On Tuesday, February 25, 2020 at 7:39:28 PM UTC-5, delvon daily wrote:
Mark wrote:

When you say big hole are you talking wall , cabinet , or other ?
When we redid our kitchen we wanted to change from over the stove / vent
to a cabinet model and what we found is to ask if there is a trim kit made.
We got a counter model and a trim kit to fit inside a cabinet
and it gives you a built in look. Trim kit was about $30 .

I can post pictures if you know of a quick picture posting site.

It's a wall above an oven where it has to match so I have to use the
existing trim kit which was for a larger microwave oven.

The bare opening is huge but it already has trim.

The bare opening of wood on three sides and oven on the bottom is
27 inches wide by 17 inches tall but that opening doesn't matter.

What matters is the black microwave fitting inside the existing trim kit
which is an opening of 22 inches wide by 13-1/2 inches tall.

I ended up with this Home Depot $100 microwave oven because of all the
stores I visited, it was the best fit but it's not tall enough either.

Magic Chef, 1.6cf, Model HMM1611B2, 1100W
21.8" wide, 12.8" tall, 19.2" deep.
https://www.homedepot.com/p/Magic-Ch...11B2/305708075

The four plastic legs were too short at 1/4" tall & 1/2" diameter.
The JennAir microwave legs are 15/16" tall & 1-1/16" diameter.

The old microwave four leg holes are 25/64" diameter each.
The new microwave four leg holes are 5/16" diameter each.
(I tested with drill bits where those are the ones that fit best.)

Much worse, the side to side distance of the old legs was 16 inches.
But unfortunately the side to side distance of the new legs is 15-11/16".

That's the biggest PITA so far since the feet fit on pre-designed rails
that are built into the wall out of formed sheet steel.

To fit that smaller leg to leg distance side to side (the depth doesn't
matter because of the rail that is built into the cabinet holds any
reasonable depth) I had to move & re-drill the steel supports bolted into
the wall and to the top of the oven underneath.

This is where I am stuck now.

I could not find new legs to fit so the closest Home Depot had was
something called Everbilt #141 178 "Threaded Felt Base Stem Glides" which
are meant for the bottom of wooden chair legs, I think. The 1" long
threaded stems fit into a 15/64" drill hole, which is too big for the new
microwave so I have to open up the new microwave to put nuts on the ends.
https://www.homedepot.com/p/Everbilt...4544/306229540

Strangely Home Depot did not have a round file that fit the mounting holes
in the existing steel inside mounting kit (the sheet steel runners for the
legs had to be moved from 16 inches to 15-11/16" inches apart) so I had to
drill them sideways to make the holes oblong (how is that normally done?).

The main thing left is I have to rip open the new microwave to mount the
Everbilt threaded felt base stem guides, unless I can find a source of 1"
long feet to put in the new microwave feet holes.

Have you looked at airflow/vents on the outside of the old vs new? Make sure that works, isn't blocked.