Thread: The Generic 2HP DC

Thanks for your help Bob. I will get onto this.

Cheers

Originally Posted by BobL

I'm following the number of "views" on this thread and there have been 119 since yesterday - given this number of views I'm surprised there are not more questions.
So to anyone out there just lurking and maybe cautious about asking a question please feel free to ask anything about this.

I am getting there. Bought a table saw last November but have only just got it into workshop, still in the box. Mostly do metalwork and huge amount of arrangements to make on all fronts. Also bought a Milling Machine (not your sort) on same day. I only started looking at DC this morning as I was meant to get one on the day but clean forgot. Good thing. I will finish reading the thread now.

Dean

Ok I have finished reading the thread and had a look at Jonno's as well. I have a limit financially and also to a 2hp unit due to power constraints. I also have limited space and was going to position the DC outside. I still will if it can be done.

Is one of these generic units the best way to go as opposed to say buying bits and making your own in terms of overall performance?

Either way I will be copying the mods in these threads. I will no doubt have more questions later.

Dean

Originally Posted by Oldneweng

.
.
.
Is one of these generic units the best way to go as opposed to say buying bits and making your own in terms of overall performance?

This is another "how long is a piece of string question"

What do you mean by bits and pieces?
If you plan to use a 1HP motor on a 10" impeller and use an old footy sock for a filter then no.
It is unlikely you will be able to buy the components for a 2HP DC much cheaper than a complete unit especially if you get a second hand one.
You need to bear in mind that "any 2HP system" will simply not maintain the generally accepted 1000 cfm @ 4000 fpm anyway.

If you want to build a bits and pieces DC that clearly meets these specs then I would start with a 3 phase 4HP motor with a VSD.
You will need an efficient 15 or 16" impeller - you will be battling to find one of these anywhere.
Then you need either an efficient cyclone of some filter bags and their housing.
AT this stage you may wish you had purchased a Clearvue

Originally Posted by BobL

This is another "how long is a piece of string question"

What do you mean by bits and pieces?
If you plan to use a 1HP motor on a 10" impeller and use an old forty sock for a filter then no.
It is unlikely you will be able to buy the components for a 2HP DC much cheaper than a complete unit especially if you get a second hand one.
You need to bear in mind that "any 2HP system" will simply not maintain the generally accepted 1000 cfm @ 4000 fpm anyway.

If you want to build a bits and pieces DC that clearly meets these specs then I would start with a 3 phase 4HP motor with a VSD.
You will need an efficient 15 or 16" impeller - you will be battling to find one of these anywhere.
Then you need either an efficient cyclone of some filter bags and their housing.
AT this stage you may wish you had purchased a Clearvue

Fair enough Bob. The impeller would be the hard bit to find. I will stick with a bought one. I am a bit iffy about chopping up a brand new one tho.

I don't have the money yet so I will keep looking at different ones and read up on these threads a bit closer.

Dean

Originally Posted by BobL

What do you mean by bits and pieces?
If you plan to use a 1HP motor on a 10" impeller and use an old forty sock for a filter then no.

Actually, I was thinking of trying a USB-powered desk fan and a pair of old jeans with knots tied in the cuffs. Should be a goer i reckon, but you might want to put the jeans outside the shed.

Cheers

Doug

Originally Posted by Oldneweng

Fair enough Bob. The impeller would be the hard bit to find. I will stick with a bought one. I am a bit iffy about chopping up a brand new one tho.

I don't have the money yet so I will keep looking at different ones and read up on these threads a bit closer.

Dean

Maybe you could use a stock one as is for a few months to see if it survives.
In terms of value for money I would buy a used one. The likelihood is the warranty has run out so modding it won't be a problem.

Originally Posted by BobL

Maybe you could use a stock one as is for a few months to see if it survives.
In terms of value for money I would buy a used one. The likelihood is the warranty has run out so modding it won't be a problem.

Survives What LOL? I hadn't even thought of second hand which is unusual for me. I will keep an eye open, maybe both. I would be happier to chop it up then.

Doug

You would have to remember the zip! It would increase the micron size, but if it was outside it wouldn't matter so much.

Dean

Originally Posted by BobL

During last week I made an adapter/flange that looks like this.




and a motor/impeller stand that looks like this




These items, together with the modification to the impeller entrance to accept 6" ducting shown in post # 9 in this thread makes a generic 2HP DC looks like this.



The black metal stand is made of 6 mm thick scrap steel plates, and the upright post is a piece of scrap 50 x 50 x 3 mm SHS, all welded together.
The holes in the base of the stand are drilled such that it uses the existing holes in base of the DC.


The adaptor flange bolts straight onto the existing holes of the impeller outlet and attaches to the bag/filter housing via a 300 mm long arc.
A rectangular hole needs to be cut into the filter/bag housing which take minutes with an angle grinder and a thin kerf cutting wheel.

Is there any particular science in where to locate the hole in the bag housing for the new adaptor flange? And is the size of the hole solely determined by the length of the arc that corresponds to the size of the impeller outlet?

Trav

Originally Posted by Trav

Is there any particular science in where to locate the hole in the bag housing for the new adaptor flange?

Nope. Maybe this is stating the obvious but just in case, the outside wall of the flange connecting the impeller to the bag housing should line up tangentially with the outer wall of the bag housing as per the diagram on the left.
Also I would not reverse the flow direction as per the diagram on the right.

And is the size of the hole solely determined by the length of the arc that corresponds to the size of the impeller outlet? Trav

Yep!

Thanks bob. Just what I thought, but best to check before I begin surgery.

Trav

I am much impressed by Bob's optimisation of a 2 HP dusty. It provides an inexpensive DC solution.

Just wondering ... was wandering around ebay and found 2 HP VFDs for between $90 and $150. I am electrically challenged, so my question is does it seem feasible to get an inexpensive FVD and run the 2 HP motor at 60 Hz?

Originally Posted by John Samuel

I am much impressed by Bob's optimisation of a 2 HP dusty. It provides an inexpensive DC solution.

Just wondering ... was wandering around ebay and found 2 HP VFDs for between $90 and $150. I am electrically challenged, so my question is does it seem feasible to get an inexpensive FVD and run the 2 HP motor at 60 Hz?

The 2HP machines are single phase so a VFD will not work on these.
The motor could be replaced with a used 3 phase 2HP delta wired motor since these are relatively cheap and being only 2HP could possibly be spun a bit faster e.g. 65 Hz but I expect noise will become a problem.

Originally Posted by BobL

The 2HP machines are single phase so a VFD will not work on these.
The motor could be replaced with a used 3 phase 2HP delta wired motor since these are relatively cheap and being only 2HP could possibly be spun a bit faster e.g. 65 Hz but I expect noise will become a problem.

Ah, yes ... noise. I had forgotten about that.

Thanks.