Trouble Shooting

Powerfeed and Thread Cutting
1. Powerfeed does not move carriage  
• Carriage locked 
• Unlock carriage
• Speed selector not engaged
• Select speed I or II
• Sheared pin
• Replace pin
• Gears not meshing
  or teeth missing    
• Check gears and adjust
• Half-nut fully engaged 
• Keep half-nut engaged
2. Cut is not smooth        
    Cause      Solution
• Tool dull 
• Sharpen or replace tool
• Tool not on center
• Center tool
  (shim, if needed)   
• Tools not mounted tightly in post  
• Remount tools
• Cross-slide gibs to bed
  and base loose  
• Adjust gibs
• Gibs in toolpost loose    
• Adjust gibs in toolpost
• Tool turret not tight   
• Tighten toolpost
• Feed rate too fast 
• Install corrent gears
• Gear loose   
• Tighten gears and posts
3. Thread is not smooth  
    Cause     Solution
• Tool dull 
• Sharpen tool
• Tool not centered    
• Center tool
• Tools not mounted tight in post   
• Remount tool
• Cross-slide gibs to bed
  and base loose 
• Adjust gibs
• Gibs in compound loose   
• Adjust gibs
• Tool turret not tight       
• Tighten toolpost
• Gears loose   
• Tighten gears and posts
4. Tools is not cutting “on thread”  
    Cause      Solution
• half-nut fully engaged
• Keep half-nut engaged
• Clutch slipping  
• Tighten screws (6)
Carriage and Milling Table
1. Table won't move  
     Cause       Solution
• Table locks engaged
• Loosen locks
• Gibs too tight
• Loosen gibs
• half-nut not engaged
• Keep half-nut en
2. Horizontal and vertical movement
    in cross-slide table
    Cause           Solution
• Carriage gib improperly adjusted
• Adjust carriage gib
• Table gib improperly adjusted
• Adjust table gib
3. Vertical movement in
    cross-slide table
    Cause      Solution
• Carriage gib improperly adjusted
• Adjust carriage gib
• Table gib improperly adjusted
• Adjust table gib
4. Carriage moves smoothly in only
    one direction
    Cause       Solution
• Debris on way or gib   
• Remove debris
• Burr on gib   
• Remove burr with fine file
• Gib improperly tensioned     
• Loosen gib and re-tension
• One or more wipers mounted too low  
• Reposition wiper(s)
5. Cross-slide handwheel turns
    during cutting operations
    Cause         Solution
• Cross-slide brass nut worn 
• Tighten or replace brass nut
• Carriage lock not tight     
• Tighten carrriage locks
• Gibs too loose 
• Readjust gibs
6. Too much backlash in the cross-slide  
    Cause       Solution
• Loose screw   
• Tighten screw, review how to
  eliminate backlash
• Loose brass nut   
• Put a shim between the
  stud on the nut and the
  side of the hole
• Worn brass nut 
• Replace brass nut or adjust
  screw at end of nut
• Excessive space between bearing 
• Add shim washer and dial
Lathe Turning  
1. Clutch drops into nutral while turning  
    Cause Solution
• Too much gap between
   the jaw clutch and the
   left jaw clutch
• Shorten the shaft sleeve
2. Cut is rough  
    Cause Solution
• Tool dull
• Sharpen or replace tool
• Tool not ground properly    
• Regrind tool
• Tool at wrong angle
• Correct tool position
• Tools not held tightly
• Tighten toolholder
• Wrong cutter for material     
• Use correct cutter
• Cutting speed incorrect
• Increase or reduce speed
3. Work has unwanted taper  
    Cause     Solution
• Work improperly aligned 
• Realign centers on work
• Debris in spindle, setup, or tools
• Clean and reset setup,
  work, or  tool
• Offset tailstock incorrectly positioned
• Correct position  of tailstock
• Spindle bearings loose          
• Tighten taper bearings
   to return to alignment,
   replace spindle bearings
4. Machine vibrates  
    Cause     Solution
• Work mounted wrong
• Remount work
• Speed too high
• Reduce Speed
• Too much pressure at tailstock  
• Reduce pressure and
  increase lubrication
5. Work stops turning but machine
    continues to run
    Cause   Solution
• Work not mounted securely
• Remount work
• Tools forced into
  work/ excessive cut  
• Reduce force on tools
• Belts slipping
• Tension belts, use belt
  dressing, or replace belts
6. Diameter of work is not consistent  
    Cause            Solution
• Too much flex in workpiece  
• Use a follow rest
• Too much flex compound rest,
  cross slide, or carriage
• Tighten gibs, clean ways
7. Too much backlash in the compound  
    Cause        Solution
• Loose spanner nuts  
• Worn Nut        
• Tighten spanner nuts
• Replace nut
8. Machine slings oil from behind
    the chuck or in belt box
    Cause     Solution
• Oil reservior overfilled   
• Check oil lever
• Worn oil  seal     
• Replace felt in seal
1. Tool chatter  
    Cause   Solution
• Gibs too loose on cross
  slide, compound, or carriage
• Readjust gibs
• Unused feeds not locked  
• Lock all axes but the one
• Millhead not locked     
• Lock millhead
• Quill too loose   
• Tighten quill lock
• Tool not on center    
• Center tool
• Improper tool shape, tool dull  
• Reshape, sharpen, or replace
• Feed too light or slow  
• Adjust feed rate
2. Depth of cut is not consistent  
    Cause           Solution
• Quill moving   
• Lock quill
• Setup wrong  
• Make sure setup is parallel to
1. Hole is off center or bit wanders  
    Cause   Solution
• Bit dull      
• Use sharp bits
• Bit not mounted correctly in chuck
• Remount tool
• Bit bent
• Replace bit
• Chuck loose in spindle  
• Remount chuck on arbor
• Drawbar not secured
• Tighten drawbar
• Debris on spindle
• Clean debris and arbor
  and remount tool
• Bearing loose or worn  
• Tighten or replace bearings
• Cutting too fast   
• Reduce speeed
• Incorrect bit   
• Use correct bits
• No pilot hole    
• Drill small pilot hole
2. Entrance hole is out of round  
    Cause Solution
• Bit dull    
• Incorrect drill bit 
• Use sharp bit
• Use correct drill bit
3. Bit turns erratically or stops  
    Cause            Solution
• Bit fed into work too fast   
• Reduce feed rate
• Belts slipping 
• Reduce feed rate, re-tension
4. Chuck is difficult to tighten or loosen  
    Cause              Solution
• Chuck sticking 
• Apply lubricant
• Debris in chuck
• Clean chuck
5. Chuck wobbles  
    Cause Solution
• Chuck loose on arbor
• Clean arbor and remount
• Drawbar not tight    
• Clean spindle and replace drawbar
Drive System
1. Turn on the machine and
    nothing happens
    Cause Solution
• Machine unplugged
• Plug in machine
• Loose electrical connections
• Tighten wiring connections
2. Motor and pulleys turn,
    but not lathe or mill
    Cause  Solution
• Lathe mill clutch is in neutral
• Pull the clutch sleeve all
  out (lathe) or push it all the
  way in (mill)
3. Pulleys turn and clutch is
    engaged but the mill
    does not turn
    Cause  Solution
• T-key missing
• Replace key
• Bevel gears stripped or broken
• Replace bevel gear
• Bevel gear out of adjustment
• Readjust bevel gear
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  800-476-4849  |  170 Aprill Drive  |  Ann Arbor, Michigan 48103  |  USA