Thread: The Tale of the Twenty Dollar Cyclone (not yet a saga, but we're working on it.)

It's the later one, Peter.

Originally Posted by aldav

Correct. And get rid of that nib of plastic on the edge of the outlet as well. The tube that you've extended into the cyclone inlet shouldn't have any deleterious impact on performance so you might as well leave it. It actually probably helps with preventing some dust from stalling in the top of the cone.

Well I've swapped the ply for a bit of 3mm mdf (temporarily), and have cleaned off the nibs left over from the moulding.

Today's results are encouraging, but still nowhere near the "98%" mark I'm expecting. The actual numbers (my sample is shrinking due to natural attrition and being caught in the filter!) are 35gms in the vac and 138 in the bucket. That's so very close to 80% I'll round it up.

Next step is to remove my modification at the entrance to see if that makes a difference.

At 80% it's probably still not worth doing, but let's see!

Thanks @aldav - I appreciate the input!

Cheers,

P

Originally Posted by aldav

And get rid of that nib of plastic on the edge of the outlet as well.

Now @aldav, I'm not blaming you for this at all, but it might have been nice to suggest that in my excitement I don't connect the thing in back to front! Your suggestion worked so well that the improvement mentioned above worked in REVERSE!

So, with the hoses connected in the correct direction, I'm now at 97.2%, which is not 98, but right in the middle of @BobL's Dust Deputy figures and I can probably live with that! I will now shorten the hose between vac and cyclone, and see what difference that makes.

I don't think I'll take out the plastic insert on the inlet as it did make a measurable improvement, but I won't proceed with the 3d printed "ramp" at this stage as I doubt that will impact at all on the fine dust.

This is not the end of this thread however, I'm going to tidy up the installation with a few 3d printed bits, and get a HEPA filter for the Ryobi (the old Jet one won't fit).

I'll leave this post for now with a piece of Bob's earlier quote - because it's important!

Originally Posted by BobL

My testing found a small cyclone like that (a dust deputy) was able to removed between 96.5 and 98.75% of the sawdust.
My setup was a Ryobi W&D shop vac and a dust deputy on top of a 20L bucket and I always empty the bucket before it gets more than 20% full.

Don't be fooled into thinking the vac filters will trap all of the (most health significant) fine dust that gets past the cyclone.
The greatest percentage of PM2.5 dust produce by wood processing is quite small, ie <1% but this is the stuff to worry about especially as only very small amounts are needed to contaminate sheds and a significant proportion will pass straight through most basic vac filters. Another good reason to locate or vent vacs outside.

Thank you to all who have contributed!

Originally Posted by bitingmidge

Now @aldav, I'm not blaming you for this at all, but it might have been nice to suggest that in my excitement I don't connect the thing in back to front! Your suggestion worked so well that the improvement mentioned above worked in REVERSE!

This reminds me of when I was given a well used, 92cc Stihl chainsaw with a seized piston. I replaced the piston and cylinder and it fired up after about 3 pulls of the starter cord and ran strongly. I then tidied it up, put a bar and chain on it, quickly took some photos and proudly posted pics of it on a (fairly redneck) US chain saw forum. Someone spotted that I had the chain on backwards and then the jokes started and it took weeks to die away. Things like "like water down a plug hole. chainsaw chains must go around the other way in the southern hemisphere" etc.

Another one was a member here who bought a negative raked TS blade for cutting Al and was wondering why it was not cutting - yeah, blade on backwards - gain.

First thing in the morning I issued a newly sharpened saw blade to one of my workers to fit and then rip some chipboard sheets. At morning tea, after two hours cutting, he said that the sharpener that we were using was hopeless as he really had to push hard to get the saw to cut.

Checked the blade and he had it on backwards.

Originally Posted by bitingmidge

Now @aldav, I'm not blaming you for this at all, but it might have been nice to suggest that in my excitement I don't connect the thing in back to front! Your suggestion worked so well that the improvement mentioned above worked in REVERSE!

You're not the first and you won't be the last! For that setup to work you need to blow into the inlet, not suck out of it. There are people who use these small cyclones that way, but not for woodwork. I'm impressed that you owned up to it. I won't tell you about all the dumb things I've done as I don't have sufficient time available, though I note that a few other people are happy to share.

One place where things can easily go in reverse if not wired correctly are 3P motors. Reversing 3P motors is easy - just swap any two of the phases.

On the old 3P RAS at the mens shed I installed a 3P - 3P VFD and a braking resistor. When I fired it up I was all focused on the speckky braking operation and did not check direction. Then before shed member use the usually very competent shed sparky (60 years of sparky experience) gave it the once over. I went home and a hour or so later I get a call from the shed management - saw is not cutting and making a lot of smoke. I knew immediately what it was and went back and swapped two of the phases on the input - still going teh wrong way. Then it dawned on me - the VFD converts all the input power to DC and then makes the 3 phases from that. Have to swap the VFD output phases. WHALA!

A small update.

Because I had the old Jet Bucket, and it had a big hole and six smaller holes to fit the M6 bolts that held the now recycled motor on the lid, it was clearly the perfect candidate for the vacuum bucket. As noted above, my first attempt using 12mm ply was an abject failure, my second using 3mm MDF a success, but hardly beautiful.

So in less time than it took to say "let's go to Bunnings to find something better" I had a new flash infill drawn and printing underway. The nice thing about 3d printing is the opposite of one of the nice things about working with wood - there is a total disconnect with the production process once the print is underway, leaving one to get on with other things, while one's handiwork is slowly coming into being.

Yes, it's a bit of overkill, but it looks like a bought part and it cost less than $5.00, so who can complain?

21-01- 07 at 09-06-26.jpg

Sorted! (Yes, I did build a small disk base of MDF fitted with chair casters and gave it a single clear coat while the printing was happening.)

Cheers,

P

Wow, that really looks like a professional install.