Thread: pvc pipe size for ducting

Here are some pics. What I do is remove the cover, grind off the flange which appears after the cover is removed and screw it to whatever it is going on. I have used one on the blast gate I made in the first pic.

There is another flange that looks like this that will save you the need to grind anything away.
It's the one on the right in this image


If you can get it inside the cabinet so that it pokes through the cabinet to the outside then the radiused edge will act a bit like a bell mouth port and improve the air flow.

Bob I have never seen one like that, can you get it in 150mm and what is it called. It looks like it is two pieces glued together.

Originally Posted by Chris Parks

Bob I have never seen one like that, can you get it in 150mm and what is it called.

I don't know what they are called.
The 4" ones are available at most Bunnings.
The only place I have seen the 6" ones was at a specialist pipe shop but I don't have one myself.

It looks like it is two pieces glued together.

It's one piece, just that outer ring - I have pushed it onto a short piece of ducting.

You can make your own fittings if you prefer. Just heat about 30 mm of the end of a 150 mm pipe in cooking oil until it is quite soft. Then press it over a bell shape to get the shape started (I used one of my wife's baking pans) and then press it against something flat like a breadboard. Cool it with water, and there is your fitting.

Did this to make ports for several of my machines.

The only port made where the flange can be seen is post#3 at https://www.woodworkforums.com/f200/m...chines-161166/ The flange I made is in the 150 mm pipe pressed up against the band saw cabinet.

Apologies for taking so long to post these pics, I have been busy elsewhere.

Kev, Thanks for posting the pics.

Unfortunately the 90 mm ducting will really be throttling this system.
As I said in my post earlier in this thread a short 90 mm pipe will only draw ~345 CFM which is well below the possible spec for that DC.
One small benefit of using 90 mm ducting is that it is not a lot of money to lose when upgrading.

I note some of your ducting is above the gyprock? I assume you can get into the celling cavity to attend to any blockages?

Bob, I made sure that I could still gain access to the roof space just in case some blockage occurred

Originally Posted by Kev Y.

Bob, I made sure that I could still gain access to the roof space just in case some blockage occurred

or you can still eventually upgrade your system