On Dec 9, 2:14 pm, beecrofter wrote:
Peel the cover from a junk water heater, ...

The one I turned into a firewood loading chute mikes 0.020". It's
painted outside and bare metal inside. It was easy to work with; I cut
it with hand snips and bent it over a plank with a rubber hammer. It's
flimsy and may not contain flying objects. Are you just covering the
vent holes in an open motor?

Jim Wilkins