Messages

1581

General Mach Discussion / Re: Why does my router "Clonk"?

« on: June 27, 2016, 05:41:16 AM »

The current settings should be matched to the motor I think, up to but not over the motor spec. Micro-steps is usually 1000 i think but can be others, try a google on stepper motor resonance.

1582

General Mach Discussion / Re: Bridgeport Knee Mill Conversion?

« on: June 27, 2016, 05:36:25 AM »

Doubts creeping back in again on the spindle motor - 1.8kw servo seems to be the biggest i can get that runs at 3000rpm, but is it big enough? The 1.5Hp motor is 1.2kW so I was guessing at its minimum mechanical speed of 2:1 on the reeves drive it would be equivalent to 2.4kW as its about a 2:1 or 1:2 speed range on the 1440rpm motor.

However, the drive itself takes a fair lump of that power as they are not  that efficient.

So the options are still the same - build around the std motor / vfd and have possibly very vague speed settings, or throw in the 1.8kW servo and suck-it-and-see.

I guess a servo just bogs down until the drive trips on over-current if the spindle is pushed too hard?

1583

General Mach Discussion / Re: Why does my router "Clonk"?

« on: June 27, 2016, 05:26:07 AM »

WOW, that sounds rough

My only guess is resonance in the motor, I have not met this yet so have no idea how to tune it out if it is that. Some say adding mass to the motor shaft is a fix but only what I've read.

1584

General Mach Discussion / Re: Haas VF1 Conversion

« on: June 26, 2016, 04:36:26 PM »

I wish I was at your stage, but still wrestling with the mechanicals, I love the wiring and debugging part

1585

General Mach Discussion / Re: Bridgeport Knee Mill Conversion?

« on: June 26, 2016, 09:05:23 AM »

Had a chunk of 15mm plate laying about and decided to exercise my minimal CAD/CAM knowledge so made the Y axis motor mount plate.

Most impressed when it actually fitted 100% as intended

1586

General Mach Discussion / Re: Bridgeport Knee Mill Conversion?

« on: June 26, 2016, 05:52:23 AM »

Ok thanks, it makes little difference here as plenty of room in head for any width of belt, will check options before ordering.

1587

General Mach Discussion / Re: Bridgeport Knee Mill Conversion?

« on: June 25, 2016, 11:52:50 AM »

I think 44 tooth HTD8 pitch x 30mm wide belt & pulleys will handle this ok.

Decided to go full servo - budget was busted long ago so might as well carry on and fracture it some more

1588

General Mach Discussion / Re: Bridgeport Knee Mill Conversion?

« on: June 25, 2016, 08:15:15 AM »

Well i spent a few hours trying to dismantle the motor this morning but could not even get the drive disc off the end so i don't think bearing replacement is on.

It's a toss-up between living with a grumbly motor or throwing one of these in...

http://www.aliexpress.com/store/product/NEW-1-8kw-AC-Servo-Motor-and-Drive-in-6N-M-1800W-3000RPM-with-Servo-Cable/314742_2037588952.html

A 2kw would be better but none listed at present.

1589

General Mach Discussion / Re: Haas VF1 Conversion

« on: June 25, 2016, 02:50:07 AM »

I have figured out how to get the requested speed and I get the idea of slowing down to change gears.  Issue I have is how to catch a simple S200 entered into mdi.  Thats not a M03 command that I can edit in the m3 script.
  Idea would be we are running 2500 rpm on pulley one.  Threshold for gear change is 900.  A S500 shows up in mdi or in gcode program.  How do I catch that.

Have a play with SpindleSpeed.m1s macro - might do it

1590

General Mach Discussion / Re: Bridgeport Knee Mill Conversion?

« on: June 24, 2016, 04:34:07 PM »

Ok, great, i'll likely use 12mm ally then as its a good size for counter-boring bolt heads etc. The Y bracket I am sketching up at about 350mm long with the motor beneath the knee at about 5 o'clock angle.

The X axis will likely be towards the rear or below but the motor will probably have to stick out the end as most do due to it's size, this makes mounting harder but will not fit under the table as it hits the knee.