Repair History - Click On Picture For Detailed Repair Information
Mori Seiki MV-65 Spindle Repair
Mori Seiki MV-65 Spindle Rebuild Coolant entered the interior of this spindle causing the grease to wash away from the front roller bearings. Much like running a car without oil once the bearing lubrication is compromised it’s really a matter of time before failure. Possible cause of failure: Catastrophic failure of the #1 front roller. Bearing […]
Mori Seiki NLX2500 Spindle Repair
Mori Seiki NLX2500 Spindle Rebuild This repair had been started by our customer but after they got into it they decided the best route would be to send it to Northland Tool for repair. We found the front bearings were worn and the outer front bearing spacer needed to be replaced. Our machining department manufactured […]
Mori Seiki NH4000 Spindle Repair
Mori Seiki NH4000 Spindle Rebuild Possible cause of failure: Shaft taper is worn, tooling rocks in the taper. Drawbar force is 1420lbs incoming (low for a Big Plus taper), likely from being taper ground. Taper coolant plungers are worn out. Gripper fingers are worn. #1 front bearing is bad, probably from a crash. Customer supplied […]
Mori Seiki NH5000 Spindle Repair
Mori Seiki NH5000 Spindle Rebuild Possible cause of failure: First and second bearings failed. The number two bearing spun on the shaft and in the housing. Shield for the oil line was snapped off. Coolant plungers need to be replaced. Drive dogs are hit, need to be replaced. Inner spacer was destroyed by the bearing. […]
Mori Seiki SVD 403 Spindle Repair
Mori Seiki SVD 403 Spindle Rebuild Possible cause of failure: Bearings are noisy. Taper is bell mouthed with one chip. Big-Plus test bar runout = 24-30µ. Drive dogs have been modified. Customer supplied a standard CT tool and knob. Repair action: Clean, inspect overall dimensions. Replace bearings, Bellevilles, plastic oil lines, ferrules, o-rings, 10mm front cover balls […]
Mori Seiki SL-00 Spindle Repair
Mori Seiki SL-00 Spindle Rebuild Possible cause of failure: Spindle came in missing the front cover bolt’s. Rear roller failure from coolant contamination, rear housing cover is coated with coolant sludge. Lathe OD taper, face and shoulder have wear. Came in with out the chuck alignment pin, drive pulley, pulley nut, pulley key (we will […]
Mori Seiki MH50 Spindle Repair
Mori Seiki MH50 Ceramic taper replacement and spindle rebuild Possible cause of failure: Ceramic taper insert is broken, with pieces missing. Due to damage, the drawbar force could not be checked. Front shaft journal were the angular contact bearings ride is fretted and undersized by -8/-10 Rear drive coupling upper […]
Mori Seiki SH400 Spindle Repair
Mori Seiki SH400 Spindle Repair Possible cause of failure: Front bearing failure from coolant contamination,#1 has the most contamination. Shaft taper is bell mouthed. Drive dogs have slight cosmetic wear Splash ring and coolant plunger assembly’s are worn Recommended action: Clean, inspect overall dimensions. Grind, plate and finish grind the taper. Replace bearings, o-rings, oil […]
Mori Seiki SH403 Spindle Repair
Possible cause of failure: Front bearing failure from coolant contamination, full of dried coolant. Shaft taper has a small window on the leading edge of taper Repair action: Clean, inspect overall dimensions. Kiss grind shaft taper(taper may still have a slight window after kissing but will be functional,if taper can not be saved it may […]
Mori Seiki NH5000 Spindle Repair
Possible cause of failure: Missing coolant plungers. Received in with no drawbar or tail parts. 1 Brass crush ring stuck in the housing from oil mist line. Slight rub out on the ID of the front cover and ID of front shaft. Front bearings coolant contaminated. Chrome has flaked in front taper Repair action: Clean, […]
Mori Seiki CL 20A
Possible cause of failure: Nose of shaft is bent, excessive run out. Face has 40µ runout,taper has 40µ runout,front shoulder has 22µ run out. Front taper is 10µ egged,thrust bearing journal has 7-8µ run out. Front bearings are slightly contaminated. Spindle was crashed Pulley compression ring is damaged. Repair action: Clean, inspect overall dimensions. Replace […]
Mori Seiki SL-15MC
The owner of this spindle came to us after they had tried to repair this spindle themselves. It has a hydraulic nut to capture the front bearings and they found they were not equipped deal with the nut. When they installed the spindle into the machine the nut would loosen and give them end play. […]
Mori Seiki NV5000
BIG PLUS Taper 12,000 rpm This spindle was crashed causing damage to the front bearings and the BIG PLUS taper. We needed to grind plate grind the taper to bring it back to manufacturers specifications. Our final QC showed we had less than 2 microns run out on a 13 inch BIG PLUS test bar […]
Mori Seiki SH500 BIG PLUS
This customer was referred to us by another of our customers. This spindle had been repaired several years ago and during that repair the taper was kiss ground. Unfortunately that made the BIG PLUS taper unusable. We were able to repair the taper to BIG PLUS standards an rebuild the spindle.
