Is it worth it to modify HF Dust Collector?

[drzaius]

It's probably drawing more like 100A initially on start up. 10X FLA is a pretty common starting current. Most meters will not react fast enough to show that though.

[M93A1Prowler]

20 hours ago, wtnhighlander said:

Pulling 18.7 amps briefly at startup will probably not cause a 15 amp breaker to trip, there is a load / time curve they are designed to follow. Repeated stops & starts in a short time might. Make sure the actual wire is good for whatever load you have.

Great info, thanks a lot for that. 

[Minnesota Steve]

I may have to try that impeller.   Thanks for that tip.

So I've modified mine in two ways...

First, got this Powertec 1 micron filter bag.   It's big heavy felt and has worked a lot better than the bag that came with it.

https://www.amazon.com/gp/product/B005VSAP74

Then I just tried this trick from Stumpy Nubs...  Instead of clamps, I drilled some holes into the bottom sides of the bucket and used some bungee cords to hold down the cover.   I have not yet filled it with sawdust yet to see how much of a mess I make emptying the bag.   But it has GOT to be better than trying to put the bag and clamp back on the bottom.

 

[M93A1Prowler]

12 minutes ago, Minnesota Steve said:

I may have to try that impeller.   Thanks for that tip.

So I've modified mine in two ways...

First, got this Powertec 1 micron filter bag.   It's big heavy felt and has worked a lot better than the bag that came with it.

https://www.amazon.com/gp/product/B005VSAP74

Then I just tried this trick from Stumpy Nubs...  Instead of clamps, I drilled some holes into the bottom sides of the bucket and used some bungee cords to hold down the cover.   I have not yet filled it with sawdust yet to see how much of a mess I make emptying the bag.   But it has GOT to be better than trying to put the bag and clamp back on the bottom.

 

Very cool man. I'm lucky enough that when I set mine up, I'm going to vent mine outside. I've read a lot about the air shifts due to the draw and whatnot but winters are never a problem for me, I live in the southwest so I don't need to heat my shop. Cooling, now that's a different story. I tend to work in the evenings moreso than the day in the summers, so I'm good with venting to my side yard. 

[BonPacific]

Venting outside is definitely the best option if you can swing it. I don't have anything to measure CFM, but I'd swear it went up at least 50% when I made the switch.

[wtnhighlander]

I'll say that mine seems to move a lot more air when venting outside, too. Just take care to avoid overfilling the dust bin, or it will vent a big pile of chips in short order. DAMHIK.

[Coop]

By venting to the outside, overall, how much airborne dust, compared to how much lands in a pile, do you get. I understand that the drum sander gives off more “dust” than say the jointer but is it something a city boy and his neighbors can put up with? 

[wtnhighlander]

I'll have to defer to the others on that one, Ken. My sanding devices still connect to a standard shop vac, as the DC doesn't do as well reduced down to a 2" port.

[BonPacific]

@Coop Are you asking about inside the shop or outside? The only tool I have hooked up to the DC while sanding is my lathe, and I'd say just from visuals it picks up about 80 percent of the sanding dust (more for spindles since I can angle it and less for bowls).

For the outside, I vent directly onto a lilac bush, and there's no noticeable pile left over. I have a cyclone through, which does a good job collecting anything large enough to notice. The neighbors (about 20' away) have never mentioned any issues with dust clouds, or noise for that matter.

[Just Bob]

I use a Super dust deputy and vent outside.  I can not see any airborne dust outside, regardless of the tool.  The only downside, for your neighbors,  is that you are also venting a large amount of noise.  I don't have close neighbors, but I was curious and found that I could hear my DC from about a 1/4 mile away.

[Coop]

4 hours ago, BonPacific said:

@Coop Are you asking about inside the shop or outside? The only tool I have hooked up to the DC while sanding is my lathe, and I'd say just from visuals it picks up about 80 percent of the sanding dust (more for spindles since I can angle it and less for bowls).

For the outside, I vent directly onto a lilac bush, and there's no noticeable pile left over. I have a cyclone through, which does a good job collecting anything large enough to notice. The neighbors (about 20' away) have never mentioned any issues with dust clouds, or noise for that matter.

Outside the shop. I have a converted HF system with a cyclone type device that collects the majority of the dust and chips and from there, it goes into a collection bag on bottom and a Wynn filter above it. I think I just answered my own question. Everything caught in the bag and Wynn filter is what will be dumped outside!

[MattCRNA]

Hey guys,

Since the WEN impeller is "new" vs the Rikon impeller that's been popular I thought I would add these pics to the discussion.

One note that I'll add about the WEN impeller. I've seen comments in other forums about the Rikon impeller fitting a little loose. For me the WEN impeller installed easily with several taps using a rubber mallet and there was absolutely no play. It spun up nicely with no hitting, rubbing, vibration, etc..... and appeared to be perfectly balanced by visualization.

