known as beta ratios. In the world of air filtration, MERV numbers will have the most meaning, something you'll not hear many DC manufacturers discuss much. These numbers (beta ratio and MERV) are simply a ratio of the number of a certain measured size particle that exits compared to how many entered the filter. That gives you an efficiency at that micron size. MERV uses a rating system with 16 being the highest/best. But understand that the higher the number and greater the efficiency, the less CFM you can get through it and the faster it will plug without increasing the area of the filter.

So, then we consider pressure drop, which I already alluded to. This part is fairly simple. Less pressure drop = larger filter area, with any specific filter media. It is true that some filter manufacturer's elements of equivalent sizes have lower pressure drops than others with similar MERV ratings, but it is not enough of a difference to really get one's attention. You also find that once the filters are in use for a short time, that they are about equal. Again, no free lunch. No elfin magic. You want more CFM? Use a larger cartrdge!

Then there is dirt holding capacity. This used to be a big thing that manufacturers pushed. They would say theirs had more dirt holding capacity with less pressure drop. Blah, blah, blah. Well, that kind of caught up to them and was found to be pretty much smoke and mirrors by all the guys that spec'd this stuff in (like me). In the end, it simply comes down to surface area and depth of the media material. The same stuff that causes less pressure drop. So for more dirt holding you need more surface area.

And then of course, there is filter element cost. For the most part, better high MERV number filters with large surface areas means more $$$$, the elements simply cost a lot more to make. Still hard to get around the old "you get what you pay for" adage.

Finally, there is the issue of cleanability. Bag filters can be cleaned, but don't do a good job of filtration. Cartridge filters (With few exceptions) cannot be cleaned. Once plugged, their plugged. Any attempt at cleaning them just results in filtration degredation. Yep, your flow will come back up if you clean them (I'm not talking aout knocking off a cake build up on them, but cleaning the media out itself), but at the cost of destroying the efficiency of the media and not even knowing it! :eek:

Coming back down to the ground and leaving that ideal filter behind that is made of that rarest of materials, unobtainium expensivium, we find in our real hobbist world (many of you are professionals, so the rules are a bit different there), we can live with some exposure to the dust. You have to decide on how much. Understand that it is the really fine stuff you CAN'T see that does you the most harm. You have to go out there and read about the exposure and what you think you can deal with, but even this data is fraught with marketing fear hype, so be careful. Then you have to consider how deep your pockets are, which will probably make you decide to live with a bit more exposure than you wanted to in the first place. Then you decide how much CFM with what level of filtration you can afford to buy. In reality, very few of us can really afford to buy the level of filtration we should have. I think most of us go for higher CFM and sacrifice true filtration quality, simply because so few truly understand it and therefore don't see the value and need for the high dollar filtration systems. I don't own as good as I would like. The best systems from a health and cost standpoint use a good cyclone and push the air back outside drawing fresh air into the shop. High CFM, no filter pressure drop or cost to consider and true fresh air exchange. You can't beat that.

So where does this leave you Eric? Scratching your head, I am sure. You know you need some minimum CFM, which was discussed ad neaseum in previous posts. Lots of data out there to look at. In the end, you will probably start with some minimalist system like all of us and upgrade as money allows. Repeating from the beginning of this post: Some filtration is better than none, provided you have adequate CFM for what you are doing.

Now let the flaming begin! :rolleyes:


What happened to the discussion of the micron filter rating? That's what I'm interested in. If you have a higher HP motor pulling more air but it's only capturing up to 2.5 microns, how do you compare with less CFM but a filter that captures up to 1 micron?

[Eric Schniewind]

Okay, thanks Scott for your very thorough answer. My head is spinning a bit but this is all great stuff. Now I'm just trying to pull out the core concepts here:

1. Micron ratings are misleading. They indicate the ability of the filter to take out some percentage (a majority I hope) of that dust size.
2. Bag Filters vs. Cartridges = oranges vs. apples (but you seem to suggest that both have real downsides. You describe cartridges as better due to having less of a pressure drop but their downside is they cannot be cleaned. I'm assuming once plugged they need to be replaced and who knows how long this might take and how to really know.)
3. You assume correctly in that I'm a hobbyist with a very limited budget. I have been leaning towards the Delta 50-760 1 micron filter bag system. But this discussion has made me wonder if the Grizzly 2 HP would be better though I wondered about the 2.5 micron rating and how to compare with Delta's. From your post it sounds like what I would really need to compare is the beta and MERV ratings from each of these machines which sounds like it might not be readily available.
4. I might be splitting hairs by agonizing over these two machines or any others in this price range. Both are better than none and neither will fully protect me.

