Hi Gene, > Thats great John. But I haven't noted a ready supply of such speedy parts > being used on the boards we CAN buy, with the exception of cnc4pc's C1G > rev 4 board which has been discoed as it was about 85 bucks. It also had > enough tally leds to light the room with. handy for trouble-shooting > too. But cnc4pc no longer makes an equivalent bob, dammit.
I've been chatting with Arturo Duncan at CNC4PC and he's been very supportive on what I've been doing for my friends CNC system. Haven't needed another BoB for a number of years so I don't really know what is out there now. And as I showed with the schematic, I have the background to be able to make my own custom interface boards so it's not a big deal. I make what I need now because PC boards from China are so cheap. > > > Same with the spindle. The large cast iron single phase AC 2HP 220VAC > > motor had quite the hum when it was turning. The much smaller 1.8kW > > AC Servo is so much quieter and variable speed. I looked into > > getting a three phase motor for it and a VFD. The Bergerda > > combination ended up being cheaper. But I did have to cast and > > machine my own pulleys. Now the noisiest part of the spindle is the > > rattling of the spline inside the drive part of the quill. > > And thats probably created by the servo's response to quantization noise > causing motor speed variations that use up the slack. All of that went > away when I moved from a 274 edge optical encoder on the spindle, to a > 1000 line on the rear of the motor, my scale for the spindle in the ini > file is now a bit over 7000 in high gear, and something north of 14k in > low gear. And below 400 revs, its so quiet I have to look at the tool to > see if its spinning. The index however, still comes from the spindle. In my case it's poor quality on the quill/spline interface. The spindle gets a push from the splines and takes up the space until it hits the back of the next spline, bounces off and then rattles back. If I grab the spindle and load it with my hand ever so slightly the thing is dead quiet. The outside driving part is held in bearings and has a cone shaped profile at the top. The driving pulley from the motor is also tapered and a nut with a locking key holds it together. I would have to create a different drive system with perhaps a tighter inner spline or else create a new quill with a tighter outer spline. I'll send you a few 400K JPG off list. But as a friend said to me the other day. All this iron that comes from China is for the most part meant for repair and one_of manual construction. To bring it up to HAAS standards requires a totally different approach in some areas. Like not even having a quill for example. On one forum the guy converting to CNC the same series of mill said if he were to do it again he'd replace the Knee dovetailed connection with linear bearings. I'm not about to go that far. But his approach to how he moved the new upgraded ball screw for the knee is nice but would require a complete redesign of where I have my motors. John _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
