Chimney Cowl

[Onoff]

I need a couple of vented chimney cowls. Pot is 14" diameter. Any suggestions as to where, local roofing place ones are too small a diameter.

 

 

 

 

 

 

 

[Nickfromwales]

I'm shocked that you haven't 3D printed them!!??

[Onoff]

39 minutes ago, Nickfromwales said:

I'm shocked that you haven't 3D printed them!!??

 

The printer will only print 256x256x256mm. Don't think I haven't thought of it.

 

Mulling on printing 4, slip together quadrants that I could form cement over. 

[saveasteading]

3 hours ago, Onoff said:

Any suggestions

Are these working chimneys?

 

Why do you want cowls?   Rain and bird guards or spinning ones?

For the former, I googled and found 250mm easily,  

 I suspect you may need to reduce the diameter to suit the biggest you can readily find. It might look odd and not keep the rain out unless modified.

 

OR the non-mechanical ones look very simple and could be modified at hood and the legs, or fabricated even.

 

[Onoff]

Non working chimneys. Also considering making something like this:

 

[Onoff]

Thinking to fire up the plasma in the morning and cut a say 16" circle out of some thin stainless sheet I have here as a start. Maybe drag the torch round an old wheel rim. 

 

Thinking won't a flat plate be noisy in the rain?

 

Is a conical cowl necessary? I've no method either of rolling a downturn/lip on said disc.

[saveasteading]

I'd say that using steel 2mm or thicker won't be noisy. 

For a cone, cut a segment from a circle and reweld and that won't be noisy either.

Is a downturn going to help? Maybe just turning with pliers will do it in crinkly fashion.

[Onoff]

23 minutes ago, saveasteading said:

Maybe just turning with pliers will do it in crinkly fashion.

 

That's a good shout actually. I've a cable tray setter I made when at college, that might do it.

[saveasteading]

1mm thick stainless. Cut a radius line and lap the edges and rivet together for a cone. Then turn down the edges.

[Onoff]

Butt welded:

 

 

 

 

 

[Nickfromwales]

2 hours ago, Onoff said:

Butt welded

That's how @Pocster got parole.