Advice on converting a Sharp engine lathe to CNC (Resolved)

[keithwhite]

So some background on me and my shop:

I have single phase power in my shop and currently have:

Haas VF-0 (1998) Mill(Haas controller)
Mori-Seiki SL1 lathe (Bought with a complete centroid retrofit done to it- Just got it up and running finally)

Howa 1500 engine lathe
Prototrak kneemill with sortof 2 axis cnc that I have never bothered to use. I mainly use it as a manual mill
Crossfire pro plasma table.

I have been able to figure out most issues so far with every machine I have, the two cnc machines I have are wired up to my Phase converter (10HP) and it seems to be doing the job so far.

I have an opportunity to get a sharp Engine lathe from work, for free. Its a decent lathe, but no where near as nice as the howa for a manual lathe. The controls suck, its just not a very nice lathe to run. But I thought this would be a really nice candidate for a centroid conversion. The lathe is actually bigger than the howa (8 feet between centers, 2.25 inch through bore) and uses the same D1-6 chucks that my machine already uses.

So my question is this: Would this be a worthwhile endeavor? would it be worth the cost to convert and or the Hassle VS buying another CNC lathe? The Mori is awesome and my first step into a CNC lathe, but it is very limited in size, I can effectively only run about 2 inch stock around 4-6 inches long before I run out of travel. I love the tool changer and how well it works, But I can already see I need more capacity. I do still want to keep my howa manual, But the sharp would be free to me and give me the capacity I need. It would be like a Haas TL lathe.

Would I need larger servo motors for the longer bed length?
any idea what the total estimated cost of the conversion would be? I can deal with around 4-5k in cost to get this functional and I would enjoy the
challenge, but I don't want this to turn into a money pit.
I can buy a Haas SL30 from a friend for around 10k with tooling, I am not sure if I can power the lathe, But If I am going to spend anywhere near that on this upgrade, I would just buy the haas.

I should be able to get the lathe in the next two weeks after I move the shaper and mill I just sold to make room in my shop, Any input would be awesome as I would like to get moving on it soon if it turns out to be the route I end up going. This is just my hobby shop, I don't want to spend a fortune doing this, hopefully someone with more experience in this can advise weather or not this is worth doing or not. Thank you in advance for your help!

[martyscncgarage]

You need to provide information about the current control, pictures of the machine, control cabinet, the current servo drives and their make and model, current servo motors, make and model numbers, current spindle drive etc.

With more information we can give better suggestions. Point is, we can suggest whether or not you could use the current servo motors and change encoders and go with something like All in One DC or you have to replace the servos with new AC servos, and possibly go with Acorn.

Marty

[jpmsteadi]

Keith,

The sharp is a manual lathe with 8ft between centers? That a big boy for a conversion. Just thinking briefly about the conversion, I would compare it to the value proposition of the Haas:

Haas is 10K, gets you a slant lathe with linear guides, tool turret, motorized tail stock, full enclosure, and some resale value (assuming it isn't trashed)

To convert the manual lathe you will need:
-ballscrews with nuts, angular contact bearings, etcc for both x and y (on my machine, a small mill, for three axis was about 1000 dollars for high quality stuff.
- motors, and decently powerful ones for that size lathe if you are going to be turning big pieces I imagine. (I spent about 750 bucks on three motors, but found a deal used on ebay for nice motors. Probably still not enough for that big of a machine)
- acorn controller (about 350)
-electronics cabinet
- computer
-some sort of enclosure I imagine

To me, I think the Haas is a no-brainer if you have the money to spend and need a second lathe. Just having something that is able to be sold again easily if in the future you end up not needing that much capacity or end up wanting to upgrade to a nicer lathe. A home-built conversion project will loose WAY more of its value that a used Haas.

The conversion was super fun for me, and I have learned SO much from it and wouldn't hesitate to convert another machine in the future if it made sense as a value proposition and as a fun project, so I am not trying to dissuade you from it, but just offering my perspective.

all the best
-jpm

[martyscncgarage]

I misread, I thought the Sharp was a converted machine when he said "the controls suck"
If its a manual machine, well, you are in for a long haul, and expense converting a large manual lathe to CNC.

Marty

[slodat]

You could easily spend over $5k on the conversion. What is the spindle motor HP? You'll need to think about the cost of a quality VFD for the spindle.

I would buy the Haas and get to making chips.

[keithwhite]

OK, looks like this is more expensive than I was estimating. Thank you for all the feedback, I'll just go for the haas now. Thank you again!

[keithwhite]

So I looked at the Haas lathe again today. It weighs 15k and takes a 60 amp 3 phase service. It is well worth the money, but it is something I cannot power or move easily without rigging it into the shop. I think I may take another look at the Sharp. I could take my time with it and do the conversion in steps that I can afford. In the mean time, I'd love to find a used Haas TL2/3 for the shop, The Mori is working well for smaller parts. I'd like to have the capability to do larger parts and I think the sharp would do that for me. I have converted several 3 phase lathe/mills to single phase power using VFD's, and I also have access to some decent equipment to make parts if needed. Looks most of the expense will be the servo motors and drives? I may be able to get access to a Mitsubishi CO2 laser that will be scrapped, Could I pull parts off of it to use in this conversion?

[martyscncgarage]

Or just be patient and wait for another CNC Lathe to come along...certainly if you enjoy this sort of thing, by all means move ahead. I suspect all the ballscrews, thrust bearings, mount fabrication etc will take some time, but again, if its something you like doing and the machine is in good shape.....

Good luck!
Marty

[keithwhite]

Yea, The used market seems to be pretty sparse right now. I'd love to find another lathe that is a bit larger than the one I have, unfortunately, it seems like the more I am able to do, the more I want to be able to do. I have a tendency to plan for a year or so before I do anything, Maybe in that time I'll run across a good deal on a used machine.