Dust Extractor Switching

[Chris Parks]

I am putting together a cyclone system hooked up to multiple machines and started to think about the problem of controlling it from multiple points. A remote control was out as I would lose the damned thing the first time I used it. I thought about switches on gates but discarded that as the gate has to be moved every time to switch it on and off and pneumatics got the flick on compexity issues. I decided to use an overhead switch (the type with a cord) that controlled a low voltage (24Volt) circuit which in turn fired up the cyclone. All the wiring runs through the ducting to keep things neat and the cord is at arms reach above each machine. Just another idea to add to for those thinking of installing a system and wondering about switching it.

[Alan Schaffter]

I am putting together a cyclone system hooked up to multiple machines and started to think about the problem of controlling it from multiple points.

Chris, not to make more work for you, but you realize that you have only solved part of your problem. Unless you use a three wire low voltage control circuit, you will need to remember which switch cord you pulled and go back to that specific one to turn the DC off. Since you are using a contactor with a low voltage (24V) coil and running low voltage control wiring anyway, it wouldn't be that much more expensive to run wiring with three conductors. You would need a set of momentary push buttons or switches, one normally open for the start circuit, the other normally closed for the stop circuit at each switch location or machine instead of a pull switch. The contactor would also need 3 pairs of contacts- two for powering the DC and one for the control "latching" circuit. This is essentially the same as a low voltage relay start switch used on older Delta machinery but without the over-current heaters. With the three wire system, however, you have full control from any location and can daisy-chain an unlimited number of stations. Here is a schematic of such a system which also includes a high dust alarm circuit wired into the "stop circuit" that turns off the DC when the dust bin is full.



I used button stations like this one mounted on my master control box. The complete cover, button, and switch assemblies were way too expensive from Delta and other sources, so I bought the button/covers on Ebay and mounted cheap momentary buttons from Radio Shack behind them.



I spent a lot of time thinking about the whole DC control issue a number of years ago, and came to the same conclusion as you about losing a wireless remote. However, I also realized that opening and closing blast gates was an even bigger pain! I know it is more than you want to do and you don't want to mess with pneumatics, but I went to a fully automatic system- when a machine is turned on and off, its blastgate opens and closes automatically. I have a circuit that detects when any gate is opened, anywhere, that starts the DC. I retained the three wire manual control of my DC but now mostly use it to turn the DC off. Here is a link to a rather long video of my entire system.

[Chris Parks]

Alan, yes mine is designed as you describe to switch without having to remember which switch last operated as they will all work independently, it would drive you mad otherwise. I had extensive experience with pneumatic industrial systems in years gone by and it would be a long day in hell before I went down that road. The only advantage I did see like you was using air cylinders I could operate the gates but I will suffer that one. I have all the stuff here to do the gates but I just think it is complicating stuff needlessly for my purposes. I might put reeds on them to trigger some alert LED's to show open or closed but that will be about all. I won't need a bin alarm as I am going to have one side in perspex, of which I have heaps, so I will be able to see what is happening there. Thanks for your interest and comments, it all helps especially for those who have yet to go down this road and the more ideas out there the better.

[Alan Schaffter]

Alan, yes mine is designed as you describe to switch without having to remember which switch last operated as they will all work independently, it would drive you mad otherwise. I had extensive experience with pneumatic industrial systems in years gone by and it would be a long day in hell before I went down that road. The only advantage I did see like you was using air cylinders I could operate the gates but I will suffer that one. I have all the stuff here to do the gates but I just think it is complicating stuff needlessly for my purposes. I might put reeds on them to trigger some alert LED's to show open or closed but that will be about all. I won't need a bin alarm as I am going to have one side in perspex, of which I have heaps, so I will be able to see what is happening there. Thanks for your interest and comments, it all helps especially for those who have yet to go down this road and the more ideas out there the better.

I tell you honestly, I was so lazy about my blast gates that I often ignored them when making a quick cut on the tablesaw or other machine, but it is such a pleasure not to worry about them now. I will admit, unless you have access to a source of inexpensive/surplus cylinders, pneumatic solenoids, and current switches (Ebay, etc. in the US) it can be very expensive. I just looked at some prices for new components tonight- wow! they are outrageous. My homemade gates were made with shop scraps then I converted them to autogates later with surplus parts. It would cost me 5 - 10 times as much per gate to automate them now with new components, and I have 12 gates! It is something you can do one at a time since they all work independently. Sounds like you have good reasons to avoid going this route, however.

You might want to think twice about a high dust alarm. I have a special need because my cyclone and dust bag (no bin, push-through cyclone), is not in the shop so I can't see it. You will really need to be conscientious about checking the dust level- one or two lapses that result in filling and having to do the nasty job of cleaning your filter, especially an expensive cartridge filter, will soon change your mind! Oneida just came out with a nice, reasonably priced unit. Mine is made with some inexpensive off-the-shelf parts, so is much cheaper and also turns the DC off.

[Chris Parks]

No filter, straight through the wall to atmosphere, it pays to live in a moderate climate where dust extraction is concerned. The cyclone is inside and the bin will always be visible. Mind you it remains to be seen if the perspex remains clear enough to see the level inside after a while as for sure it will become scratched and discoloured. It is all a learning curve and I like to experiment so the proof will be in the eating so to speak.

[Alan Schaffter]

No filter, straight through the wall to atmosphere, it pays to live in a moderate climate where dust extraction is concerned. The cyclone is inside and the bin will always be visible. Mind you it remains to be seen if the perspex remains clear enough to see the level inside after a while as for sure it will become scratched and discoloured. It is all a learning curve and I like to experiment so the proof will be in the eating so to speak.

No filter is the best setup, means better flow, and no worries about clogs.