Rules of Dust Collecting

[Steven Alford]

As stated in a previous post, I ended up with a new (used) dust collector because mine "bit the dust" (hehe).

I got a Jet DC-650. I realize it is probably only good for one machine, but what are the engineering possibilities of reducing the hose down to 2"?? Will this increase my air flow and allow for use on two machines, or is this a pipe dream??
My thought is that we are dealing mostly with fine dust, so there will not be chunks and chips of wood.

[fwharris]

As stated in a previous post, I ended up with a new (used) dust collector because mine "bit the dust" (hehe).

I got a Jet DC-650. I realize it is probably only good for one machine, but what are the engineering possibilities of reducing the hose down to 2"?? Will this increase my air flow and allow for use on two machines, or is this a pipe dream??
My thought is that we are dealing mostly with fine dust, so there will not be chunks and chips of wood.

Steve,

I think the answer to your question is, no. I found with my old version top mount (shop vac floor nozzle (sound familiar?) that my DC acted like it was starving for air.

I used a 4" to 2" reducer with about 4 foot of 2" hose to the nozzle and found that the amount of air movement at the nozzle was not adequate for picking up the dust.

I recall someone posting some good technical info in the dust collection thread about this.

[AskBud]

Half hour video on DC Air-Flow
http://www.shopsmithacademy.com/SS_Archives/SS109/SS109_Dust_Collection.htm
DC Chart
http://www.woodcraft.com/Articles/Articles.aspx?articleid=657
AskBud

[Steven Alford]

Wow!
According to the math this man gives in the video, a 650 CFM machine will produce 13,374 FPM (feet per minute) which is enough to run three machines. One machine needs 4,000 FPM. I find that hard to believe. That is using a 3" pipe.

[lawrence]

I'm certainly no expert, but here's my .02

You want to keep your pipes as large as the input on your collector for as far as you can... don't constrict things at all as you are not trying to increase velocity (as you are probably thinking with the decreased dimension) but are trying to maintain as high a volume as possible... The basic rule here is keep your line to your machine as

1. Short as possible... I keep my lines for my 1100cfm machine around 10 feet and that works fine--it is usually the safest bet with the smaller dc's to take your dc to the tool.
2. as wide as the entry point on the machine.. if that is 4 inches use 4 inch line, if it is 5 or 6, try to use that width and only constrict at the last minute. I'm guessing your input will be 4 inches.
3. As smooth as possible-- flexible hose (with one or two expensive exceptions) has ridges on the inside-- this creates friction which decreases dust flow... I myself use flexible hose but will eventually switch to smooth. If your dc is going to be permenantly mounted you may want to consider going with a ridgid pipe system. (just remember to ground it)

If you have to use turns, use as gentle a turn as is possible... 2 gentle turns are better than one 90. It's amazing how much a tight bend will restrict dust flow.

Also, I highly recommend that for a 650 cfm machine you limit yourself to one line (or multiple lines with gates) I use gates and place them as close to the dust collector as possible while still being functional.

As for narrowing down to a 2 inch hose... this will restrict flow as has already been stated. I know it sounds counter-intuitive, but you want to keep your volume high with a single wide input.

Good luck and I hope this helps,
Lawrence

[fwharris]

Lawrence,

Great information and well worth the .02.

[sk8nmike]

Here's another 1/2 cent on the issue of grounding. If you are just building a DC system or yours is easy to disassemble run a bare copper wire from the blower case down the inside of each tube. If that's not possible wrap the wire around each tube with no more than 1 foot per turn as you go. This will cut down on the static build up on the tubes preventing clogs and nasty jolt

[HighTechOkie]

Wow!
According to the math this man gives in the video, a 650 CFM machine will produce 13,374 FPM (feet per minute) which is enough to run three machines. One machine needs 4,000 FPM. I find that hard to believe. That is using a 3" pipe.

The Jet DC650 is rated 650CFM @ 4". If you decrease the pipe diameter, CFM will decrease also. Running the numbers for 4" gives you ~7500FPM. After figuring static pressure drop from your ducting, it basically is enough for 1 high chip producing machine like a planer or drum sander, or two smaller machines like a band saw and table saw or CW in our case.

