StanF South Bend 9A Rebuild Thread

[StanF]

The tailstock parts got some paint:



And some Perma Blue:

Then I stopped procrastinating and addressed the taper attachment:
Either the taper attachment was never moved or never used!

Mostly cleaned:

Fully cleaned and prepped for paint:

Painted:

And Perma Blue on all the hardware:

Tailstock assembly tomorrow...and then initial installation.
Also tomorrow, the taper attachment will get a 2nd coat of paint.

The Apron is the only thing left!

 

[neanderthal mach]

Mistakes can get missed by any businesses QC checks, but it's probably safe to assume your tail stocks Morse Taper would be concentric to the OD of the quill. Once your lathe is back to being operational, accurately mike that quills OD, then turn and face any piece of short scrap held in the lathe chuck to the exact same OD. Now move the tail stock up and extend the tail stocks quill to just touch the face of that turned diameter. Mike across the joining line for both diameters, the extra amount you see above your turned diameter will be very close to the exact number your tail stock is low. It won't be perfectly accurate due to unknown amounts of bed wear at the location the tail stock is locked down at. But it will be more than close enough to give you some ball park numbers that should be within a few thou.

Just for future information, your tail stocks bore would be it's main datum points and those can't be altered. To properly re-machine the tail stocks lower base and return that bore back to being parallel to the lathe bed, the tail stocks bore would have to be indicated square and true on a mill table in both X and Z. I'd want alignments before I started machining the base within at most a couple of 10ths of being dead true. And the same for the getting the base alignments correct before that re-machining starts. Holding it all square and rigid enough will be the main problem, and for sure take the most time for the set up.

And that wear is a good object lesson on the importance of wiping the lathe ways down and adding some way oil before moving your tail stock. Or even adding wipers to the tail stocks base. Yeah a general pita, but not doing so is the reason behind that wear. Most amateurs due to not enough knowledge (myself included) tend to either never oil often enough, and / or use the incorrect lube as well. The Connelly Machine Tool Rebuilding book I bought was enough to change my previous habits for good.

Fwiw and before I knew better, I once bought a new but absolute POS off shore 10" swing lathe. It instantly broke the tip off the first two center drills I tried using. After some checking with indicators, it turned out the tail stocks quill was pointing uphill about .009" in a 2" distance along it's extended quill. Add the drill chucks length and whatever amount that center drill was also extended outside the drill chuck, and the point on that center drill was at least .020"+ high.

 

[mattthemuppet]

It’s not too hard to add some ball oilers to oil the various sliding surfaces, then it becomes fairly straightforward to give everything a squirt of oil before use

 

[StanF]

(There's a Question of the Day at the very bottom of the post!)

Motor...yeah, I know that drum switch wiring has been covered a million times! At first glance, it looks like I'll need 7 wires run in the FMC conduit, including the safety ground.

The seven wires:
Red Out (for reversal)
Red In (for reversal)
Black Out (for reversal)
Black In (for reversal)
Neutral
Line
PE
That's a lot of wires to stuff through a 90 degree fitting into this little area .

As a side note, I'm using FMC instead of LT. The conduit fitting threads right into the motor body - you don't use a locknut. And the metal FMC fitting is much more secure. The plastic LT fitting that I tried felt like it was going to strip, so I gave up on that idea. I am going to put a locknut outside of the motor for use as a spacer, and to get the clocking correct on the fitting. You can kind of see the locknut in the picture above.

I found this nice diagram in another thread, which confirms the 7 conductors

Tailstock assembled, but not checked for alignment yet:


As it sits today:


Taper Attachment also mocked up for final assembly. It's just mocked up for now. I need to put it back together with some lubrication and adjust the gibs:



Question of the Day...it feels like it would be better to just leave the taper attachment off the lathe and in a drawer until it is needed.
Otherwise, parts would be moving continuously with the carriage and potentially wearing.
Correct?

 

[4GSR]

I'd leave the TA off until needed. Yes, it will wear down the rear shears badly. I had a 9" years ago that had the TA on the lathe and yeah it wore out the shears on the underside of the saddle badly from all of the weight of the TA. Just my opinion.

 

[DanAl]

I leave my taper attachment off. I had concerns about the weight on the saddle, as confirmed by 4GSR. As to wear on the taper attachment itself, there would be none as you would not need to mount the arm to the v-way.

 

[StanF]

Taper attachment properly lubed and assembled and relegated to a drawer:


Then I got started on the apron disassembly - the book made it pretty easy. I haven't started cleaning it up yet, but I didn't see any issues (other than a lot of dirt and chips!)

