Lathe Operations Wiki
Hack Manhattan Has a Lathe!!
|The Lathe is|
Enco 9x20" Engine Lathe with inch and metric threading
Note: Although the lathe has been re-assembled and run, it's not quite open-seasons for general usage yet. What the procedure will be for checkouts, training, etc has still to be decided.
The lathe is not a workbench, vise, or shelf
The linear bearing surface of the ways is actually quite fragile and easily damaged (as you will see if you examine them closely) by denting or abrasion.
Do not set metal objects on the ways.
Cover the ways with the Ways Guard when installing or removing chuck or work items and when sanding/filing/grinding on the lathe.
Do not use the chuck as a vise for sawing or hammering
The lathe takes four lubricants (listed in frequency of use order):
* SAE 140 Gear Oil * Lithium General Purpose Grease * Graphite * Red "N" Tacky #2 Multi-Purpose EP Grease
SAE 140 Gear Oil needs to be applied in the apropriate locations each time the lathe is used. A list of those locations is located [here].
Lithium grease may be needed on the compound if it becoes dry.
The chucks should only be lubricated with graphite.
Motor Starting Checklist
No loose hair, clothing, jewelry (DO NOT FEED THE LATHE)
Belts set for an appropriate speed for workpiece/fixturing
Check power feed and threading half nuts disengaged (carriage moves freely with handwheel)
Work securely chucked without excessive overhang on either side of headstock
CHUCK KEY REMOVED
Rotate chuck through by hand and check for binding
SAFETY GOGGLES ON
Belt tensioner lever disengaged
Clean up chips with paintbrush/vacum
Apply a light coating or SAE 140 oil to the ways
If you are not going to be threading or using the power feed, drop the gear shift lever down to disengage the leadscrew
If you hear a lot of gear noise, check the meshing of the idler gears under the headstock gear cover with the small spur gear driving the gearbox. This can slip to the point where the teeth of the idler gear rub on the bushing.
Whenever using power feed or threading feed, keep a hand on the appropriate disengage lever, and full concentration on the work. Thinks happen quickly!
Two pins are used to unscrew the chuck. Place something between it and the ways so it doesn't drop off the spindle nose, or be prepared to catch it. If you plan to run in reverse there is a clamp that can be mounted on the back of the chuck to prevent unscrewing.
While there is a power carriage feed, it may be too coarse for good results. Using both hands in turn on the rim of the carriage wheel may aid in producing a constant rate feed and a quality finish.
Small 3 jaw self centering chuck
Large 4 jaw chuck (must use dial indicator to adjust to center)
Collect chuck with ER collets, range up to 5/8"
Micromark quick change toolpost with 3 holders for 1/4"-3/8" ?? bits/tools
Armstrong cutoff holder without blade or an armstrong post to mount it in
OEM toolpost with brazed carbide boring bar
Small carbide insert holder (5/16" shank?) with insert (type??)
Lathe milling attachment
Import drill chuck for tailstock (keyed jacobs style)
Steady and Follow rests
Note: at present we do not really have any normal HSS cutting bits or a way to grind them
The ER Collet
We haven't quite figured out how to fix the collet holder in the lathe spindle. If it were like the mill collets you would thread a long bolt into its back end but it didn't come with said bolt and a bolt would block up the pass throough hole. I saw on YouTube (so it must be true) that if you tap (gently - ask me how I know) on the front of the collet holder there will be enough friction in the Morse Taper to keep it from spinning. We don't have empirical evidence that this works, but it sounds like it might.
If you put the collet in the collet holder and then attach the collet nut the collet WILL get stuck in the collet holder. To properly use the ER Collet it should first be placed in the collet nut, which has an excentric ring at the front end. Next place the collet nut+collet on/in the collet holder and screw it loosely into place. Load the workpiece and tighten the collet nut. When it is tiime to remove the collet nut+collet the excentric ring in the collet nut will hold on to the groove just behind the front of the collet and extract the collet from the collet holder as you unscrew the nut.
ER collets come in 1mm increments and compress by 1mm so you can hold any diameter of stock by using the next largest size collet. Our set of collets is imperial 1/8", 3/16", 1/4", 5/16", 3/8", 1/2", 9/6", and 5/8" so will not cover all stock sizes.
Manual for Enco 9x20 lathe (PDF)
Introduction to 9x20 lathe operations (PDF) <--- Read This
Grinding cutting tools from HSS (high speed steel) blanks