I just found out I've been reading the pyrometer wrong for a year

I was pouring a batch of 356 aluminum last Thursday, aiming for 1350 degrees. My foreman, Mike, walked by and asked why my furnace was set so high. I showed him the display reading 1350, and he just laughed. He pointed out I was looking at the Celsius scale on the old analog gauge, not Fahrenheit. I'd been overheating metal by about 500 degrees for months. No wonder my molds were burning out so fast. Has anyone else mixed up the scales on those old dual-readout pyrometers?

3 comments

3 Comments

garcia.miles2mo ago

Those old dual-scale gauges are a trap, man. I put a piece of red tape over the Celsius side after I did the same thing.

matthewbarnes2mo ago

My old pressure cooker had one, @garcia.miles, and I definitely added 15 psi by mistake once! That tape trick is a lifesaver.

jackson.wesley1mo ago

A buddy of mine borrowed his father in law's pressure cooker and did the exact same thing with the psi scale. He cranked it up to what he thought was medium pressure and ended up with a loud hissing mess all over the stove. Had to scrub burnt soup off the ceiling for hours after that. @garcia.miles, your tape trick would have saved him a whole lot of cleanup time. That dual scale design really is a trap waiting to catch someone off guard. Wish more people talked about this before we all learn the hard way with fifteen extra psi.