I love cyclonic vacuums. A lot. I've had Dyson cyclone for about 4 years now and recently i pulled the wash every 6 months HEPA filter out for the first time and it was perfectly clean. I was shocked, that's efficient cyclone! That vacuum has been used and abused over its life from sucking up superfine MDF and plaster dust to dirt, screws and leaves and it has not failed yet.
I've (and possibly my neighbours) of having to take the filter out of the shop vac every couple of empties to take it out into the yard and blowing it out with compressed air. Usually creating giant dust clouds.
So I decided to add a cyclone to my shop vac. The cheapest available solution that I could find was a Dust deputy which was $85 just for the cyclone, no bucket or hoses were included. The full kit was $179. Considering i only paid $30 for my shop vac that seemed a little pricey. The other day on eBay i noticed a Chinese clone of the dust deputy for $50. Still more then I wanted to pay, but I really wanted to stop having to clean that damn filter, so I bought it. I have made one before but it would be really fiddly to make one that small.
I started with making a little trolley to hold it all and used the wheels from the shop vac to make it mobile. Added a handle to make it easy to move around. The cyclone is bolted to a sheet of 12 mm ply and held down to a 30l bucket with bungee straps with some weather strip added between the ply and the bucket to achieve a good seal. Lastly the vac was screwed down to the base, I don't plan on having to empty the vac very often so I don't mind undoing a couple of screws to do that.
I tested it buy sucking up about 10l of stuff that I had emptied from the shop vac. Opened the shop vac and it was perfectly clean! Yay!
The Finished result.