HF Dust Collector Pipe Size

[David Hostetler]

Here is my thinking Dave; Like I said, the HF has a 5" inlet without modifications. But it also has just a 5" outlet into the filter (I replaces the bag with a Wynn filter). So do you think that upgrading beyond 5" has any real value? I would love to run 6" or even 7", but I'm not sure that it would do much.

What do you think?

That's why I went with 5", was the size between the impeller housing and the inlet ring on the dust collector itself. A lot of folks DO upsize the port on the inlet to 6" but I assume that after the impeller is the restriction back to 5"... So I chose 5" to maximize what I had available to me... And it seems to work well. Now mind you, I am not running 5" to neck down to a 4" port, I am splitting to 2 separate 4" branches, not sure about the whole surface area thing, but it does seem to work well...

[Stew Hagerty]

That's why I went with 5", was the size between the impeller housing and the inlet ring on the dust collector itself. A lot of folks DO upsize the port on the inlet to 6" but I assume that after the impeller is the restriction back to 5"... So I chose 5" to maximize what I had available to me... And it seems to work well. Now mind you, I am not running 5" to neck down to a 4" port, I am splitting to 2 separate 4" branches, not sure about the whole surface area thing, but it does seem to work well...

Thanks Dave, I think I'm going to go ahead with the 5".

[Jason Ryan]

James how did you cut the opening do you have any pictures?

I stumbled across this fantastic free online software by Harder Woods for printing cutting templates to joint two cylinders together. You can choose different size cylinders and add an offset for a side inlet (versus 0" of latteral offset which would join the two in the center).

http://www.harderwoods.com/pipe.html

I threw together a quick template for a 23" barrel and 6" pipe (I guessed .25" thick). To get a full side inlet (they call it ceiling mount in the instructions), you enter the difference of the two radius' in the "latteral offset" box. So in this case I entered 8.5".

http://www.harderwoods.com/pipetempl...&Submit=Submit

I just found it this morning and plan to try it out this weekend.

[David Hostetler]

Sorry about this short derail here....

Then again, an F150 is "better" than my Ford Ranger, and yet I haul lots of stuff just the same

I had to laugh my tail off at that. I presently own an '04 F-150, it replaced a 2000 Ranger. In many ways the Ranger was a better truck. All of it having to do with gas mileage and manuverability. Don't be me wrong, I love my F-150, but with the extended cab, full length box, and much bigger than stock wheels / tires, I REALLY have to think about where exactly I am going to park that behemoth...

Now back to the subject at hand...

The HF 97869 2HP DC can be fitted with a new shop built impeller cover plate (the round thing with the inlet and all the bolt holes) typically guys make them out of 1/2" MDF, but I have seen other materials. The inlet pipe can then be 6" S&D pipe. A far LESS common modification that goes along with that, is modifying the output of the impeller housing to accept 6", and then even rarer, but I have seen one on a forum somewhere, most likely Phil Thien's, is the separator ring inlet tube getting replaced with 6"...

The impeller on my DC is just a hair under 11" diameter, I guess if forced to, it could support 6" duct, but it would never be completely right. Going through my Thien separator with 5", and then out to the ducts through the wye and then to the machiens in 2 4" circuits works exceptionally well for me. Yes I had to run 2 separate duct lines, which adds up cost wise, but I have drops where I need them, and sufficient collection from where I need it from...

[David Kumm]

There are a couple of factors to consider when modifying fan inlets. The fan blades are designed-in theory- to be optimized with the inlet size. Increasing it extends the inlet diameter farther into the actual blade fin and may actually reduce the cfm pushed -pulled by the blades. The surface area of the bag and the type of filter material are often underengineered for the standard collector fittings so increasing them means you probably need to change the bag to an oversized one. The cartridge type are probably OK. If you don't actually increase the cfm moved, the chips start to move too slow in the larger pipe until they restrict the pipe back to something smaller thus increasing the chip speed. Dave

[Lynn Reid]

I have my dust collector in an enclosure on the outside wall of my shop. I have just bought a HF 2hp...I hope it will fit in the enclosure...currently I have a 1HP Grizzly. I was and am seriously disappointed in the 1hp. These mods are interesting. I do think the Y wont fit correctly in my current enclosure...Id much rather have a single out that comes through the wall and then branch from that. I am glad I ran across this thread!
I have read about and watched the Thien baffle videos. I am sort of confused...with all the dust going into the drum/bucket...why even have a dust collector? There must be something I am not thinking of. It looks like a matter of which youd rather empty...the bag or the bucket! Nonetheless...I think I am going to build one.