SB 9" A Cabinet Underdrive

Hello all,
I'm a relative "newbie" who although not a machinist has been around machine tools and tool building all my life. Recently retired, I just aquired the subject lathe which I plan to use ultimately for building miniture steam and gas engines. I am about to begin cleaning the machine and looking for obvious problems etc., but I feel I need some help from this very knowledgeable group. Are there any not so obvious things I should be looking for etc? Are there things I should not do etc? The machine's cat # is CL3442 and the serial # is 47221NKR9. After cleaning etc. I know the Lathe needs to be leveled (I have borrowed a Starrett precision level)and aligned, but I really don't know where to begin. I live in La Crosse, WI. Any experts near by? I will be very grateful for any help I can get, on the web or in person. Thanks, Dave

SB lathes are very strait forward. Not a lot of springs or needle bearigs to swarm on you.

Be carefull with the spindle bearings. Dammage to the super finished surface is hard to deal with and heart breaking.

Ask questions if your not sure why something is not comeing appart as expected.

Take photos of stuff as it comes appart.

Dont bend the lead screw removing the carrage and apron.

Be very carefull when putting the apron back on the carrage, make sure the gears are in mesh befor tighening up the bolts.


Not an expert, but I will take at the final step.

Level is the starting point with any lathe.

Get the lathe where you want it to live, and cleaned up. Adjust the bearing play by removing shims in the headstock casting, clean and adjust the gibs, and get everyting otherwise in good order.

Then level the ways on the long axis.
Level accross the ways at the headstock, If two of the v ways are even, use them, otherwise set up some paralells on the flats of the ways.

Check the long axis for level again and repeat until everything looks cool.

Go get a beer.

Come back and move level to the rear of the lathe bed and check accross the ways.

Nope your not drunk yet, the ways are twisted.
Look down at little foot under the tail end of the ways. There should be two set screws, one in front and one in back. These twist the bed. Push it back to level and recheck everything.

Ok another beer is required at this point.
Rember, Level is the starting point.

Set a dial indicator in the chuck (power off) and swing it around your tail stock center (assumeing you have a center worthy of the task) If not by a dead center for this task or indicate the bore of the MT. Get the tail stock set side to side and shim up or down as needed. Shim the seperation gap in the tail stock. Also use the carrage to indicate the long axis of the tail stock quill to see if it droops. Be sure to note the droop in you indicator from gravity as you swing it without touching anything.

Small lathes line the SB 9 often have soft castings and show considerable ware, so dont expect the machine to be dead nuts perfect, no matter how hard you try.

Ok, now the tail stock is as good as you can get it.


Now chuck up on something soft and easy to cut, but big enough to be stiff. Say a 1" piece of brass with 4 inches hanging out of the chuck.

Take a test cut useing your power feeds and mike both ends. Only take about 0.020 off with a SHARP tool. This will tell you how worn the bed is.

Ok now center drill a long bar of something easy to cut, about 1.5" in diameter (again size is not that cricical) and as long as you can get between centers.

Clean it up with the first pass, take a finish cut and mike it in several places.

The bed may need a little twisting to compensate for ware and if you can turn between centers useing a face plate and dogs the reasult may be a little more accurate.

Thats how I go about tweeking one in.

Like I said, level is a basic referance, not gosipal. Make the lathe cut as true as is reasonable and see what happens.

a few other pointers Make sure there is no slack in the compound or cross feed and that the cuts are light. (locking the gibs on one or the other may be a good idea) Long parts should be expected to bow some, but with a light cut it should be undetectable.

use a cutter with a sharp point and small radius.

these SBs were intended for tool steel knives not carbide scrapers. Give it all the help you can, its not a very rigid set of ways or compound.

Have fun.

I'd say that ahall is entirely correct, particularly on the point of the machine being made for HSS tools and not carbide.

One thing that really hurts it here is the limited speed, and another would be the soft ways. Carbide tools require more pressure(or alternatively, create more pressure) to cut effectively, and will cause more wear on the machine. If using carbide inserts, stick to a small nose radius as this will require less pressure to cut.

If using brazed carbide, you should be able to use the same basic tool geometry as you would for HSS, but thats just IMHO.

I think your model number is actually CL344Z, where the Z indicates a 3 1/2 ft long bed. By the serial number is was made in 60 or 61. It probably cost around $650 when new. Look around the web and down load the parts manual, you can learn a lot by studying it. This is an undermoter drive bench mounted 9 inch, which is really the nicest one. Good luck! There is also a really nice South Bend Forum on Yahoo.