Columbia Cylinder Machine Expert Needed - 2-4 Min Conversion

[Curt A]

I have a Columbia BF and recently purchased a 2-4 Min Conversion kit from a Columbia BE. Documentary info indicates that the 2-4 conversion fits both of these machines. The machines are basically identical, except for the length of the bedplates and feedscrews, so it seems that all the other parts may be interchangeable.

My real question is this: the conversion is basically a small gear cluster/transmission attached to the end of the feedscrew. I need to remove it from the shorter BE feedscrew and re-attach it to my BF feedscrew. The problem is that there does not appear to be any obvious way to remove it, even though it had to be attached by someone in the first place and literature seems to indicate that this could be installed by a dealer to upgrade a machine. Does anyone have any ideas???

[Curt A]

I think I have come up with a solution. My BF plays up to 6" cylinders (which are almost impossible to find), so if I use the existing feedscrew from the BE, which is shorter and plays 4 min cylinders, I can make it work by making an extension end cap/bearing for the BE feedtube, without changing either the original BF feedscrew or the BE conversion feedscrew. That way everything could be put back to original, if ever desired. What do you think of this idea?

[JerryVan]

Sounds like you idea could work. I would suggest that, if you do it, place the correct feed screw inside the BF cabinet so a future owner can convert it back if he/she so desires.

[Curt A]

After examining the 2-4 minute geartrain on the BE feedscrew, I discovered that the feedscrew itself is a custom item with an extension milled onto the gear end which is not on the standard feedscrew. The gear cluster is pinned to that extension and even if it could be removed, would not work on a standard feedscrew. With that knowledge in mind, the only feasible way to make this work on the longer bed BF is to mill an extension, like I thought at first, to extend the 2-4 min BE feedscrew to match the length of the standard BF feedscrew. This should not be a difficult undertaking - definitely much easier than making a custom length feedscrew...