This is a nice rundown on how to convert an emco compact 5 lathe by Art Fenerty (he wrote Mach 3):
Just to kick in on costing of such a project ( having converted my emco PC5 last year. This isnt a plug for my software, I retired over a year ago from Artsoft, just info for those interested in such a conversion. )
My costs were..
Motor drivers, about 100.00 each ( 2 required. ), I used some I had from ebay that I got for about 50.00 each, prices vary, but I used 10uStep controllers @ 3amps, 24 volt. Gecko's work great, as will almost any microstep driver.)
Motors ( you can use the ones currently on a pc5, but they are very weak, or mine were anyway. You couldnt even feel the torque detents as you rotated them without power. 500oz inch ( approx) cost me about 50.00 each , but you dont really need that power. ( though its nice to have ). My power more than tripled on the axis, they cannot be stopped by hand at this point, and they are much faster.
Power supply ( the one in the emco can be used, no need for an additional one. You can tap the original power supply for 24 volts for motor drives, and the 110volts for the breakout board power. )
I also added a breakout board for interfacing. The breakout board from pmdx.com fits well in the spot where the original
emco pc com board fits in the machine. Cost approx $129.00 US. The mach3 web based form has photos of the conversion I did,
everythign fits well int he Emco casing and made my pc5 a much more usefull machine.
I also added a sensor for threading, and put a bolt in one of the original slots to trigger the sensor for speed and threading. Mouser electronics 653-ee-sb5v is the sensor I used. About $20.00 for that.
Of course I didnt have to pay for the software. :-)
The emco works very well now, has no file length limitations, and lazyturn generates code that runs pretty well if you have nothing else available. ( free from the mach3 web forum till I end up adding a final finish pass. ). The only possible dodgy part is the
threading. While threading short threads works well, after a couple inches of thread there is a bit of wander that makes the thread imperfect, though nuts do spin on with no binding. This is the result of single pulse per rev threading. Still being worked on slowly, but seems to work well for most threaders, depends on the pc and sensor configuration and setting as to how well it works.
So my total cost was about 350.00US or so ( somewhere about 175 EU ) , adding software would make it about 300EU for a complete conversion.
The same conversion would allow EMC or other software to run the lathe. If one used an encoder for the spindle EMC woudl do perfect threading on it, or if one can figure out the original sensor in the pc5 to feed the software. ( I never could get mine working but it may have been defective from the start, I never used it prior to converting, so I just tore it out and replaced it with my 20.00 sensor..)
Alternately, instead of a breakout baord a smoothstepper device, USB based could be used, the smoothstepper is also known for perfect threads. All I can tell you for sure is the upgrade makes the lathe run much better than stock, much more powerfull, faster, and more reliable. Much depends on what you use it for of course.
Thanks,
Art
And his continuation of the same post:
>>I searched around: is this the thread you mean on your conversion?
http://www.machsupport.com/forum/index.php/topic,214.0.html
Yup, thats the thread.
Wiring isnt as bad as it looks. Where you see I added a pmdx breakout board, is where the emco put their pc interface card. You just rip that out entirely. ( if you have the same machine I do.. ). Your new motor drivers wire directly to the pmdx board, so between the docs for the drivers and the docs for the pmdx, all the wiring is described. Now I added 2 drivers and a pmdx, and 2 motors, the motors wire directly to the drivers ( real easy to wire the motors.. ) , and the pmdx board simply gets a printer port cable which I wired to the pc printer port plug on the back of my emco.. and then it wires to the drivers.. ( step/direction and com ) so 3 wires to each driver from the breakout board. I put 2 7 amp drivers and a PMDX in the same area.. they all went in just fine and with little effort. Chinese drivers or geckos all run about 120.00 I think for pretty high current drivers.
As to the power supply, yell if you like when you get there, its easy to find the 24volt spot on the emco supply. Lots of current available so no extra supply is necessary at least on the PC5 version of the Emco, those two points on the emco ( 24vdc and common) wire to each of the drivers to supply power to them, the pmdx just gets a tap to the 120vac line inside. Again, pretty easy.
Thats it, no other wires really need to be done unless you want threading.. the sensor can be a bit of a bitch to wire if you dont do electronics, but again, yell when you get there, its only 3 wires to the sensor from the breakout board.. and then I put a screw in one of the slots of the slotted wheel, the sensor see's it on every spin. The sensor bolts in the same bolt holes the old emco sensor did as I recall. I can take better pics if you get to that stage. But you can cut fine without the threading sensor. ( I dont cut threads usually..). If your firend can get that sensor that comes with the Emco running, then even better as I do have a special plugin that will use an index slot and multislot timing pulses for threading. Tests show it works well, but there is a wandering after an inch or two. Still holds nuts fine, but with Mach3 dont expect Boeing quality threads unless you use a smoothstepper.. its simply a limitation
of running from Windows. On the bright side, for those that need perfect threads, this described upgrade isnt just to make the emco Mach3 compatible, its also EMC compatable at that point, so if you like linux, you can run EMC as well. ) or pretty much any other step/direction controller. Steve Stallings, the pmdx inventor is an EMC group member and pretty knowledgeable about such things, Im sure many could help you get that up and running.
