Denny, glad it was useful. It took me a bit to learn how to use it but I’m still happy with it. You will and probably have already watched a lot of machinists videos, that helped me a bunch. Jim
Doug, yes you will need to change the gears back, unless you don't need or want to use the power feed on the cross slid for any turning operations. This is because this lathe has only one screw that moves the cross slide. I understand some of the bigger or more expensive lathes have a dedicated lead screw for threading and one for power feed. The problem is the threading setup move the carriage much too fast for normal turning with power feed. If you didn't need power feed, you could simply remove one gear to disengage the gear set. The make a bit of noise especially when new. The gears get easier to change after you do it a few times. Thanks for the comment and question, hope I helped! Jim
Thank you for taking the time to present this, good video. Does the lathe have a method for locking the chuck in place so when you reverse the spindle it doesn't unscrew itself.
At the start of the video you can see a locking clamp screwed on behind the chuck. There are two of these to keep it from unscrewing. That said, you are not supposed to go from fwd to rev without letting it stop first. Also, if you are turning in reverse and the tool catches on the work, I would be concerned that damage could occur to the chuck or locks. I don't see much need at this point for rev work, other that left hand threading...
I am looking at a method of cutting off using an inverted cutoff tool holder (It's called a FoR (Front or Rear) and is available from Bay-Com). It's supposed to cut-off very smoothly without the usual chatter drama. But if used in front of the spindle (the normal way you cut off) the lathe spindle needs to be run in reverse because the cutoff tool is inverted. Mounting in front of the spindle can't be done with a screw on chuck lathe such as the G0750 because the spindle reverse rotation would cause the chuck to unscrew itself and all hell would break loose (hence my question). The solution is to mount the inverted cut-off tool behind the spindle and run the lathe in the normal direction. You appear to be having a lot of fun learning about turning (I'm envious). Good luck
I actually looked at that just the other day. I might try from the back side so it can turn normal rotation. I have had pretty good luck with the typical parting operation, but it really depends on perfect setup. If I can figure out how to get the tool in back I'll make a video of it.
HI Rv Jim...you may have found out by now, 6 years later, but after some very careful observing, I see you're using to cross slide to advance the cut and this is NOT how you do it. The cross slide is set to "0" at the touch off and is returned to "0" after each pass. The compound slide is the one that advances into the cut, hence the 30' angle of the compound. At the end of each pass, don't touch the compound. Back the cross slide out several thousands, and return the carriage to the start of the thread. Return the CROSS SLIDE back to "0", and advance the COMPOUND a few thousands into the depth of cut, and start your next pass. Continue in this way until the threading is complete. I hope this helps you or others seeing this video if you don't know it already.
Thanks for posting. I have a couple of questions concerning the G0752. I'm planning on buying a G0602 or G0752 and the only difference (besides price) that I see is the G0752 has variable speed drive. In your experience is the variable speed option worth the $400 increase in price? When not cutting threads, do you have to remove any gears at all to change speeds? To put it another way, do you only switch gears when cutting different thread pitches?
Luchi Sm, I do not cut threads very often and that is the only time I change gears. The VFD variable speed control is worth the extra cost in my opinion. I use that feature almost every time I use the lathe. For instance, turning aluminum is usually a high speed operation, and then to dress up the corner after facing a part, I use a hand file with the speed turned down to slow. I have seen several videos where people do their own motor and VFD conversion, but I don't think it is any cheaper? Thanks for watching! Jim
What is your overall opinion of this lathe? I'm about to purchase one and I would like to know what you think of the quality and accuracy of this lathe, I would prefer an American made lathe but these Chinese lathes are about all that are out there (even the lathes with American names are really made in China) I would just like to know if overall you're satisfied with your purchase...Thanks
Ted, I feel like I have used if a fair amount in the short time I have owned it. I still like it and don't regret the decision. Like you, I would love to have a nice restored similar sized SB but I don't see them here in central Iowa. I wouldn't get a lathe without the VFD. I use the variable speed every time I use it to adjust speed for the best finish. There are a handful of things I wished they had done different but overall I am pleased. One typical item is that it really would be nice to have a cam lock on the tailstock. I made a little machine jack that I put under the tool when parting and that REALLY helps to solve the flex and rigidity issues when parting stock. Maybe I should make a "two months later review"? If you have other specific questions, fire away, happy to help. Jim
Jim, Thanks for the reply! it would be appreciated by many if you put up a few more videos if you have them, I do agree the VFD is the way to go, I had that feature in a Mini-lathe and it's the way to go. The two month later review will be great if you choose to do that....Ted
RVJimD some of the cross slides were defective and gapped at the front causing flex. I warrantied mine and it solves the issue. Prior I had to use a hacksaw blade for shim stock or the tooling would kick down a hundred thou.
