G0768 Compound Modification

So the videos you found were pretty well correct about spindle disassembly? My chuck spins around two times when I do it by hand.
 
The grease that I have found used in various Chinese mechanisms is deplorable. My lathe and mill were well used when I got them and this matter had already been corrected by the previous owner. I have worked on several Chinese telescope mounts where precision should be of utmost importance, but like other machinery from over there, the only to get them working properly is to tear them apart thoroughly clean out all of the black tacky muck that they use as grease and grease them properly before reassembly. I also found pieces of metal debris stuck in the gunk and it wasn't from use. The price we pay for these items are low in comparison to the stuff from other manufacturers and this is one of the reasons why. I personally like the fact that you can learn about these mechanisms by rebuilding them from their original state by rebuilding them. Think of it like an education.

CHuck the grumpy old guy
 
Great video. I have a G0765 lathe with the same compound issue. I do believe I will be going this route (or something very similar) to modify mine as well.

Sent from my SAMSUNG-SM-G891A using Tapatalk
 
So the videos you found were pretty well correct about spindle disassembly? My chuck spins around two times when I do it by hand.

These 2 videos helped get a good idea how the spindle is assembled.
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<iframe width="560" height="315" src="
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A big thank you to these YouTuber's for educating us newbies.

Mine now spins about two turns when spinning by hand when in neutral.
Before the repair I might have gotten a 1/2 to 3/4 turn before it stopped.
 
Are you happy with the lathe the lathe overall? I'm trying to decide between the G0768 and the G0602. I like the variable speed on the 768 and from what I gather the ability to cut left hand threads out of the box on the 768. It's my first (ok second, i briefly owned a HF 7x10 and then sold it after losing interest) lathe and will compliment my recently acquired RF-30 Milling machine.
 
Now that I've fixed my spindle problem this thing works great for what I'm doing with it. Do I wish it was bigger, of course, but I think that's the same problem as most lathe owners. This is what fit my budget at the time which is always the deciding factor for me.
Honestly though, I am very impressed on how big of projects I've accomplished with this thing. Can I take 100-200 thou cuts on steel parts? No, but I'm generally never in that big of a hurry and I'm not trying to make my living with it. This is suppose to be a fun hobby and learning experience for me so if it takes a little longer I don't really care.

I do like the variable speed especially if I start getting a little chatter I can make a quick adjustment to the speed to hopefully help the problem.
The only thing I've had issue with is I wish it had a little more torque at the slower speeds of course that comes from the chatter I get when trying to drill 1" holes in steel parts. Maybe that's asking a little much from this machine. I should probably just use a boring bar to get to my larger hole diameters.

One thing that I must mention is that I have not done any single point threading on this thing yet so I can't give you a good assessment of how it performs with that task. I'm sure it's just because of the hassle of changing out those gears but threading is something I want to learn so it's on my to do list just so I can get used to the process.

I don't know if any of this helps with your decision but no matter what way you decide make sure you share your journey with the rest of us.
 
A compound angle of 30º to the spindle axis advances .5" in the x direction for every 1" advance of the compound. An angle of 11.53 advances .2" and an angle of 5.74º advances .1" along the x axis for every 1" of compound advance.
 
Thanks RJ, I'll write those numbers down.
I thought I heard someone talk about it on a YouTube video but then I couldn't find it again so thanks again.
 
Thanks for the feedback! Did you by chance consider the G4000? It's the same price as the G0768, just bigger/heavier and gearbox driven than variable speed. I can't decide between these two machines. As much as I want the variable speed the G4000 seems to be more substabtial and the 9x20 size makes it more appealing.
 
These 2 videos helped get a good idea how the spindle is assembled.
<iframe width="560" height="315" src="
" frameborder="0" allowfullscreen></iframe>
<iframe width="560" height="315" src="
" frameborder="0" allowfullscreen></iframe>
A big thank you to these YouTuber's for educating us newbies.

Mine now spins about two turns when spinning by hand when in neutral.
Before the repair I might have gotten a 1/2 to 3/4 turn before it stopped.

These 2 videos helped get a good idea how the spindle is assembled.
<iframe width="560" height="315" src="
" frameborder="0" allowfullscreen></iframe>
<iframe width="560" height="315" src="
" frameborder="0" allowfullscreen></iframe>
A big thank you to these YouTuber's for educating us newbies.

Mine now spins about two turns when spinning by hand when in neutral.
Before the repair I might have gotten a 1/2 to 3/4 turn before it stopped.
If anyone is going to do this job on the G0768, you need to be aware that the speed sensor is engaged around a sensor ring that is bolted to the spindle. To properly remove the spindle and do the bearings one has to take the front cover off where the speed DRO is and loosen the two Allen head screws to remove the sensor. Then the rest is just like the videos. The second video was very helpful.
 
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