By the way, the new motors simply bolted in the same spots the old ones did, no work required at all.. you just wire the 4 wires from the motors to the drivers.. pretty easy.. Any basic electronics person will find it painless to do such a job.. ( and many people who know only about basic dc wiring..). Ill post Mach3 settings for the emco if anyone wants them.. it configures pretty easy and runs real well. No limit on file size at all.
Just my opinion, but if one is to upgrade an emco, Id really recommend going this route simply because it makes it compatable
with pretty much any controller that will send step/direction commands. The future will probably bring about things like SCurve controllers, ( which smooth out motion quite nicely), or other advances in technology which , if you go proprietary you wont be able to take advantage of. We all know how long these lathes last.. pretty much forever, so having a standard type of control has its advantages. ( Emco's also seem to sell for more if they are step/dir controlled thus allowing a new owner to pick their favorite software. ). Price wise, it seems if anything quite a bit cheaper to go this route, and then its done and standard, but thats just my opinion.
I usually dont kick in on such discussions as some may feel Im pushing for Mach3 to be used, and since I wrote it Im obviously biased,but I am retired.. I only work on things like future control code these days. So that having been said, you should probably ask as many groups as you can what your best plan would be. Ive never used WelTurn , the specs dont appear to be shown real well so I cant tell you max speed vs EMC or Mach3. At about 900.00US it seems pricey to me,specially if you have to then add new motors, complete conversion to step/direction is about 300.00 to 400.00US if you stick with your emco motors, I just found my emco motors so slow they drove me nuts. Max speed on my machine is set for 554 mm/minute, I could go quite a bit faster, but at 554 I never lose steps unless I jam into material. ( In fact the carriage would snap my hand off if I tried to stop it..), acceleration is set to 91mm/sec^2 and standard setting is 2000steps/mm. ( because I have it set to a high uStep setting, which is nice if your drivers support that. ). I tend to limit my speeds because using max speed rates on something like an Emco does stress it too much, but 550mm/sec seems very doable, and my lathe has no trouble with it at all.
At 2000steps/mm, Mach3's lowest kernal speed of 25Khz can do 720mm/min max, higher kernal speeds could double that quite easily if your motors can handle it, but I dont suspect an Emco can handle a meter a minute. My motors were advertised on Ebay for 750oz in, (Deep Groove) but I dont really believe it, I thing they are 500oz in or less, but I have to admit they are very powerfull, orders of magnitude above the steppers that came with my emco, the difference is not only audible, but amazing and very powerfull, the original motors I could easily stop with one hand, I would'nt recommend anyone trying to stop these puppies with their hands..not if they like having hands. :-)
My only problem is that my lathe has the AC motor driven spindle , which makes it quite low torque, my buddies emco ( You can see Brians on the group forum somewhere as well ) has the DC motor spindle, and Ive seen him do 1/4" of steel in one pass ,
(in fact theres a video somewhere showing it do that at a pretty high feedrate. Perhaps emco's with dc spindle can all do that, I only know the few Ive worked on). To me thats a pretty high rate of speed for 1/4" in one pass. No possible way my spindle could do that, I limit to 1mm per pass or less usually, but since feedrate is quite fast it doesnt seem an issue to me. I cant see any posting of welturn max speeds or step rates on their site, perhaps someone can post their experience in terms of speed and at which point they start to lose steps. Any comparison would be interesting to those considering updating hardware or software.
The welturn software does seem very nice to use from what I can see though, and any software is an upgrade from the original dos version of emco IMO , it seems pretty limiting and pretty non-standard in its Gcodes. CNC is all about standards what with the CAM packages available. Each person has their own requirments though, so check out every option as thoroughly as you can before you make a decision.
Again, this is all just my opinion, I know of many emco's that run Mach3, and several that run EMC, all seem pretty happy. Its not
a conversion project that should scare anyone with $400.00 or so to burn.. took about 3 hours to do mine, of course it may take
longer if your not used to cnc wiring, but its not brain science and very little wiring really needs to be done. Threading seems the only real issue, there are several ways to do it, and performance there will vary with software, methodology, sensor and experience.
While I think of it, the other issue you may want to think about is an auto tool turret if you have one, ( I dont ), Mach, and EMC can be configured for it, the pmdx interface board has lots of spare outputs when used with a lathe, and macro's can be written to
run it, but I havent done any for myself. From what Ive heard when I did support they just used a timed macro to run the motor, wait for a switch to hit, then run backwards for a couple seconds to jam it into position. You can also do things like add lights, blinking indicators that job is complete, relays for various optional functions.. all advanced topics if you do go that route... the various support groups are pretty good with information on such things.
Hope these thoughts help, sorry for the verbosity.
Thanks,
Art
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