lathe training

Basic Lathe Operation

Maintenance Department

Safety

• Follow all instructions in the machine manual.• Wear approved industrial safety glasses & safety

shoes.• Do not wear gloves, long hair, long sleeves, rings,

jewelry or other loose items that could become caught in moving parts.

• Keep all parts of body away from moving parts.• Use proper point of operation safeguarding.

Main parts of the lathe

• Headstock• Carriage• Bed• Apron• Tailstock• Chuck• Cross slide• Compound rest• Controls

Four jaw chuck

Three jaw chuck

bed apron

carriage

tailstock

steadyrest

Quick change tool post

Cut off tool

Knurling tool

Quill

Drill chuck

ourouo

Our lathe

Control system of the Lathe• Lever for cutting right or left hand threads.• Spindle speed - change handle.• Coolant pump motor switch.• Spindle speed - change handle.• High-low switch for main drive motor• Upper slide tightening screw.• Handle for moving cross slide.• Handle for locking tool post.• Handle for moving upper slide.carriage.

Control system of the Lathe• Lever for changing thread pitch or feed rate.• Main switch.• Control lever for changing thread pitch on feed rate.• Lever for the rotating direction of spindle.• Handwheel for controlling the travel of the carriage.• Handle for controlling the half nut to effect transverse or

longitudinal feed movement.• Lever for the rotating direction of the spindle.• Handle for changing speed.

Control system of the Lathe• Screw for positioning carriage slide.• Handle for locking tailstock quill.• Nut for positioning tailstock.• Screws for cross adjustment of tailstock.• Handle for quick release of tailstock.• Handle for moving quill.

Feed & thread change handles

Spindle speed handles

Feed direction handle

Feed engage handle

Various operations performed on the lathe

• Turn

• part

• face

• neck

• radius

• bevel

• bore

• drill

• thread

• tap

• knurl

• taper

Cutting tools used on the lathe

• Right hand & left hand

• roughing tool• turning tool• facing tool• threading• bevel• radius• knurling• necking & cutoff tool

Cutting edge termsSide rake angle

Back rake angle

Side clearance angle

End clearance angle

Side cutting edge

End cutting edge angle

Cutting speeds for high speed tooling

• Aluminum 600 - 2000 feet per min

• brass 500 - 1000 feet per min

• cast iron 50 - 60 feet per min

• steel [crs] 100 -180 feet per min

• steel [medium] 80 -120 feet per min

• steel [tool] 30 -50 feet per min

Cutting speeds for carbide insert

• Steel 390 - 660 feet per min

• stainless 260 - 480 feet per min

• tips

• use coolant

• if chips are blue ,the speed is too high.

Cutting speed formula

• Rpm = 4 x cs

dia.

Turning a part in lathe

• Roughing cut : tool a little above center & more feed.

• Finishing cut : good edge on tool & less feed.

• Filing : file to final size at high speed.

• For safety reasons, file with your left hand.

• Polishing : with emery for best finish.

Parting in lathe

• Tool should stick out a shade longer than half the dia. of the shaft.

• Part as close to chuck as possible.

• Tool should be right on center.

• If too high, tool will ride on small dia.

• If too low, it will dig in & grab.

• Use plenty of lubricant

• Feed by hand & be sensitive

KNURLING• KNURLING TOOL IN THE CENTER OF

SHAFT.

• TOOLS SHOULD BE PARALLELTO SHAFT.

• SET LATHE AT SLOW SPEED.

• MEDIUM OR FAIRLY COURSE FEED.

• MOVE TOOL IN AT RIGHT EDGE ABOUT .015 OF INCH TO START DIAMOND.

Knurl Types

THREADING• TURN SHAFT TO PROPER DIA.

• SET DIALS TO THREAD TO BE CUT.

• SET COMPOUND REST TO 29 DEGREES.

• TOOL SHOULD BE ON CENTER & CUTTING EDGE SET WITH A CENTER GAGE.

• SLOW SPEED.

• BRING TOOL POINT IN & TOUCH SHAFT.

THREADING

• SET CROSS-FEED COLLAR & COMPOUND COLLAR TO ZERO.

• THEN CLEAR THE WORK TO RIGHT.

• THE CROSS-FEED SHOULD BE BROUGHT BACK TO THIS ZERO AFTER EACH CUT.

• MOVE COMPOUND IN A FEW THOUSANDS & ENGAGE LEAD SCREW.

THREADING

• THE LEAD SCREW SHOULD BE ENGAGED ON THE SAME LINE EVERYTIME TO MAKE IT SIMPLE.

• IT IS BEST TO PICK A NUMBER & USE THE SAME NUMBER.

• AFTER FIRST CUT, CHECK TO SEE IF THE RIGHT PITCH IS BEING CUT.

• USE CUTTING OIL WHILE CUTTING.

THREADING

• FORMULA FOR THREADS.

• THREADS PER INCH DIVIDED BY .750

• THIS WILL BE THE TOTAL NUMBER OF THOUSANDS TO MOVE THE TOOL INTO THE WORK.

• A NUT SHOULD BE USED FOR FINAL FIT.

Chasing dial

CLEANING

• ALWAYS CLEAN LATHE AFTER EACH USE.

• IT IS BEST TO USE A BRUSH TO CLEAN OFF CHIPS.

• AIR CAN BE USED WITH CARE & GLASSES ON.