DIY Dust Cyclone - backwards WIP

[Henning]

Very nice, Mark!

And completely blows the one i started yesterday out of the water, which means i wont be adding that here either

Nice work, nonetheless

 

[MikeG.]

This set up obviously works since we can all see the evidence, but surely it must be a bit messy emptying the box ?
How does it handle chips from a PT ?
Mark

Whilst the current set-up isn't too bad when it comes to emptying, because the dust is actually really tightly compressed by the forces in the box, it is easy to imagine how it might be improved. For instance, I could make a removable box to fit within the existing set up........or, starting from scratch I could have two seperate boxes, with the top one doing all the work with the pipes & baffles, and the bottom one just being a bin/ recepticle for the waste.

I haven't linked it up to a P/T , but it would clearly work. It doesn't reduce the suction or flow rate from the original vacuum cleaner/ extractor, so if the base extractor works with a P/T, then so will this set-up.

In fact, I have in mind a test to see whether this machine could convert the high speed extraction from a vacuum cleaner into the high volume extraction required for a p/t, which would then save the bother of having to go and buy a new extractor.


Mike

 

[Krysstel]

How far into the box does the upper baffle go ?

Mark

 

[TrimTheKing]

Advance apologies for being an silly person, but what is a baffle, and what does it do?

Cheers

Mark

 

[Krysstel]

Advance apologies for being an silly person, but what is a baffle, and what does it do?

Cheers

Mark

A deflection plate that, well, deflects. Anything - air, dust, water.
You can see one of them hanging vertically down in the bottom part of Mark Garnham's dust box.

Mark

 

[MikeG.]

Mark(s),

a baffle is just a bit of wood that disturbs the airflow, or causes it to change direction.

The upper baffle is just a loose-fitted piece of wood with dozens of holes (c. 10mm) which goes the full depth of the box.It seems to stop the finer dust from going to the vacuum cleaner. As you can see, it piles up in front of the baffle. There is another baffle with holes at 45 degrees in the corner below the shelf.

Don't get too hung up on this design. My other one is quite different.......the principle is to make the air travel a long and circuitous route through the box, and almost any design doing this will work. I should have patented this 15 years ago when I dreamed it up........I could be retired to my workshop by now on the proceeds!!!!

Mike

 

[TrimTheKing]

Mark(s),

a baffle is just a bit of wood that disturbs the airflow, or causes it to change direction.

The upper baffle is just a loose-fitted piece of wood with dozens of holes (c. 10mm) which goes the full depth of the box.It seems to stop the finer dust from going to the vacuum cleaner. As you can see, it piles up in front of the baffle. There is another baffle with holes at 45 degrees in the corner below the shelf.

Don't get too hung up on this design. My other one is quite different.......the principle is to make the air travel a long and circuitous route through the box, and almost any design doing this will work. I should have patented this 15 years ago when I dreamed it up........I could be retired to my workshop by now on the proceeds!!!!

Mike

Thanks Mike.

another question then, I have read much about making sure as to not have too many bends in the 100mm pipes feeding my extractor to ensure you get the full amount of suckage.

Does this kind of design (or any similar ones) not cause this same problem, or is the impact negligible?

 

[MikeG.]

Mark,

This box has an immeasurably small impact on the suction. If you take the hose direct from the vacuum cleaner, it will hold up a piece of ply of size X. Then re-connect the cleaner to the box, and using the hose from the box, it will hold the same piece of ply. I loaded it all up and tested it to its limits when I first made the thing, and I couldn't measure any difference between the two.

A member here, Derek Willis (I haven't seen anything from him in a while???), saw this design and made one of his own last year. He now swears by it. The thing is, it is so simple that you can make one in an hour out of scrap. That isn't a big risk!!

Mike

 

[TrimTheKing]

Mark,

This box has an immeasurably small impact on the suction. If you take the hose direct from the vacuum cleaner, it will hold up a piece of ply of size X. Then re-connect the cleaner to the box, and using the hose from the box, it will hold the same piece of ply. I loaded it all up and tested it to its limits when I first made the thing, and I couldn't measure any difference between the two.

A member here, Derek Willis (I haven't seen anything from him in a while???), saw this design and made one of his own last year. He now swears by it. The thing is, it is so simple that you can make one in an hour out of scrap. That isn't a big risk!!

Mike

Absolutely, looks good to me, I might have to give it a crack when I am off next week.

Cheers

 

[wizer]

I changed Henry's bag today... 3 weeks since it's last change! I'm looking into this one.

 

[Dave S]

Purely out of idle curiosity, how much does a traffic cone cost and where do you buy them?

