PM-1660TL

While I plan to add a proper disconnect switch as soon as I get time & money, I forgot to consider the E-stop as a poor man’s option for isolating the lathe motor from the potentially damaging variation in Voltage that an RPC may generate while the RPC is being started.

I wonder if there is anybody who has adopted the e-stop as the on/off button. Sounds like a good way to accelerate wear on the e-stop button.

It is, after all, an emergency stop button and not an on/off button. It seems like it would be a wise and safe choice to maintain that button in good shape by using it as directed.
 
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In response to my email inquiry to Precision Matthews regarding engaging gears, PM reminded me to never use the jog button to engage gears. Of course, they advised putting the spindle in Neutral and rotating the chuck by hand. Easy does it.
 
E Stop buttons are designed to be reliable. They are fairly inexpensive to replace if necessary.

I would just make certain the motor is not engaged, the E-stop can be used or not, but insure the motor lever is off when powering the RPC. The rest of the loads are not connected to the wild lead so the fluctuations there won't bother them.
 
AlanB said:
E Stop buttons are designed to be reliable. They are fairly inexpensive to replace if necessary.

I would just make certain the motor is not engaged, the E-stop can be used or not, but insure the motor lever is off when powering the RPC. The rest of the loads are not connected to the wild lead so the fluctuations there won't bother them.
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That is great news. Somebody would have to be pretty silly to have the lever on while starting the RPC! However, everybody makes mistakes.

Funny story. At school, there are 6 knee mills. We needed all 6 at the same time a couple of weeks ago, and the instructor couldn’t turn one on. No power. He checked the breaker and various controls. He called 2 staff members over to help him, and nobody could figure it out.

So they called in a repair guy. Understand that he drove there from another town. As soon as the repairman got there, he pressed the green button on the front of the mill (under the y-axis handwheel) and the mill started right up. None of the 3 staff members had seen that big green on/off button.

The repair guy literally solved the issue in about 3 seconds!

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erikmannie said:
While I plan to add a proper disconnect switch as soon as I get time & money, I forgot to consider the E-stop as a poor man’s option for isolating the lathe motor from the potentially damaging variation in Voltage that an RPC may generate while the RPC is being started.
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Why would you want to spend money rigging a disconnect switch to your RPC? The power receptacle you have is the disconnect. You would only need that with hard wiring the lathe to the RPC.

The voltage float on the manufactured leg should pull down to line voltage as soon as it starts flowing power. I don't think you will hurt anything. Besides, you bought the deluxe fancy most super luxury electronic model RPC that American Rotary offers. It's got all kinds of protection built in that my base model doesn't. In other words, you already spent the extra money for clean power, don't spend more on components that are redundant and unnecessary.
 
My lathe only has an emergency switch.bit is to be used for on off control.
 
Agree with Pontiac428, don't worry about it, the RPC is your power disconnect as the lathe is the only machine attached to it. Also most machines have a power relay or contactor which prevents the machine from running unless the run command or direction switch is in the stop position. If the spindle switch was in the for/rev position on start up the machine would not start. If the power were to drop out, you press the E-Stop or apply the foot brake, the power latch releases and prevents restarting until it is reset in the stop position. VFD's should be used with a similar system to prevent starting, one reason why it is a bad idea to directly connect the run command inputs directly to spindle switch, they should always be wired with some form of power interlock to prevent machine restart whether it is power loss, E-Stop, braking, or any other safety interlock switch. One always thinks it will not happen to you, but one can be easily distracted and forget. Seems to happen much more frequently these days as I get older.

As far as E-Stops, they are just like any other switch and rated for numerous cycles should you want to use it when changing chucks or whatever. Decent switches last decades of repeated use, not something I would worry about.
 
So I made my first thing today with the lathe. It is a steel paper clip holder that I gave to my wife.

It involved facing, turning, chamfering, MT4 drill chuck, MT3 & MT4 tapered shank drills, and a boring bar.

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Not surprisingly, the lathe is a workhorse. Absolutely zero issues. I was taking cuts in the mild steel up to .075” and it just ate it up. Changing gears was effortless.

Sometimes (e.g. turning) my chips weren’t breaking.

The lathe is more quiet than I could have anticipated.
 
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