Mori Seiki SH40
The taper of this spindle had build up causing tool run out. The front bearings were contaminated and the front housing was over sized. All these factors contributed to bad part finish that eventually lead to our customer to send the spindle to Northland Tool for repair. We ground plate ground the front housing and […]
Mori Seiki SL154 Spindle Repair
6,000 rpm Grease lubricated Magnetic Rotor This spindle was crashed causing bearing failure and alignment pin damage. What makes this repair unique is the magnetic rotor. Special care must be taken throughout the repair process to make sure the rotor is not damaged or picks up contaminates. Our technicians are required to remove all necklaces […]
Mori Seiki MV40 Spindle Repair
12,000 rpm We repair several spindles from our customers in Canada. This spindle came to us in very rough shape. The spindle had a damaged shaft taper, broken drive dogs, coolant plungers were worn and the shaft journals were undersized. We were able to repair the drive dogs in our machining department and fix the […]
Mori Seiki CL203B
3500 RPM The initial concern for this customer was the sound of the bearings during rotation. Upon further inspection the temperature of the spindle had elevated. This was caused by contamination in the bearings, both front and rear. Our evaluation showed run out in the taper and face on the front of the shaft. We […]
Mori Seiki MH-630 spindle repair
6,000 RPM This spindle came in with the coupling for the drive motor attached to the rear of the shaft. Our incoming evaluation found the mating surfaces of these two parts was fretted and out of specification. This was causing vibration in the spindle resulting in poor part finish. This is one of the reasons […]
Mori Seiki SV500 Spindle Repair
This Mori Seiki spindle was sent to us from a company in Italy to repair. Their sister plant here in the United States has been a customer of ours for spindle rebuild over 20 years. The spindle was completely disassembled when we received it. At times this makes it difficult to determine the cause of […]
Mori Seiki Spindle Repair
Mori Seiki has been a mainstay in the machine tool world since 1948. They are known for quality and reliability. Mori Seiki spindles share the same qualities as the Mori Seiki machine. Mori Seiki spindles are built with longevity and quality in mind. Mori Seiki invests heavily in updating their spindle designs and provides it’s customers with one of the best machine tool spindles on the market today.
Northland Tool & Electronics repairs most every type of Mori Seiki spindle including Mori Seiki turning center spindles, Mori Seiki vertical machining center spindles, Mori Seiki multi axis turning center spindles, Mori Seiki horizontal machining center spindles and Mori Seiki CNC Lathe spindles.
Common Problems With Mori Seiki Spindles
Here are just a few of the actual failures we have found in Mori Seiki spindles. Mori Seiki spindles are very well built from the OEM and usually last for extended periods of time but eventually they wear out from use.
Some Mori Seiki spindles are made with specialty bearings that are designed to allow better lubrication flow to the raceways. Many independent spindle rebuilders modify the lubrication delivery system to allow them to use cheaper bearings. Northland Tool & Electronics only uses bearings that have the same design and quality characteristics as the OEM originals.
Northland Tool & Electronics is capable of repairing most every Mori Seiki spindle made including damaged ceramic tapers, damaged drive dogs, crashed spindles, electrical issues and most every cause of failure that may happen.
When sending in your Mori Seiki spindle for repair please include all of the rotating parts including the drawbar system. We like to balance everything as an assembly and make sure the drawbar system is functioning properly and has the correct tool holding force.
Heavy taper damage, spindle was crashed.
Front journal damaged when spindle crashed.
Drive dogs are damaged.
Bearings are worn.
Drawbar, lube fittings and coolant nozzles missing.
Taper has 8 microns run out and is bell mouthed.
Contaminated front bearings.
Housing is oversized by double ISO.
Taper has 6 microns run out.
Front and rear bearing failure from coolant contamination.
Bearings and housing are internally rusted.
Front and rear covers are damaged.
The bearings appear to have had catastrophic failure.
Outer bearing spacers have been modified.
Front journal has a cut mark from someone cutting off the inner bearing races.
Rear roller nut loosened allowing the rear roller to lose preload.
This caused shim material from the bearing spacer to fall into the front bearings so they failed also.
The rear nut was missing its locking set screws, this allowed the rear nut to loosen.
The coupling journal and rear roller journal are out of ISO.
Taper has run out.
Drive coupling ID is out of ISO.
Catastrophic failure of the #1 bearing causing damage to the labyrinth ring
Came in missing drawbar, rear bearing nut, taper coolant nozzels and holder.
Inner race of the front bearing race is cracked and cages are missing.
Gripper fingers are worn.
Taper is damaged.
Bellevilles are worn.
Drive dogs are damaged.
Rear housing is oversized.
Damaged front cover.
Oil drains were clogged.
Bearings are worn
Shaft taper is damaged
Drive coupling is worn
Coupling band on the shaft are fretted and worn.
Drawbar force is low
Mori Seiki Models We Commonly Repair
- CL 253B
- NMV5000 DCG
- TL 5
- MT 253
- TL 500
- MT 253S/1000
- NT3150 SZ
- MT 4000S/4000
- NT4250 SZ
- Dura Turn 2050
- SL 5A
- NT5400 / 1800SZ
- SL 603C
- Duraturn 2050MC
- NT6600 DCG
- SL 65MC
- MS850 G
- NH 6300
- NVD 5000
- NH5000/40 DCG
- MV JR
- NL 2500
- SL-204 SMC