Bob, I think you are correct. It does allow forward and reverse rotation of the chuck and the carriage moves left or right. So, if you mounted a tool upside down and then run the chuck reverse that would let you cut threads away from the headstock. I think that would be a typical right handed thread. My biggest reason for not doing much single point threading is the need to change the gears back and forth. You need one setup for turning to size in preparation for the threading operation, then change gearing for the threading and then back for normal operation. Hope this helps and thanks for the question! Jim
Tom, the change knobs on the front and the gears inside the left end are for setting the speed/rpm of the lead screw for threading or feed rate while turning. This lathe also has a step pulley which set the three different rpm ranges of the chuck itself. I hardly ever change the belt position, although the it isn't too difficult. With the electronic speed control you get a really nice instant control of the rpm. Thanks for the comment, Jim
Yes, I figured that, but I have to wonder what good is a quick change gear box for the lead screw if you still have to change out the gears? You change the gears for the lead screw on lathes without a quick change gearbox.
Ya, I'm not sure. It lets you set an extremely low feed rate with the gears, and still have some control using the quick change knobs. When I bought the lathe (my first) I don't think I understood all of this. I am not sure, but I think a similar sized lathe with complete quick change would be much more expensive. The only downside is when you actually plan to cut threads. You need slow feed for the prep work and then a gear change for the threading, and then gear change back to a normal feed rate. Jim
At about 6:30 you mentioned the stacked gears where one is not used. I just looked at a different threading video for the G09972Z which appears to use the same threading gear system. It too has the 127:120 stacked gears. In that video the author shows how the pair is flipped over for use with the metric threading. I was curious so I ran the math and it is interesting. If you compare a metric 1mm pitch thread to an Imperial 24 pitch thread the a,b gears are the same, and the knob settings = A,I are the same. The only difference is the imperial uses the 127 tooth gear and the metric uses the 120. Comparing linear travel of both after 24 revolutions; Metric = 24mm, while Imperial = 25.5mm. The ratio of distance traveled is 25.4/24 = 1.058333... Interesting this is the exact ratio of 127/120 = 1.058333... Amazing. mystery solved. Interestingly the only other a,b gears that work well with metrics are the a=35 tooth, b= 70 tooth selection, giving a pitch length that is 1.5 times as long. Because the metric gears are based on standard linear increments, whereas the imperial gears are spaced geometrically, the spacings between thread pitches is much different on the imperial system which uses 1"/n pitch lengths. Grizzly would have needed to provide more intermediate (127/120) pairs to make more metric threads.
Eidetic, ya it is sorta hard to follow looking at their manual. It seemed to me that they specifically indicated a gear placement but it wasn't being driven or driving another? I'm not sure I have cut threads since I made the video. It is just enough of a pain that I keep the feed screw speed (gear ratio) to yield the slowest and hopefully best finish for turning operations. Thanks for the comment!
Ya, I can really see where turning to a diameter than swapping for threading then back to the slow setting could be a real pain. I have been thinking of an electronic lead screw (els) setup instead of the change gears. I can see my self cutting thread as much as doing anything else. There is a guy that programmed an arduino for this: th-cam.com/video/R2N3Vt5ZQ9w/w-d-xo.html First I have to get a lathe, and before that I think I should move so I don't have to move it twice. Cheers.
I was wondering if you knew if that lathe is too loud for doing work in an apartment? I would love to buy it, but may have to stick with the 7" x 16" for the time being.
Nice vid, I just bought one of these myself. I had been doing machine work most of my life and I always disengage the 1/2 nut. I was taught as long as you catch it on the right number you will be ok. It has never failed me but I have not tried to thread on this lathe yet. Still trying to figure out the gear setup for the threads. I always used big clausing and south ben lathes where I never had to change the gears. Do I have to change the gears back after threading? I am trying to cut a 5/16 X 14 thread. I know its an odd size but is what I need to cut. Once I figure out the setup I will let you know how it goes. I don't want to change these gears no more then I have to. Any suggestions? Thanks in advance. Doug
Thanks for sharing! I just got this lathe today, and am pretty excited to cut threads for the first time. This helped a lot!
Denny, glad it was useful. It took me a bit to learn how to use it but I’m still happy with it. You will and probably have already watched a lot of machinists videos, that helped me a bunch. Jim
Doug, yes you will need to change the gears back, unless you don't need or want to use the power feed on the cross slid for any turning operations. This is because this lathe has only one screw that moves the cross slide. I understand some of the bigger or more expensive lathes have a dedicated lead screw for threading and one for power feed. The problem is the threading setup move the carriage much too fast for normal turning with power feed. If you didn't need power feed, you could simply remove one gear to disengage the gear set. The make a bit of noise especially when new. The gears get easier to change after you do it a few times.
