Re:CHNC-1 Retrofit & Upgrades

the Max it allows, which is 10m/min in each axis
10m/min was the Z before, but X was only 5m/min due to motor size and gearing on the old setup.

i just made it all 1:1 as i put bigger motors on so i have the same torque still

Hello, new here and I know this is a really old post, but I didn’t see another way to make contact. 

I am currently retrofitting a CHNC II+ and I would love to have some more information about the turret servo. What you used, how you mounted it, etc. 

I can’t make out much in the photo bucket pictures attached. 

Thanks Gary Breiling

Gary, remove the e-mail, automated robots will use it to spam you with everything.

Hi Gary

Is yours a CHNC 1/2/3 model?
the 3 already had a servo driven turret as it had a latter fanuc control and many upgrades

1/2 i dont think there is much difference realy only controll and few functional things


the servo size i used was not very big, i think 200w or so.. just fits in the space i can check size if you wish, was a Mitshibishi i had laying around.

then i made an adapater to mount to the motor, with a custom shaft that push's on motor end and gear mounts like the old air motor end.. everything fits in the original hole no casting mods. even back cover refits.

i might have the solid model for the adapter i will need to check in the week when at work if it would help?

linuxcnc i just use a basic PID loop and a quick hal.comp i made but there might be a comp with in linuxcnc now to use.

it works yes, but the gears are very very unmeshed and not much you can do, yes you can rotate shaft/gear to mesh but still not perfect as there is a internmediate gear under the cover to side of the turret. this has a lot of play in it..

if i was todo this again i would look at can you put two gears that are adjustable to take care of 90% backlash? i think yes maybe. as some times the turret can get a little out of postion and not lock down on the pads becasue backlash is unknown.. but as it has taper lock blocks (mine does not have a earth ring, just 4 blocks) so very rare you dont get a lock.

the comp just index's the motor required encoder distance to the next station.
i used the old "absolute encoder" which just a hall effect sensor for position, so on turn on turret knows where it is tool wise. motor just set to 0 on encoder count on PID


i did look to see if was posible to mod the casting and put the work out of the back (z slide direction) but thats alot of work, would be best way and thats why fanuc/hardinge did it that way later on.

but it is way better than the old air motor issues you get. and the old catch plate that would always give a issue after awhile..

sorry long post now, i hope it kind of makes sense

Thanks Robh, mine is a CHNC 2. I would be grateful for information on the servo you used and definitely the adapter.

I wonder if Hardinge gets away with the backlash by rotating the same direction all of the time. Without understanding completely I was thinking it could be set up like a rotary indexer and just move a certain number of degrees for each tool position.

I think what you have done is pretty rare and impressive and I appreciate the conversation and whatever help you can give.

Thanks Gary Breiling

Robh, I am not sure where you are located, but I will be in England in May if it would work out and I might be reasonably close I would enjoy seeing how you modified the turret. Gary