On Fri, 13 Mar 2020 16:45:55 +1100, Xeno wrote:

What you also won't be able to check with those is bell mouthing of the
drum. In fact, the only part you *may* be able to measure is the
*unworn* lip, if any. Used to use dedicated drum calipers, designed for
the task.

Hi Xeno,

I appreciate greatly and agree with the "proper tools" advice from you and
Steve, where I must also note though, that I hadn't "noticed" a problem
with the general purpose tools in so much as you can get pretty deep with
general purpose mics, particularly if you use a larger mic than one inch
mic on rotors where the wear is pretty even in almost all cases I've seen.
http://www.bild.me/bild.php?file=9428041drum_brakes_3.jpg

Also, if you zoom into this photo I took long ago and look to the right,
you'll see that the "lip" is pretty much almost perfectly taken into
account by the stairstep shape of the inside jaws:
http://s1.bild.me/bilder/110417/9335528drum_brakes_2.jpg

Still, I don't disagree with your main point of view which is that special
purpose calipers and mics and dial gauges would be best for those of us who
do all our own automotive work at home.

The tools are usually free, except for their storage, where I get high
friction pads and shoes for a great price (around $25 to $50 or so an axle)
and rotors/drums for about the same price per wheel, where I've seen people
spend upwards of thousands of dollars for a four wheel brake job.

Given that I save hundreds, if not thousands of dollars by doing my own
brakes, it wouldn't be a bad idea to purchase brake-intended tools for
measuring runout, rotor thickness, and drum diameter.

Where do you purchase your brake-related measuring tools from?

Amazon "suggests" these for brake rotor inside diameter measurement:
o Fowler 72-010-777 Drum and Rotor Measuring Kit
https://www.amazon.com/Fowler-72-010-777-Drum-Rotor-Measuring/dp/B003Z344Y2/

o Brake Drum and Rotor Measuring Kit w/Caliper
https://www.amazon.com/Brake-Drum-Rotor-Measuring-Caliper/dp/B000XQ0YF2/

o iGaging 20" Brake Drum Caliper Gage Digital Electronic
https://www.amazon.com/iGaging-Brake-Caliper-Digital-Electronic/dp/B00HMJLOUW/

o K-D Tools 3774 Digital Brake Rotor Gauge
https://www.amazon.com/Tools-Digital-Brake-Rotor-Gauge/dp/B000RLLESE

o Central Tools 3M130 .300"-1.300" Brake Rotor Micrometer
https://www.amazon.com/Central-Tools-3M130-1-300-Micrometer/dp/B000P6UOJQ

And Amazon added this weird looking gauge for "resetting" brake drums:
o AMPRO T71558 Brake Drum Resetting Gauge
https://www.amazon.com/AMPRO-T71558-Brake-Resetting-Gauge/dp/B00A8FOEFE/

Note I don't even know how to use that last tool, as I've never seen one.
--
BTW, I love how well two simple long metric bolts work to loosen drums!
http://www.bild.me/bild.php?file=5687240drum_brakes_0.jpg