There are two things to look at when looking at vacuum, pressure and flow. Small shop-vac type machines use high pressure/low volume, while a dust collector is high volume/low pressure.

Rob

[Steven Alford]

Thanks guys, very good info.
I am going to stick with the 4" and run it through a hole in the garage wall into the work shed on the other side of the wall. I need to put it at about 7 feet up, over the rafters of the shed and down to the CW. That way the ducting is somewhat permanent and out of the way so I can move around in the shop. I am thinking that the total length of ducting should be around 14 feet. Is that too much??

I will have to rebuild the downdraft setup so that instead of the duct going to the underside of the CW (too many bends in the duct) I will have to build a box under the CW (5" high) that has a 4" connector on the side.

I ordered the front dust collector from Floyd so there will be a "Y" connection to that.

Getting a hole in the garage wall is my biggest challenge.

[Steven Alford]

Here's another 1/2 cent on the issue of grounding. If you are just building a DC system or yours is easy to disassemble run a bare copper wire from the blower case down the inside of each tube. If that's not possible wrap the wire around each tube with no more than 1 foot per turn as you go. This will cut down on the static build up on the tubes preventing clogs and nasty jolt

When you run the wire inside the ducting, do you just connect the wire to the metal of the dust collecting machine or do you actually have to have a grounding rod of some sort?? And at the other end (the PVC connected to the CW) what do you connect the wire to? Or can it just be attached to the PVC pipe??

[sk8nmike]

When you run the wire inside the ducting, do you just connect the wire to the metal of the dust collecting machine or do you actually have to have a grounding rod of some sort?? And at the other end (the PVC connected to the CW) what do you connect the wire to? Or can it just be attached to the PVC pipe??


You will want it grounded at both ends (one end work, but both is better). I ground to the metal case on my blower, then to an earth ground I have runnning through out my shop. You can use the case ground of the machine you are using or the ground from any power outlet. The main idea here is to provide a path to ground for any static buildup you get from air flowing through PVC or any other non-conductive pipe your are using. Now if you want you can use metal ducting like professional shops do, me I'm cheap and use PVC.

[chebytrk]

Ok... looking around for a Dust Collector and don't really know that much about them. Lowes has one for $299, 1 micron and 1 HP. Is that good? Sears has some craftsman DCs but they're a little more expensive. Any recommendations on what price range, HP and Micron to look for? Hey, I'm getting one this weekend (one way or another). Floyd, I'll be ordering your top end loader as soon as I get me the DC.
I was also wondering..... it seems that while I was carving on some 1" cedar that I bought, it seems like I had ALOT more fine dust than I usually have with pine and oak that I usually buy at HD. Is that possible? Excuse my ignorance, but I just don't know a whole lot about wood and even less about wood crafting! ha

[fwharris]

Ok... looking around for a Dust Collector and don't really know that much about them. Lowes has one for $299, 1 micron and 1 HP. Is that good? Sears has some craftsman DCs but they're a little more expensive. Any recommendations on what price range, HP and Micron to look for? Hey, I'm getting one this weekend (one way or another). Floyd, I'll be ordering your top end loader as soon as I get me the DC.
I was also wondering..... it seems that while I was carving on some 1" cedar that I bought, it seems like I had ALOT more fine dust than I usually have with pine and oak that I usually buy at HD. Is that possible? Excuse my ignorance, but I just don't know a whole lot about wood and even less about wood crafting! ha

Jerry,

You want the smallest micron filter you can get. Smaller means it traps more of the fine dust inside the bag and does not release it back into your shop and your lungs..

The Lowe's 1 HP for $299 sounds about normal. I bet it is made by Delta. What was the CFM rating on it? Mine is 650 CFM @ 1 HP..some 1 HP units do have a little higher CFM rating..

If they have a floor model you might ask for the manager of the tool section and see about talking them down a bit for floor model. It never hurts to ask!!

Cedar will give off a lot of fine dust so do not be alarmed by that..

Well I guess I had better go get a insert made up for you.. Just send me an email when you are ready!! And Thanks!!!

