Amperage required for Mill and Lathes...

[tlmartin84]

Laying out wiring for the shop.

I was curious what type of amperage your various mills and lathes pull.

Most of the newer stuff, is not too high, the older stuff though is what I am more curious about.

I am looking for lathes that have a 36" capacity, and benchtop mills that have around 24" tables.

 

[930dreamer]

Single or three phase?

 

[Kevin54]

I can run my lathe and either the cnc mill or my Lagun mill both at the same time that the air compressor kicks on. My CNC has an air brake so I need to run air to it. I run #10 wire off of a 30 amp breaker through a phase converter for the mills, and the lathe runs off of the same breaker but not through the phase converter. So I can have the mill, the lathe, the phase converter all running at the same time. The only thing is that if the compressor kicks in (220 single phase) it will draw my lights down for a second.

 

[zkling]

Can you give an example of the specific machines you are interested in, especially the lathe. Most of the smaller capacity "bench top" machines are fractional HP up to 1hp max. A 36" between centers lathe could be anywhere from 1/2 up to 5hp (floor models), so.....

 

[tlmartin84]

My issue was the phase converter.......... And you are running 2 machines (lathe and mill) at the same time of the same 30 Amp breaker???

I'm assuming both are 220V?

So am I overkilling it running 2-30 amp feeds to each of these machines?

I want to run a dedicated 50 amp (6-3) line for my future plasma, then I have the welder, mill, and lathe..... which I yet to own and makes sizing a little more difficult.

 

[tlmartin84]

I'd like to pick up some used stuff and not knowing the sizes makes this a pain, and expensive. Ideally I'd like an old knee mill (Bridgeport), and 12" x 36" floor lathe....

 

[tlmartin84]

Kevin, how big are yours? Brands, models, etc?

And .............. you have a CNC for home use? What all do you make in it???

 

[zkling]

Went from a benchtop mill to a Bridgeport size pretty quick.

All 220v and should give you some grow room
50 amp for welder
40 amp for compressor
30 amp for lathe/mill/table saw

 

[tlmartin84]

LOL, well you know EVERYONE wants a Bridgeport............

 

[zkling]

Not me.

 

[larry_g]

http://www.engineeringtoolbox.com/electrical-motor-hp-amps-d_1455.html

Above is one example of charts to convert HP to amps, you can search out others. I think you will find that most home machines are in the 1-3 hp range. So refer to the 220v column and see what you require. If your converting to 3 phase from 220v I would suggest the 50% efficiency column to be safe.

lg
no neat sig line

 

[A_Pmech]

When I first started my shop I used a 10HP phase converter on a 60A breaker in the corner running a 30A 3-phase circuit protected by a 30A safety switch. The circuit went in a ring around the shop. I spaced twist lock receptacles in convenient locations on the ring and plugged all my machines into the circuit.

I got by fine running individual machines in the 7.5 to 10HP range with that method.

 

[justanengineer]

Both my Bport and lathe have 1 hp 3 phase motors and run off standard 110V 20 amp outlets via VFDs. Theyll actually run off 15 amp breakers but you need to set an ultra soft/slow start in the VFD or theyll trip the breaker as in my last rental home. When I bought my current house I had no desire to be in it long term, still dont, and will likely move in another 2-3 years for work. Wiring the machines for 110V IMHO maximizes resale possibilities and eliminates unnecessary wiring in the garage. I dont run multiple machine simultaneous so it works fine for me. The only 220V machines are the welders and the compressor.

 

[Kevin54]

Kevin, how big are yours? Brands, models, etc?

And .............. you have a CNC for home use? What all do you make in it???

My Lagun is a 2hp, 220/3phase mill with a 9x49 bed. My lathe is a JET 13x40 220v single phase, and my Bridgeport CNC is a 2hp, 220/3 phase. The air compressor is a 5hp, 80 gallon 220 single phase.

As far as making things on the CNC......I haven't got all of the bugs worked out yet as I just bought it last year. I'm finally down to where it runs decent, but haven't ran any real projects on it yet. Originally thought it was motor or encoder problems, had to wait on parts, custom made encoder, bought a used motor, but it was actually a broken wire in one of the wiring harnesses. I got it for a good deal, but was gullible to the fact that I never asked the guy to run an actual program, but it was running back and forth, in and out, up and down, and basically he lied to me from the start, as he never even had it programmed. I believed him because he had a decent business.

I take most of the blame for being stupid on my end on that deal and trusting him.

Aside from that, I make quite a bit of other stuff on the other machines. Nothing that I have pics of right off though, but some members will attest to the quality of my work and prices.

I also forgot to mention....my mills each have plugs, but I have one common plug that runs off of the phase converter, so I only run one mill at a time. I also have a Thompson surface grinder thati is 3 phase, but not up and running yet. Too many other irons in the fire.

 

[dcmus]

My 12x36 lathe and 9 x 49 mill both use 20 amp 220 if memory serves? They're both Shop Fox, generic Chinese but fine for my skill level.