thien or cyclone

[sunnybob]

Straight off, I have a cyclone, I know all about them and am NOT asking any questions about theory or operation.
I have a cyclone that uses 62 mm connectors. I want to increase the size of the separator to 100 mm because some material is still getting through.
I DONT want to spend several £100s on a factory unit and I am happy with my extractor,
so I have a straight comparison question hopefully to be answered by people who have tried both.
Do I find a large traffic cone and strengthen it?
or do I build a thien baffle and put it on top of a barre?l
YES, I know all about Bill Pentz thanks.

 

[MattRoberts]

I have both - a cyclone for my vac and a thien I built for my chip extractor.

The thien baffle was a lot more simple to make than I originally thought, and to be honest, I was amazed at how efficient it is.

Given it's a much smaller device for a 100mm extractor than an equivalent cyclone, and easily as efficient (if not more) I'd definitely recommend it over a cyclone

 

[Doug B]

I'm the opposite to Matt, I have a Thien & a cyclone both on shop vacs & the cyclone allows less through to the vac than the Thien regardless of how I set up the Thien.
That said both are better than not having a separator so which ever way you go you're on to a winner.

 

[MattRoberts]

Interesting - I wonder if it's because you're using it with a vac, and the speed of air is too high for the short height thien to be effective?

It could also be due to the design of the baffle - there are a few extra variables that can affect performance, such as the diameter, height, distance of the slot from the edge, width of the slot, diameter of the slot, depth of the vertical pipe...

 

[Rorschach]

Based on extensive research (seen lots of vids and forum articles lol) it would seem a Thien is best for larger chips as you you can have a compact unit with large holding capacity. Cyclones being better for finer dust at the expense of taking up more room and being prone to letting by larger clumps.

 

[graduate_owner]

This might be a daft comment but, since you already have a cyclone set up, could you fit a thein system as well? Would two drums be a better or worse situation? ( Space taken up, loss of suction from possible additional leaks, extra length of hoses etc).
Could be a 'now why didn't I think of such a brilliant idea' or like I said, could be totally daft. Probably the latter else people would already be doing it.

K

 

[sunnybob]

K... two systems would be too much flow reduction for my collector, not to mention space taken up.

Rorshach... You are right, although my cyclone is quite small (made from a medium sized traffic cone) its extremely efficient at fine dust collection, but I do get bigger shavings in the main bin. So that's 1 for thien.

Doug, I think if you your hoses are less than 62 mm they are too small for either system to work to a 100%.

Matt, I thnk your comments have tipped me to a thien. I have a 2 ft square floor space for this. I can go up to 8 ft tall, but really don't want to.

Thanks for all comments. looks like I have a thien to build.

 

[graduate_owner]

There are loads of youtube videos on this so you should find no problems there. I have been planning on making one as well ( together with Oland type turning tools, carbide tipped turning tools, improving my grinding rest etc etc - so many things, I'm sure you know the feeling).

Finally - daft idea then, I thought it would be!!


K

 

[sunnybob]

Not daft, just too much restriction for my particular extractor

 

[MattRoberts]

It wouldn't really work - both rely on gravity to separate particles, which means the intake is horizontal, and the suction is vertical. You'd have to offset them from each other to connect them up, which would be a very large footprint.

Bob - let me know if you want any pictures of mine or measurements for reference.

 

[sploo]

This subject interests me because I'm in the position of wanting one of those two but struggling for the space to fit in a cyclone.

I like Pentz's site because he does seem to have done a lot of research into what works and what doesn't. Conversely the Thien design seems to be a case of make something and see how it works (loads of variants, but of course few people trying multiple designs, or testing like for like against cyclones).

Pentz's research would seem to indicate that you do need a fairly large cyclone to make it efficient, as in; likely 22" dia and overall 8ft tall - unless you're in the 5hp territory in terms of motors. As such, I'd be surprised if a traffic cone sized separator would be good for 100mm pipe. I did make such a thing some years ago and it was mediocre.

My suggestion would be to build a moderately large Thien design, probably double height top hat. Cosmas Bauer (spelling?) has a variant with the outlet supporting the baffle and a hole in the side of that pipe. I've never managed to get out of him from where he came up with that design and how it compares though.

 

[sunnybob]

Matt, I would be interested in overall measurements at this stage. If I have enough room I might well ask for more details, thanks.

 

[sploo]

Matt, I would be interested in overall measurements at this stage. If I have enough room I might well ask for more details, thanks.

+1 to that.

 

[siggy_7]

When you say your cyclone is "letting stuff through" do you mean larger shavings or fine dust? A properly sized and designed cyclone should give superior performance to a thien baffle for fine dust separation, but both should be 100% effective at removing shavings. You don't state what extractor you are using this with or how big and what deign your current cyclone is - any details? Does your current cyclone have an intake ramp?

Series connection of separators not a good idea, you just reduce flow in the system overall. The problem is likely to be your existing separator is not sized correctly or has some design issue - better to have one separator that is working efficiently.

Sent from my SM-N910F using Tapatalk

 

[sunnybob]

yes, my current cyclone is undersized as stated above. 4" from the extractor through a 3" cyclone causes the large shavings to go through, that's why I need to decide whether to make a bigger cyclone or a thien baffle.
Looking at commercially made 4" cyclones they are extremely space demanding. I think a thien will take up a lot less floor space.

 

[siggy_7]

A cyclone is sized by a lot more than just the inlet diameter though - did you make or buy? I presume you are using a high flow extractor - what size is it?

Sent from my SM-N910F using Tapatalk

 

[sploo]

yes, my current cyclone is undersized as stated above. 4" from the extractor through a 3" cyclone causes the large shavings to go through, that's why I need to decide whether to make a bigger cyclone or a thien baffle.
Looking at commercially made 4" cyclones they are extremely space demanding. I think a thien will take up a lot less floor space.

At least for the diy versions, it looks to me that the main difference in size is height rather than floor space - both likely need a cylinder of a similar diameter, both really need a filter stack next to the drum (unless venting outside). The main difference is that an efficiently sized cyclone (for a home workshop environment) ends up being quite tall, and isn't really feasible with less than an 8' tall ceiling.

 

[MattRoberts]

Matt, I would be interested in overall measurements at this stage. If I have enough room I might well ask for more details, thanks.

Hi mate, they're as follows:

Outer Diameter 54cm
Inner diameter 34cm
Internal Height 16.5cm

 

[sunnybob]

Matt, that motor of yours looks a dam sight bigger than my 1.5 hp sip.
I considered the cyclone central as per peter purfit, but I've looked several times in the last year and they are always out of stock, apart from the £200 plus price tag (would you believe I got a quote from them to ship the flat pack to Cyprus and they wanted ANOTHER £200 plus?)

I think I will make a thien, purely for the fun of it, but first I need to get a bigger sturdier barrel for the waste because the plastic ikea box I'm using at the moment wont take the vacuum..

Wont be able to start till late next week as I am still in the uK visiting family, but I'll keep a record of the build.

 

[MattRoberts]

It's only a 2hp.

Where in the uk are you? I have a bunch of the clear plastic left over, and am 10 mins from Gatwick. You're welcome to some.

Cheers