# Pm1340gt Is Up And Running :-)



## Wood&Metal (Sep 24, 2015)

IT WORKS!! J

Thanks to a lot of help and advice from folks on this forum, my PM1340GT is up and running. Based on comments and recommendations from Matt at Quality Tools as well as members of this forum I decided to go with the 3-Phase motor and VFD solution.  I have to send out a huge Thank You to Mark Jacobs (MKSJ) for his exceptional support and detailed schematics and instructions for implementing a VFD solution.  Mark was kind enough to offer me the option of purchasing one of his custom VFD wiring solutions and I have to say I am ecstatic with turn-key solution.  I want to publicly thank Mark for his patience and willingness to answer all my questions and inquires with detailed and in-depth answers often including schematics and detailed instructions.  Thank yous also go out to all the folks on this forum that respond quickly and never fail to come up with answers to even the most basic of questions.

Here are a few pics of the new lathe with close-ups of the upgraded features.

The new lathe parked new lathe, parked next to existing PM923PDF. (hey Airwolf, check out that shelf above lathe ;-)






Close up of proximity sensor as well as new switches on control panel.






VFD installed in enclosure mounted on left end of lathe stand, notice shut-off switch on front of enclosure.






New control box with replaced relays and controls.






Additional views.











Now I just need to figure out how to use this awesome new toy......


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## dave2176 (Sep 24, 2015)

Congratulations. Those are great machines.


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## J Bennett (Sep 24, 2015)

Wood&Metal,

Congratulations on your new set up.
Mark is assisting with my VFD setup now. Should have in about 3 weeks.

James


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## qualitymachinetools (Sep 24, 2015)

Looking Great!


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## AirWolf (Sep 25, 2015)

Wood&Metal said:


> (hey Airwolf, check out that shelf above lathe ;-)



Nice set-up and great photos!  

And Yes! That is far safer looking shelf now... would have hated to see photos of the "unintended consequences" of the prior shelf failing and dumping everything onto a spinning project... not to mention the bed ways themselves!

Hopefully my 1340 will be up and running in a few weeks. Only get a couple of hours each weekend to work on it.


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## mattthemuppet2 (Sep 25, 2015)

is that a hall effect feed switch on the ways? any more info? I'm guessing it ties in to the VFD for threading or cutting to a shoulder, but I've never seen one before - I'd be very interested in knowing more about it.


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## Wood&Metal (Sep 25, 2015)

J Bennett said:


> Wood&Metal,
> 
> Congratulations on your new set up.
> Mark is assisting with my VFD setup now. Should have in about 3 weeks.
> ...


You will LOVE the system Mark builds.  He provides excellent instructions that make it a piece of cake to install.


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## AirWolf (Sep 25, 2015)

mattthemuppet said:


> is that a hall effect feed switch on the ways?



Proximity switch to stop the lathe at predetermined spot - It is built by Mark Jacobs (MKSJ)


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## Wood&Metal (Sep 25, 2015)

I assume your referring to the proximity switch attached to the micro-stop just below the chuck. It is a safety stop proximity device designed and built by Mark Jacobs (MKSJ). It will shut down the machine if the carriage comes too close to the switch. I'm sure Mark can provide tons of details. I think it's a great addition to the lathe!!


Sent from my iPhone using Tapatalk


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## mattthemuppet2 (Sep 26, 2015)

ooh, that's really cool. So more of a "don't crash into the chuck" thing than an auto feed stop? I wonder if the repeatibility of the magnet/ switch is enough to use it as a feed stop, like those half-nut kick out devices some members have made on here.


