Newbie Questions for Metal Lathe Spindle Speed

Hi Guys,
I'm a total newbie here. I'm about to get my first metal lathe to learn to turn titanium wedding bands. I'm looking at 3 models one with variable spindle speed control, one gearbox, and one gear head.
What are the differents between a gearbox and gearhead?
Because I make different ring sizes I thought I would need to change the spindle speed alot based on recommended spindle speed for different diameter of the titanium rod. So here's another question.
For the non variable control lathe with say 6 preset speeds: 100, 260, 400, 600, 1000, 1400.
If I turn a rod with "x" diameter and recommended spindle speed is 460. Well 460 is not one of the preset spindle speed and the motor is not variable control. Do I have to change the gear, belt or both to get the recommended speed of the spindle? And how do I measure the speed to make sure it's in the correct range?
Thanks in advance!

What horsepower is the lathe, what titanium grade are you going to use, how stiff is the lathe, what inserts are you planning to cut with and what surface finish are you trying to achieve? Are all cuts cylindrical or are the lathes CNC?

Anthonytn79 said:

Hi Guys,
I'm a total newbie here. I'm about to get my first metal lathe to learn to turn titanium wedding bands. I'm looking at 3 models one with variable spindle speed control, one gearbox, and one gear head.
What are the differents between a gearbox and gearhead?
Because I make different ring sizes I thought I would need to change the spindle speed alot based on recommended spindle speed for different diameter of the titanium rod. So here's another question.
For the non variable control lathe with say 6 preset speeds: 100, 260, 400, 600, 1000, 1400.
If I turn a rod with "x" diameter and recommended spindle speed is 460. Well 460 is not one of the preset spindle speed and the motor is not variable control. Do I have to change the gear, belt or both to get the recommended speed of the spindle? And how do I measure the speed to make sure it's in the correct range?
Thanks in advance!

Click to expand...

You don't have to be dead nuts on the rpm lol...tooling would be more of a concern, and if you are just learning how to turn stuff and using ti as your first metal...I'd get a class d extinguisher too.

I don't think you have thought this through. There are much more required to use a lathe than just the lathe. It is a significant investment, especially if you are starting from scratch. If your only goal is titanium wedding bands, you would have to sell hundreds of rings before you would just break even. The least of your concerns should be spindle speeds. The difference in ring sizes would not require any change in spindle speed.

steve-l said:

I don't think you have not thought this through. There are much more required to use a lathe than just the lathe. It is a significant investment, especially if you are starting from scratch. If your only goal is titanium wedding bands, you would have to sell hundreds of rings before you would just break even. The least of your concerns should be spindle speeds. The difference in ring sizes would not require any change in spindle speed.

Click to expand...

Blokes spend that much on a new Golf Driver. Surely its not the end of the world, if he wants to piss about with a lathe, Ti and Rings?

We could just piss him off to H.S.M. But that Titanium gives us a duty of care.

Thanks for the replies guys,
A little bit about me so yall can help me further. I will try to answer all questions above.
I've been selling rings for a while now, but mostly finished (already made) gold, platnium, titanium tungsten wedding bands. I only need to sell 2-3 a day to make back for the machine in a week. And I sell wayyyy more than that currently without custom options.
- The lathe is 1HP with spindle bore 1" but I'm thinking of getting a larger bore size in case I want to turn rod 1.25-1.5 inch later for ring size 15. I don't know how stiff the lathe is I haven't bought one yet. It will be a manual lathe. I have no clue about CNC programming. I heard the stiffness of the lathe has to do with gearbox, bearing, etc. That's why I'd like to find out the diff. of gearhead and gearbox etc.
- I'm planning to expand into custom titanium rings instead of just already made rings. That way I can change the color, size of diamond, gems, width of the groove for gold silver inlay. Middle groove, offset groove etc...
- The benefit of custom is I only need to stock 1 type of ring blank instead of size 4-15 including half size (50 ring each size) and over 300 styles. I'm running out of room to get more styles. Just 2 very similar style middle groove, but 1 with 1mm groove 1 with 2mm groove I would have to fully stock all sizes and take up all my inventory space. If I can custom the groove with the lathe then I just need 1 blank...cut the groove based on customer request. Inlay with gold or platinum etc...brush or polish..ship out.
I'm planning to use grade 2 or jewelry grade titanium. I might get a grinder and use HSS once I learn how to grind and sharpen the tools as I know titanium make HSS dull fastttt. But I think I will start with carbide bit (WPMT or W something) I need to find that post and writing down from one of the members here who exclusively turning titanium.
- Yes I'm fully aware of the fire hazard working with titanium chips around. I only have to make 4-5 rings/day max and I can clean up the lathe after each ring to make sure small thin chips stay out of the way.
- I don't think I will start making a ring from a solid rod right away. That will come later, so for now I will be getting ring blanks and use the lathe to make beveled edges, grooves for inlay, brushed effects. I might get a mill to drill hole for 2-3mm diamond setting.
- Can anyone tell if the brushed effect on these rings are done with a pointy diamond shape insert and repeatedly to get the effect?


I think it's best to learn with a lathe on hand. I've been reading and reading, but without actually getting the lathe I'm not getting anywhere.

If using ring blanks, you'll need something besides (or in addition to) a chuck for workholding. A good set of mandrels or the like so you can access the surface of the ring and something else to provide access to the edges. I suppose you're already familiar with that but thought I'd bring it up anyway.

Gordon Heaton said:

If using ring blanks, you'll need something besides (or in addition to) a chuck for workholding. A good set of mandrels or the like so you can access the surface of the ring and something else to provide access to the edges. I suppose you're already familiar with that but thought I'd bring it up anyway.

Click to expand...

Yes, I will be getting expanding mandrel along with MT4, MT5 ER40 chuck and collets up to the ring size 15 depends on which lathe I end up getting.

Anthonytn79 said:

Hi Guys,
I'm a total newbie here. I'm about to get my first metal lathe to learn to turn titanium wedding bands. I'm looking at 3 models one with variable spindle speed control, one gearbox, and one gear head.
What are the differents between a gearbox and gearhead?
Because I make different ring sizes I thought I would need to change the spindle speed alot based on recommended spindle speed for different diameter of the titanium rod. So here's another question.
For the non variable control lathe with say 6 preset speeds: 100, 260, 400, 600, 1000, 1400.
If I turn a rod with "x" diameter and recommended spindle speed is 460 Well 460 is not one of the preset spindle speed and the motor is not variable control. Do I have to change the gear, belt or both to get the recommended speed of the spindle? And how do I measure the speed to make sure it's in the correct range?
Thanks in advance!

Click to expand...

Estimated spindle speed calculation: RPM = 4 x surface per Minute / dia., Surface feet per minute CRS- 60, Tool Steel -40, Brass - 80, Aluminum 200. For titanium I would use a cutting speed of 40 sfm. This is good with HSS Tool Bits. You won't have to keep changing spindle speed for the small change in diameter of wedding rings. In your example of 460 rpm step down to the nearest speed on the lathe. Check the electrical requirements for the before ordering.

Roger 08/01/2017