View Full Version : Newbie with a lathe question

09-09-2002, 08:50 PM
I have been offered a CVA toolroom lathe complete with all tooling for $2500, it has also been converted to single phase.I know nothing about this brand other than it was made in England and what I have read at Tony's web site .Does anyone have experience with this brand of lathe and is this a reasonable price? TIA Mike

09-10-2002, 10:50 AM
Looks like a beauty. If it is in good condition, and depending on amount of tooling, it would be well worth the price.
Looks very much like a Monarch, and sounds to be comparable.
Can you inspect in person? Use Tony's inspection tips to check it out. Try to see under power if at all possible.
You don't mention bed length. Some toolroom lathes have short beds, that may be a factor in your intended use as well.

Ragarsed Raglan
09-10-2002, 11:11 AM

Having used a CVA many years ago I can only say that 'they shall not disappoint'. Only question is where you going to put her? They are incredibly heavy for the size of machine, one of the reasons they give such accuracy, better make sure your foundations can take the weight.

If it's one of the later DC motor drive machines....I see it's now single phase (and I'm assuming its single phase for America NOT the UK! - as the later will be 220-240V)...see if the original motor is available. You just might want to convert it back again to DC drive at some point.


09-10-2002, 11:29 PM
Thanks for the input guys. I went and looked the lathe over.It's a 12 1/2x 30. Tried all the speeds and feeds,they worked great.The lathe looked in very good shape so I bought it.Always wanted one,now I have one.I rented a diesel cherry picker,loaded it on a one ton flatbed truck and brought it home.This sucker is heavy.Now sitting in garage on some pieces of cold rolled. Thanks again.By the way,the guy I bought it from gave me all his tooling,so I only have to buy some coolant Mike

09-11-2002, 10:10 PM
You sneaky bugger you - and they wife has not noticed it yet? http://bbs.homeshopmachinist.net//biggrin.gif

Congrats - have fun - don't rip an arm or leg or something else off... http://bbs.homeshopmachinist.net//eek.gif

09-11-2002, 10:17 PM
Way to go on the lathe. I'm still looking for one, a 9x20 bench, due to space. How did you unload it in the garage? Curious, are the dials on that type lathe inch or metric?


09-12-2002, 12:12 AM
Thanks guys. The dials on the lathe are inch.It weighed about 3300 lbs. I rented a diesel powered fork lift with the forks mounted on an extendable boom.I was able to drive to the front of my garage and extend the boom into the garage part way. I then set it down on some pieces of 1/2 inch cold rolled and rolled it where I wanted it.Getting the cold rolled out without losing a finger was the hard part.BTW I got the three phase motor with it.It's a 575 volt motor, 4 h.p. Can I get a VFD to run that voltage with single phase?

09-12-2002, 08:52 AM
Typically you cannot run a higher output voltage then your input voltage in a VFD. There may be some that can do that, I have not come across any. So if you have 240v mains, then your output is limited to 240v. All the VFDs I have checked also only go up to 3 hp for single phase operation. 575v is Canadian standard which would mean a special order too, but then you would need to add a transformer to your input to increase the voltage to the VFD to 575.
It would be much simpler to get a new motor.

09-12-2002, 08:55 AM
Take a look at www.dealerselectric.com (http://www.dealerselectric.com) for VFDs. I think they may have some that can deal with 575V, but probably not with the input voltage you have. Worth checking, though.

09-12-2002, 11:32 AM
Hi, Madden,

A few months ago, I needed a VFD to run a 5 HP, 3 phase, 240 vlt motor. I found a brand new, 10 hp, 3 phase input/output, 240 vlt Mitsubishi FR-V220E VFD w/ 1yr warrant for about $350 on E-bay. Since I have single phase power, I asked Mitsubishi if I could derate the VFD to 5 hp w/ single phase input and still get 3 phase output. They not only told me that it could be done, they sent me detailed instructions on how to do it!

I still haven't hooked it up. I'm in the process of upgrading my power service. But the moral of the story is that you can probably get a VFD rated at 8 HP on 3 phase input, run it on 1 phase input with a 3 phase output equal to about 4 hp. HOWEVER, check with the manufacturer first to make sure this is kosher with their unit. I did have to give up some bells and whistles to have it accept 1 phase input. I hope this helps and GOOD LUCK!

John Stevenson
09-12-2002, 01:58 PM
I have one of these CVA lathe, made in 1953 and it's till in everyday use in a job shop.
Very accurate and reliable. I have had this one 17 years and the only part I have replaced is the cross slide screw and nut.
If you look carefully you will se that it's all one casting, base, bed and headstock and as RR has poined out very heavy.
One neat trick these can do is to screwcut from 1 to 82 tpi with no gaps.
They were setup for threading in development shops hence the vast number of threads. It should also have a quick return stop on the crosslide to help with threading. That little chrome screw on the side of the dial is not a locking screw.
Another trick is to place the tool at the end of a bar with the infeed set at about 1/16", start up and select both feed screw lever together and you get a nice 45 degree chamfer on the end of the bar!

John S.

09-12-2002, 11:45 PM
Russ, I rented a regular engine hoist from US Rentals to move both my mill and my lathe. Both machines are around 1,000 lbs in the form I moved them and the lift worked famousely. Dave