Messages

311

Show"N"Tell ( Your Machines) / Re: South Bend Fourteen Lathe conversion

« on: March 14, 2013, 02:37:41 PM »

I'm definitely no expert and haven't slept in a Holiday Inn Express but I'll bet'cha if you can describe what's going on (or not going on) succinctly, you will get it working with the help of the great guys here.

312

General Mach Discussion / Re: What's the best starting point for a Mach3 based lathe?

« on: March 10, 2013, 12:14:49 PM »

Thanks a lot Rich.  Lotta good stuff there that'll help me a lot when I get to the point where I can understand it!

313

General Mach Discussion / Re: What's the best starting point for a Mach3 based lathe?

« on: March 09, 2013, 09:59:24 AM »

If you like the standard mill screen then you can use that if you change the file extension to .lset rather than the .set.

DOH!!  I've been doing a little bit of reading about screen mods but as usual one of your bits of advice to someone else switches on the (very dim) lightbulb over my head.  I've gathered up most of the pieces to build a small aux. milling spindle for my lathe and was dreading the screen design process to add the 3rd axis.  Starting with a mill screen should be much easier if not fully functional for my needs, thanks!

314

General Mach Discussion / CamBam & lathes?

« on: March 08, 2013, 06:52:52 PM »

Anybody on board actively using CamBam for lathe work?  I know most of you are big on Dolphin but I can't handle the price.

CamBam have a trial version but new software is so hard for my dumba$$ to learn and I don't want to invest a ton of time if it's useless.  Most of what I need to do is pretty easy stuff that I can handle with Mach wizards but I do need something that can handle internal elliptical or parabolic curves from .dxf's.

315

Show"N"Tell ( Your Machines) / Re: Denford ORAC lathe retrofit.

« on: March 06, 2013, 06:19:14 PM »

ORAC update:

I decided to add spindle reversing.  Initially got it working OK controlled from Mach with a big DPDT relay switched by one of the small relays on the B.O.B.  After advice from others, I got really worried about screwing up the G-code and frying my KB speed control by reversing directions with the spindle still spinning down so I ditched that plan.

A knowledgeable friend recommended another type of KB controller that (safely) does the reversing with onboard circuitry so off to ebay I went.  I got lucky &  found a N.I.B. KBCC-125R for $65.00 + shipping and pounced on it.  It has a more modern controller, an APRM-3 reversing module and a big dynamic braking resistor all mounted on a huge heat sink.  A very serious piece of kit!

It was way too big to fit in the enclosure so I picked up a 4x8x12” electrical box from H.D. to put it in and mounted it on the back side.  I followed KB’s recommendations & routed the control wiring in a separate conduit kept well away from mains power & the motor leads.  I also added a small 12vdc fan on the bottom with vent holes at the top to allow airflow across the heatsink fins & the resistor.  I will add some screening on the vent holes as soon as I get my hands on some.

It works GREAT.  It smoothly & quickly comes to a stop from full speed, switches direction and spins right back up to speed, no muss, no fuss.  After adjustments, the speed tracks the commands from Mach within 5 to 30 rpm from 150 to 1600 rpm in both directions.  The 30 rpm variance is in reverse.  I guess the motor timing isn’t perfectly symmetrical but hey, it’s closer than I’ll ever need!

316

General Mach Discussion / Re: spindle speed problems

« on: February 26, 2013, 09:59:12 AM »

A fellow ORAC retro-fitter, awesome!  Please post up some pics in the machines "Show n' Tell" section.  I'd love to see how you've done yours.  Mine's in there someplace.  Yours have the toolchanger?

As to your spindle, you're gonna need to close off all but one of the holes in your spindle sensor disc.  AFAIK, Mach3 will only work with one pulse per rev.  Mach4 possibly will work with more???

317

General Mach Discussion / Re: Mach3Turn Offsets?

« on: February 21, 2013, 11:34:37 AM »

You guys please keep this thread active & alive with your learned discussion & videos.  I read every word and watch every video that comes up on the subject.

Maybe by the time I get through phartin' around with the hardware on my lathe I'll have soaked up enough tool offset info by osmosis that I can get my front & back toolholder system working.  Miracles do happen....sometimes.

318

General Mach Discussion / Re: Mach3Turn Offsets?

« on: February 20, 2013, 05:41:19 PM »

maybe in about 20 or 30 years time we will have a new updated Mach3Turn

A new version of lathe, devoid of all problems...
RICH

Yabbut, then what would Hood do on those long, cold Scottish nights without us'ns to baby sit?

319

General Mach Discussion / Re: M3/M4 spindle reverse safety?

« on: February 19, 2013, 02:35:26 PM »

Well I took the pusillanimous way out.  I just copped a brand new KBCC-125R (emphasis on the R) on ebay for $65 + shipping. 

The R models do Forward-Brake-Reverse with a SPDT On-Off-On switch or Forward-Instant-Reverse with only a SPDT switch so surely I can control it safely with the C11's 2 relays.  Being a KB, it's probably bullet-proof as well....dunno 'bout FOOL-proof though.

Now I gotta start figuring where to put the thing since the APRM3 reversing module makes it almost twice as big as the KBIC-120.

Wish I'd had a friggin' clue when I started building this thing!  Oh well, there's always the next one.

320

General Mach Discussion / Re: M3/M4 spindle reverse safety?

« on: February 19, 2013, 01:19:21 PM »

Great links Brett, thanks!

...you're much better off simply using a manual reversing switch to make it really fool-proof (well, assuming the operator is not the fool....).

Hey, I resemble that remark!