X Axis Backlash Fanuc Triac

All info relating to the Denford Triac series of CNC milling machines

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jamesgates1000
CNC Apprentice
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Posts: 77
Joined: Sat 01 Aug , 2015 9:23 am
Hardware/Software: 2001 Cyclone with toolchanger and Fanuc 21i control
Serial number - H00913.
Voltage 415V F.L.C 20A 50Hz 3Ph

1997 Triac VMCwith toolchanger and Fanuc O-M control
Serial number - 70826B.
Voltage 415V F.L.C 30A 50Hz 3Ph

X Axis Backlash Fanuc Triac

Post by jamesgates1000 » Thu 28 Jul , 2016 11:03 am

Hi I have put a clock on my triac table and i can move the handwheel 0.05mm before the table moves, also i can push and pull the table by the same amount. I guess that this is some backlash and can be solved by adjusting gib strips and tightening tab nut.
I have taken the cover off the lefthand end of the table to reveal the motor, the motor is attached to a part by 4 bolts and this part in turn is attached to the table by bolts.
My question is where do I go from here to get to the tab nut?

toby1995
Posts: 30
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Hardware/Software: Denford VR Milling
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Re: X Axis Backlash Fanuc Triac

Post by toby1995 » Thu 29 Dec , 2016 19:36 pm

i have the same issue, unfortunately the denford forum doesnt seem keen to help people with backlash issues. i have taken my table off the machine entirely to find that my ballscrew nuts are very worn which would explain the nearly 0.07mm backlash i was experiencing. will have to get new ones/get them refurbished.

angel-tech
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Re: X Axis Backlash Fanuc Triac

Post by angel-tech » Fri 30 Dec , 2016 1:46 am

first off download the triac assembly diagrams and you can see what is behind the x axis pulley.

Remove the motor with the plate still attached and then the ballscrew pulley. (there are two grub screws holding it on)

Behind the pulley is the bearing assembly which is held in by a tab nut.

Fold the tabs down on the tab washer or it will strip the inner tab and will be useless.

Carefully tighten the nut until the play is gone, then tighten a small amount more to preload the bearings.

Reset the tab washer to lock the nut.

If the play is not completely removed check again.

jamesgates1000
CNC Apprentice
CNC Apprentice
Posts: 77
Joined: Sat 01 Aug , 2015 9:23 am
Hardware/Software: 2001 Cyclone with toolchanger and Fanuc 21i control
Serial number - H00913.
Voltage 415V F.L.C 20A 50Hz 3Ph

1997 Triac VMCwith toolchanger and Fanuc O-M control
Serial number - 70826B.
Voltage 415V F.L.C 30A 50Hz 3Ph

Re: X Axis Backlash Fanuc Triac

Post by jamesgates1000 » Wed 04 Jan , 2017 21:20 pm

Thanks Angel-tech, but i had already got the drawing and got rid of the backlash.

Now I need to replace my spindle bearings and they feel rough when i turn the spindle and very noisy when running, do I need any special tool to remove the bearings from the casting and from the spindle? Bearing puller?

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