Laurentian
Stainless
- Joined
- Mar 2, 2008
- Location
- Canada
A little background :
-Former Northern Electric ( Nortel ) Ottawa R&D dept. machine
1967 low to medium hours, great shape
-We installed 2010 and all oils-grease-coolants were changed
-Machine ran an average of 2 full days a week at first and now almost daily 8-10 hours shifts, religiously oiled every morning at start up.
-Staff is careful with feed speed changes machine off and making sure plunger is set with lower dial at 6 o'clock on both handles.
Earlier this week my apprentice was running the mill with Z power feed upwards and heard a momentary gear grinding noise. Happened twice so second time he went and got my senior machinist that has extensive experience on it and had him check everything over. Nothing unusual and all dials were well set.
Then maybe a half hour later we heard this loud horrible heart wrenching gearbox grinding noise that jolted me upright and raised my pulse. Apprentice shut off power feed and hit emergency stop within 3 to 4 seconds, quick thinking !
Went back there with visions of machine apart for months on end sourcing parts and having to purchase another one at now inflated prices with unfavourable US/ Can exchange rates..
-Checked dials, all set as should be.
-Manually spun back handle all ok
-Hit start-stop same horrible crunching sound from centre or base of machine
-Took machine out of preset feed and dialed in another. Seemed a little notchy until I spun a complete revolution or two going through all the feeds. Did same with spindle speed, nothing unusual there.
-Calmed down a bit, triple checked everything, asked my guys a few questions, nothing out of place except a feed change earlier from one setting directly to the next without going though a full revolution to exercise machine like I like to do.
( at this point I'm suspecting sloppiness - backlash in the feed dial mechanism )
-Came over here to read up.
-Gearbox oil levels standing still : feedbox upper window mark ( clear ) and speed box half window ( slightly dirty tan colour ) Last changed in 2011.. ( kicking myself for not changing sooner, work for that mill crept up on us and now were're already in 2019..)
-drained both looking for gear teeth or metal shavings, nothing.
-filled with clean diesel fuel and drained both looking for gear teeth or metal shavings, nothing.
-filled with clean left over pantograph light spindle oil and drained both looking for gear teeth or metal shavings, nothing.
-filled to upper window limit with Shell Tellus 46
-hit start-stop all good and oil movement from slinging oil, level dips down to halfway mark on upper, upper 2/3 mark on lower. Upper oil still has a little tan colour maybe just the window but will change out again later.
cleaned, oiled, greased, double checked everything machine runs great and seems a little quieter.
-let it run for an hour or so as I put everything away and cleaned up after myself. No heat, all good. Multiple feed / speed changes all good as new.
This points to either a bearing going out, the rapid feed mechanism acting up but most likely slipping out of gear due to a feed-speed selector dial issue.
I'm confident in running the machine as is until I can get the operators side panel off and clean - inspect the dials and look into the gearbox directly. I did run a mini camera into the oil fill and drain holes and the teeth appeared normal for a 50 yo machine.
-Former Northern Electric ( Nortel ) Ottawa R&D dept. machine
1967 low to medium hours, great shape
-We installed 2010 and all oils-grease-coolants were changed
-Machine ran an average of 2 full days a week at first and now almost daily 8-10 hours shifts, religiously oiled every morning at start up.
-Staff is careful with feed speed changes machine off and making sure plunger is set with lower dial at 6 o'clock on both handles.
Earlier this week my apprentice was running the mill with Z power feed upwards and heard a momentary gear grinding noise. Happened twice so second time he went and got my senior machinist that has extensive experience on it and had him check everything over. Nothing unusual and all dials were well set.
Then maybe a half hour later we heard this loud horrible heart wrenching gearbox grinding noise that jolted me upright and raised my pulse. Apprentice shut off power feed and hit emergency stop within 3 to 4 seconds, quick thinking !
Went back there with visions of machine apart for months on end sourcing parts and having to purchase another one at now inflated prices with unfavourable US/ Can exchange rates..
-Checked dials, all set as should be.
-Manually spun back handle all ok
-Hit start-stop same horrible crunching sound from centre or base of machine
-Took machine out of preset feed and dialed in another. Seemed a little notchy until I spun a complete revolution or two going through all the feeds. Did same with spindle speed, nothing unusual there.
-Calmed down a bit, triple checked everything, asked my guys a few questions, nothing out of place except a feed change earlier from one setting directly to the next without going though a full revolution to exercise machine like I like to do.
( at this point I'm suspecting sloppiness - backlash in the feed dial mechanism )
-Came over here to read up.
-Gearbox oil levels standing still : feedbox upper window mark ( clear ) and speed box half window ( slightly dirty tan colour ) Last changed in 2011.. ( kicking myself for not changing sooner, work for that mill crept up on us and now were're already in 2019..)
-drained both looking for gear teeth or metal shavings, nothing.
-filled with clean diesel fuel and drained both looking for gear teeth or metal shavings, nothing.
-filled with clean left over pantograph light spindle oil and drained both looking for gear teeth or metal shavings, nothing.
-filled to upper window limit with Shell Tellus 46
-hit start-stop all good and oil movement from slinging oil, level dips down to halfway mark on upper, upper 2/3 mark on lower. Upper oil still has a little tan colour maybe just the window but will change out again later.
cleaned, oiled, greased, double checked everything machine runs great and seems a little quieter.
-let it run for an hour or so as I put everything away and cleaned up after myself. No heat, all good. Multiple feed / speed changes all good as new.
This points to either a bearing going out, the rapid feed mechanism acting up but most likely slipping out of gear due to a feed-speed selector dial issue.
I'm confident in running the machine as is until I can get the operators side panel off and clean - inspect the dials and look into the gearbox directly. I did run a mini camera into the oil fill and drain holes and the teeth appeared normal for a 50 yo machine.
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