Thanks for the comment and question, hope I helped!
Jim
Had to wait till the end to see the best partner. A good shop dog and there will never be a bad day. Thanks
Thank you for taking the time to present this, good video. Does the lathe have a method for locking the chuck in place so when you reverse the spindle it doesn't unscrew itself.
At the start of the video you can see a locking clamp screwed on behind the chuck. There are two of these to keep it from unscrewing. That said, you are not supposed to go from fwd to rev without letting it stop first. Also, if you are turning in reverse and the tool catches on the work, I would be concerned that damage could occur to the chuck or locks. I don't see much need at this point for rev work, other that left hand threading...
I am looking at a method of cutting off using an inverted cutoff tool holder (It's called a FoR (Front or Rear) and is available from Bay-Com). It's supposed to cut-off very smoothly without the usual chatter drama. But if used in front of the spindle (the normal way you cut off) the lathe spindle needs to be run in reverse because the cutoff tool is inverted. Mounting in front of the spindle can't be done with a screw on chuck lathe such as the G0750 because the spindle reverse rotation would cause the chuck to unscrew itself and all hell would break loose (hence my question). The solution is to mount the inverted cut-off tool behind the spindle and run the lathe in the normal direction. You appear to be having a lot of fun learning about turning (I'm envious). Good luck
I actually looked at that just the other day. I might try from the back side so it can turn normal rotation. I have had pretty good luck with the typical parting operation, but it really depends on perfect setup. If I can figure out how to get the tool in back I'll make a video of it.
HI Rv Jim...you may have found out by now, 6 years later, but after some very careful observing, I see you're using to cross slide to advance the cut and this is NOT how you do it. The cross slide is set to "0" at the touch off and is returned to "0" after each pass. The compound slide is the one that advances into the cut, hence the 30' angle of the compound. At the end of each pass, don't touch the compound. Back the cross slide out several thousands, and return the carriage to the start of the thread. Return the CROSS SLIDE back to "0", and advance the COMPOUND a few thousands into the depth of cut, and start your next pass. Continue in this way until the threading is complete.
I hope this helps you or others seeing this video if you don't know it already.
Thank you so much for posting this. Threading isn't so scary now!
Thanks for the video and for explaining everything so well. Well done!
+Joseph Stokes, you are welcome, thanks for watching. Jim
Thanks for posting. I have a couple of questions concerning the G0752. I'm planning on buying a G0602 or G0752 and the only difference (besides price) that I see is the G0752 has variable speed drive. In your experience is the variable speed option worth the $400 increase in price? When not cutting threads, do you have to remove any gears at all to change speeds? To put it another way, do you only switch gears when cutting different thread pitches?
Luchi Sm, I do not cut threads very often and that is the only time I change gears. The VFD variable speed control is worth the extra cost in my opinion. I use that feature almost every time I use the lathe. For instance, turning aluminum is usually a high speed operation, and then to dress up the corner after facing a part, I use a hand file with the speed turned down to slow. I have seen several videos where people do their own motor and VFD conversion, but I don't think it is any cheaper? Thanks for watching! Jim
What is your overall opinion of this lathe? I'm about to purchase one and I would like to know what you think of the quality and accuracy of this lathe, I would prefer an American made lathe but these Chinese lathes are about all that are out there (even the lathes with American names are really made in China) I would just like to know if overall you're satisfied with your purchase...Thanks
Ted,
I feel like I have used if a fair amount in the short time I have owned it. I still like it and don't regret the decision. Like you, I would love to have a nice restored similar sized SB but I don't see them here in central Iowa. I wouldn't get a lathe without the VFD. I use the variable speed every time I use it to adjust speed for the best finish. There are a handful of things I wished they had done different but overall I am pleased. One typical item is that it really would be nice to have a cam lock on the tailstock. I made a little machine jack that I put under the tool when parting and that REALLY helps to solve the flex and rigidity issues when parting stock. Maybe I should make a "two months later review"? If you have other specific questions, fire away, happy to help.
Jim
Jim, Thanks for the reply! it would be appreciated by many if you put up a few more videos if you have them, I do agree the VFD is the way to go, I had that feature in a Mini-lathe and it's the way to go. The two month later review will be great if you choose to do that....Ted
RVJimD some of the cross slides were defective and gapped at the front causing flex. I warrantied mine and it solves the issue. Prior I had to use a hacksaw blade for shim stock or the tooling would kick down a hundred thou.
can you thread in the direction from headstock to tailstock with this lathe? I get the impression you cannot
Bob, I think you are correct. It does allow forward and reverse rotation of the chuck and the carriage moves left or right. So, if you mounted a tool upside down and then run the chuck reverse that would let you cut threads away from the headstock. I think that would be a typical right handed thread. My biggest reason for not doing much single point threading is the need to change the gears back and forth. You need one setup for turning to size in preparation for the threading operation, then change gearing for the threading and then back for normal operation. Hope this helps and thanks for the question! Jim
Ozy, hi. I don't have an indicator that can read better than .001 and I don't think I know how to setup to measure the bed flatness.
