[Newbie] Doall 15 Lathe

Somebody during this topic posting had said" You have been awarded a trophy.Somebody likes you". I must agree whole heartedly. The fun begins now:). Getting it cleaned up, it really is a dirty dusty mess:dread:. Clearing a spot for it in my workshop. Getting it moved in place and setup. And then getting it wired up 3 phase to single. Hopefully I can get it up and running sometime this summer. I will have to get serious about it though because as it is now my it setting in the middle of my workshop, it will be tough working around it.
LaVern
 
I love this story LaVern! I am looking forward to updates as the story continues. What a blast! How exciting wow
 
That's almost as gloaty as a Holbrook C13 for £325 (about $450...) Yours isn't as scruffy and dirty though ;)

Have fun with it - do you have 3-phase to feed it? A phase convertor is the easiest way to go, it's too good a lathe to put a single-phase motor on if it's in good shape...

Dave H. (the other one)
 
British Steel said:
That's almost as gloaty as a Holbrook C13 for £325 (about $450...) Yours isn't as scruffy and dirty though ;)

Have fun with it - do you have 3-phase to feed it? A phase convertor is the easiest way to go, it's too good a lathe to put a single-phase motor on if it's in good shape...

Dave H. (the other one)
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No I don't have 3 phase. I have been in touch with my nephew who is an electrician and does a lot of industrial wiring. He is going to come out and see what I need. My DoAll is the 1530 with a 2 speed motor. My understanding is one way of converting to run on single phase will not allow me to have the benefit of the 2 speed motor. I myself know very little about 3 phase electricity. So I asked my nephew to take a look at it and see what's needed and talk about the pros and cons of the different methods that can be used.

I guess maybe I am sounding a bit gloaty. Don't mean to. I am the one who usually misses the deal by a half hour so I am excited and pleased how it's worked out so far.
LaVern
 
LaVern said:
No I don't have 3 phase. I have been in touch with my nephew who is an electrician and does a lot of industrial wiring. He is going to come out and see what I need. My DoAll is the 1530 with a 2 speed motor. My understanding is one way of converting to run on single phase will not allow me to have the benefit of the 2 speed motor. I myself know very little about 3 phase electricity. So I asked my nephew to take a look at it and see what's needed and talk about the pros and cons of the different methods that can be used.
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I am a retired Electrical Engineer (PE). I would not even consider going with a single phase motor. My preference is a good VFD because of all the benefits they provide, but Rotating Phase Converters have been around a long time and some feel more comfortable with them. (Both have pros and cons).
 
CraigB1960 said:
I am a retired Electrical Engineer (PE). I would not even consider going with a single phase motor. My preference is a good VFD because of all the benefits they provide, but Rotating Phase Converters have been around a long time and some feel more comfortable with them. (Both have pros and cons).
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I think I read somewhere these last few days that using a VFD on a 2 speed motor will cause a loss of the 2 speeds some H.P. ? Don't know if that is right but I am having my nephew look at, advise, and hopefully install what I need. Read a lot of warnings regarding electrical safety.
 
A VFD can drive a 2-speed motor (I have one driving a 3-speed, and had to hack it to deliver 415v from 240 and do some devious programming to get it to work), but it's not at all simple to do - a rotary convertor is a lot simpler to implement, unlike a VFD (where you will need to modify ALL the lathe switchgear to operate the VFD's start/stop/reverse etc.), a rotary convertor is pretty plug-and-play, just wire / plug the lathe to the generated 3-phase and use the existing switchgear as the maker intended. Also a rotary convertor will let you buy all those tools that are cheap because they're 3-phase and most hobbyists only have at best 220v single-phase in their shops - just plug them into the convertor, away you go!
The motor in that lathe is probably 400v only, if so you may need a transformer to get the voltage it needs, an old stick welder with a dual-voltage transformer can do that pretty cheaply, then for the convertor you'd need a 400v 3-phase motor (with more horsepower than the lathe's), a couple of contactors and some run capacitors to balance the phases - your nephew may be quite capable of building it for you, efficiently and safely?

Dave H. (the other one)
 
LaVern said:
I think I read somewhere these last few days that using a VFD on a 2 speed motor will cause a loss of the 2 speeds some H.P. ? Don't know if that is right but I am having my nephew look at, advise, and hopefully install what I need. Read a lot of warnings regarding electrical safety.
Click to expand...

Your nephew will figure out, but in a nutshell running a VFD, should not matter. Depending on design of the motor it could be 2 speed with 2 windings or 2 speed with 1 winding. If 1 winding than you will have to determine the load classification: Constant Torque, Variable Torque, and Constant Horsepower. If 1 winding look at the HP rating: 1/2 HP for CT, 1/4HP for VT and 1/1 for CH.

But.....if I was hooking up a 2 speed motor, regardless of design, I would use a VFD and wire the motor for the highest speed and get rid of all those contactors and switches that go with a 2 speed setup. Than you have a variable speed motor that you can set anywhere, while being fully protected with emergency stop, variable ramp-up/down, supervised reverse, etc.
 
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