Trouble Shooting

Powerfeed and Thread Cutting
   
1. Powerfeed does not move carriage  
    Problem                      
 Solution
• Carriage locked 
• Unlock carriage
• Speed selector not engaged    
 
• Select speed I or II or III,
  engage drive selector
• Sheared pin
• Replace pin
• Gears not meshing
  or teeth missing    
• Check gears and adjust
 
• Inch/metric lever in neutral   
• Engage fully
   
2. Cut is not smooth        
     Problem     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 
• Choose correct setting
• Gear loose   
• Tighten gears and posts
   
3. Thread is not smooth  
     Problem     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”  
     Problem     Solution
• Powerfeed slipping
• Engage halfnut fully
• Clutch slipping  
• Tighten screws (6)
   
Carriage/Milling Table
   
1. Table won't move  
      Problem       Solution
• Table locks engaged
• Loosen locks
• Gibs too tight 
• Loosen gibs
   
2. Horizontal and vertical movement
    in cross-slide table
 
     Problem          
Solution
• Carriage gib improperly adjusted
• Adjust carriage gib
• Table gib improperly adjusted
• Adjust table gib
   
3. Carriage moves smoothly in only
    one direction
 
     Problem      
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)
   
4. Cross slide handwheel turns
    during cutting operations
 
     Problem         Solution
• Cross-slide brass nut worn 
• Tighten or replace brass nut
• Carriage lock not tight     
• Tighten carrriage locks
• Gibs too loose 
• Readjust gibs
   
5. Too much backlash in the cross-slide  
     Problem     
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  
     Problem     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  
     Problem     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  
     Problem     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
 
     Problem   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  
     Problem            Solution
• Too much flex in workpiece  
 
• Use a follow rest,
  use tailstock center   
• Too much flex compound rest,
  cross slide, or carriage
• Tighten gibs, clean ways
 
   
6. Too much backlash in the compound  
     Problem        Solution
• Loose spanner nuts  
• Worn Nut        
• Tighten spanner nuts
• Replace nut
   
7. Machine slings oil from behind
    the chuck or in belt box
 
    Problem    
Solution
• Oil reservior overfilled   
• Check oil lever
• Worn oil  seal     
• Replace felt in seal
   
Milling
   
1. Tool chatter  
     Problem   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
• Feed too light or slow  
• Adjust feed rate
   
2. Depth of cut is not consistent  
     Problem           Solution
• Quill moving   
• Lock quill
• Setup wrong  
 
• Make sure setup is parallel to
  table
   
Drilling
   
1. Hole is off center or bit wanders  
     Problem   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  
     Problem Solution
• Bit dull    
• Incorrect drill bit 
• Use sharp bit
• Use correct drill bit
   
3. Bit turns erratically or stops  
     Problem            Solution
• Bit fed into work too fast   
• Reduce feed rate
• Belts slipping 
 
• Reduce feed rate, retension
  belts
   
4. Chuck is difficult to tighten or loosen  
    Problem             Solution
• Chuck sticking 
• Apply lubricant
• Debris in chuck
• Clean chuck
   
5. Chuck wobbles  
    Problem 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
 
     Problem Solution
• Breaker Blown   
• Reset circuit breaker
• Machine unplugged  
• Plug in the machine
• Loose electrical connections
• Tighten wiring connections
• Electrical components bad 
• Replace defective parts
   
2. Motor and pulleys turn,
    but not lathe or mill
 
     Problem  Solution
• Mill or lathe not selected
• Select proper function
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