Daniel Blake has a set of axle housings in the classified section. One has a flat spot. I’m guessing this was caused breaking an axle shaft, grinding to a halt and the dragging the car to where it was repaired? My question is, how far would the car have to be drug on a dirt road to grind off that much iron? And did people just not care back in the day?

Without seeing a photo, the drums to backing plate are not sealed in any way so depending on how severe the ground off spot is, should not be a big deal. The rear brakes are for parking anyway and were meant only to hold the car when stopped. If you think about outside brakes are exposed to a lot more dirt and water.

http://www.mtfca.com/discus/messages/3487/914769.html?1542297607

Must have been a common problem. I have three housings with flat spots like that. I had to eventually use one on a rebuild and have had no problems. With the drum on you have to crawl on the ground to see it.

I’ve got one too... is that weldable to build it up?

those are ductile iron, you can build up with brase. charley

How far? 100 feet if the road is coarse. Could be further if it was downhill.

Character mark, not worth the effort to do anything about it, "if it isn't broke don't fix it".

Had a flat or axle issue way back when and the car was drug home or moved somehow. Fairly common to see this. Doesn't really hurt anything. Unless your a purist you may want a better one.
As L Butler says it's a character mark.

A common problem. How easily weldable varies some with specific vintage and manufacturer. However, I have welded and/or brazed several of them myself (and I am not the best welder around here!). Back in the day, that much ground off was considered a minor issue and usually put back in use with only replacement of the axle if needed. These also got ground off if a wheel simply fell off due to lack of a cotter pin or loose nut.
I am not sure how easily welded these early backing plates are. I did do some welding and brazing on a '13 that went smoothly. Years ago, I welded a Ruckstell's backing plate, and it was a cakewalk. On the other hand. A couple years ago, I attempted to repair an early Ruckstell (had Hall-Scott cast into the backing plate, not a Ford issued one) that someone else had tried to weld years before. They had done badly, with terrible results. I am pretty sure I could have done fine if I had done it from the start. But working around their bad welding and the added cracks and flaws they had caused? All I did was make it worse. So I replaced the original Hall-Scott with a Ford issued backing plate. I still have the badly damaged Hall-Scott end and do think I could still fix it if I need or want it.

I do't know exactly how the earliest ones were mad, what type of iron was used. But the '12s like he has for sale should be like the '13 I repaired a few years ago. Probably a simple case of making a steel piece to replace the missing material, and brazing into place. Personally, I would braze that. Others will disagree. But unknown material compatibility issues could result in the weld trying to mix materials that will not mix. That is not a stress or structural point. And brazing would avoid compatibility problems (that is my opinion). A hand held angle grinder then can blend the contours. If done well, once painted, it will not be noticeable.

In one of his pictures I see a block off plate over the opening for the drive shaft so my guess is that this axle was used as a wagon or trailer and could have lost the wheel and been pulled for miles to grind it off. Also he says one side is welded around the rivets so it might have been over loaded to. Hard to tell what it has been through in the last 106 years.

Please, l didn’t mean anything derogatory about the housings. I’ve seen a number of these over the years and just curious.

If it was late September,early October way back in the day and it was under a trailer with a load of corn or other grain headed for the crib or grainery,the harvest still has to be brought in even if a wheel falls off. Depends on how far they have to go of course and whether it's a team or tractor pulling it. There's all winter to fix it once everything is in.