Just received my new ZX45 (Chinese clone of RF45) square column mill.
Got it home and unloaded it but need to disassemble into pieces to move to
basement shop. So far so good BUT after three hours I still can't figure out how to remove the gear head. On this machine it rotates and has three bolts to lock rotation. Loosening them feels like there is still a center bolt holding things in place. This center bolt is also shown in the exploded parts view.

After removing the z axis screw and nut you can see what looks like the end of the bolt threads from the back access panel of the column. But even after disassembly of the gear box (where you think you'd see the head of this center bolt - there is nothing. (More later on hints to disassemble and reassemble that beast.)

For now, anyones input on getting the head off very much appreciated. Oh - unless I can remove the invisible center bolt then the collar (inside the Z axis tower) on the back side of this 'center bolt' prevents you from sliding the whole thing off of the dovetails - collar hits end of cast in slot in square column.

Help
Dennis

That mill appears to be very similar as the HF geared-head mill I have, except that mine's a round column. Still, the head mounting should be the same or similar.

On mine, those 3 nuts are all that needs to removed, and when doing so, the head actually has to come out (forward) a bit for the nuts to be able to come completely off the bolts. It's possible that the "suction" of thick grease may be holding it from just dropping off and you're thinking there's something holding it back. This is what mine looks like. The photo just cuts off where the 3 bolts are (they can move around in the circular groove, and have dropped to the lower part of the circle since there's no nuts on them. I can take a better picture if you wish, since the mill is currently apart like this... http://narwani.net/neil/mech/Mill_Column.jpg

Thanks - I finally got it off - had to support it via crane and use a lot of
muscle to break it loose - all is fine.

Next job is to figure out how to reassemble gears and bearings into head.
gears and bearings came off with head cover plate - not sure of best way to get everything lined up - ESPECIALLY the gear change pawls - small brass curved block that have to fit into gear change collars - any thoughts

Dennis

Hi, I Have had my gearbox all apart and you have to get the shafts pulled out of the top cover and reassemble them into the lower unit along with the gear change sliders and then just bolt the lid back on. Dave

The shafts that are pressed into the top cover of the gear box - did you use a hydraulic press - mine seem pretty snug - I take it you have to do it that way to make sure you give the brass shift pawls properly aligned.
dk

Hey, On the top of the lid there are 2 or 3 round sheet metal covers that are over the holes bored in the lid for the shaft bearings. You have to scrape the paint and bondo off the top of them and dig the covers out. They will get destroyed in the process, dont worry about it the bearings are sealed anyway. Now you can tap the shafts out from the top. After I got them out I buffed the top part of each shaft by hand a little with some emory cloth so they would have a nice slide in fit into the bearings instead of that way too tight press fit. It is fairly obvous where the shifter sliders ride in the slots in the change gears. Caution: One of the sliding gears has a spring and a single ball bearing that rides inside the shaft and provides a detent that holds that gear either up or down, so watch and make sure nothing goes flying. Even though the transmission is a wet design the bearings are sealed so you can repack them with some good grease while you have it apart. On mine I bolted 2 tabs on top of the lid while I had it apart for counterbalance cables to connect to. I have a zx7045 from wholesale tools. Sorry I didnt take any pics inside my gearbox, but heres one that shows the tabs in front of the spindle motor.

Cable mount pic The cover was drilled and a bolt goes through the tabs and locktited nut are on the underside of the cover. You have to make sure you miss the webbing on the inside.

Dave - great advice -thanks. We'll be reassembling our ZX7045 over the holidays. Just got it all disassembled and moved into the basement - now to clean up and reassemble. CNC will be on tap over the next few months. I need to check on that spring and ball detent - don't seem to remember it after disassembly of the gear box. I will say that it was pretty noisey on a short power up test when I first brought it home - longer term we might think about belts and VFD.... Start a new thread if you'd like to share some more of your Wholesale Tool 7045 experience.
Dennis

Curious -- why did you remove the top plate if you just wanted to move it? When I removed the motor on mine, I did not have to take off the top cover, so no gears came out. I'm pretty sure the head on mine is the same as yours. Either way, if you can take some pics of what you're up against, it would be great for when I have to open mine up.

Thanks,
-Neil.

Neil - I took the top of the gear box off to see what was inside - the lube with thick and very tacky oil not unlike pure STP - will replace with a good gear oil. Also found evidence of sand in the corners. Thought I'd better check since the gear train was pretty noisy. We'll clean it up and at least know what to expect if there are any future issues with bearings etc.

I run Shell rotella full synthetic 5w40 oil in mine and it got a lot quieter. I have heard other people run atf in them, but I like the shell. I think most (gear) oils are way thicker than necessary. Dave

In automotive apps, I also once used to think that gear oils were thicker than necessary, but I changed my mind once I realized how it thins out at higher temps.