The Pm-1440gt Has Landed

[mksj]

The proximity sensor has an override button which allows you to reverse the carriage once the sensor is triggered. The micro limit safety switch will engage at about 2 mm should you press the P bypass switch and the carriage goes in the wrong direction, i.e you make a mistake and it cannot be bypassed. You physically must disengage the feed and backup the carriage.

If the proximity sensor is unplugged the system will not work, a jumper wire is needed to make the connection of the proximity sensor. You can also make up a cable plug with the bypass from the brown wire connected to the white wire.

As Jbolt mentioned it is also there as a redundant safety stop should the P sensor fail, although they have a lifetime warranty and if they did fail the system it would shut down the system. The other issue has been high feed rates such as threading below 20 TPI at over 400 RPM, the P sensor will trigger but the carriage travel in 1 second exceeds the sensor trigger range of 8 mm. I am experimenting with a 12 mm sense range proximity sensor, it works well but the accuracy is a bit less because of the lower refresh rate of the sensor. Repeat accuracy has been within 0.004" as opposed to 0.0004" when threading at 450 RPM with a M16-2.0 which is around a 13 TPI. High feeds like this were not possible with a 8 mm sense range.

Safety micro limit switch is below the P sensor. When the micro limit switch is fully depressed the switch plunger must be flush with the stop face otherwise the switch will be damaged.

 

[wildo]

This is a really great threads with some awesome mods! I'm am left a little confused though: how do you actually turn the thing on? I mean- the jog toggle is momentary, right? So do you turn the lathe in fwd by pressing up or down on the jog toggle? Does momentarily pressing up or down keep the lathe on? If so, do you not have an actual jog function then? And finally, since the toggle returns to center- how are you stopping the lathe? Do you always use the e-stop button to stop the rotation?


[EDIT]-
ummmmm..... never mind. I forgot that the lathe has it's own run/off switch on the carriage! Hahaha! Clearly I am quite used to my rather modest SB lathe which has only one way to turn it off and on.


Thanks!

 

[jbolt]

Adding Cad drawings for the Marathon E470 motor mount I made. Due to manufacturing variances always measure your machine and motor to verify dimensions and clearances.

 

[jbolt]

Adding Cad drawings for the belt cover modification for use with the Marathon E470 motor. Also include modifications for recessed spider. Due to manufacturing variances always measure your machine and motor to verify dimensions and clearances.

 

[Larry42]

I think all of my equipment (factory wired) uses 24V coils on contactors. That way they can run all the limit switches on the 24V circuit and not worry about safety if a wire gets damaged. I do the same when I make new control systems for old equipment. Control transformers are small & relatively cheap. I also put a fuse block on them in case there is a short some place. Automation Direct is my go to for controls and pneumatics.

 

[Lucky Liverider]

Day 3....

The DRO is installed and working. The Z has 37.1" of travel and the X has 6.5". I ran the Z back and forth through the full travel several times to a TDI and it returns to dead nuts zero each time. Same with the X. The kit supplied universal drop leg for the Z read head mount was not usable so I made a replacement out of some 0.5" x 2" aluminum bar stock. Instead of drilling new holes on the back of the saddle I placed it under the coolant riser mounting block with longer screws. Works great. The DRO display is temporarily mounted to a piece of bar stock attached to the side of the back splash. This may change after the VFD conversion...or not.

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Cover installed. DRO display and LED light (Thanks for the light Matt)
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Whoever installed the back splash needs a refresher in measuring. The side attached to the head stock is 1-3/4" too far back compared to the tail-stock end. This left a gap that would allow debris to fall on the floor behind the machine. I re-drilled the holes an inch further in and installed a 3/4" spacer on the tail-stock side. This keeps the back as far out as possible and still able to contain debris. There is still an open gap between the ways and the motor so if that becomes a chip magnet I will add a secondary guard to cover. The back splash is made from 1/16" steel and is very stout.

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The T-nut slot for the stock tool post turned out to not have been machined parallel to the top of the compound. The T-nut I machined for the Aloris QCTP is was higher on one side than the other. My T-nut was machined within 0.001". The Slot is about 0.008" out of parallel over 2". The stock T-nut was installed and ground with the compound. If you turn the stock t-nut around it wont sit flush. I used some stainless steel shims to bring everything true and parallel when cinched tight.

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Here are a few shots of the stand. It is made from 3/16" steel with reinforcement in strategic places. It is very sturdy and rock solid without being bolted down. Matt did a good job on the specs for this one.

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Electrical for the single phase version. Nice and tidy with easy access. FYI when the machine is plunged in the transformer is powered regardless of the e-stop position so beware.

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And finally the coolant pump and reservoir. I'm not thrilled about the access from the inside. PITA the deal with. there really should be an access panel on the outside. The get the pump and reservoir out the drip funnel must be removed. The drip funnel is kind of funky and I suspect will not contain any splashing. I will see if the tray can be replaced with a hose and still allow the chip pan to pull forward.

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Almost ready to be put in service. Next up will be final leveling and some test cuts!

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jbolt,

if your factory t-nut was machined correctly, would the Aloris BXA bolt right on? I don't see a bolt and thread spec in their catalog. Buying directly from Aloris gives you the option to have the supplied T-nut machined at no costs but it would be nice to have a spare

 

[jbolt]

The Aloris uses a different size stud than the factory one so you need to use the Aloris stud and t-nut.

Sent from my SM-G955U using Tapatalk

 

[archie]

Now that the foot brake is done I started on the VFD conversion. Finding a 3HP motor that would fit was a PITA. The factory 2HP single phase and 3HP 3 phase share the same size housing. Not sure how that works but whatever. The only 3HP motor I could find with the same factory frame size was a 3600 rpm motor. The 1800 rpm motor of the same series was much longer and would not fit. I managed to find a 3HP 1800 rpm inverter duty TENV Marathon motor that is short enough but it has a larger circumference. The new motor has a 1.125" shaft vs. the 24mm factory motor so I had to get a new sheave from Gates.

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The factory motor mount would not work with the size and configuration of the new motor plus it is a pain to adjust so I fabricated a mount out of 1/2 steel plate. I basically made a large hinge. The pivot part of the hinge is made from 5/8" rod drilled out for a 5/16" hinge pin. The motor is supported/adjusted with two tie rods similar to what I did for the foot brake. Takes just a few minutes to change the belt now, seconds to adjust.

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Because of the larger diameter motor it now interferes with the belt cover so that will need to be modified. I was planning on modifying it anyway to add a spider the the rear of the spindle.

i see that is a tenv motor. how is the temperature on motor as compared to the tefc?thanks

 

[jbolt]

i see that is a tenv motor. how is the temperature on motor as compared to the tefc?thanks

It barely gets warm no matter how hard I run it.

 

[jbolt]

By request I am adding drawings for the machine base risers.

I made these from stock I had on hand. 1/2" x 2" steel bar, 2" x 2" x 1/4" steel angle and 1/2-13 all-thread. All parts are welded except the cross braces.

I chose to connect the base riser sides with a piece of 1/2" all-thread that clamps a length of angle iron as a cross brace because I could not confirm the base was flat enough to weld the cross braces.

All dimensions are for reference only. Measure your machine to verify.