Just setting up an extraction system in my new workshop with the AP50E and looking at ducting. I have a couple of fixed tools, mitre saw with hood and a benchtop belt sander, that can have solid hose, but also want a flexible hose in the system for moving around different areas.
The PVC stuff on axminster is quite expensive and mostly out of stock for the lengths I want. I was looking at cheaper alternatives and wondered if you can use that thin PVC ducting.
I use a heavy duty hose from the extractor to my table saw as the hose lays on the ground. For the mitre saw and planner I use Axminster Clear Lightweight PVC hose. What ever type of hose you use, make sure it has wire reinforcement of some sort. For the straight runs I used some Screwfix 100mm ducting. It is lightweight but strong enough to hold it’s shape and is a fraction of the cost of anyone’s rigid ducting. For the long run of solid ducting I installed some braided wire wrapped along the length of the duct and grounded both ends to the case of the extractor and mitre saw. Some people say this is not necessary but I disagree.
In my view the ducting needs to be conductive to stop the build up of static electricity on the inside of the pipe. The build up of static electricity can either cause blockages or worst case a spark can start a fire inside the duct.
To avoid the build up of static electricity the pipe either needs to be metal or conductive plastic which is normally achieved by adding large quantities of carbon black to the plastic before extrusion of the pipe. The pipework then needs to be earthed using appropriate clamps & earth wires.
The ducting does not necessarily need to have any conductive materials added. The flow of sawdust or wood chips rubbing along the plastic pipe will generate static electricity. Take a balloon for example. It is basically plastic. Rub it on a piece of carpet and the balloon will take on a static charge.
My braided wire wrapped around the duct is attached to the duct in four places with small screws, then grounded through the case of the extractor and mitre saw. After heavy use I have never had any sort of electrical “shock” when touching either machine.
Hello,
When I was setting up my dust extraction in my workshop I used a company called TLC Direct. Look in the ventilation section for 4” pipe and fittings. I found this to be excellent. I have had no static build up. For the final sections to the individual machines I used the flexible hose from Axminster or sometimes Rutlands who on occasions can be a bit cheaper.
Hope this can help you.
Mike.
