[kapitan_krunch]

Purchased a home with a broken microwave, which I finally decided on replacing.
Turns out there's some really odd ducting happening and pretty sure the old "solution" didn't vent much at all.
There's an off-center 7 inch diameter pipe protruding about 3 inches out, situated only 5 inches above the microwave hood.

How would I go about connecting these? This is a really strange configuration, I'm thinking I have to shorten the pipe coming out to about 1 inch protrusion?
I don't have any sheet metal tools but not opposed to buying some small tools - just really kind of at a loss as far as how to make this connection

 

[Nealtw]

Need to have one made some thing like this with a cap on the top and round hole.

 

[kapitan_krunch]

Need to have one made some thing like this with a cap on the top and round hole.
View attachment 670671

Thanks! Where can I get this made? Is it expensive? Also I probably still need to cut the pipe to 1 inch or half an inch or so to get airflow

 

[Nealtw]

Thanks! Where can I get this made? Is it expensive? Also I probably still need to cut the pipe to 1 inch or half an inch or so to get airflow

If you do some digging you will find a shop that does sheet metal work. Some times a furnace installation company will have the equipment themselves.
You will want the face open so you can make the joint to the round pipe and seal that before closing .
The pros may have special tools for the amateurs we would cut in the one inch all the way around making tab.
After bending every other tab we fit the piece over the pipe and bend the rest of the tabs.
The same shop would sell you the sealer you would need to seal the joint.

You will need some exact measurements.
Perhaps a big piece of paper folded so it sits in place and you can mark out both holes.

 

[Domo]

You can see the old duct tape marks on the cabinet shelf and wall from the original "box."

Kinda looks as if a metal lunch box/ too box might do the job with DYI holes and tabs to accept a collar right adapter for the pipe... Oh, yeah, and good aluminum duct tape...

 

[Nealtw]

Cut the round hole in a big piece of craft paper and fold it at the shelf and mark out the rectangle and take that o a sheet metal shop and let them figure it out.