Southbend 9" Gearbox Conversion Part 3 - COMPLETE!

[@Dan.Whiteford]

That has indeed been most interesting to watch. Well done - and your photography is excellent as well!!

[@BruceBoschek]

Very interesting and informative video, as usual. Thanks for making the effort to share this with us.

[@martik778]

With the lead screw hand wheel, you can get a finish almost as good as power feeding and you don't need to engage the gears which is handy for quiet late night machining or when you need to hear the cut. You can also control the carriage travel by counting the revolutions.

[@hydrusavitus]

Oh, I see... Watched several of your other videos. Very nice work (both in terms of the work itself and the video/commentary). Looking forward to see more restorations or tool manufacture/upgrades ;)

[@schwartzenheimer1]

Really nice work. Thanks for taking the time to share it.

[@alexandermcgilton9204]

Just to share a tip for cutting to diameter, always machine a quarter inch on the end to final diameter before roughing. There are a few benefits in doing so, primarily should you go to far you can literally cut your losses. But also it's a great time saver as you don't have to repeatedly check diameter and finish cut then check. With the section done you can size up all roughing passes without measuring, and with the dial zeroed at the ideal diameter, compensating for error in tapper is simpel.

[@AlchemistLair]

Nice mod!! Thanks for all the detail in your video!!! I learned a lot that I can apply to my own lathe.

[@bobw7707]

Where did you get the nice gear change placard? I need a new one for my 1938 South bend 9". I really enjoy watching you rebuild the machines. Good job.

[@billyraibourn758]

Outstanding video H. I just picked up a South Bend yesterday, it is a 9" with a 3 1/2 bed and no gear box. I have never owned one myself and must learn to use it and found your videos in the process, so thanks for posting. Also can you point me in the direction to find out what year it was made so I can find a manual for it? Thanks H.

[@lindsaynicholls3110]

great work really love your stuff

[@kenzpenz]

This video was especially helpful for me as I am about to turn that shaft for the support assembly. I noticed your control switch mounted on the cover. Is that a South Bend switch ? I have a couple of Dayton switches that came with my lathe. I bought the switch holder on E Bay . The switch on my lathe was loose on the table. I think it had been mounted to the table previously. My Dayton switch comes close to fitting but will not simply bolt on. That is one complicated switch inside. I took several photos with the cover off just in case I had to change it. So, I will make a plate to attach the switch. Did I hear you correctly that you used a roll pin to connect the screw addition.

[@Halligan142]

The switch is made by Furnas specifically for Southbend. Labeled as a model 789. You can make a small adapter plate for the switch with the mount bolt pattern on one side and the switch bolt pattern on the other or you can go super easy and screw a piece of sheet metal to the mount and self tapper the switch in place. Yes there is a roll pin/spring pin that goes through the extension and the part of the lead screw that was supposed to fit into the support bearing. Figured it was better doing it this way rather than with loc-tite so I could easily separate them if I needed to.

[@Cleftwynd]

Nice job and well done!

[@jster1963]

Beautiful work! Thanks for the vid.....

[@OldManYoungMind]

Nice work. I really enjoy your videos. One thing makes me wonder about how you did this conversion, Did you lose movement of your carriage to the tail end of the lathe due to the lead screw adapter?

[@Halligan142]

Yes a little. The cross slide ends up stopping ~ 3 or so inches from touching the tailstock. I lose a little more if I want to engage the half nuts because they are mounted in the far right of the apron.

[@patdexter9188]

I've seen some video's of a guy installing a motor on the feed shaft towards rear of machine, isolating the feed shaft from the forward gears. With a reastat, instead of a gear box for thread cutting. What is your take on that?

[@Halligan142]

It can be done. The only problem would thread cutting and getting the feed timed to the headstock to be able to engage the cutter in the same place every time. Also there would be different feed rates depending on number of threads so that would have to be figured out also. The only way I can think of doing that would be by using a programmed controller and a Hall effect sensor for feedback to speed up and slow down a selected feed rate based upon spindle rpm.

[@hydrusavitus]

Nice work. I would polish and keep the old plate, though. I think restored it would look way better than the painted one.

[@johnbates9467]

Hey I tried the color and it looks great on my 1916 south bend 15"X6' lathe. Do you think something like this could be done with it like adding a gear now to it? When I got it it came without the change gears.

[@Halligan142]

+john bates I met someone who has a 30's era 15" with a single tumbler gearbox. Looks just like the one that's on a 16" and the lathe looks very similar to one, but I don't think a lathe of your vintage was designed for a gearbox. I could be wrong though. Your best bet is to go over to the practical machinist forums and ask in the SB lathe section.

[@jstephenallington8431]

I've just bought a 9a junior without the quick change gearbox. Can it be converted to a quick to a quick change too? I noticed that the apron on yours is different than the 9a junior that I have, but everything else *looks* the same as the lathe that you have.

[@Halligan142]

They are different. A junior has more in common with a heavy 10. The bed is wider than the 9" workshop series. It would have taken a single tumbler gearbox from an R series lathe which would be hard to find. You'd need a bunch of parts from that including the gear train, gearbox, apron, and leadscrew at the very least. Even then there is the possibility that the gearbox mounting holes will be different and cmay be clearance issues of the leadscrew against the feet castings.

[@jager9825]

I have a question. I'm converting my old 13" southbend from standard gear to quick change. Does it matter what gears I use to go from the spindle to the box via the banjo? It seems like it should be 1 to 1 ratio but I can't figure out how to do that.

[@gohuskies583]

I noticed you replaced the old leather belt with a modern rubber one. Did you have to pull the spindle out to install it or did you splice it somehow?

[@brianmilner5489]

wish I would have found these videos sooner. When I got my south bend lathe model c it came with a lead screw and apron for a long bend model A but no gearbox. I bought a model b lead screw off of eBay for cheep and now have the gearbox so I can convert it to a model A we could have swapped lol mine is a 3 1/2 bed.

[@rchopp]

Nicely done..

[@martik778]

Does "on the fly" mean while the motor is running? I shift gears with all settings within D and E, C doesn't always slip in easily

[@100nortonfan]

The lead-screw extension you installed visibly is out of alignment and will cause problems with the finish on turning. This is because as it whips around it will lift and lower the saddle when the half nuts are engaged.

[@Halligan142]

The leadscrew had some wear on it that allowed the extension to pivot on the pin a bit. it was bushed and fixed after this video.

[@ShuffleSk8Ter]

alright good job....I am sure it will be more fun now to thread or change feed speeds...IMO no lathe should be without

[@55nsmooth]

Did you ever drill the 3rd hole to support the gearbox? I'm going to do the same upgrade adding the QC gear box and wondering if the 2 screws are enough to support it long term.

[@Halligan142]

No issues with it so far

[@55nsmooth]

Thank you for answering! Your videos are well done and very helpful!

[@civedm]

Where did you gey that replacement plate?

[@Halligan142]

Ebay

[@MrWFCJR]

What tells you where to start each pass?

[@MukhtharAhmed]

Good tip, thanks

[@rickboh]

Nice Job

[@1230123012330]

good

[@worthdoss8043]

I guess by now you realize that isn't A 7 to cut 14 TPI it is A 8 .LOL. Nice gear box looks like new.