I have as my first lathe, a seig C0. Although I don't have a great amount of knowledgeable on the intricate workings of lathes such as these, I can definitely find faults, which usually only need a little altering to be fixed.
My Problems so far:
1.)If the work piece is threaded, the chuck will not hold it accurately
2.)On smooth pieces made of stronger materials(steel) The item will untighten itself eventually from the chuck due to the friction.
If anyone could give me advice on how to fix these problems I would greatly appreciate it, or other tips on how to improve my lathes performance or accuracy.
I have already tuned the electronics for better torque at lower speeds and am planning a home-made milling attachment that I can clamp into the tool post. Most of my inspiration comes from here :http://varmintal.net/alath.htm, Its just a case of adapting it for my lathe instead.
Sieg C0
- jackssmirkingrevenge
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No self centering chuck will hold a threaded section in a lathe accurately...Alster370 wrote:1.)If the work piece is threaded, the chuck will not hold it accurately
This could be an indicator that you're trying to take away too much material at a time, making deeper cuts than the lathe can take. Try shallower cuts.2.)On smooth pieces made of stronger materials(steel) The item will untighten itself eventually from the chuck due to the friction.
hectmarr wrote:You have to make many weapons, because this field is long and short life
Really? I never knew that. Its probably because the threads are consistent all the way round the work-piece, and thus I thought it wouldn't be a problem. Its fine with things like shrader valves, but brass fittings are a disaster in comparison.No self centering chuck will hold a threaded section in a lathe accurately...
Its only with steel really, you have to go really slow, its not as bad now with the modified electronics but I tend to stick with aluminium or brass anyway. No real need to use steel.This could be an indicator that you're trying to take away too much material at a time, making deeper cuts than the lathe can take. Try shallower cuts.
Il see If I can get a better quality chuck, its just hard to find one that fits my lathe.
Also would the quality of the fit in the lathe chuck also be down to how round the work-piece actually is? Im guessing so.
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Threads are rarely perfectly concentric with the part, besides they offer minimal contact area and are easily crushed by the chuck.Alster370 wrote:Really? I never knew that. Its probably because the threads are consistent all the way round the work-piece, and thus I thought it wouldn't be a problem. Its fine with things like shrader valves, but brass fittings are a disaster in comparison.
.Its only with steel really, you have to go really slow, its not as bad now with the modified electronics but I tend to stick with aluminium or brass anyway. No real need to use steel
Again, if you're fine with softer materials then the issue is probably that you're trying to remove too much material at once. Remeber you can't make the same depth of cut in steel than what works with brass and aluminium.
A bad chuck obviously doesn't help but I doubt this is the issue.Il see If I can get a better quality chuck, its just hard to find one that fits my lathe.
It is a reflection of it but ideally you should plan your cuts in such a way that you have to do as few chuck changes as possible. If you look at the "dimply" pengun cutting plan you'll see that LeMaudit was careful with this.Also would the quality of the fit in the lathe chuck also be down to how round the work-piece actually is? Im guessing so.
hectmarr wrote:You have to make many weapons, because this field is long and short life
Brass fittings are a disaster in comparison because there's typically hardly any length to hold them on - the threads are tapered pipe threads and thus can't be held by the chuck, and the body doesn't tend to have long flat sections.
A self-centring chuck can grip threaded sections just fine - I hold pieces of 3/4" and 1" threaded rod in my self-centring 3-jaw chuck regularly with no inaccuracies in the finished parts that I can measure (down to 0.001", at least). Brass would cause problems due, as JSR mentioned, to the softness of the material and subsequent crushing of the threads. It should work just fine with any steel over 600MPa tensile strength, possibly even less.
A self-centring chuck can grip threaded sections just fine - I hold pieces of 3/4" and 1" threaded rod in my self-centring 3-jaw chuck regularly with no inaccuracies in the finished parts that I can measure (down to 0.001", at least). Brass would cause problems due, as JSR mentioned, to the softness of the material and subsequent crushing of the threads. It should work just fine with any steel over 600MPa tensile strength, possibly even less.
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If you have a straight coupling, we often chuck up the coupler, thread in the part you want to modify, do your deed and then remove it from the coupling. No damaged threads, good concentricity if the chuck and coupling run true. You want to find barstock turned couplings, not the cheap cast ones. Those will not run concentric.Alster370 wrote:: Its fine with things like shrader valves, but brass fittings are a disaster in comparison.
USGF
In the end its probably not capable of what I thought. I visioned it being able to cut 2" steel pistons for steam engines and the like. . Il see if axe minster will take it back for a reasonable price, then il save up for a proxxon lathe or something.
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You probably could, just veeeeeeerrryyyy slllooooooowwwwwllllyyyyyyyyyyyyyyyyyy
hectmarr wrote:You have to make many weapons, because this field is long and short life
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The Sherline is a miniature lathe and will also cut veeeeeeerrryyyy slllooooooowwwwwllllyyyyyyyyyyyyyyyyyy, which means the part will veeeeeeerrryyyy expeeeensssiiivveeee
hectmarr wrote:You have to make many weapons, because this field is long and short life
you should just be patient and get to know your machine, Ive seen some incredible impressive stuff made on those lathes. Dont expect perfection, look at every project as a learning experience.
Patience is a virtue, get it if you can, seldom in a women, never in a man.