On Apr 6, 7:33 am, Sam Goldwasser wrote:
"larry moe 'n curly" writes:





wrote:

A couple of things come to mind, both of them pretty remote:

a) the batch of paint used had Titanium Dioxide as the white pigment.
It is just possible that the paint as-applied was more absorbtive than
the OEM paint & metal combination and so that area turned into a 'hot-
spot'. If they did an area say the size of a business card or more,
that would be the second thing that came to mind and that based only
on very careful prep... see b) below.

b) conversely and more likely, the prep-work took the microwave-
reflective primer off and exposed the steel. BAD MOVE as without that
reflective coating the metal will get very hot no matter what sort of
finish coating may be on top.

Does that apply only if there's a coating on top of the metal?
Because we have a microwave oven with a stainless steel interior

So how is stainless steel different than steel, microwave-wise? To reflect
microwaves implies a conductive material. The conductivity may be different,
but not dramatically.

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There are several patterns to how the magnetron works, and several
methods to spread the pattern over the food. "Better" ovens use a
combination of reflection and absorbtion to make the food cook evenly,
*in addition* to either a turntable or even the figure-8 pattern
turntables on some higher-end ovens. In these cases, the Turntable
platter and mechanism serves as the absorber, the vertical surfaces
will be the refectors.

In the cheaper fixed-position ovens where one is required to rotate
items or turn them over, the niceties of such designs are ignored and
the magnetron pretty much blasts in whatever pattern it is masked to
do. Scatter is to be absorbed by the surfaces of the oven.

There is a great deal of thought and design that is hidden in these
beasts. It is absolutely possible to put out an oven at US$39 that
will both cool and still make a profit for the retailer even after it
is shipped from China. It is also possible to spend $600 for an oven
that will not only cook but have all of these design niceties included
and still make a profit for the dealer even after it has been shipped
from China.

Point being that everything inside that oven, right down to the paint,
has been chosen for the purpose. And if they are stainelss steel
lined, that steel has also been 'designed' for the purpose. Can't go
by smell on the paint, can't go by looks on the steel.

Peter Wieck
Wyncote, PA