MartinHewitt wrote:My understanding is/was there are the Mosler 5-X locks, which are friction fence locks with 4 wheels, and there are Mosler 6-X locks, which are friction fence locks with 3 wheels, and the B-6 is wrongly labeled. But the probably wrongly labeled B-6 is not a friction fence lock, just like this Yale
https://keypicking.com/viewtopic.php?p=119660#p119660 . It is not visible in Squelchtone's catalogue if it is a friction fence lock or if it is spring loaded. The same is the case with the HPC manual. So were the 5-X and 6-X locks at one point changed from friction fence to spring loaded fence?
I'm going to revisit this, since it was never answered. And, I'm not saying I have the answer, but I think I figured it out. It would be nice if someone could confirm or deny the following.
I've seen No.5 with either three or four wheels (as shown in HPC). The changing instructions say the No.5 has three wheels. McOmie said that "most" No.5 have four wheels (meaning that some do not). It seems he is saying that in his experience he has seen more with four wheels, but some do have three, as confirmed in the changing instructions. The No. 5 is a friction fence lock, as seen in McComie's book.
The no.6, on the other hand, is shown in McOmie's book as having the spring-plunger bolt/fence (just like the one in the linked thread), and is described as having three wheels. As seen in the HPC manual, the curbs shown for the No.6 each have three wheels. The shorter hub on the model No.6 curb looks like it would only allow for three wheels, with no room for a curb of four.
At this point, I'm thinking the main difference between the No.5 and the No.6 is that the No.5 has a friction fence, and the No.6 has a spring-loaded plunger fence.
Also, note that the lock case for the No.5 is larger at 4.5" x 3.25", versus 4" x 3" for the No.6. I could be wrong, but I think some who think there were two different versions/sizes of the No.5 are actually comparing the No.5 and the No.6, not realizing the internal mechanism is different between the two.