Nothing particularly tricky or major skills needed to make it but I used a variety of power tools to get to the conclusion. That is not to say you couldn't do it with only hand tools. The most valuable tool here in my humble opinion is my hot melt glue gun!!!
So here is the processes I went through to build it.
1. Witches hat/safety cone
2. A barrel with a tight fitting lid that MUST be very rigid.
3. 1 metre length of 50mm DWV pipe
4. 2 X 50mm-40mm reducer
5. Assorted ½ inch Plywood to make 2 rings and plug for the top of the cone.
6. Screws to suit
7. 50mm X 1000mm X 3mm Aluminium strap (optional but kind necessary for rigidity)
8. 6mm nuts and bolts for Aluminium strap above.
9. Vacuum tube to attach the cyclone…I had several lying around and I joined them together to make a big hose.
10. Self-Adhesive foam tape to seal the “plug” for the top of the cone.
11. Nuts and bolts to secure the input tube to the inlet of the cone.
The cone cost me $11 and the plastic pipe and fittings was about $10 but if you have the bits around your shop you could probably build it for zero cost.
To the build:
1. Start by laying out the plug for the top of the witches hat. The Bunnings one has raised circles in each corner and to keep this structural integrity I left these in tact.
2. Here is the shaped plate that forms the plug on the top of the cyclone. It is just a square plate with the corners radiused to suit the plastic ring reinforcement as seen I made this from ½ ″ plywood .
3. This is the 50mm-40mm reducer purchased from a hardware store or plumbing store. Funnily enough I use a 2″ Forstner bit and the 40mm side of the reducer makes a very snug fit (but if you are somewhere that does inches convert to a suitable size)
4. This is the 50mm DWF pipe cut on a 45°angle and it helps set out the hole that you need to cut out on the side angle. It is approximately 400mm long.
5. As can be seen it is an egg or elongated teardrop shape that equates to the pipe entering close to the side on an angle. I marked it with a marker pen and drilled a series of connective holes that I then used a Stanley knife to “join the dots” and cut the hole.
7. Pic shows the finished pipe bolted to the cone with its final shape which follows the contour of the cone.
8. Pic shows the plug from underneath with the 50-40 reducer fitted in the hole. For my own curiosity and so I could tune the cyclone effect I fitted a small Perspex window through which I can observe the inner workings. It is this 50mm socket that you insert a 150mm long section of the pipe. This is where the vacuum connects to.
9. Pic shows the ¼ ″ adhesive backed foam that I happened to have on hand – this is to ensure a tight fit when sealing against the witches hat. I used Button headed stitching screws with integral washers from the edge of the cone on the top. There is not a lot of room so measure twice – cut once.
10. Here is the lid of the drum I used.
11. Pics shows the hot glue gun in action sealing up the small gap between the cone and the input tube. If you have a big gap, build it up in layers, allowing each layer to cool before putting the next one on top [POSSIBLE BURN HAZARD – BE CAREFUL]. I used the glue gun on the outside and the inside to make sure that there were no gaps or holes, which will severely reduce the performance.
13. Here is the two plywood discs and the lid with its 80mm hole cut in the centre. I used an 80mm hole saw I had on hand but if you have a 90mm or 75mm use that – it is not that critical as all this does is funnel the waste into the barrel. FYI to make the discs on the lathe I rough cut a circle on my table saw, drilled a hole and mounted it to the chuck using a screw mount. After ensuring the right size and making sure it cleared my hump, I then utilize this hole to be the guide hole for my holesaw mounted in the drill.
14. This is the money shot…. As can be seen the plywood sandwich is assembled through the lid and the witches hat which was cut to just protrude in to the hole (dependent on the size of your hole saw) has been screwed into this sandwich through the sides of the cone as per the diagram. This sandwich has added a significant level of rigidity and solidness to the otherwise flimsy plastic lid, and it gives a very solid platform to screw the cone to and ensure it doesn't flop about.
15. Pic from the top of the cone into the lid assembly before it is sealed tight with hot melt glue forming an airtight seal for the barrel.
16. Looking up the cyclone we can see the 150mm pipe installed in step 8
18. This shows us after the lid is fully sealed on the top intersection.
19. Shown here is my plastic barrel. I found this on a hard rubbish pile near my home. It is a stout barrel with very stiff sides…but not stiff enough as it turns out. The first time I tested the cyclone and I blocked the intake hose the sides of the barrel buckled in from the suction!!! Truly very strong!!! This is the modification I performed to reinforce the sides of my barrel to prevent it from buckling. It is 3mm thick 50mm wide aluminium strap that I curved into the shape of the barrel and then drilled and screwed every 75mm and fixed with nuts and bolts. This prevents the sides from buckling, but it now makes the lid move up and down when you block the intake pipe. A top tip to bend the strap – open your woodworking vise and use the rods to trap the metal, bend it a bit, move it a bit, bend it a bit until you have a circle formed.
20. pics shows the assembly mounted to the drum with the metal clamp fitted and an airtight bond ready to use!
21. pic shows the inlet tube with the vacuum cleaner hose fitted to it.
22. pic shows the full height of the assembled cyclone – it stands about a metre tall.
23. pic shows it with the vacuum cleaned attached and the inlet tube with it’s recycled vacuum cleaner hose as repossessed from a hard rubbish pile connected with the second 50mm-40mm reducer on the end of the inlet pipe.
24. Connect it all up and get cleaning!!!
Postscript: I have found the Vacuum cleaner works a bit hard with the 1 1/4" vacuum cleaner hoses - so I purchased some 2" hose to give the vacuum a longer life. This sucks insanely hard and as mentioned it can deform the side of the drum so make sure you find one with really stiff walls or it could collapse!