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charlieuk
15-10-2014, 12:29 AM
i am looking idea for a dust extraction system for my cnc that will be cutting large amounts of polystyrene foam. With the foam being so light i huge amounts of power is not needed so would like to try and get a system that is as quiet as posable but suitable to be run for long periods. I have looked at the systems that you can get from machine mart but they are all quite large and noisy so wondering if anyone has any idea for something that maybe a little quieter. One of the other factors is i need it to have a large capacity. would the cyclone things mentioned in the other threads be suitable, i have never seen them before?

many thanks

gavztheouch
25-10-2014, 11:13 AM
I made a giant cyclone for my machine and it worked well when I came to machine some foam. I would say with the sheer volume of dust you are going to produce you will def need a cyclone as a filter based system is going to clog up fast.

Have you seen theses

http://www.ebay.co.uk/itm/Omni-Dust-Cyclone-workshop-vacuum-pre-filter-separation-wood-dust-powder-plastic-/171509292503?pt=LH_DefaultDomain_3&hash=item27eec01dd7

Might be too small for your application? Worth a try

firetrappe
25-10-2014, 01:41 PM
Attached are a few pics of my dust extraction / cyclone system using one of the ebay units : http://www.ebay.co.uk/itm/DUST-MITE-Dust-Cyclone-/321545117510?pt=LH_DefaultDomain_3&hash=item4add951f46

It's mounted to an opaque 25L fermenting bin : http://www.wilko.com/homebrew-accessories+equipment/wilko-fermenting-bin-and-lid-25lt/invt/0022555?VBMST=brewing&VBMST=brewing&VBMTC=979317cbb27336010082a6756d2f3eda

The lid of the bin is reinforced with a disc of MDF which the cyclone bolts to. I also have 3 MDF rings inside the bin to prevent the bin trying to implode! You can see in the photo that I started with one ring in the centre of the bin which wasn't enough (see the stress marks!) 3 rings equally spaced works perfectly.
I could have used a stronger container, but couldn't find anything stronger that was transparent or opaque. I like being able to glance at the bin and see if it needs emptying.

The system is plumbed using standard waste pipe and fittings from B&Q. I also used a couple of these : http://www.axminster.co.uk/numatic-stepped-hose-reducer for connecting the flexible hose to the rigid pipes.

The fitting on the end of the Henry hose is a really nice push fit into the waste pipe. I have a short piece of pipe mounted parallel to the spindle which this pushes into to connect to the dust shoe. If I just want to use the vacuum then I can pull the hose out of the pipe use it manually, I also attach the standard Henry accessories for general cleaning the work area and floor.

I've been using this system now for 4 months and although i've emptied the bin 3 times Henry is completely empty apart from a few specks of dust inside.

So far the dust shoe and extraction has worked really well when cutting MDF, Fibreglass, Cast Acrylic and Foam. The only material it has struggled with is Plywood, this is due to the small diameter of the hose getting clogged with the long spirals of waste material.

My brother asked me if i'd cut a plywood sign for him a few weeks ago (i'd never cut plywood before). I said i'd give it a go and film it for him as he hadn't seen the machine working before. I wasn't going to make the video public as there are some mistakes and it's a bit boring, but as it's relative to what i've written above then here's the link : http://www.youtube.com/watch?v=20atRRHclbM

I regularly run Henry for 2 hours at a time. It pushes out some heat (keeps the shed nice and warm :) ) and isn't going to last as long as a proper dust extractor. It is quieter than an extractor though and is holding up nicely for the type of jobs I do.

Si

Clive S
25-10-2014, 02:53 PM
That looks like a nice machine have you built it yourself? ..Clive

firetrappe
25-10-2014, 03:26 PM
Thanks Clive. Unfortunately I can't take the credit for the machine, it's a 'Dean Special'. I did the electronics and Dean built the machine to the specs I requested. I'd built a wooden CNC machine years ago and knew my limits :stupid:

charlieuk
25-10-2014, 07:58 PM
many thanks for that the dust mite was what i was looking at using, how did it perform with foam? i was worried very light foam may stay airborne and just run all the way to the vacuum? do you think the cyclone drops the power of the vacuum? is your henry have the high and low settings?

best regards charlie

EddyCurrent
25-10-2014, 08:21 PM
I'm thinking you might need a bin with a large capacity, I imagine there will be quite a lot of foam to remove.