Jim
HI,
can you please tell how much the amount of the runout in the spindle and is this bed has .0004 total flatness ?
Please don't shout sir! Happy holidays. Great video.
Sine you have to change the gears anyway, what is the advantage of the quick change gear box on this lathe? Is it obtain various speed/reed ranges?
Tom, the change knobs on the front and the gears inside the left end are for setting the speed/rpm of the lead screw for threading or feed rate while turning. This lathe also has a step pulley which set the three different rpm ranges of the chuck itself. I hardly ever change the belt position, although the it isn't too difficult. With the electronic speed control you get a really nice instant control of the rpm. Thanks for the comment, Jim
Yes, I figured that, but I have to wonder what good is a quick change gear box for the lead screw if you still have to change out the gears? You change the gears for the lead screw on lathes without a quick change gearbox.
Ya, I'm not sure. It lets you set an extremely low feed rate with the gears, and still have some control using the quick change knobs. When I bought the lathe (my first) I don't think I understood all of this. I am not sure, but I think a similar sized lathe with complete quick change would be much more expensive. The only downside is when you actually plan to cut threads. You need slow feed for the prep work and then a gear change for the threading, and then gear change back to a normal feed rate. Jim
At about 6:30 you mentioned the stacked gears where one is not used. I just looked at a different threading video for the G09972Z which appears to use the same threading gear system. It too has the 127:120 stacked gears. In that video the author shows how the pair is flipped over for use with the metric threading. I was curious so I ran the math and it is interesting.
If you compare a metric 1mm pitch thread to an Imperial 24 pitch thread the a,b gears are the same, and the knob settings = A,I are the same. The only difference is the imperial uses the 127 tooth gear and the metric uses the 120.
Comparing linear travel of both after 24 revolutions; Metric = 24mm, while Imperial = 25.5mm. The ratio of distance traveled is 25.4/24 = 1.058333... Interesting this is the exact ratio of 127/120 = 1.058333... Amazing. mystery solved.
Interestingly the only other a,b gears that work well with metrics are the a=35 tooth, b= 70 tooth selection, giving a pitch length that is 1.5 times as long.
Because the metric gears are based on standard linear increments, whereas the imperial gears are spaced geometrically, the spacings between thread pitches is much different on the imperial system which uses 1"/n pitch lengths. Grizzly would have needed to provide more intermediate (127/120) pairs to make more metric threads.
Eidetic, ya it is sorta hard to follow looking at their manual. It seemed to me that they specifically indicated a gear placement but it wasn't being driven or driving another? I'm not sure I have cut threads since I made the video. It is just enough of a pain that I keep the feed screw speed (gear ratio) to yield the slowest and hopefully best finish for turning operations. Thanks for the comment!
Ya, I can really see where turning to a diameter than swapping for threading then back to the slow setting could be a real pain.
I have been thinking of an electronic lead screw (els) setup instead of the change gears. I can see my self cutting thread as much as doing anything else. There is a guy that programmed an arduino for this:
th-cam.com/video/R2N3Vt5ZQ9w/w-d-xo.html
First I have to get a lathe, and before that I think I should move so I don't have to move it twice. Cheers.
Eidetic, ya that is exactly right. It would be okay if you didn't have to do the gear swap at least twice. The arduino setup sounds cool!
I was wondering if you knew if that lathe is too loud for doing work in an apartment? I would love to buy it, but may have to stick with the 7" x 16" for the time being.
Kyle, I think it would be okay. I don't really notice much noise and I don't feel like I need ear protection or anything like that.
RVJimD Good to read, thanks :)
Nice vid, I just bought one of these myself. I had been doing machine work most of my life and I always disengage the 1/2 nut. I was taught as long as you catch it on the right number you will be ok. It has never failed me but I have not tried to thread on this lathe yet. Still trying to figure out the gear setup for the threads. I always used big clausing and south ben lathes where I never had to change the gears. Do I have to change the gears back after threading? I am trying to cut a 5/16 X 14 thread. I know its an odd size but is what I need to cut. Once I figure out the setup I will let you know how it goes. I don't want to change these gears no more then I have to. Any suggestions? Thanks in advance. Doug