Thein seperator intake positioning, and other problems

[Grahamshed]

hi guys
I have just built myself a separator for the camvac but only getting partial success.
About 80 percent of the fine dust is going into the bin, sort of, but the other 20 percent is still reaching the vac, and that is way to much.
Proper Thein separators, you know, the expensive ones, have a side entry intake. I didn't fancy doing that so I have a top entry and then a flexible pipe directing the dust along the wall.... which should have the same effect but I do not think I am actually getting the 'cyclone'. A good deal of the dust stays in the 'top hat' in the centre of the base instead of going down the two slots.

Perhaps I should explain my setup. I have a plastic bin, to hopefully hold the dust, with another bin jammed in the top of it. This top bin has the two slots cut around the base for the dust to fall into the lower bin.
I am wondering......
1... does the depth of the bin you are using have a bearing ? my 2 bins are each about 18 / 20 inches tall.
2... do Thein separators really work with fine dust or only heavier particles ?
All the videos I have seen sjow NO dust getting to the main vac. What am I doing wrong ?

 

[Graham Orm]

This is my first one. http://www.youtube.com/watch?v=UopsGH-Yzf4 It worked perfectly and as you can see when the top is removed it shifted fine suspended dust, also visible zero dust or particles in the vac. I've made a better version now and created an inlet duct from layered ply. I'll take a pic if you like. It works exactly the same way.

 

[Grahamshed]

Hi Graham. A pic of your new inlet duct would be very useful. In the meantime I see that your slots in the base are considerably bigger than mine so I will enlarge them and see if that helps.
The bit I cannot get my head around is why the exit hose to the vac doesn't just suck in dust from the 'cyclone'.... it seems like that is what mine may be doing.

 

[Grahamshed]

Ok, so I have made the slots considerably bigger ( in two stages ) and I am now down to a teaspoon full of very fine dust reaching the vac ( out of about half a bucket full in the test ) . Should I be happy with that ? Graham, Is it worth making them bigger still ? do you really get ZERO dust in yours ?

 

[Graham Orm]

To be honest I've not looked that closely, but i would probably be happy with that miniscule amount. When I check the vac, usually about every other empty of the bucket there's nothing at all. Are you creating a cyclone effect? Does the dust fire round the bin?

By the way Matthias Wandel reckons that it will work without the Thein baffle, but I've not tried it.

 

[Graham Orm]

Hi Graham. A pic of your new inlet duct would be very useful. In the meantime I see that your slots in the base are considerably bigger than mine so I will enlarge them and see if that helps.
The bit I cannot get my head around is why the exit hose to the vac doesn't just suck in dust from the 'cyclone'.... it seems like that is what mine may be doing.

The cyclone makes it fly out to the sides and spiral down. Your vac hose should draw air through the centre. I'll take a pic and post it.

 

[Grahamshed]

Are you creating a cyclone effect? Does the dust fire round the bin?

By the way Matthias Wandel reckons that it will work without the Thein baffle, but I've not tried it.

I really don't know about the cyclone. The tubing ends up bending around the inside of the drum when I put the lid on so if it stays put when the vac is turned on it should create one. I will see if I can persuade swimbo to get inside and check.

With so much of the baffle being lost to the slots I also have my doubts if it is serving any real purpose.

 

[Graham Orm]

The new model.

 

[Grahamshed]

Thanks for the pictures Graham, I may well copy that intake idea at some stage.