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Hardinge CHNC 4 retrofit

After a couple of weeks tracking down leaks -the turret system was the loudest and was blowing full air out of the solenoid manifold - port 7. I replaced the solenoid, put new seals in the check valve and finally went into the turret to replace the quad rings and O-Rings.
The turret seals fixed the leak but I had to go in and out a couple times...there is a small o-ring that seals the port that raises the turret, and I forgot it - It wasn't on my list of replacements but there was obvious air leak around it and I have a bunch of small O-rings....The big U seal has been impossible to find; 1/4 inch tall 7.5 inch OD
All is not perfect; the turret raises up but does not spin. There are a couple round reliefs on the lower cylinder plate and I wonder if they need to be oriented toward a certain feature. I will be looking at the air motor next.
Now that I can hear all the other stuff going on I will have to address the collet closer...
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Still on the search for air leaks. I am now looking at the turret stop solenoid; it has air bypassing when inactive and no air bypass when activated... I am looking at this now because I am having turret stopping issues. I have slowed down the turret, adjusted the encoder - not to a particular spec just to about the center position where it reads the position. I think the turret issues may stem from sealing the turret and now more air is going to the correct places. As a side note the good thing (?) is I can't hear it when the cover is on 9-). the bad news is it's leaking. I also need to look at the stop cushion. I'm sure the Orings there need attention!


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One of my next tasks is to replace the seals on the collet closer. The last few days have been fun as I am able to turn some parts. I added a Bostar 5C collet chuck that allows me some extra flexiblity since I have several 5c Collets. My initial impression is that it takes up a lot of Z space. But after you get used to all the moves it takes to load collets and parts it's not bad. Now I want to get back to being able to easily open and close the collet closer.
I ran the machine with the collet closer out for a bit but the ring that holds it on rattles - I don't think it comes off but it is annoying. Maybe I could make a plate to hold it on or just freakin' hurry on the closer rebuild...! What is normal when the closer is out?


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    Bostic Chuck.png
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In my quest to seal up as many leaks as possible there are two areas I will work on this week. The collet closer and the stop cushion.
I was wondering if anyone has any pictures of the stop cushion. I have a manual the kinda show where it is - I'm thinking I have to remove the plate on the back side of the carriage. Bonus points for any seal, o-ring info and pictures.

I made an initial attempt to get the nut off the collet closer - used some heat and a cheap spanner - didn't work, then made a better spanner and now I'm thinking about adding a bigger nut in the middle to use with an impact gun. I have read that some are LH thread but I watched a video on rebuilding the closer and he does loosen the nut in the RH direction. I left the closer in the spindle, with it locked, but I may need a better way to hold it...suggestions welcome
I spent about a week adding tools and getting the offsets right.I made some parts via the Centroid conversational program Intercon. I works ok but I learned that their threading data has to be tweaked if you use insert tooling with a sharp nose...One of the items I started was a probe tip to use for tool touch off. It went well until the M3 threads, I later found that fusion 360 was way off on their pitch and thread depth . The good news is that the diameters were withing 0.0003 across five parts. I skipped the threading on two and used a die. Video
As I added more tools I was setting the x offset and inching, no make that sneaking, up to the part and after about 20 clicks I realized the X axis wasn't moving...That was the beginning of last week 4/16/24 and I still haven't resolved the problem. Bottom line is that I tried to use old parts and old wiring and I will replace the servo wiring and try to understand if the servos will still work. I'd like to go AC servos but the Centroid ALLIN1DC is not able to drive them. I will decide soon how to proceed.
A bit of a bad news update; A couple weeks ago my system stopped as I was sneaking up to touch off a tool. I approached very slowly and after several incremental moves I realized my X axis wasn't moving. Long story short; the X axis motor may have shorted and took out the Centroid ALLIN1DC. It blew a fuse but they don't have enough in place to protect other circuits- please tell me I'm wrong. Either way they repaired the board for a cost.
Both servo motors are being refurbished - the one that shorted is getting rewound. new bearings brushes and paint. If there is any good news the cost is less than one new servo motor.
My collet closer is on the bench waiting for an extra hand.

I am revisiting cleaning the coolant tank - I am not able to take it out due to the position of the lathe. There is a sludgy mess at the bottom with a thin layer of liquid on top. My only access is by removing the chip tray that allows access to a 6 inch hole that is a direct path to the tank. I started with a cyclone attachment on my vacuum and got about 3 gallons of liquid out. Picking up the sludge may be possible if I break it up...non practical thoughts say I should build a sled to be able to move the lathe but....I'm looking for a variety of ideas that center around going through a six inch hole ...that has a bar across it 8-(
I stopped at Harbor Freight and got one of those paddles and a barrel pump. We'll see if I can pump chips and strain the liquid and put it back and do it over and over. I get the feeling it may be less than perfect but a step forward is a start...
I ended up using my shop vac with a cyclone separator; still not efficient. It gets the liquid out well but i need to mix the slurry better...still more to go but I got about 4 gallons of chips out. I reused the liquid once - there's about 5 gallons of what is probably a mix of oil and water. The prior owner used water to clean the machine...