Thread: Dust Extraction - Cyclone

Pat,

Thanks, glad I could help.

bill

When I empty my Cyclone bin, I empty it into a plastic garbage bag as I believe it is an offence in Oz to just put dust in a Council Bin unwrapped.

Could you put a plastic bag inside your catch bin?

I believe so just havent done it yet - might do that on the weekend.

Question for Bill if I may.

Bill, in the XLS spreadsheet (metric) in the drawing for the Air Ramp, there is some text "This value adjusted by Testing to current value calculates in error!" - pray tell, what does this mean?

Gordon.

Zymurgy,

The air ramp or a variation is often given to college math students as one of those nasty test problems. It turns out you can not solve this one quite so easily. Its length is easy to calculate as the diagonal of a right triangle with height equal to the height of the inlet and width the circumference of the cylinder it touches. Unfortunately it is really not a circle at all but instead a spiral moving around a cylinder. When you collapse that into a circle you end up with only about 345 degrees of rotation. Anyhow I only have a couple of three engineering degrees and a big hammer so I came up with a calculation that gets close enough that some solder or sealant will do the rest. Sorry I should have translated that better on the drawing. In fact, please forgive, but I did some more tweaking on the Imperial version that actually makes the ramp even a closer fit. You might want to run your numbers through that then translate back to metric.

Sorry for the confusion and would be happy if you can give me a better solution.

bill

Wayne,

A little heads-up on the plastic bag. An air leak in the drum or connection with pull that plastic bag right inside the cyclone in a jiffy. Either put in a liner or a weight in the bottom to avoid losing an impeller and potentially a motor. I prefer the liner that easily slips out unless you have a lot of rocks or bricks to throw away. A piece of stiff plastic, the bendable 1/8" ply, or even cardboard can work as the liner to go around the inside of the bag to hold it tight to your collection bin sides. The more springy the better.

bill

Bill,

Thanks. Yes, I had thought of that (I had a plastic bag get sucked straight through the system and out the Outlet!). Guess I should have pointed out I was going to place something heavy in the bottom of the bag. Might try out the Liner idea sometime.

I'm not all that worried as I empty the bin into a compost bin which just happens to be the same diameter as the Cyclone Bin. I put on a mask and tip it straight over - hardly anything gets out.

Hows the new page going?

Wayne,

No problem on the bag then, just wanted to save you some grief.

That page on Airflow Measurement is near done, have a couple of more graphics to do with just place holder in the spot on how to record values right now. Still waiting for feedback from a couple of my air engineer friends to make sure nothing too far off before sharing with the world. Will soon post it on Wood Central for their shakedown, then will rename it and move it from its current temporary location and put it in my collection of Dust Collection and Cyclone pages.

bill

Bill,

It's looks/reads great (I read it the night you sent it to me).

Just going back a little bit guys,
when you pump the dust from the filters through the cleaning outlet & down your hose extension, would a water hose on fine mist or a sprinkler stop the dust flying off into the ether to bother neighbours or, even worse, the rugrats? I have a tiny backyard and I can imagine the fine dust settling on the grass & trees etc to snag on my tin lids when they’re running. My family is the main reason I will build a cyclone (my little man has asthma plus SWMBO and the eldest are both very sensitive to dust etc).

Just a thought.

Pat

Pat,

I only get a few tablespoons of dust in my filters from a full barrel. After maybe 10 to 15 barrels I can send that dust out into the front yard grass and it totally vanishes. Alternatively, with a HEPA filter on my shop vac I could just vacuum it out then dump it in a bag in my garbage if needed. In either case I'd keep it well away from my family and me.

bill

Everyone,

I (and probably Bill too) have been getting quite a few questions about the building process by PM and email. That's find and I don't mind helping.

But I thought I would mention that Bill now has full instructions (very, very detailed) on his site but you may not have noticed them as they are down in the depths. So, here's a link:

http://cnets.net/~eclectic/woodworki...ldCyclone.html

I think it answers just about everything.

Cheers,

All,

If anyone is interested, I have finally setup my personal Web Page with, principally, info on building a Cyclone. Most of the Pics you will have seen in this thread but it is all in one place and (a bit) organised. This is a work-in-progress and will get better (more text) over time.

Check it out at:
http://members.optusnet.com.au/~wayne_davy/

Cheers,