G0602 break in kinda vague help please

Well, I assume the gears have not chipped or broken, so far... Spur gears are not meant to be shifted on the fly, and I would never even try it...

I only raised the issue because we have a new guy running his lathe for the first time. Maybe the G06062 can do it but I've never heard of this and I'd hate to have the OP crash the gears and have to replace them. BUT that doesn't mean it can't be done - just never heard of it myself.
 
@ mikey - no the G0602 does not have synchro its a crunch box, but when I shift I've never had an issue. My gearbox is running an oil level up to the shift knob spindles which on my lathe is about 45mm above the red line on the sight glass. This won't hurt the gearbox as there is at least 40% airspace above the oil, plus I incorporated a breather hole in the filler plug. The reason I run a high level is that NOW all of the lower shaft gears are in an oil bath and when rotating are carrying oil up to the mating gear above. Check out this picture of a G0602 box, lets analyse it.

C III Setting.jpg

Your shift knob on the left of your cover is guiding the center sprocket of the three gear cluster on the bottom shaft left of the web casting you can see in the middle in the above picture. Your right shift knob guides the center sprocket of the three gear cluster on the bottom shaft to the right of the iron web . So therefore looking at your fascia panel your settings on the knobs are III and A for this picture. I've left another post here somewhere where I raised the level because previously I'd looked inside my gearbox when it was running and the oil level was insufficient to carry up to some of the upper shaft gears ie they were running dry. Obviously this has to be detrimental to gearbox lifespan. This is a factory fault. The oil sight glass is too low so when you look at the picture your oil level corresponds to that lower step at the back of the box or at best the underside of the hump in the center web. Which means that the center sprocket on the right hand side is the only gear which may be carrying oil up, and it only meshes with one gear on the top shaft. If anyone has a borescope type camera I'm sure they will be shocked to find this out for themselves. I would like for someone else to verify this and see the results. More oil is always better in this case. (no pun intended)

Also I've always known about and practiced changing gears on a Norton style gearbox whilst the lathe is running. Everyone in my machineshop did it. I'd think any shop floor supervisor that sees an employee powering down a lathe to shift gears on a Norton would have something to say after he's popped a vein.

You would never treat the headstock spindle gears like this, I'm only talking power feedscrew shaft, I hope everyone is clear on this.

@Bob Korves - these gears have a beveled edge, I think they are fully capable of being shifted on the fly.
Remember the first cars, their gearboxes were not much different in construction and even though they had a foot clutch the gears on the output shaft were still being driven by the differential when in motion. There had to be the occasional crunch.
 
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Thanks for that, fitterman. I actually did a search on this subject and some guys do shift feed gears while the lathe is running, too, so I learned something. It's interesting that most lathe manufacturers tell you not to shift gears while running and put it in their manuals and often on the face plates.

On the other hand, I have an Emco lathe for which parts are no longer available so I'll forgo the option and stop my lathe like the manual says; better that than break a gear that I cannot replace.

To the OP, personally, I would follow the manual, at least until the warranty is out. Then you can do what you like!
 
No worries mikey, that's the point of a forum, to listen and learn from others experiences, where you can make your own mind up. I'm glad you learnt something.
cheers Alby
 
I want to thank you all for the help, I will be resealing the front cover of the gear box after I break it in saturday as I noticed its leaking a bit from the lower seam of the gear box cover . I have some good permatex left over from my car rebuilding this year I had 3 vehicles that all had issues from one clutch replacement never let your children use your manual shift truck, 2 waterpumps ,a crank seal , timing belts , head i had to rebuild etc etc . And its good to know that about the gears as I can drive a auto or manual with syncros and at work peterbuilts with out using the clutch lol. I have always been very mechanically inclined since a small child of taking things apart to see how they work and fixing them Aaron
 
With an auto or truck you can "double clutch", disengaging the gears, releasing the clutch, changing the input speed with the engine, and then engaging a new gear set at the correct rpm for them to engage smoothly. It can also be done without using the clutch at all. It takes skill to do it without hurting anything. I have driven a manual transmission car home across town with a failed clutch linkage back in the day, using the starter to get moving in low gear and then shifting by matching shaft speeds. It is not really a very good idea, and there is a good chance of damaging or breaking gear teeth and wearing out any synchros or constant mesh dog clutches while doing it. The lathe does not have a throttle pedal to finely control rpm, and so the gears are forced (crashed) into mesh at unequal speeds, which causes wear or damage. If I worked at a machine shop and the foreman told me to do it, I would, but in my own hobby machinist shop on my own lathe where I will have to fix it and pay the cost, I will be stopping the machine before shifting. YMMV.

Higher end lathes probably have constant mesh gears which are more tolerant of shifting on the fly, are designed with that sort of use in mind, and would recommend that type of use in the manual. A real time saver where time means money.
 
Bob it was meant as a joke I really dont see a need where I would be have to change gears on the lathe while its running. But yes I tried that with my isuzu rodeo and they wont come out of gear once in no matter what the rpms, but it took me a long time to learn our big work trucks that you have to use the clutch just for first gear and then run the low and high gears with no clutch just listening to the engine to know when to shift, down shifting was the hardest to learn on the peterbuilts cause yah have to rev em up a bit before it will slip in but im pretty good at it now.
 
Bob it was meant as a joke I really dont see a need where I would be have to change gears on the lathe while its running. But yes I tried that with my isuzu rodeo and they wont come out of gear once in no matter what the rpms, but it took me a long time to learn our big work trucks that you have to use the clutch just for first gear and then run the low and high gears with no clutch just listening to the engine to know when to shift, down shifting was the hardest to learn on the peterbuilts cause yah have to rev em up a bit before it will slip in but im pretty good at it now.
My comments are not directed at you, or anyone else in particular. I read fitterman1's comments, and while it may work well for him, I felt that it needed a reply before somebody breaks something expensive or irreplaceable. At least now those reading these posts have been warned...
 
Bob it was meant as a joke I really dont see a need where I would be have to change gears on the lathe while its running. But yes I tried that with my isuzu rodeo and they wont come out of gear once in no matter what the rpms, but it took me a long time to learn our big work trucks that you have to use the clutch just for first gear and then run the low and high gears with no clutch just listening to the engine to know when to shift, down shifting was the hardest to learn on the peterbuilts cause yah have to rev em up a bit before it will slip in but im pretty good at it now.
Usually any manual transmission will gently slip out of gear if there is zero load on the gears, the engine not driving the wheels, and the wheels not driving the engine either. At that point it should slide right out of gear. To go back into gear, the gear speeds must match closely. That is how big trucks are often shifted, up or down while moving, as you noted.
 
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