On Friday 21 August 2015 06:29:51 Mark Wendt wrote:

> On Fri, Aug 21, 2015 at 3:43 AM, Gene Heskett <[email protected]> 
wrote:
> > On Friday 21 August 2015 00:35:51 Milosz K. wrote:
> >> Gene,
> >>
> >> What are your axis limits as set in the INI file?
> >
> > This is in mm's
> > gene@GO704:~/linuxcnc/configs/GO704fast$ grep LIMIT *.ini
> > X
> > MIN_LIMIT = -245.0
> > MAX_LIMIT = 245.0
> > Y
> > MIN_LIMIT = -69.0
> > MAX_LIMIT = 70.0
> > Z
> > MIN_LIMIT = -240.0
> > MAX_LIMIT = 75.0
> >
> > The file however is all in inches as a G20 is in the preamble.
> > And I have home switches, so position.txt has been disabled.
> >
> > Thanks Milosz.
>
> Gene,
>
> -240" on your Z for a min limit?  Makes for a tall column, don't it?
>
> Mark

In order for me to home it, with work on the table, the home switch is 
only a couple inches from the top of the GO704's post.  That way I don't 
crash into whatever work may be on the table when I hit the home-all 
button, or the ctrl+home keyboard combo.  Z is first in the 
HOME_SEQUENCE's.

I am about to start on a new version of the problem code, by installing 
the needed offsets into G55 & G56 & machineing each circle at the Y 
offsets needed by just switching co-ord maps. Whatever works.  Even 
without a position.txt to screw up a LinuxCNC restart so I truly do 
rehome it everytime I run it, I am convinced there is a bug of some sort 
causing the software limits, which should never be checked against 
anything but the g53 values stored during the homeing, but are being 
tripped when there is plenty of motion room left in the physical 
machines co-rds.

So I will simply do another version, using co-ord map offsets.  That will 
have the added advantage of giving me a fixed place to adjust those 
offsets. The idea is an inner circle cutout that fits the quill, with a 
larger , offset circle around it, that will give me a tab that can be 
milled thru the center to split it, sticking out of the outer circle to 
be used as a boss for the clamping bolt, and because of the offset, a 
space about 5/8" wide on the opposite side of the band to which I'll 
bolt another block hanging down so a sping loaded pin can be pushed into 
the wrenching socket in the side of the bottom of the spindle to lock it 
for tool changes.

The tool grizzy supplies is not the proper size to fit that drilling, and 
the socket isn't really deep enough, so that tool is IMO a POS and will 
damage the spindle eventually.

Grizzly wants $90 for their version, and I have several feet of the alu 
stock, 1/2" thick & 4" wide, so why not? The only thing I am missing is 
a fixed jig (or a probe to adjust the co-rds with) to hold the stock so 
I could make a few more & peddle them on fleabay, for a starting bid of 
$50 each.  To show the missus that I could make a few bucks with this 
would raise her opinion of this thing quite a bit.

That might even justify a decent vise and a 6" rotary table I can 
motorize. I have machined my cheap vices to work much better than new, 
but both jack up the work a few thou when adequately tightened.  They 
are certainly good enough to make this stuff.  Thinking out loud, I may 
make the lock pin a bolt, which when screwed in, also trips the e-stop 
with its knob. Seems like the sensible thing to do since the spindle 
drive is all steel gears. I haven't a clue what the LRA of that 1 hp pm 
motor is.  Jons servo is set to limit at about 15 amps. Rated draw is a 
hair under 10 at full load.  I am sure its Jons servo that saves the day 
when typing m3, then m4 & back to m3, such as it will see when pecking 
rigid tapping.  I have tried that at up to 2000 rpms, the turnaround is 
quick, about 1 second at 2k revs, much quicker at 300. So rigid tapping 
would appear to be quite do-able.

Because the motors flywheel/cooling fan is screwed on in the one I used 
in the lathe, I haven't tried that without some hal trickery to slow 
that turnaround down to less stressfull rates, even if it is screwed on 
with a liberal coating of red thread locker.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>

------------------------------------------------------------------------------
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users

Reply via email to