10k Reverse Tumbler On A 9in South Bend Lathe

[Mark_f]

I'm going to do the upgrade of putting the reverse tumbler from a 10k lathe on my South Bend 9 inch lathe. I have all the parts and read a couple write ups on the net about it, but I have a question. Has anyone here done this upgrade?

My question is.... After doing the conversion, the only thing holding the tumbler in place is the lever pin .... Is that all that is needed? The original has a bolt that holds the gear set in place that it can't come out of the headstock. It appears this conversion only relies on the lever pin for that.

Anyone have any information on this upgrade?

 

[wildo]

You've probably already seen this thread for reference, but in both of the photo sets posted there, the modification plate was bolted to the lathe.
http://www.practicalmachinist.com/v...adscrew-reverse-lever-installed-9-abc-129098/

 

[Mark_f]

yes, I saw the threads there. I will bolt the plate to the head stock using the original bolt hole, but I am referring to the tumbler itself. The original design is bolted to the head stock with the clamp bolt but in the conversion, there appears to be nothing holding the tumbler in the lathe except the pin for shift location. If you pull the pin to shift, it seems the whole tumbler assembly could slide out. I just wonder if I'm missing something. I will go at it slowly.

 

[wildo]

Ah, sorry- I misunderstood the plate for the tumbler. Gotchya.

 

[Mark_f]

I notice the tumbler has a "lock" ring on the end of it To keep it in the 10k head stock, But I don't know if that will be in the right place to work on the 9 inch head stock

 

[DoogieB]

For the 10k, I believe the tumbler is retained as you describe. I can verify on my machine tomorrow.

 

[brino]

Hi Mark,

Sorry I do NOT have a good, direct answer for you.....and I apologize in advance if I'm asking you more questions than you asked originally.

Your question made me go look much closer at my lathe.
I am currently running a Southbend 9A that does have tumbler reverse....however I thought it was factory.......so now I am confused.
Mine is catalog number 409R, 3-1/2 foot bed with serial number 94780, and a single lever quick-change gear box.
Based on that, I placed it as being manufactured around 1940'ish.

I say it looks "factory" because

1. the gear cover has a cut out for the handle
2. the tumbler lever has pins for stops at both ends, and
   
3. the detent holes are actually in the headstock, parallel to the lathe axis

Is your lathe even older, or did they have different options per model or year?

Regardless, maybe I can provide some useful info.......my tumbler reverse lever appears to have a "keeper" bolted to the headstock that goes in a arced groove in the tumbler arm.
A picture being worth 1000 words, it looks like this:


It is a little dark and dirty in there, but the two slot head bolts in the middle of the picture hold the retainer to the headstock.
The retainer rides in a groove in the arm.
The arm pivots around the long rod with the two gears and the hex nut on the end.

Does that help?

-brino

==================================================
The picture above was uploaded full size, but is not appearing very large.
Maybe this one added as a "thumbnail" will allow you to click it and zoom to see better.
....or you may need to save them locally and open them in a viewer.

 

[brino]

Mark, if it would help I could disassemble to get some pictures and measurements after work tonight. Let me know. -brino

 

[Mark_f]

Your tumbler is for an older lathe. That type with the "squeeze " handle is an old style used on older lathes . The tumbler I am using is from a 10k lathe and you pull the plunger to move the lever. To my knowledge, it was the 1960's when the factory started putting the 10k type lever on the 9a but I am not positive ( I remember reading that somewhere). Also , I don't remember the 9" using a single lever change box. Are you sure your lathe is a 9a?

I am going to check the old catalogs and see if I can find your lathe.

 

[Mark_f]

Brino,

I found your lathe in a 1930's catalog. It is factory. I don't know what year they changed. You would have to check the year of your lathe by the serial number, but it is much different than mine. mine is 1945 I think. I found a 9 inch that looks like yours in the 1934 catalog. I am guessing yours may be a little newer.


Edit: According to Steve Wells web site your serial number was made in 1939. and from what I see your tumbler is factory and up until at least 1940 it appears they did use the single lever change box.