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Jackson
26th January 2004, 11:43 AM
I am hoping to make a dust extractor on the cheap, but I am having more difficulty than I thought. I have an old vacuum cleaner that I was going to use the motor from, mounted so that it sucks out a hole in the bottom of a sealed 20 litre drum. I was then going to use a flexible hose (like a pool hose) from the top of the drum to the work. However when I tried just using the vacuum cleaner to suck dust I found it was not doing the job. I don't know if the standard vacuum nozzle doesn't work for air borne dust or whether there is simply not enough grunt. I suspect it's the latter.

Has anyone got any advice on this one? I remember seeing an article in (I think) the Australian Woodworker years ago in which I recall the author had mounted a holden fan assembly in the base of a drum. Regretably I don't have any old holdens lying around.

Any ideas, or even plans, would be appreciated.

Mark J

DanP
26th January 2004, 12:19 PM
Jacko,

Do a search at the top for 'cyclone' or do a search on member Wayne Davy. He is the guru of dust extraction here. His site will probably have the plans you are after and if it doesn't, it will have links to Bill Pentz's site which definately does have the plans and many other hints and tips relating to dust extraction.

Dan

Sturdee
26th January 2004, 04:21 PM
Jacko,

I think what you want to build is more like a mini cyclone similar to my Triton Dust Bucket conversion. Do a search on this web for more details. If you don't have a dust bucket it could also be made using 2 paint drums.


Peter.

Red neck
26th January 2004, 05:10 PM
Mark


I use a 1hp dust collector specifically for the bandsaw and lathe. Firstly to recover a high percentage of shavings; secondly to stream away dust when sanding. I also use a floor sweep to simplify the final mess ‘clean-up’. The machine sits between the bandsaw and the lathe and relies on a four-inch hose. It also serves as a mobile unit for the router and drop mitre saw. The amount of waste material recovered is significantly more than I recover in my 2hp machine connected to the jointer, table-saw. thicknesser etc.

I have used a vacuum cleaner on palm-sanders and other small tools. In such instances the vacuum motor with its high RPM, low power drives a small turbine delivering high suction to a small volume of air at high velocity. The hose is connected directly to the dust producer. Efficiency deteriorates as the extremely small particles block the bag thereby reducing suction. I have tried it through a Triton dust bucket and found the same problem with the Triton filter screen.

In contrast the DC moves a large mass of air at a slower velocity. To achieve this it uses a larger motor driving a 12 inch or more diameter turbine/impeller disk. The top bag is capable of exhausting hundreds of cubic feet more airflow than the outlet of a vacuum cleaner. It is this high-mass airflow that is capable of plucking dust particles a short distance from the point that they part from the workpiece.

The use of a cyclone provides an intermediate point to collect large particles without filling the bottom bag of your dust collector. The small particles still flow to the top and bottom bags of the DC eventually compromising the outflow capabilities of the top bag. This is overcome by shaking the top bag each day before use or using a pleated filter in lieu of the top bag. I don’t believe the cyclone improves the efficiency of the unit given that this is dictated by the size of the motor and turbine and the diameter and length of plumbing.

Personally I believe that for a few hundred dollars a 1hp unit is adequate for the requirements of woodturning. My own machine, a Delta, had a small grill at the impeller inlet to prevent large items fouling the impeller (like your chuck spanner). I found that the size of wood shavings from the lathe quickly fouled the grill and blocked the flow necessitating removal of the plumbing to clear it. I removed the grill with tin-snips and ‘risk-managed’ my inlets!

col2
26th January 2004, 10:51 PM
Sounds like I've got a similar machine to Red Neck, altho mine was from Hare & Forbes. I played with vacuum cleaners a bit, including thinking about a cyclone, inspired by the posts on the forum, but in the end I spent the money ($179 plus the hose).

I've got it hooked up with 4" sewer pipe with a pipe along the wall behind the lathe and the bandsaw, and a length of flexible hose to each. I used a stormwater downpipe adapter (90mm round to 100mm x 75 rectangular) as a connector between a sheet metal nozzle and the flexible hoze. Works well, altho I only have one machine connected at a time, to get the maximum suction. I just pull the hose out of the pipe and put a turned MDF plug in the pipe on the end which serves the machine I am not using at the time. Blast gates would be better, but that's another project.

I think in the end, the DC will do a better job for the money and the time.

cheers

Colin

Tonyz
28th January 2004, 06:38 PM
IF I see 1 more question about Dust I'll bloody scream. PLEASE PLEASE do a SEARCH on dust collectors /minicyclones etc Ive done it myself and there is more intelligence in these threads the Canberra

outback
28th January 2004, 06:44 PM
Hey Tonto, Isn't there a thread somewhere 'bout using the search? Maybe I should use the search function to see if using the search function has been suggested, I luv it. :D :D



P.S. Does the intelligence of this post mean I am intelligent enough or too intelligent for Canberra? :rolleyes: :confused:

Tonyz
29th January 2004, 09:46 PM
grovell,grovell, oh most mighty one I was implying those that live[?] on the 'hill' although by your script at the bottom you could be implying the same

ozwinner
30th January 2004, 07:20 AM
I agree with useing the search button, but if everyone used it who would we talk to?
All you would hear is the crickets.
http://www.my-smileys.de/smileys_1/grin.gif

DanP
30th January 2004, 12:40 PM
I like it the way it is and I think all the sooks whinging about people not using the search engine should try and add something valuable. If people did not want to answer, they wouldn't. Let people ask their questions and those who want to answer will and those who don't because someone asked it before, THEN DON'T.

Dan

Sir Stinkalot
30th January 2004, 01:17 PM
I agree .... the search button is handy but often new ideas by new and old members are added when the same question is asked again. It is also a good way to be introduced into a topic that you may not have been interested or known about before. It is difficult to search for a post that you don't know the subject of but it is sometimes handy to it pop up in the new posts.
I find that if you can find your way onto the "who's online" section it is interesting to see which posts people are reading and often they are from a few years ago that are worth having a look over again.

Shekel
30th January 2004, 03:46 PM
If you really want to get serious and save yourself some searching, try


http://cnets.net/~eclectic/woodworking/cyclone/index.cfm

regards,
Shekel

ozwinner
30th January 2004, 04:16 PM
The search button is about a useful as a dicturny, dictioniaer, dictio, ohhh bugger it.
If you cant spell it you cant find it.
Cheers, Al the Speel wizard.

Jackson
1st February 2004, 11:14 AM
Thanks folks for the information on dust extraction. (thanks Dan P, Peter, Redneck and Colin)

Sorry Tonto for touching a sore point. I am a bit new to the board and hadn't explored all the functions yet. For instance, I didn't didn't even know you were compelled to read posts of no interest to you!


Jacko

silentC
2nd February 2004, 10:22 AM
I didn't didn't even know you were compelled to read posts of no interest to you!

Touche!! Well put Jacko :D :D :D