Do you have any students near you???

cheers
Dave

 

[Dave S]

I just use one of these On a dustbin works a treat I haven't emptied the bag on the chip collector in six months

http://www.camvac.co.uk/images/accessor ... 50-118.jpg

You know, I never realised until now that Camvac are just a few miles from me.

If ever a company needed a new website, though - looks like it pre-dates the camvac by about 10 years!! :lol:

cheers
Dave

 

[Dave S]

I promised pictures........

Obviously top......closed, bottom........open for dust removal.

This is the small one for my bench, but I have another over the other side of the workshop for some of the other tools which is a different shape but exactly the same principle. There is absolutely no need whatsoever for a cone or cyclone-effect .......simply create a long path for the air to get through a box, and it will drop its dust load.

One day I will make a room-sized version hooked up to a network of rainwater downpipes to all the machines.

Mike

What your design and those found here and here demonstrate quite clearly is that a simple approach can, in practical terms, give almost as much performance as the most highly designed solutions. The law of diminishing returns is quite graphically demonstrated.

I think much of the effect of your design, Mike, is down to the massive change in cross-section as you go from pipe to box. Guessing the dimensions, the box probably has an area 200x that of the pipe - hence the mean velocity of the air in the box will be 1/200 that of the air on the pipe. It is the velocity of the air which keeps the fine dust in suspension.

The baffles look to be setting up turbulent eddies, which is why there is a pile of dust in the middle of the box, just after the baffle. Overall, the restriction to flow caused by the baffles is fairly low, which is why in practical terms you notice no 'loss of suck'.

I made something even simpler some years ago with only 1 baffle. It wasn't as effective as yours (some fine dust did get through to the vac) but the filter bags on the vac required changing far less frequently.

I wouldn't be very optimistic about moving large amounts of chips with a vac, but for the time and cost involved it's got to be worth experimenting.

cheers
Dave

 

[frugal]

I changed Henry's bag today... 3 weeks since it's last change! I'm looking into this one.

You use the bag? I must confess that I never both with the bag. The white mesh filter is good enough to stop pretty much everything that the paper bags ever did. The body will contain twice as much stuff as the bag did and in order to empty it, I just take off the hose and the lid and then upend the body onto the compost heap.

Although looking at a couple of those links, a dustbin cyclone may be on the cards.

 

[woodbloke]

Mike - a request. Could we have a couple more pics please of the internal gubbins?..holes etc. All is not too clear from your current pics - Rob

 

[9fingers]

Purely out of idle curiosity, how much does a traffic cone cost and where do you buy them?

Between £5 & £13 each according to size

http://cpc.farnell.com/jsp/level5/modul ... 406955.xml

carriage free on orders over £45 ish. Loads of goodies - challenge you to spend less than £50!

Bob

 

[MikeG.]

Mike - a request. Could we have a couple more pics please of the internal gubbins?..holes etc. All is not too clear from your current pics - Rob

Yep, sure thing Rob...........I'll sort that now. As it happens, I gave it a good clean out yesterday, so everything should be quite clear.

Do read Dave S's post, though. He re-iterates what I said previously.......the internal design isn't actually that important.

Piccies soon......

Mike

 

[MikeG.]

Right Rob,

pictures as promised......

Firstly, the door is held in place by something as sophisticated as a dowel in a hole:

This is the upper baffle, removed. It only sits in place loosely, and just gets shoved back any old where after a clean:

The hole in the middle shelf:

The corner baffle, a bit of hardboard with a few holes, bent into place between two battens:

An over-view (note the pencil it sucked up earlier today), You can see that the dust gets finer and finer the further it goes through the system, and virtually nothing gets into the final chamber:

A view of the inlet and first baffle. You can see the construction is all just crappy contiboard. It was built as an experiment, but worked so well without any tweeks that I haven't touched it in 15 years:

Just about the only important part of the design. This is the seal that goes around the door. Any draught strip from a DIY shop will do just fine, but it does have to be continuous. The door does not have to be held tight shut, because the vacuum pulls it tight against the seal.

As I said, don't take too much notice of the design. The principle is so simple, just adapt it to suit the space.

As you can see, I have been doing some woodwork after about 6 months of playing with aluminium and fibreglass. I'll do a posting in the next few days......but boy, does it feel nice to be playing with wood again, even just a bit of old pine!

Mike

 

[woodbloke]

Mike - many thanks...I've saved this thread onto 'Favouites' and will come back to it later on...may well have a go at building one and see if it will suck chippings from the p/t as well (using the Camvac 386 as a sucky source) - Rob

 

[wizer]

Thanks for the pics Mike, it's still not fully clear to me. Where are the inlet and outlets?