A few questions for the board

[ozhunter]

Hello all

Starting to work up my Dust Extraction set up. I have a DC-7 that I'm stuck with for the moment. I have a couple of questions.

As has been stated many times the design of the DC7 ducting from the impellar to the bags is 50 years old and those that know think it probably isn't very efficient.

What would happen if I attach the impellar/motor to one bag, ala BobL's mods to a 2HP dusty? It looks like the mod would be very easy to do on mine with little or no surgery.

The label says mine is 3HP, 2950rpm. I will confirm the RPM in the next few days.

IF the motor does in fact do 2950, is there any benefit in swapping it out for a 3 Phase and VFD (no 3 phase yet) and spinning it at 60 cycles?

Can someone point me to plans or a thread for making my own blast gates. Plenty of mentions but I can't find any plans. I like the look of the ones BobL has shown, any chance of some pointers Bob.

That'll do for now.

Regards

[mick59wests]

Hi,

a few months ago I visited 'rusel' (his WW id) at Springwood (just a mere toddle down the Great Western Highway for you) to check out his clearvue installation and he had built all of his own blast gates. He was very accommodating so you may want to try and contact him. He had an excellent thread on his install.

cheers

Mick

[BobL]

Hello all
Starting to work up my Dust Extraction set up. I have a DC-7 that I'm stuck with for the moment. I have a couple of questions.
As has been stated many times the design of the DC7 ducting from the impellar to the bags is 50 years old and those that know think it probably isn't very efficient.
What would happen if I attach the impellar/motor to one bag, ala BobL's mods to a 2HP dusty? It looks like the mod would be very easy to do on mine with little or no surgery.

Two bags are less restrictive and also clog up slower than one, so you would still be better off leaving it connected to the two bags.

The label says mine is 3HP, 2950rpm. I will confirm the RPM in the next few days.
IF the motor does in fact do 2950, is there any benefit in swapping it out for a 3 Phase and VFD (no 3 phase yet) and spinning it at 60 cycles?

Yes there is a theoretical 20% increase in flow in going from 50 to 60 Hz
BUT
It will be A LOT NOISER.

[pjt]

AND be consume more power, I did some numbers on how much in a thread only recently.
Rocking%20Blast%20Gate.JPG
This is quite a nice home made gate, not mine, I did make similliar but with a flat slide in/out gate.



Pete

[ozhunter]

That is a nice lookin' gate. I'll put that one in the archive for later digestion.

If I can get a DE system that keeps the nasties out of me. I'll gladly pay $1.60 an hour.

Is there any point in looking at streamlining the ducting between the bags and the impeller. I have access to all sorts of sheet metal and metal working gear and brains.
Would a nice smooth curve down from the bag inlets to the impeller in 6" round sheet steel, made to be symmetrical as can be done and moving the motor/impeller to be exactly between the bag ducts, be theoretically better or worse than the existing duct?

I intend to get a 3PH motor for it, I already have VFD.

Regards

[BobL]

Is there any point in looking at streamlining the ducting between the bags and the impeller. I have access to all sorts of sheet metal and metal working gear and brains.
Would a nice smooth curve down from the bag inlets to the impeller in 6" round sheet steel, made to be symmetrical as can be done and moving the motor/impeller to be exactly between the bag ducts, be theoretically better or worse than the existing duct?

Anything shorter and smoother than the existing arrangement would be better but how much better will be difficult to say and whether it would be worth doing is another question.

Rather than converting the square ducting into round a better design is as shown in the Carbatech CT-003VB DC.
Like my mod to the generic 2HP DC, the impeller is connected direct to the filter housing and the two filter housings directly connected by a very large opening
Carba-Tec Industrial Twin Bag 3hp Dust Collector : CARBA-TEC

in terms of value for time, at this stage I would put more effort into machine port expansions than the impeller/Filter connections