Thread: How can I improve this DE?

The same old problems are appearing over and over again on this forum.

Your two main problems are VERY common.
1) You absolutely have to get that DC outside the shed, or enclose it in an air tight chamber and vent the chamber outside.
All DCs leak and the older they are the more they leak.
Any enclosed chamber has to be truly airtight otherwise dust will leak back into the shed.
And don't forget the vent from the chamber to the outside needs to be significantly larger than the ducting size use on the input to the machine.

2) Provided the DC is up to utilizing 6" ducting (see below) the next major problem is the use of 4" ducting. 4" ducting will barely do a fair job on a 4" let alone a 400 mm thicknesser. 6" ducting all the way including opening up the machine ports to make use of 6" ducting. But you can't just hook up 6" ducting and expect it it work efficiently unless the DC can use the larger cross sectional area of the bigger ducting.

RE: BAGS
I would always advocate using transparent bottom bags. The DC should be emptied when the bottom bag is no more than 2/3rds full - when the dust level goes above that, the small amount of cyclone action that a DC has is reduced or ceases to work and more dust comes out of the top bag.

RE: DC ITSELF
Before recommending any action I would want to know the structure of the impeller outlet and bag housing in the area marked in the diagram.
If you could take the bags off and take some photos into that area and make some measurements then maybe I could give further advice.
Basically the opening from the impeller to the bag housing MUST be at least equal to the cross sectional area of 6" ducting.
The inlet to the DC on the pedestal also needs to be 6" so the 4" adapters need to be replaced

Although relatively minor the hard right hand angle entry of the air into the bottom of the pedestal and then upwards is far from ideal.
If it were me I would block off the bottom entry and make an oval opening into the side of the pedestal so that an angled port duct could be inserted using a piece of 6" ducting.
For a bit more flow I would replace the top bag with a Pleated filter.
But even after doing all this you won't achieve 1000 cfm with this unit so I wonder, given the size of you combo machine whether it is worth doing
Speaking frankly,you have had 20 years of use out of this DC - I would say it's time to upgrade to at least a 3HP unit but for optimum duct control I would recommend a 4 or 5HP DC with a modern cyclone like a Cleave.

Thanks for the detailed reply Bob. I'll take a few pics of the area in question tomorrow and post them here.

I take your point about upgrading to a bigger & better DE. I'll investigate the cost of a bigger DE and cyclone.

Regards,
Chris

Bob,
Here are the pics of the impeller outlet and bag internal. I hope that's what you were after. These are the best I can do without pulling the motor and impeller off. Let me know if you need me to do that.
Cheers,
Chris

Unfortunately this look very restrictive.

The measurements that matter are those showing in red on this image.



If it was me I would remove the whole rectangular deflector (especially the "fin" in the middle) and then open up the hole in the housing in the are where the red zigzag is.
If you can't get the opening close to the cross section of a 1 150 mm duct then i don't think this DC is worth messing with.

Thanks Bob. I'll investigate the feasibility of what you recommend. So I need at least 176 sq cm?

Is the deflector not necessary for generating a cyclone effect?

Originally Posted by jack620

Thanks Bob. I'll investigate the feasibility of what you recommend. So I need at least 176 sq cm?

Is the deflector not necessary for generating a cyclone effect?

I reckon it would generate turbulence rather than any cyclonic action.
More significantly is that it will restrict air flow.