[dbfletcher]

Jerry,

I bought this one a few months ago. So far I'm happy with it. I only use it with the CW's so I didnt need a multiple machine DC system.

http://www.grizzly.com/products/1-HP-Light-Duty-Dust-Collector/G1163

I also got the 1 micron bag to go with it.

I like that it is wall mount or can be rolled around on the floor. I know there are other manufacutures that also make similar units.

Doug Fletcher

[chebytrk]

Jerry,

You want the smallest micron filter you can get. Smaller means it traps more of the fine dust inside the bag and does not release it back into your shop and your lungs..

The Lowe's 1 HP for $299 sounds about normal. I bet it is made by Delta. What was the CFM rating on it? Mine is 650 CFM @ 1 HP..some 1 HP units do have a little higher CFM rating..

If they have a floor model you might ask for the manager of the tool section and see about talking them down a bit for floor model. It never hurts to ask!!

Cedar will give off a lot of fine dust so do not be alarmed by that..

Well I guess I had better go get a insert made up for you.. Just send me an email when you are ready!! And Thanks!!!

Thanks for the info. Seems like although Lowes has them, there aren't any at any of the stores that I've checking around the Dallas area. I hate to have to order one so I'm gonna keep looking around. I may go and check Sears and see about the craftsman that I see on the internet. I'll see if they have one available. For sure I'll be ordering your insert and l'll contact you as soon as I locate a DC. I've got Paypal already all set up so all that should be OK as far as placing an order thru you. Thanks again.

[chebytrk]

Jerry,

I bought this one a few months ago. So far I'm happy with it. I only use it with the CW's so I didnt need a multiple machine DC system.

http://www.grizzly.com/products/1-HP-Light-Duty-Dust-Collector/G1163

I also got the 1 micron bag to go with it.

I like that it is wall mount or can be rolled around on the floor. I know there are other manufacutures that also make similar units.

Doug Fletcher

Hey Doug,

So what did it take, about 7 days to get it? It looks pretty good. I like that it's small and all I'll use it for is the CW. I've got one of the small (barn looking sheds 12x20) from HD that I'm trying to fix up for my wood working area. If I can't find anything locally I may just order that one.

[dbfletcher]

Hmm... I'm from Pa and so is grizzly... so it only took 3 days for me.. not sure how many warehouses thay have. I'd say 3-7 days woud be a good guess.

Doug Fletcher

[captainkidd]

Jerry,

I bought this one a few months ago. So far I'm happy with it. I only use it with the CW's so I didnt need a multiple machine DC system.

http://www.grizzly.com/products/1-HP-Light-Duty-Dust-Collector/G1163

I also got the 1 micron bag to go with it.

I like that it is wall mount or can be rolled around on the floor. I know there are other manufacutures that also make similar units.

Doug Fletcher



Doug, I have been considering the very same one. As I mentioned in another thread "eventually" when I get my shop built I will invest in a real nice big cyclone DC system but until then I am also working in a limited space so I don't have the room to get anything real big. With that said, I know you mentioned you are fairly happy with it so I assume it does a pretty decent job with the CW. I think I might setup both a downdraft and the front mounted DC system and I am hoping that this little unit will suffice for that. I have also thought about getting a Oneida Dust Duputy to mount between the CW and the Grizzly to help with separating the dust out of the air to keep the filter bag in the Grizzly from getting full but I don't want to take too much away from the limited CFM that this unit provides. Any thougts to this?

Thank

Brian

[Steven Alford]

You also might want to check out craigslist.com
Someone in your neighborhood may have a dust collector that they are trying to get rid of, cheap.

[chebytrk]

Hmm... I'm from Pa and so is grizzly... so it only took 3 days for me.. not sure how many warehouses thay have. I'd say 3-7 days woud be a good guess.

Doug Fletcher

Just ordered my little Grizzley 1163. Doug, I noticed that it didn't show coming with 4" hoses? Can I just buy that at HD or Lowes? Also noticed in accessories section that only the 3.0 micron bag and another bag that was for the 1163 so I ordered both.