If I've oversimplified anything or been inaccurate in any way I'd be keen to hear about it.

Cheers.

[Scott Myers]

Eric,

You're on track.

Point 1 - Don't assume that the micron rating means it will get the majority of that micron particle and larger. That's a bad assumption. Too many variables.
Point 2 - Pretty spot on. In a world where money is no object, the cartridge wins. From a health standpoint, the cartrdige wins. Yes, both have downsides, but the cartrdige has A LOT less downside. Just costs more. However, going to an expensive cartridge without a decent separator or cyclone would cost you a fortune in cartridges.
Point 3 - You can't really compare the bag ratings, as this is some pretty questionable stuff, as I mentioned in my previous post. The MERV number difference are probably nonexistant. Here is a link showing that in the 1-3 micron range, a bag filter removes less than 50% of the particles. This is just one such piece of information out there on how ineffective bag filters are. http://www.strion.com/docs/StrionAir_understanding_filter_ratings.pdf

So calling a bag filter 1 micron or 2.5 micron seems a bit silly. It's just marketing. They are both equally ineffective, when comparing to a good cartridge. But compared to no filter at all, they are great.

Hey, here's a challenge for you. Try calling Grizzy, Jet, Delta, whoever you like, and ask them for their technical data, such as MERV numbers, delta-P, etc, on their bag filters. I tried it with two manufacturers of DC's. The phone will go eerily silent as you can hear the tech pondering the nonsense (in his mind) tht you have just asked. You might as well ask them for winning lottery numbers. I find it a wee bit odd that they can market their bag as a certain micron rating yet somehow have no technical data to back it up. If you do get some supposed technical data, it won't be anything worthwhile that gives you meaningful data. Strange, don't you think? Why would that be, do you suppose? Yeah, you know the answer already.

Not trying to talk you out of either the Jet or Grizzly. By no means. Buy one! Then upgrade as your cash flow allows. You can fit a cartridge on top where the bag would go later on. Just don't forget to fabricate or buy a good separator first which is another subject in itself. (No! Let's not turn this into another separator VS cyclone thread guys.)


Okay, thanks Scott for your very thorough answer. My head is spinning a bit but this is all great stuff. Now I'm just trying to pull out the core concepts here:

1. Micron ratings are misleading. They indicate the ability of the filter to take out some percentage (a majority I hope) of that dust size.
2. Bag Filters vs. Cartridges = oranges vs. apples (but you seem to suggest that both have real downsides. You describe cartridges as better due to having less of a pressure drop but their downside is they cannot be cleaned. I'm assuming once plugged they need to be replaced and who knows how long this might take and how to really know.)
3. You assume correctly in that I'm a hobbyist with a very limited budget. I have been leaning towards the Delta 50-760 1 micron filter bag system. But this discussion has made me wonder if the Grizzly 2 HP would be better though I wondered about the 2.5 micron rating and how to compare with Delta's. From your post it sounds like what I would really need to compare is the beta and MERV ratings from each of these machines which sounds like it might not be readily available.
4. I might be splitting hairs by agonizing over these two machines or any others in this price range. Both are better than none and neither will fully protect me.

If I've oversimplified anything or been inaccurate in any way I'd be keen to hear about it.

Cheers.

[Carl Babel]

Scott,

While I agree with much that you are saying, I disagree with your statement that cartridge filters cannot be cleaned. Rather, I should say that I don't agree with the "scale" implied in your statement.

Filters work by "snaring" dust particles as the dust-laden air passes through the filter. They accomplish this task by having numerous fibers that are smaller than the dust particles that they are capturing. This capture process probably causes some degree of degradation to the filter material. I picture a jagged boulder hitting a dangling rope (seems a reasonable analogy, given that wood has silica in it). But, the more elastic and resilient the fiber material is, the more of this abuse it can take.

The inverse process (cleaning) is accomplished by knocking these particles out of the "clutches" of the filter media, using either vibration or reverse air/water flow. This process also causes filter media degradation. Again, materials science can mitigate this degradation by providing pliant filter fibers.

