Most unusual Bill Pentz style cyclone ever?

[Allan Stirling]

I have desperately wanted a cyclone dust collector for some time - And I just finished mine.

I saw and liked the look of Bill Pentz's design - So I took his spreadsheet, put all my figures in and saw into the future.

This is not one of those "step by step beautiful pictures, doing everything as per the instructions" blogs. If you want that, I would suggest going here:
http://www.ablett.jp/workshop/cyclone.htm

It's also not a standard build. You see, I have very little experience of metal. Added to that, sheet metal is fairly expensive here. And I like a challenge. I also have a reasonably well equipped woodshop. So I made it out of lumber.

So I bought some 21x120mmx5.4m (8 lengths) of "redwood" - or at least that's what it's called here.

I also bought a "Clarke 3hp chip collector - 2200w". Uhhh... Sure it is is all I have to say to that. It draws 1300w with no intake restriction, as stock.



For the cyclone cone, which I made first, I calculated out the circumference of the top and bottom of the cone, accounting for the material thickess, then divided those figures by 50. This gives me the inner wall dimensions of each piece. A small jig for angle cutting on the table saw then meant that (after 50 cuts) I had my bare cone. Another 50 cuts later, I added the 7.2 degree offset cut to form the final shape of each of the segments.

I could have at this point done the right thing and biscuit jointed the whole thing. I didn't - I glued it and butt jointed it then clamped it up TIGHT with "ducting worm drive clips".

I used the same assembly technique for the air-ramp cylinder.

Both of these were then sanded (sandpaper flap disk, lots of time, lots of dust collected in the trusty dyson)

For the outlet tube, I also went cheap. I bought some "lining paper" - Which is thick, untextured wallpaper. It's designed to cover up cheap poured concrete walls. It also has the design aim of having essentially 0 moisture expansion. So, make a couple of wooden rings out of plywood on my circle cutting jig with the bandsaw, join these together to make a tube form. Wrap the paper round the tube form to make sure you're going straight, then unwrap and evenly paint on some waterproof PVA. Roll the former onwards and paint another section. Keep going until you have your desired wall thickness.

The air-ramp was some plywood, cut to the specifications from Bill's wonderful spreadsheet, then steam-bent into mostly the right shape.

The air inlet tube is a simple wooden tube, made from 4 pieces of wood cut to the cutting diagram (remembering to account for material thickness), glued up and then sanded down where necessary to form space for the air ramp and the outlet tube. At some points, the thickness of the tube is 5mm or so, but that's not at the outside wall, so shouldn't matter too much.

I then put all of the air-ramp cylinder together - Which took some cutting and recutting to get the angles right. I hadn't properly calculated for thickness when cutting my air-entry hole

At this point, I wrapped the inside of the air-ramp cylinder with UHMWPE tape. If you haven't seen this stuff - I suggest looking for somewhere that will supply it. It's great for anything that needs to slide. It's used in bulletproof vests, tablesaw guides, etc.



Wrapping the inside of the cone is rather more difficult - Since there are no straight lines. It's possible, though.

For the dust collection bin, I used... A bin. It's cheap, it's plastic and it'll probably get replaced soon with a proper metal one. On the plus side, it was easy to cut the hole for the dust inlet, seal it with hot-melt glue and seal round the perimeter.

To put it all together, the blower motor is mounted first - to the joists in the garage, with a fairly chunky amount of reinforcement in case of a material hit jamming the impeller.

I am incredibly lucky in having a shop (my girlfriend prefers to call it a garage, since it's where the car is meant to go) that has a sloping roof - the rafters of which are exposed. So at the tallest point, it's 4.5m tall.

So waaay up there, fixing the blower motor almost at roof level. A bike hoist was used to lift it initially, then manhandled into position. The same bike hoist was rearranged to allow me to pull the body of the cyclone up.




So that's where I am now. What's with the wooden box above the bin? Well, first test suck sent it flying roofwards. It's not ideal, but it holds it all down.