I didn't do any air flow tests because I don't have the equipment for that and it seems there's plenty of info out there measuring the differences between the two impellers. But the difference is very noticeable.

Happy New Year!!

Matt

[Tpt life]

Those two impellers are not set up to spin the same way. Any chance your motor was wired to spin backward?

[drzaius]

2 hours ago, Tpt life said:

Those two impellers are not set up to spin the same way. Any chance your motor was wired to spin backward?

The angle & curve of the lower impeller will give high volume, but at lower static pressure. The configuration of the larger one will maintain the volume much better as the static pressure rises. It will handle longer duct runs & a cyclone much better than the stock impeller. I would put an ammeter on that motor though because it will be a lot easier to overload it with the larger impeller. They are not expensive.

[wtnhighlander]

@drzaius comment made me want to learn more about centrifugal fan design. I found this page that has some interesting info, although seems to have been written by a non-native english speaker.

Apparently the choice of blade form has as much to do with the suspended particulates as the air.

[MattCRNA]

12 hours ago, drzaius said:

I would put an ammeter on that motor though because it will be a lot easier to overload it with the larger impeller. They are not expensive.

I have an ammeter, I'll definitely put it in on and see what it reads at start up and steady running.

[Mark J]

And what about the direction of spin on the two impellers being opposite to each other?

[RichardA]

I was curious about that as well.

[drzaius]

2 hours ago, MattCRNA said:

I have an ammeter, I'll definitely put it in on and see what it reads at start up and steady running.

Take readings with various blast gates open and a clean filter to get a baseline idea of how many gates can be open before overloading the motor.

[drzaius]

1 hour ago, Mark J said:

And what about the direction of spin on the two impellers being opposite to each other?

The direction of spin is the same for both impellers. You can't look at an impeller (at least I can't) and determine that it's supposed to spin this way or that, though I'm sure someone who's knowledgeable on impeller design could. Some have the blades inclined in one direction, some in the other. It all depends on the design intent for the blower. My Oneida impeller is similar to the WEN (but cast aluminum, not steel) and spins the same direction.

[Tpt life]

48 minutes ago, drzaius said:

The direction of spin is the same for both impellers. You can't look at an impeller (at least I can't) and determine that it's supposed to spin this way or that, though I'm sure someone who's knowledgeable on impeller design could. Some have the blades inclined in one direction, some in the other. It all depends on the design intent for the blower. My Oneida impeller is similar to the WEN (but cast aluminum, not steel) and spins the same direction.

I can easily see that these are not designed to spin in the same direction. One will direct air to the center and the other to the outside if spun in the same direction. The design of the cage and the direction of airflow through the cage will prefer one over the other. I don’t have that machine’s specs in front of me, but work in this enough to easily spot how they will move air differently. 

[MattCRNA]

I don't know if this helps, but the top dust collector is the brand I have (Harbor Freight) and the lower one is the WEN model (the one with the larger impeller and back leaning blades). 

I've seen both of them operate in person and the impellers spin in the same direction. Other than the color and the difference in impeller design they look exactly the same. The interior of the impeller housing is also exactly the same.

[drzaius]

46 minutes ago, Tpt life said:

I can easily see that these are not designed to spin in the same direction. One will direct air to the center and the other to the outside if spun in the same direction. The design of the cage and the direction of airflow through the cage will prefer one over the other. I don’t have that machine’s specs in front of me, but work in this enough to easily spot how they will move air differently. 

Which way the blades are inclined has nothing to do with the direction of rotation. Looking at the blower housing, it's clear that the original impeller is supposed to rotate clockwise. With the blades at a more radial angle, or even forward of radial, the impeller gives the air more of a 'throw', imparting greater velocity. With increased static pressure, air volume drops dramatically. With the blades inclined backwards, or away from the direction of rotation, the air is not pushed as quickly, but will withstand higher static pressures better. Have a look at a furnace blower. the blades are inclined way forward of radial. It is designed to move lots of air through large ducts. As I said above, the Oneida impellers are inclined in a similar fashion to the WEN impeller.

If I were an engineer, I could do a much better job of explaining, but that's the gist of it.

[Tpt life]

I am not sure I have started this well. If they spin the same direction, they will create the static pressure in two different zones in the cage. Alternate the spin for each, and they will not create the same level of static pressure, but will at least be creating it in the same zone inside the cage. Since flipping the curve makes for better flow, makes me suspect enough to ask the question. Again, the cage is going to function better without cavitation and interruption of flow. Admittedly, my experience is not dust cyclones, but in alarm horns. The principles are common though. 

[drzaius]

@Tpt life, My explanation is not great, and is over simplified, but Google has lots of info. Wikipedia has a decent page on just this subject.