Trouble Shooting

Powerfeed and Thread Cutting
   
1. Powerfeed does not move carriage  
    Cause                      
 Solution
• Carriage locked 
• Unlock carriage
• Speed selector not engaged
• Select speed I or II
• Leadscreq lever not engaged
 
• Move lever to the left
  or right
• Gears not meshing
  or teeth missing
 
• Check gears and adjust
   mesh
 
• Half-nut not fully engaged
  for threading
• Keep half-nut engaged
  for threading
   
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
  at proper time
• Check chart
 
   
Carriage and Milling Table
   
1. Powerfeed does't move table
 
     Cause      
Solution
• Carriage
• Unlock Carriage
• Gibs too tight
• Select Speed I or II
• Leadscrew lever
  not engaged
• Move lever to the left
  or right
• Gear not meshing or teeth missing
• Check and adjust gears
• Crossfeed not engaged
• Move crossfeed lever down
   
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
   
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 holding
  crossfeed nut
• Tighten screw
 
• Worn brass nut 
 
• Replace brass nut or adjust
  screw at end of nut
• Loose spanner nuts
• Adjust Spanner
• Loose Brass Nut
 
 
• Put shim between the
  stud on the nut of
  the hole
• Too much space between
  bearing and dial
• Add shim washers
 
   
Lathe Turning  
1. 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
   
2. 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
   
3. Machine vibrates  
    Cause     Solution
• Work mounted wrong
• Remount work
• Speed too high
• Reduce Speed
• Too much pressure at tailstock  
 
• Reduce pressure and
  increase lubrication
   
4. 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
   
5. 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
 
   
6. Too much backlash in the compound  
    Cause        Solution
• Loose spanner nuts  
• Worn Nut        
• Tighten spanner nuts
• Replace nut
   
7. 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
   
Milling
   
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
  moving
• 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
  tool
   
2. Depth of cut is not consistent  
    Cause          
Solution
• Quill moving   
• Lock quill
• Setup wrong  
 
• Make sure setup is parallel to
  table
   
Drilling
   
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
  belts
   
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
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  800-476-4849  |  170 Aprill Drive  |  Ann Arbor, Michigan 48103  |  USA