For anyone else considering this - Don't use cheap flexible ducting. It's not up to the job and exhibits too much loss - at least for the inlet tube. I still need to get real ducting.

Cheers,

Allan.

[Jim O'Dell]

COOL!!! Now for the big question, how does it work? Thanks for the pictures! Lots of time and calculations went into that. Jim.

[Bill Arnold]

That's amazing, Allan!

(...and I thought having to assemble my SDG was a task!)

[Doug Shepard]

Very cool. I was originally going to stick my cyclone up in the same space too but managed to reclaim some space down below when a furnace got removed from the garage. All my main ducting is up in that space though. You might want to check out my "remote" blastgate fix if you need something similar
http://www.sawmillcreek.org/showthread.php?t=58586
Those have worked out extremely well.

[David Hostetler]

Very cool setup!

Is it just me or does that Clarke "chip collector" look an awful lot like the Central Machinery 3Hp unit from Harbor Freight?
http://www.harborfreight.com/cpi/cta...emnumber=98872

[glenn bradley]

Excellent. I love it.

[Jamie Buxton]

That is wonderful. I've often wondered about my fellow woodworkers who build a cyclone from metal. They know lots about working wood, and little about metal. They have tools to work wood, and little to work metal. Wood seems like an obvious choice. I'm glad to see that at least one person sees it my way!

[Scott Hildenbrand]

You made it out of wood??? AWESOME!

Need to make yourself some nice brass rings and rivet them in place.. Give it a good sanding and finish.

So, obvious "wow" aside.. How does it work? Lets see some filled bin pictures..

[Josiah Bartlett]

I really like how you mounted the cyclone in the rafters and then ran a long hose down to the bin, it makes it easy to empty. I think I'm going to do that too. I have a 12/12 pitch with trusses up there and its practically useless space except for stuff like this.

[Allan Stirling]

Thanks, everyone!

To answer some of the questions:

It works really well - I don't have any easy way of measuring the throughput, but it's not too far off the blower on its own.

Dust separation is exceptional - I ran it with no filters and inlet just suspended mid-room (it blew the dust from the tops of the rafters) - It collected probably 100ml of dust.

I am willing to bet there's a factory somewhere producing exactly the same blower for shipping all over the world - Unfinished. All the distributor has to do is paint it and put a sticker on it.

Be careful if you intend to run a tube down to the bin - the blower WILL crush it if you push it too hard. Use mainly spiral-wound solid tube, then terminate in a very short length of flexible tube. Air resistance doesn't matter here, since there should be no real moving air there. However, dust does become trapped in the accordion shaped ridges.

Cheers,

Allan.

[Allan Stirling]

Doh. I forgot the costs.

"3HP" chip collector: £300
Lumber: £60
Ducting worm drive clips: £14
8" flexible ducting: £8
Wallpaper ("lining paper"): £3
Glue: £6
30m x 75mm UHMWPE tape: £80

Total: £471

[Gary Kvasnicka]

I thought of building a wood strip cyclone, bead and cove like I build kayaks, then I thought nah that won't work. You proved that wrong and gave me another project to add to the list. Thanks!
Great job!

BTW do you have pics of the cylinder to cone transition, when I was "designing" mine in my head, it was the stumbling point in my construction method.

[Doug Carpenter]

That is really cool.

I'm thinking that some of that could be done with wiggle wood.

Also a sonotube would come in hady as well.

Makes me think........

[Anthony Whitesell]

Originally Posted by David Hostetler

Very cool setup!

Is it just me or does that Clarke "chip collector" look an awful lot like the Central Machinery 3Hp unit from Harbor Freight?
http://www.harborfreight.com/cpi/cta...emnumber=98872

Are you sure that's Harbor Freight Central Machinery and not Woodworker's Supply Woodtek brand? Hehehe.

[Thomas Pender]

Also, what amounts to first class coopering skills. I would be tempted to put a brass or steel band around it for appearance.

For me, the thing I have the least of is time. So, Oneida won. I only wish I could do somehting as innovative as what you did.