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Godzilla98
6th Apr 2009, 08:14 PM
Controlling your toy's

As discussed recently here are some pics of the control unit for my lathe

It is an Emerson Commander SK. This one is capable of running 1.5KW (2HP)

Pic 1/ The unit located on my left hand - out of the way but easily accessed.

Pic 2/ The control head. I purchase a std electrical box, some flash switches and pots and made a very functional but basic control head.

It has a "Go" or "On" push button, a "step" push button which allows you step through a pre-defined cycle.
The big red "stop" button is a locking off for safety and features instant stop with braking.

The "Forward / reverse" control is just that the and "Speed" control adjusts the speed from 0 to flat out. This motor is a 1385 RPM

Pic 3/ The control unit. It is just screwed to the wall - out of the crap and harms way, with plenty of cooling room. The unit has an inbuilt fan which fires up occaisionally.

This outfit cost me a little over $400, but I had some assistance sourcing it. Not sure what they run out at now - can find out if anyone is interested. My sparky is now in Qld.

Pic 4/ Motor - probably a bit big for this lathe but quiet and cheap!


I have the PDF of the user guide if interested. Unit has heaps of other 'stuff' it can do and can be integrated to PC ?? CNC

I know in researching this that there are a number of alternatives and I recently heard of a means to run a three phase off single phase using large capacitors - waiting on a diagram for that - other users may have already encounted this.

Basically you just need a 3 phase motor with Delta windings and that the Delta windings are 240V not 415V. Most motor rewinders can rewire for a nominal cost but there are heaps of 3 phase motors around.


Pic 5/ - Something different! Found this baby in a paddock last week Huge radial arm drill. Very old flat belt driven (Probably steam) and very weathered. Bevan & Edward made in Melb. I think Not sure if it all turns but....

Next challenge is how to lift and transport it!

brittleheart
6th Apr 2009, 10:08 PM
Hi,
Does anyone know what the motor that this control unit connects to?
Advertised in the Hercus online outlet:

http://cgi.ebay.com.au/CONTROL-CAB-SWITCHES-SPEED-CARD-FOR-X3-MILL-DRILLB_W0QQitemZ370174591935QQihZ024QQcategoryZ633QQcmdZViewItemQQ_trksidZp1742.m153.l1262?_trksid=p1742.m153.l1262

If it is a delta wound 3 phase motor, could be an interesting project.
Peter

Calm
6th Apr 2009, 10:23 PM
........................
Pic 5/ - Something different! Found this baby in a paddock last week Huge radial arm drill. Very old flat belt driven (Probably steam) and very weathered. Bevan & Edward made in Melb. I think Not sure if it all turns but....

Next challenge is how to lift and transport it!

I think you are in Melbourne - DJ is the man with the crane truck and ability to pick it up and deliver where you want - just PM him im sure he wil help if he can.

BTW nice job on th electrics.

Cheers

blackfrancis
6th Apr 2009, 11:19 PM
The VFD setup looks real nice. So you're not tempted to go out and get a much bigger pulley for the motor to give a nice top speed capability? Any trouble with chucks screwing off when you use the brake?

That radial drill looks like a major project

Peter, it says that unit is for an X3 mill. Pictures of them look like they have some sort of servo motor drive. Perhaps someone who knows about this stuff can say for sure. I don't think it's a variable frequency drive for 3 phase though???

Godzilla98
7th Apr 2009, 11:50 AM
Peter

From the photos it looks very much like the PCB found in the VFD with similar componentry indicating an VFD device or at least some form of speed control.

One would assume t would run a suitable motor.
If you had a Delta winding 3 phase it could be great !!
See if you can find out and if they any more because they could be grafted to lathe easy as.

Freight might be a killer

Blackfrancis

No probs with the chuck - I am not sure I have used the full stop at speed - I wind the speed down to zero mostly to stop - then only turn off if required becuse when the controller has "control" it is difficult to freeturn the spindle.

Aah yes the pulley - first step is to get a true chuck so I can bore a true pully - other wise there will be another wobble pulley in the bin,,,,I have a four inch waiting but my motor shaft is 15/16.

I am looking for 5" 4 jaw and need a hercus backing plate1.5" 8tpi


As for the drill - No I'm in the sunny north east - cost of transport may make it prohibitive given it may never work BUT... If they have a big tractor at that end I can mange this end - stay tuned

Thanks for the freight advice

Cheers

Ian

brittleheart
7th Apr 2009, 08:14 PM
Had a close look at an X3 mill today.
It runs a DC brush motor, so its not suitable for AC application.
I have done 4 VSD conversions to lathes and a mill with the help of an industrial sparky. I will take photos and can make some suggestions if anyone interested.
For industrial use and to keep things legal, it can be costly. Depends on what functions and quality you are happy with. I chose to use quality items, on the advise of my sparks. So far they have not been a problem.
Peter

blackfrancis
8th Apr 2009, 04:56 AM
I'd sure be interested Peter. I just want basic speed control without the frills. My knowledge on this is rather limited at the moment. I'm keen to learn more after being pointed in the right direction.

I think some good info on this subject would be of interest to quite a few people.