Feedback on selecting a milling machine

My ACRA mill had several options for what type of tooling, I stayed with the R8, so ask. The factory that makes SHARP is the same one that makes ACRA which is a little cheaper than SHARP, and I am loving mine.
 
I think Sharp changes manufacturers depending on model and price whereas Acra stays with Long Chang. If buying new, it is worth watching, used not so much. Dave
 
Beckerkumm said:
I think Sharp changes manufacturers depending on model and price whereas Acra stays with Long Chang. If buying new, it is worth watching, used not so much. Dave
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Buying use... buying used... I can't afford these machines new...
 
I agree with Cathead, be very cautious about variable speed machines. The mechanism can be challenging and expensive to rebuild.
Much less to go wrong with the step pulley models. I also prefer the shorter tables like 36", less likely to bind up at the ends due to warpage/wear than the more common 42"
-Mark
 
I would look at the Sharp with DRO, 42" table. Located in Punta Gorda. Looks to be in the best shape, comes with a modern DRO and a Servo X drive, price is reasonable. Should be the LMV-42 (or Acra LCM-42) and they typically come with R8 spindle although there are other options. Would ask if everything works, and if anything is broken. Reeves drives can wear and become noisy over time, often an issue with older mills and repair can be a bit of a pain and costly. I also would check to see if they are 3 phase. Frequent stop/starts with a single phase motors, the start capacitors usually goes. You can add a VFD for not much, if using a Reeves drive, you just use the VFD more as a fixed 3 phase source for the motor and change the speed with the Reeves drive. A VFD is much cheaper and quieter than an RPC. I have the same mill, although a newer factory VFD version, they are very nice. Current version of that mill will be around 9K similar equipped.
 
If the mill hasn't been abused, I wouldn't lose too much sleep over a Reeves Drive having issues. They can be a pain but are mechanical and I have machines that are 70 years old and the Reeves is still good. Probably much better made than today's units but that system is still a very good way to get speed adjustment and maintain torque.

If you ever run across a used white colored Phase Perfect, snap it up. Same purpose as a rotary converter but quiet and the voltage stays balanced across the entire output range. They show up once in a while for under 2K and I'd argue it is worth delaying the purchase of another machine to acquire.. Dave
 
I'm a fan of Supermax mills, we bought a couple new when I was in the business. I can't fault any of the other machines, as others have said it comes down to condition and tooling. Oddly enough, I am unaware of any BP type vertical mills that are actually undesirable.

Regarding 3 phase, you have three options. Rotary phase converter, static phase converter and VFD. The phase converters are the simplest, requiring nothing beyond wiring the input and output. I have a 7.5 hp RPC and a static phase converter. My RPC creates an annoying whine and draws a lot of power whether running a machine or not. It got mothballed after the first electric bill arrived. The SPC reduces the power output of the machine you are using by about 1/3 but makes no noise and draws no power. I bought my SPC as a temporary until I got the RPC, but ended up preferring it. SPCs can be had very cheaply.

I have no experience with VFDs, but am considering them for both my lathe and mill. Both machines are belt change and I would love to have the speed control without changing belts. A VFD can provide a lot of options beyond simple 3 phase and speed control. A VFD also consumes no power, but you must have one for each machine.
 
wachuko said:
Buying use... buying used... I can't afford these machines new...
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Me either , and I wouldn't if I could . Too many nice mills around for 1/5 the cost of the new ones . Not all mills are clapped out POS . Model shops and maintenance shop mills are sometimes NEVER used as the machinists have their favorites while others sit . They are the ones I go for . ;)
 
cathead said:
If I were buying another mill and was going to buy a
VFD to run it, a step pulley machine is what I would
be most interested in. The variable speed mills have
a more complicated and I might add expensive to
repair drive system. It's hard to beat pulleys!

Another plus, they are usually less expensive than
variable speed mills.
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This

Mechanical variable speed mills day has passed.


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