J.J. Mcabe 4014

[theradioshop]

Below is the lathe as it sits in my shop. I need a bigger shop!
I am documenting all the work on the lathe in hand drawn diagrams, pictures, and video. Since this lathe is a bit scarce and over 100 years old, there is very little information on the web on these. I did find pictures of one similar to mine but had a few differences. J.J. McCabe went out of business in 1923.

I have not figured out the gear chart yet. Will have to study this a bit more, I guess.

I posted a few more pictures below and some of the accessories that came with it.

 

[theradioshop]

That key in the worm would have gib heads on both ends.

Valuable information thanks. I will see if I can find a drawing and duplicate that hey.

 

[benmychree]

As far as threading goes, stud gear is the one with the square nut, and the screw gear goes on the lead screw, The compound gears are two that are ganged together to mesh with the stud and screw gears for a double reduction, the middle gear is an idler, it just serves to connect the stud and screw gears, and plays no part in the overall ratio.

 

[benmychree]

Valuable information thanks. I will see if I can find a drawing and duplicate that hey.

It would be sort of U shaped with lugs on both ends to prevent it from sliding out, unless perhaps it could be straight with a round lug that fits into a hole in the ID of the worm.

 

[theradioshop]

As far as threading goes, stud gear is the one with the square nut, and the screw gear goes on the lead screw, The compound gears are two that are ganged together to mesh with the stud and screw gears for a double reduction, the middle gear is an idler, it just serves to connect the stud and screw gears, and plays no part in the overall ratio.

Thanks for that information. This helps a lot. Will be a while before we get to that point though but will file that knowledge.

It would be sort of U shaped with lugs on both ends to prevent it from sliding out, unless perhaps it could be straight with a round lug that fits into a hole in the ID of the worm.

I see. So here is my thinking so correct me if I am wrong. The carrier that worm gear sits in is fully enclosed on the ends and with just enough tolerance for the shaft to go though. I had to install the key in the gear, them sit the gear in the carrier. I had a 2 inch piece of shaft the same as the one on the lathe slid in to the assembly. This held the key stock in place. I then slid this over the main shaft and let it push the 2 inch stock out. I really do not see a way the key can come out unless it shears and the tow halves slide out. I was worried that the edges of the key stock would wear the casting of the carrier, so I rounded the ends of the key over.

 

[benmychree]

Thanks for that information. This helps a lot. Will be a while before we get to that point though but will file that knowledge.



I see. So here is my thinking so correct me if I am wrong. The carrier that worm gear sits in is fully enclosed on the ends and with just enough tolerance for the shaft to go though. I had to install the key in the gear, them sit the gear in the carrier. I had a 2 inch piece of shaft the same as the one on the lathe slid in to the assembly. This held the key stock in place. I then slid this over the main shaft and let it push the 2 inch stock out. I really do not see a way the key can come out unless it shears and the tow halves slide out. I was worried that the edges of the key stock would wear the casting of the carrier, so I rounded the ends of the key over.

Yes, I thought about that as a possibility also, it is entirely possible that the key did shear after being worn after a long use, yes, good idea to round the ends of the key only a little bit to prevent it from eating away the casting, I'd think they would have put hard washers at each end to prevent that from happening.

 

[theradioshop]

Great idea on the harden washers. When I tear it back down to start the restoration, I will visit that thought again. Will measure the inside of the carrier and length of the work and determine a tolerance for the washers.

 

[benmychree]

You would probably machine back the shoulders or shorten the worm to do that, I think.

 

[theradioshop]

Hi All,
Sorry for the lack of updates. Not much time for anything overthe last month.
Got quite a bit done on the old McCabe and will be posting some pictures as soon as I can.

Things that are finished:
Drive system
Head StockApron / carriage assembly
Chuck
Tail Stock.

I know this sounds a bit backwards but still have to strip the bead and legs, change gear assemblies.
But I wanted to get the lathe up and running and working correctly.
I found the chuck was "bell mouth" so had to grind the jaws in. Had over 20 thou run out.
It is now at about 4 thouh.

I attached a few pictures below.
One is the lathe in its current state. Sorry for all the mess but there is a lot of stuff in the shop. Once the lathe bed is cleaned and painted it will be moved to the wall and open up the shop a bit.

Now this is where I need some help and education.
This is on the change gear setup to get the feed right. I still do not understand it.
On the current setup it is cutting about 5 threads per inch. Needs to be slowed way down on the feed.

Nut (top gear) there is a 55 tooth
Idle gear is 104 tooth.
Screw is 60 tooth.

Current gears I have with the lathe are:
55
60
60
65
69
75
80
80
85
104 - This is the only gear I have that finds the idel shaft.

On some lathes I see there are mounted side by side. I really donr see that happening on this lathe.
On the Nut (top gear) it looks possible as there is a spacer so two gears could be fitted. The idle gearc does have a soacer but would put a second gear inside which would not align with any other gear.
The screw does not have a spacer but two nuts the lock together. Yep all greek to me as I am not used to this type of setup.
Other lathe has 5 gears in the setup and lathes I used in the past had quick change gear box.

I really think I am going to need some more gears.
Looking at the chart it is listed as Cut, Screw, Stud.
I guess Cut is threads per inch?

 

[benmychree]

Feeds would be accomplished with a belt on the step cone pulleys next to the change gears, not by the change gears.