Hello Guest it is March 19, 2024, 04:59:58 AM

Author Topic: Bridgeport Knee Mill Conversion?  (Read 269136 times)

0 Members and 1 Guest are viewing this topic.

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #520 on: September 27, 2016, 08:46:37 AM »
There are servo drives out there that can run off single phase and are rated 3Kw, for example an Allen Bradley DSD-030 (note NOT the DSD-HV030) which I use on the big lathe. On the Z Axis I have a H4075 motor which is 9.9Nm cont and 3000rpm. so about 3.14Kw. On the  X axis I have a H4050 motor which is  about 6.6Nm cont and 4000 rpm so approx 2.8Kw.
Problem is they are scarce second hand this side of the pond and are extortionate at the other side. You can also get the older drives, DDM-030 but again rare on eBay over here.

Hood

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #521 on: September 27, 2016, 08:53:14 AM »
Thanks Hood, I think the servo idea has been passed now, will focus on what is achievable with a vfd/3hp induction/encoder setup i think.

Was a nice thought but just not worth more cost than the little servo i was looking at.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #522 on: September 27, 2016, 09:31:08 AM »
Small encouragement from CS_Labs....

With their ENC module, a vfd and encoder, activate the Pid loop in Mach3 using their settings, it will give reasonably closed-loop operation as far as speed regulation goes as well as real-time display of actual rpm on the screen :)

Sounds good to me, I have the ENC module already so thats one step less.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #523 on: September 28, 2016, 10:15:56 AM »
Parts on order, went for the Ac motor with vfd and braking resistor with encoder fitted somewhere ;)

Be good to get rid of the clattering vari-speed stuff up top at last.

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #524 on: September 28, 2016, 02:47:31 PM »
The Encoder ideally needs to be 1:1 with the spindle so if you have no gearing then on the motor would be fine, if gearing then you would really need to mount a pulley/belt setup for the encoder directly from the spindle.

Hood

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #525 on: September 28, 2016, 02:56:05 PM »
Drive is 1:1, 8mm pitch HTD belt 30mm wide

I was thinking of making a new bottom cover - the one that sits under the motor - and joining up to the motor shaft with something.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #526 on: October 01, 2016, 09:54:14 AM »
Todays lesson...
When CAM'ing a part, don't program the spot-drill to go from stock top to -2mm from stock bottom when you really wanted -2mm from stock top ;) ;) ouch!

Todays question...

I had the Scripter compile error in M3.m1s again, so the machine starts up and as it had a drill bit mounted and i was already over the hole location it happily pile-drived the stationary bit into the work:(

There seems no trigger for this error, its random, there is no error in M3, it was half way through a 6 tool job, it's always bad news and the only fix is to restart Mach3, re-home and carry on. Sometimes you can hit the E-stop in time but if its close to the part location then it usually just piles in.

Is there a setting or a way to get Mach3 to abort motion if there is a script error or indeed ANY error? It seems stupid putting the message on screen and just continuing???

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #527 on: October 01, 2016, 11:41:53 AM »
Re the script compile errors, there are a good few posts on the 'net about it, no solid answers though :(

Various versions of Mach affected, the only common response is to delete the macros folder and let Mach create a new one then copy back your custom macros, tools and offsets.

Not great and no answer as to what causes it.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #528 on: October 02, 2016, 07:24:34 AM »
Another not so great day, infact i nearly gave up. :'( 30 minute job takes over 3 hours.

Simple job - two setups, total of 5 tool changes, motor mount/adaptor plate for my new drive motor, basically a 250mm circle with 110mm hole in the middle, plus some bolt holes, tabs etc. A nice fun part to play with?

First tool/pass goes well, then the Z gets the command to home for tool change - this triggers a (soft) limit switch, right on the tool change. Reset pressed, tool changed, Z ref is now wrong, reset, pass runs ok, tool-change time - (soft) limit triggers again, same routine.

Offsets look odd but maybe correct, i haven't figured out the numbers yet - pictures below.

The screen tells me max-z is something like 220mm? A bit tricky as i only have something like 130mm to play with? Surely my Z-Max has to be Zero?

Then i start a run and as soon as it hits the first X/Y G1 line it throws an ePid fault, and again, reset, swear, go indoors and re-cam the part for a single tool in the file and it runs OK ?

Its just winding me up something terrible as I am not 'fiddling' with stuff or editing macros etc, I just went out, booted up and tried to do some work.

I have no idea what to fix or what to post up here so other can chime in but boy is it pissing me off.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #529 on: October 03, 2016, 06:16:12 AM »
Anyone?