No. 4: Turning of Wheels on Carriage

Hello everyone~

Earlier this year I acquired a Vandercook No. 4 from my dear printing mentor. I recently discovered that the 2 front wheels on the bottom of my No. 4’s carriage have some inconsistent behavior, especially when compared to other No. 4’s.

Apologies as I’ve not been able to determine, from the manual, the proper name for these wheels (see photo for where my finger is pointing):

Here’s what I’ve observed on my No. 4:

• The 2 front wheels/rollers don’t turn as I move the carriage down the press bed with the press on Trip (even though the back ones do), but all 4 wheels do turn if the press is on Print.
• Whether the rollers are engaged or not doesn’t seem to matter.
• The front wheels never appear to be skidding on the metal (phew!), but if I place a sheet of text weight paper under them with the press in Trip, they will start rolling when I move the carriage.
• The wheels on the non-operator side are performing the same as on the operator side.
• Jules Faye, the previous owner of my No. 4 (serial #18759), took a look but wasn’t certain if these behaviors indicated that something was wrong. Looking through manuals did not provide any insight either.
• Video showing all of this: https://vimeo.com/111891529

Here’s what I’ve observed on other No. 4’s:

This behavior on my No. 4 (#18759) is different than what happens on the much older No. 4 (# 10017) that I teach with at the School of Visual Concepts in Seattle, which is what triggered my concern. (All 4 wheels that press turn, whether in Trip or Print).

To round out my research, I also contacted my pal Joseph Green — who miraculously just happens to own the No. 4 made right after mine (his is #18760) — to see if he observed the same behaviors on his press as on mine. He did not. Hmmmmm.

So, the core of my question to the group is:
Should all 4 wheels on the bottom of the No. 4’s carriage always turn when the carriage is moved down the press bed, or do certain wheels only engage at certain points — and under what conditions?

Bonus question: What are those wheels called? They don’t appear to be the “steady rollers”…

Many thanks,
Amy