Ultimately (and in support of your statement - but to a lesser degree), some particles will become so ensnared within the filter fabric that it would take consequentially destructive force to dislodge them. So, the real question (with regards to cleaning) is how many useful cleaning cycles can be run on the differing filter media types? Unfortunately, most manufacturers don't publish this information. There are a lot of variables: wood type (silica content), air speed, release mechanism, to name a few.

[Scott Myers]

Carl,

For the record, this will be my second attempt to answer your points. Not meaning to, my wife closed the window I was typing in the first time when I walked away for a few minutes. :( She isn't the most computer savvy person in the world, but I love her anyway. :)

I have to agree with your statements, to some degree. It seems to make decent common sense on the surface at least. I have to admit to myself that the filter element manufacturing world is in the business of supplying new filter elements, which is where 80% of my training in filters came from in the first place. So how could I find out the real world answers on if a supposed "non-cleanable" element is really celanable or not, and to what degree?

I decided to call a couple of associates I work with all the time. One is an engineer and owner in an industrial cyclonic dust collector manufacturer, who I sell product to. The other is an engineer and salesman in the filter element manufacturing world, who I buy product from. What was intended to be a 5 minute conversation with both, turned into a 30+ conversation with either and then another one of my diatribes here!

When I asked the question of the filter manufacturer, he flat out said up front that they can't be cleaned. So I pressed him, and he conceded that it is done all the time and they even design systems in many applications, including dust collection, to reverse flow the elements to clean them out. But he was quick to point out that this does degrade the element when done, so you have to start with an element that is too big/too fine for the application knowing it will degrade as it is back-flowed and that a replacement period is decided upon after a certain number of back flows, which has to be learned through testing and experience. In other words, he couldn't say how many times it could be cleaned. It is too specific to the application.

The DC manufacturer was a little more forthcoming and "real world". He said that in order to compete, you have to design you system and filters for it so it can be cleaned by back-flow. Everyone in the industry does it, so you have to too if you want to be competitive. It is done automatically on his equipment, as it monitors itself for pressure drop across the filter and when a certain drop is reached, it back-flows. The elements are only replaced after the time between back-flows reaches a certain point (customer decided) that is too short or it quits back-flowing altogether, which tells you the elements are blown open. (Dust coming out is of course another indicator of this.) He did also point out that everyone in the industry knows it degrades the filter each time due to flexing and material impregnation. It depends upon the application whether it is flexing from back-flow or material impregnation will kill the element first. The first will cause it to fail with a higher CFM, but the MERV numbers will go way down. The second will cause it to fail with a lower CFM, but again the MERV numbers are way down.

He also pointed out there is a big difference between back-flowing in his application automatically, which back-flows the entire filter area at about 2-3 times the normal CFM VS hitting the element with high pressure shop air in concentrated points and moving the air hose. He said that hitting it in this manner causes major flex at the point of air contact and rapid degredation, if not instant. (Depends upon the kind of media used to make the element.) He did say that sometimes due to problems in the the field, that they are forced to do this also. He recommends that his customers get no closer than 18" with an air hose to keep the media as intact as possible. He said he has played with this in the shop and knows it does cause a more rapid breakdown.

They did both say that under no circumstances should an fine micron / high MERV element designed for use in dust collection be cleaned with a liquid. They also pointed out that not all media materials are cleanable. Some break down immediately when back-flowed.

So apparently, a "non-cleanable" element can indeed be cleaned, at least to some degree if care is taken. But not indefinitely. So armed with this info, I would probably clean my own with an air hose too, but very carefully.

A couple of other interesting sidebars came up in the conversations that seemed pertinent.

The DC manufacturer explained some "difficulties" that come up often that is filter element related. After they sell their cyclonic collectors, they will get calls from some customers with various failures who are demanding warranty calls. The failures include motor burn-out, imploded elements, too low CFM with constant reverse flow cycling, and a number of other problems. So they fly a guy out and find out that that they have replaced the original elements with an aftermarket "will-fit" element. This happens because they will quote the customer replacement elements and they get sticker shock, so they go looking for an element and find one that is the same size, has the same CFM rating and the same micron rating. (They even have big warnings all over the manuals about using any aftermarket elements.) And no surpirse, problems occur. Of course, the customer denies this fact over the phone (often times what management/maintenance knows and what purchasing does are two different things). Of course this is a VERY expensive lesson for the customer, as they have to eat the travel expenses, service time plus repair the DC and buy the original OEM filters anyway! Ouch. The point that I find pertinent is that even though filter elements may look to have the same rating on the box, you better REALLY know where they came from, who made them and will they really perform as advertised/expected. More often than not, low price means low performance or low quality. Again, Mr. "you get what you pay for" rears its head.

