Logan quick change gearboxes

[phubbman]

I’d like to add a quick change gearbox to my Wards PowrKraft 2130 lathe. From what I’ve learned, one with a box that has ”1201“ or “LA 1201” cast on the inside of the bow will work With a little milling modification. What I don’t understand is why older gearboxes from 10” Logan lathes won’t work. As I understand it, the Logan 820 10” lathes came with both the earlier boxes and the later 1201 boxes. Why specifically won’t an older box work on my 2130 lathe?

I’ve seen that some people retrofit a South Bend gearbox onto their Logan, which requires a bit of work but is doable. What would need to be done to fit an older Logan box to my lathe?

I can’t find any specifics on this.

paulh

 

[Shiseiji]

Pushing the envelope on forum ediquite, this is from Scott Logan posted to the board he moderates on Groups.io:


From: "Scott S. Logan" <ssl@l****.com>
Date: Mon Oct 16, 2000 7:11 am
Subject: Adapting a QC Gearbox

Received the following private message from a subscriber, but I thought it
pertinent to answer here.

> Scott, Can a Wards (Logan) 2130 lathe be fitted with a quick
> change gearbox.

All Logan (and Wards) 10", 11" and 2900 Series 12" Lathes used the same
gearbox, after serial number 46561. The "Accessory Gearbox", as provided
for Wards Lathes or others not factory equipped, were the same as well,
with one minor modification.

Logan 10" and 11" Lathes not factory equipped with a QC Gearbox, also had a
"Plain Apron", meaning they did not have a clutch for power feeds. These
Lathes use a miter gear arrangement for power cross feeds, and rely on the
half nuts for power longitudinal feeds (in other words, power longitudinal
feeds are a very fine thread).

The aprons on such lathes are different in that the half nut is in a
different relative location.

On QC Lathes with the Automatic Apron, the Lead Screw is on the same
vertical plane as the front edge of the bed. In other words, a vertical
line drawn down from the front edge of the bed would intersect the
centerline of the Lead Screw.

On Plain Change Lathes with the Plain Apron, the Lead Screw is ~11/32"
closer to the bed wall.

As a result, when moving a QC Gearbox from a Lathe with the Automatic Apron
to one with the Plain Apron, the mounting surface of the Gearbox must be
milled down ~11/32". The tailstock support bearing would not be changed
from the original on the Plain Change Lathe. Of course, the Lead Screw
will need to be either kept with the Gearbox, or shortened up to
accommodate the Gearbox.

Please note that Gearboxes from earlier lathes, prior to 46561, or from
2500 Series 12" Lathes, or from any 14" Logan Lathe will not be adaptable
to the 10" or 11" Plain Change Lathes. Also, the Gearbox from the 9"
Lathes are different, although the internal parts are mostly the same (the
Drive Shaft is different, as well as the box itself).
Hope this helps. If not, suggest you simply ask Scott on his board.

Ron

 

[phubbman]

Yes, I’ve read that. But it left me wondering why the older gearboxes won’t work. I am curious about that.

 

[Shiseiji]

Yes, I’ve read that. But it left me wondering why the older gearboxes won’t work. I am curious about that.

So your specific question is why gearboxes from earlier lathes, prior to 46561 won't work. Joining a forum is a pretty easy way to ask the man who made the statement. I've communicated with him through the board, including a couple of major foot in mouth, and he's always come across as a rather reasonable person. Worst that can happen is he won't know or won't answer. If you do FaceBook you could search that forum and see what's been posted.

Ron

 

[phubbman]

well, for me it’s now a moot point. I found an LA 1201 gearbox and will put that on my lathe. Still curious however.
Paul

 

[phubbman]

Ok, got it cleaned up, milled, and mounted. The biggest point of hesitation was cutting down the lead screw - I measured it at least 3 times. Along with new paint, I refreshed the brass plate by giving it some new black paint, then carefully exposing the raised brass lettering with some 600 grit wet/dry paper. It works great. I think I’ll like the convenience, and I know I’ll appreciate the slower carriage feed rate (2.5 times slower than what the standard change gear setup will allow).

 

[RalphF]

Paul, I might have the answer for why some model gear boxes don't easily attach. I have the same Wards lathe as in your picture, and came across a QC on ebay some time ago. Little did I know to look for serial numbers that match the gearbox as Scott Logan pointed out in his email. Turns out that in the my picture, A = 1.75" diameter, and interferes with the radius in the plate C. Also, the stub B is cast into the housing, so the plate was not used in the original lathe the gearbox came from, or so I guess. Without being able to use the plate, I will not be able to close the gear cover. At the present time, I did not come up with a workable solution. - Ralph

 

[phubbman]

Thanks for the info Ralph. Makes good sense

 

[Shiseiji]

Ralph, great first hand information! Very nice for your first post.

 

[RalphF]

Paul, I wanted to ask you, did you have to make a fixture to guide drilling holes into the bed of the lathe for mounting the QC gearbox? - Ralph