JAZZCNC
25-10-2014, 09:05 PM
That looks like a nice machine have you built it yourself? ..Clive

You Old Bugger.!!. . .Lmao

EddyCurrent
25-10-2014, 09:16 PM
That looks like a nice machine have you built it yourself? ..Clive

You Old Bugger.!!. . .Lmao

I knew it was a Hylda Baker moment myself, "(She) He knows y'know"

Clive S
25-10-2014, 09:18 PM
:encouragement:

firetrappe
25-10-2014, 10:33 PM
many thanks for that the dust mite was what i was looking at using, how did it perform with foam? i was worried very light foam may stay airborne and just run all the way to the vacuum? do you think the cyclone drops the power of the vacuum? is your henry have the high and low settings?

best regards charlie

Charlie, It performed well with the foam, I didn't find any traces in Henry anyway. My first machine was used 90% for cutting foam sheets (EPP and Styrene) over a 5 year period, I know how messy it can be! I would think it would work well for your purpose provided you can keep the vacuum inlet fairly close to your foam.

The cyclone has no noticeable difference on the power of the vacuum. I've got one of the newer Henry's with the Hi-Low setting switch and rarely switch it to full power. I imagine on your machine you're going to have quite a distance of plumbing between the inlet/dustshoe and the cyclone. I'm not sure if this distance has an effect on the suction. I do know that smooth walled pipe will give you better flow than ribbed hoses.

You may want to consider earthing the plumbing too. Mine creates quite a bit of static and makes my hair stand on end if I lean over the bed on my machine lol.


Dean, I wasn't sure whether Clive was setting me or you up, or whether he was having a 'senior moment' :p It's probably just payback as you were a day late getting to his place cos of me lol.

JAZZCNC
25-10-2014, 11:10 PM
Dean, I wasn't sure whether Clive was setting me or you up, or whether he was having a 'senior moment' :p It's probably just payback as you were a day late getting to his place cos of me lol.

Nah's he's a Star Man is our Clive and sharp as razor blade even thou he's older than Yoda. It's those Sangria's bringing out is wicked sense of humour. . .Lol

charlieuk
26-10-2014, 05:54 AM
Charlie, It performed well with the foam, I didn't find any traces in Henry anyway. My first machine was used 90% for cutting foam sheets (EPP and Styrene) over a 5 year period, I know how messy it can be! I would think it would work well for your purpose provided you can keep the vacuum inlet fairly close to your foam.


The cyclone has no noticeable difference on the power of the vacuum. I've got one of the newer Henry's with the Hi-Low setting switch and rarely switch it to full power. I imagine on your machine you're going to have quite a distance of plumbing between the inlet/dustshoe and the cyclone. I'm not sure if this distance has an effect on the suction. I do know that smooth walled pipe will give you better flow than ribbed hoses.


You may want to consider earthing the plumbing too. Mine creates quite a bit of static and makes my hair stand on end if I lean over the bed on my machine lol.




Dean, I wasn't sure whether Clive was setting me or you up, or whether he was having a 'senior moment' :p It's probably just payback as you were a day late getting to his place cos of me lol.

Cheers many thanks that's a great help I have run a tube siystem when I shaped by hand so the distance seams fine I will probably get a cyclone and put it on a large blue chemical barel as they are vey strong however I do also have a idea to have a smaller barel with a trap door underneath that allows emptying into a large sack nice and easy.


I cant have the vacuum to close as the bits are quite long and they have to cut quite deep. I'm wondering if I can make something that makes a bit of a cyclone erect comeing out of the dust shoe to help get the foam up from further away perhaps.

Clive S
26-10-2014, 12:23 PM
Charlie I know nothing about vacuum systems but this is a good read. http://billpentz.com/woodworking/cyclone/ also there is a spread sheet here 13717 ..Clive

Greeny
26-10-2014, 12:51 PM
Hi Charlie

There is an 'improved' version of the ebay cyclone (a bit more expensive) at
http://www.ebay.co.uk/itm/Omni-Dust-Cyclone-ICE-workshop-vacuum-pre-filter-separation-wood-dust-powder-/181565313534?pt=LH_DefaultDomain_3&hash=item2a4622d1fe

video at
https://www.youtube.com/watch?v=kMmN0nrhdBE&feature=youtu.be
Looks pretty good.

Looking forward to seeing the first boards coming off your machine. :friendly_wink:
Greeny

charlieuk
26-10-2014, 01:12 PM
Cheers yea that what I had my eye on

charlieuk
09-12-2014, 09:47 PM
After a bit of experimenting I have ended up going with a high velocity low pressure bag style vacuum unit I got used of eBay nice and cheap and local. I thought this was the best solution because the foam dust is so light and the hvlp units are nice and quiet. The only thing now is trying to decide how to run the vacuum hose and in what size. The unit will be at one end of the 6meter table so can't decide if to run a solid pipe to the centre and then come down some how with something flexible or to have flexible the hole way on some sort of curtain rail type thing

EddyCurrent
09-12-2014, 10:25 PM
You want 4" pipe minimum I would think, 6" even. I would use solid pipe as much as possible, people use the 4" soil pipes. Flexible pipe has ridges where the metal spiral is and this restricts flow.
If you use plastic pipes you need to wrap some earth wire around them to drain static away, some people have experienced explosions.