The exciting thing that I learned is my buddy in the DC business apparently has made small "consumer grade" DC's in years past, which I was not aware of. He defines small as less than 10 HP. I supply him motors to drive the impellers on his typical 20-30 HP applications, with some larger. Because I asked these questions, he brought me up to speed in that he is looking to perhaps launch a new smaller cyclonic DC for applications such as woodworking. We discussed the market to a great degree. So I am now hoping I can get one of his prototypes for low cost, if any. All I have to do is supply test data. Since I don't have a cyclone currently, I am certainly all for that! :D


Scott,

While I agree with much that you are saying, I disagree with your statement that cartridge filters cannot be cleaned. Rather, I should say that I don't agree with the "scale" implied in your statement.

Filters work by "snaring" dust particles as the dust-laden air passes through the filter. They accomplish this task by having numerous fibers that are smaller than the dust particles that they are capturing. This capture process probably causes some degree of degradation to the filter material. I picture a jagged boulder hitting a dangling rope (seems a reasonable analogy, given that wood has silica in it). But, the more elastic and resilient the fiber material is, the more of this abuse it can take.

The inverse process (cleaning) is accomplished by knocking these particles out of the "clutches" of the filter media, using either vibration or reverse air/water flow. This process also causes filter media degradation. Again, materials science can mitigate this degradation by providing pliant filter fibers.

Ultimately (and in support of your statement - but to a lesser degree), some particles will become so ensnared within the filter fabric that it would take consequentially destructive force to dislodge them. So, the real question (with regards to cleaning) is how many useful cleaning cycles can be run on the differing filter media types? Unfortunately, most manufacturers don't publish this information. There are a lot of variables: wood type (silica content), air speed, release mechanism, to name a few.

[whit richardson]

If there is a catagory for this I smell a Nobel prize in DC research coming somebody's way soon. I've sent this thread to Stockholm for review. :D

(Grizzly 2hp goes on order this weekend, w/ remote.)

[Carl Babel]

Scott,

Good stuff! It is great to get the technical info from yourself and your contacts in the industry (I have been going largely on common sense). It sounds like we are down to this:
- First, the obvious: the better separation you get in your first stage, the longer your filter will last.
- The filter will degrade from collection alone, but the amount is hard to predict.
- Cleaning will degrade the filter, but the amount is hard to predict.
- The cumulative effect of filter degradation is either:
--- CFM reduction. Caused by impregnation. Not desirable, but not horrible.
--- MERV reduction. Caused by filter material breakdown. Could be insidious if undiagnosed.

Given the information that you have provided, I think I will do the following:
- Look for a good price on a Dylos particle counter and use it regularly.
- Clean the filters "gently":
--- I have been using compressed air; I'll take your friends advice and try the 18" rule.
--- I never did like flappers; maybe I'll look into a brush (like Griz).
--- One guy suggested using an old palm sander and letting the vibration knock stuff loose. Might be worth a try.
- Try to monitor CFM. I'll probably start low tech, maybe tie some ribbons onto the outside of the filter.

It would be great if one of the magazines would do an elaborate study on cyclone separation efficiency (even better if they measured it at different particle sizes) and filter "cleanability". Anyone know any of the editors?



BTW, Whit, I apologize if you feel like we have high-jacked your thread.

[whit richardson]

I've decided to basically hold my breath during all sawdust producing operations in the shop, finish carefully then run into the kitchen and exhale. Get a cup of coffee and head back to the shop. :D

[Scott Myers]

ROFL Whit. Now that is TRUE low tech!

It sounds you have it about right Carl.

[JohnMorgan of Lititz]

Wow, this really turned into quite the dust collector thread. Fine Woodworking did a fairly indepth review of a bunch of the standard 1.5HP collectors. While all had the appearance of being created equal, there were remarkable differences in performance and a key element to all of this: Static pressure.

The Griz 1028Z, Jet DC1100, and little Delta 50-760 all tied for best overall.

I ended up w/ the Jet1100 and am pleased. My table saw still spews forth from the blade up into the air, but i suppose little can be done to remedy that.