 

[M.B. Naegle]

With the motor wiring, a couple options would be to use flexible metal conduit as the ground and be sure you have solid metal to metal connections, which would get you down to 6 wires, or you can buy multi-wire cable like this at McMaster. They take up less space than having to run individual wires through a rigid or flexible conduit. Often these cables have wires that are all the same color, but they are numbered.

 

[4GSR]

Here's a similar wire for a bit less per foot and probably cheaper on shipping too.

New 18 AWG – Stranded 6 Conductor – 300V –High Performance Wire – $.50 per Foot | eBay

UL Rated TC 600V and PLTC 300V for cable tray applications. It can be installed in various types of conduit, ducts, raceways, and cable tray systems. It is also great for cold weather installations, being rated for both cold bend and cold impact resistance.

www.ebay.com

 

[4GSR]

I may have spoke too late here. I happen to be rumaging through my surplus wire I have on hand, guess what I found? Some seven conductor wire. It's about a 16ga. wire or 1.5mm sq. If interested let me know. I'll let you have 3 or 4 feet for free if you pay the postage.

 

[animal12]

If ya decide to just park the TA at least install the part that bolts on to the back of the saddle . It's a handy place to mount a indicator so it follows the work if needed . That's one of the few parts I have for a TA for my 9A .
animal

 

[jim rozen]

If you elect to use 240 volt power for the motor you can do it in fewer wires.

My preference for wiring like this is liquid-tite conduit. Not the inexpensive plastic kind, but it's metal spiral covered in plastic coating. The right angle fitting for the motor would have the same form factor as the one you are using now. I would suggest you avoid S- or SJ- cordage as they just don't hold up in the long run.

 

[4GSR]

................ I would suggest you avoid S- or SJ- cordage as they just don't hold up in the long run.

Really???

The original SJ cord that came with my 9" SBL lasted over 50 years. The only reason I replaced it, the wire was getting brittle and needed replaciing plus I changed it to a DC PM motor. Only three wires needed then.

 

[StanF]

Thanks for all the wiring comments. I've got some 1/2 FMC and a bunch of different colors of 16 awg wire, and I think I can make it work. I've just been procrastinating on the wiring this week.

I have been cleaning the apron parts:

I uncovered a minor flaw in the thread dial shaft...(there's a groove for the set screw...use it!) I may just remake this part later:

And there was a broken screw:

A center punch and a left-handed drill bit made for easy removal:

Then a little more cleaning...and the first coat of paint:

 

[jim rozen]

S, or SJ cordage will work. For a while. Does not hold up well to lube oil, cutting fluid, hot swarf. Liquid-tite conduit does, and you can put a lot of number 12 THHN conuctors in there.

 

[StanF]

The apron got assembled:

It all went together very easily:

There was one small hiccup - the wire clip was missing off the carriage shaft. I noticed it was missing when I disassembled it, but I had forgotten about it. (I believe it just keeps the adjacent gear in place on the shaft, as that gear has no other retention feature.)

I put an external snap ring on there, and it seemed to be adequate for the task.

Next, I'll get it installed and get everything lubricated. Hopefully some test cuts soon.

 

[StanF]

Apron is done except for testing:




Seven 16 gauge wires in 1/2 FMC:


This motor has many openings...I will seal them up somehow to prevent errant chips from getting into the motor. TEFC is definitely the way to go for a lathe motor, but I can make it work. .

The FMC has good clearance to the belt.

I watched the NBA playoffs instead of wiring the switch and installing the power cord:

 

[DanAl]

Beauty.

 

[4GSR]

Beauty.

Yeah, I'm jealous.
Now I want to fix up my 9" SBL like his.

 

[StanF]

Lathe is wired up, powered and working properly. The apron was tested and functions completely as expected. It runs reasonably quiet for its age. Videos or it didn't happen!

I have a few small things to do.

First, what's the best technique to bold up these letters? Foam brush? I'm worried about doing a poor job on these, so any tips?



Second, I am getting a pretty good oil leak on only one side of the QC gearbox. In the short term, I'm probably going to 3d print a little drip tray for that area.

Longer term, I may disassemble and check the oil control wicks. My concern isn't really with the oil dripping...it's that it is only on one side. It makes me think that the oil flow to the other side may be inadequate.

Third, the flat belt isn't tracking as well as I would like - it's riding on the edge, and not well-centered. So, I'm planning to adjust the drive unit to get better tracking. It's not bad, but could be better.