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## mksj (Sep 26, 2015)

The proximity sensor has a repeatability of better than 0.001" if the speed/feed parameters stay the same, in most cases you are looking at 0.0004". This is even with fairly high feed rates and chuck speeds. It requires a VFD with electronic braking on the order of a second or less (requires a braking resistor with VFD external braking circuitry) , so stops happen quickly and predictably.  This would not be possible to these tolerances with a mechanical system, or mechanical electrical system such as a mechanical stop switch, also you do not have the braking. The advantage of the mechanical stop,feed stop is that it stops the carriage at the same position in the Y axis, and is not affected by feed or speed, they disengage the feed system. An electrical stop in this type of setting, needs to be readjusted for any major change in the feed or speed, as the momentum in the system will change the stop point to some degree. Think of it as the travel distance feed system relative to the rotations of the chuck over 1 second. The maximum variation I could achieve in my system was about 0.050" more travel between a snails rate feed/speed and stupidly high feed/RPM rates.

The proximity sensor is an interesting concept, but like anything electronic, they can fail (usually due to damage) or you can have operator error. I do find it an additional safety factor when turning or threading to a fixed position, and makes it much less stressful of disengaging the feed at just the right time.  The addition of the secondary "Kill Switch" which kicks in after the proximity stop is a real plus, I thank one of the forum members for suggesting the idea.  Anyone with a VFD lathe system, should consider as a minimum adding a snap/end of travel switch which acts as an E stop if a particular travel limit is reached (same as feed systems). Wire it in just after your E-Stop, just beware that without a  reset relay the system will activate when you release the switch.

Another point to consider with either system, is that the stop position is based on the carriage, not the tip of your cutter in the Y axis. So if your tool post position is changed, and it is not perpendicular to the cutting surface, the stop position of the tip changes with the tool post position. When cutting the diameter using a stop system, I use the cross slide, so there is no change in the cutting tip Y position. When cutting a thread, the cross slide is locked, I "0 or record the distance" my DRO Y axis at the position the cutting tip is to end with the tool post advanced to the depth of the final thread cut in the relief. Remember if you cut at a 30 degree angle the stop position changes as you advance your cutting tip. I then back out the tool post slide and set the electronic/mechanical stop position based on the DRO reading. I verify this with an extra pass.  Then do my scratch pass for threading, and "0" the dial on the tool post slide, then get to cutting the thread in sequential passes only using the too post slide. You have the option to either disengage the half-nut and manually back up the carriage on each pass or electronically reversing the carriage by pressing the electronic bypass (proximity) switch and reversing the spindle. That latter is required for metric threads.

I will probably build another batch of the P sensor stop systems (two will go with complete systems), the new design works well but is a PTA to make . I appreciate forum members comments on some of the systems I have built, as they have evolved with newer versions. I hope to post some more build schematics, with detailed parts lists for the VFD low voltage systems for others in a couple of weeks, time permitting.  The revised design should work with any lathe and any VFD that has at least 5 inputs, and has circuity for an external braking resistors (which excludes most Chinese eBay VFD sellers). The last issue has been using the stock work light 24V 50W halogen bulb that comes with some machines, was not happy with anything less than a 100W power supply. I have switched mine out to an LED bulb, otherwise for any of these systems using the stock bulb, probably go with the recommended 100W DC power supply in my schematics (only one that fits).


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## Firestopper (Sep 26, 2015)

I have the privilege of knowing Mark Jacobs as we live in the same city. Mark not only is generous but a real smart gentleman. I too reached out to him with a uncommon issue of adding a VFD to a plate roller that is powered by a RPC. He not only helped me with the VFD, but redesigned the electronics and added much needed safety upgrades. His wiring is impeccable and second to none.   The plate roller has never worked as good as it does after Mark's attention, and the man can cook too!
Nice lathe, I'm sure you'll enjoy the new upgrades!


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## Bamban (Sep 27, 2015)

Mark helped me with my projects, first the 1236 and then the 1024, both machines are running on VFD control boxes Mark created.

http://www.hobby-machinist.com/threads/acer-trump-1236-vfd-conversion.32910/#post-278254


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## Dman1114 (Sep 27, 2015)

Mark Is the MAN!!!!


He took good care of me and Dumbed it down so i could understand....  

I haven't had a single problem since i finished it....  Best upgrade ever!!!!

http://www.hobby-machinist.com/threads/g4003g-going-3-ph-vfd.34549/


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