I took good advice from the Woodcraft sales guy - do NOT buy the Jet w/ built-in remote control. He told me they were notorious for going bad. I bought the simple 30 dollar plug in model from woodcraft and it works perfect.

Just my simple .02. :)

[Rod Sheridan]

I ended up w/ the Jet1100 and am pleased. My table saw still spews forth from the blade up into the air, but i suppose little can be done to remedy that.

. :)


Actually John, a lot can be done about the dust ejected from the top of the blade.

Many on this forum have an overarm gurad, I have an Excalibur mounted on a General 650.

The overarm removes almost all the dust from the top of the blade.

regards, Rod.

[whit richardson]

ROFL Whit. Now that is TRUE low tech!

It sounds you have it about right Carl.

While I am known to be somewhat of a smart:eek: at times the discussion is helpful. BTW I just got a shipping notice.. it seems Santa actually drives a semi for Yellow Co. and my Grizzly 2hp canister DC is in the sleigh.. Ho..ho..ho..

Keep tuned for my next thread question... What is the best Ambient airfilter system? JDS, Jet, Griz...? (I can only imagine the responses...)

[JohnMorgan of Lititz]

Actually John, a lot can be done about the dust ejected from the top of the blade.

Many on this forum have an overarm gurad, I have an Excalibur mounted on a General 650.

The overarm removes almost all the dust from the top of the blade.

regards, Rod.

Good to know. Thanks! Does that do all the dust collection for the tablesaw or do you tag team it with the cabinet collector and the overam collector? I'm guessing you use both...

[Joel Earl]

Keep tuned for my next thread question... What is the best Ambient airfilter system? JDS, Jet, Griz...? (I can only imagine the responses...)

me too. I guess....or not. I can see it now:rolleyes:

congrat on the score btw - have fun with it

[steve huff]

If you have found a dw735 for 499 you better buy It I think the regular price is 649. I have one and am very happy with it. just wear you ear plugs
steve

[Sonny Edmonds]

I am buying a DC system this week. I have been reading all the posts on this forum, now I am more confused than when I started. I have learned
that sawdudt is far more dangerous than neuclear fallout. How I have survived breathing the stuff for 64 years is only by the grace of God. Bag collectors vs cyclones. What is the truth and what will work efficiently without breaking the bank? I had my mind made up to buy the Griz 0458 3 hp. which is $395. now I read here that the 2 hp. 0548 @ $425 works great. what is the difference? I would expect to pay more for the 3 hp.
I have a 35' x50' shop with TS,BS,belt sander jointer drill press 12" bellsaw 5hp planer, 13' Ridgid plNER 10' slide miter saw and a 10' RAS. I plan to vent outside. any suggestions and advice would be appreciated. Further confusion will also be accepted.

If you can just blow it outside, just get a blower and set up your shop with it as central to your areas of use as you can.
Then let it pump everything outside. No bags, no chambers, no problem! ;)
Well, almost no problem. Anything passing through will get wanged around in the blower a bit before passing. :eek:
In that respect, a cheap Japanese or Chinese blower would be the best cornsideration. The steel wheels are riveted together, and not apt to erode or break like the cast aluminum ones can. :)

[JohnMorgan of Lititz]

You went with the Grizzly 2HP ?? They suck....

:)

congrats on the score!



While I am known to be somewhat of a smart:eek: at times the discussion is helpful. BTW I just got a shipping notice.. it seems Santa actually drives a semi for Yellow Co. and my Grizzly 2hp canister DC is in the sleigh.. Ho..ho..ho..

Keep tuned for my next thread question... What is the best Ambient airfilter system? JDS, Jet, Griz...? (I can only imagine the responses...)

[whit richardson]

To wrap up ... the Grizzly 2HP DC is now assembled but not wired yet. Plus I did get the DW735 for 499 All I need now is another 220V outlet and some ducting, flexhose, adapters and a few blast gates. I also got the remote for the DC too.

next up is the air filter thread....

[Lee Koepke]

To wrap up ... the Grizzly 2HP DC is now assembled but not wired yet. Plus I did get the DW735 for 499 All I need now is another 220V outlet and some ducting, flexhose, adapters and a few blast gates. I also got the remote for the DC too.

next up is the air filter thread....

i am going to build a home-made one with a squirrel cage blower and a series of furnace filters. Curious to see how that thread pans out, this one sure generated alot of food for thought :cool: