Re: Emco Mentor Mill conversion
Quote:
Originally Posted by
Swarfing
Looking at the size of the machine i think the DC motor will do you fine. Mine will be running with only 1HP motor and that is more than enough for my needs.
Hi Swarfing, you posted the same time as me so missed your reply. yeah think the DC will be fine for this little mill but I was just trying to work out which would be best. Didnt what to spend time making mounts etc if the ac motor on vfd would be as good, it seems that the DC wins on low rpm to torqure ratio which is mainly what I need for this machine.
The sad thing is i need to get the ac motor working to make the bits to convert to dc, that is providing the spndle is ok.
Quote:
Sounds like your most of the way there then. Just need an appropriate controller and your away :-)
I was hoping to cannibalise the motor controller from the tread mill and control it with a Adruino.
Re: Emco Mentor Mill conversion
That DC motor is it a 90v or 180v by the way?
Re: Emco Mentor Mill conversion
just opened it up and the motor is 180v and 4800rpm so a little slower than I was hoping for. Driver board looks quite compact and control panel is fed from one muiti core wire so shouldn't be to difficult to hack the speed commands.
On the down side it is 10mm to big (diameter) to mount on the existing motor plate so to use that motor I will have to make a new mount and move the motor position over to clear the top of the quill. Looks like I'm going to have to have a go at rewiring the AC motor for 240v and fire up the vfd.
Re: Emco Mentor Mill conversion
Go for it, at the end of the day your other options are to spend some money. If i does not work...then just spend some money :-)
2 Attachment(s)
Re: Emco Mentor Mill conversion
finally found time to rewire the motor and it was embarrassingly easy, don't know why I was so worried about doing it. Coils measured 50 ohms on their own so in delta config you basically have two coils in series which are also connected in parallel to the 3rd coil, so if I have it correct then that gives 100 ohm and 50 ohm in parallel which is 33.3 ohms. tested each pair of wires and always got 33.3 ohms so hopefully I have got it right.
Attachment 8715
Also worked out how to set up the vfd, connected a forward/reverse switch and a speed pot. tested it on a another motor and all works fine. so hope fully tomorrow I can rebuild the motor and see if it works.
Attachment 8716
Re: Emco Mentor Mill conversion
Well done Ross:encouragement:
Re: Emco Mentor Mill conversion
ta, its good to get something done rather than just talking about it. :hopelessness: onwards and up wards.........you never know I might have a working mill by the weekend.:toot:
Re: Emco Mentor Mill conversion
Problem 1 and 2 solved. Motor works fine on 240v with the vfd and got the gearbox fixed so all 4 speeds are working. :yahoo:
I wasnt going to bother fixing the gearbox as the vfd would have taken care of the speed control but unfortunately though the 1 speed that worked was the slowest (350rpm ish). The previous owner had some replacement gears made but they didn't quite match the gear profile so I had to file them down, not ideal but needs must and at least I can test the rest of the machine.
A BIG THANK YOU to all that have help sort his especially Geoffery, M-C and Swarfing, cheers guys :beer::beer: I know most of the info is somewhere on the net but to have you point me in right direction is great.
Re: Emco Mentor Mill conversion
Nice one, put it this way once the machine is up and running you can make the bits you need to covert the head later if need be. Not sure what your box is like but most are very noisy which is another good reason to dump it. Get yourself a gear cutter and you can remake them as well if you wanted to.
Re: Emco Mentor Mill conversion
Well done Ross, I thought you had a pretty good chance of running that motor on 240V, and am glad you stuck with it, but filing the gears to make it fit - WOW. Congratulations. G.