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Can you find any specs on the motor that drives the CVT adjuster? Maybe even a pic. of its nameplate. I suspect something should be available for it. Using a VFD for speed control a person can gain some low end torque using closed loop speed feedback and PID, but the CVT on my Wilton mill certainly has a lot more low speed torque than I was able get with just a vfd on another project.

Hi all,

I've just pushed MetalHeadCAM v0.3.0 to cam.metalheadcnc.com. I'd love to hear any and all feedback you have.

Just import a DXF file, then click the Add button in the operations panel. After that you should be able to simulate and export Gcode.

Since the last release:
- Much improved performance
- Added spot operations

I'm still not maintaining backwards compatibility, so if you've tried it before be sure to go to the hamburger menu in the top left corner > Settings > click Reset Application before use.

 

I will add that, with the invention of "servos with a step/dir interface", linuxcnc has lost the ability to shut off the servo power yet still keep track of where the machine *is* for when power is restored

My thinking is that once you have the machine dialed in you will never get this error.

Agreed; I wired my servos this way for when I get a hard crash.  the "fault" includes following errors in the clearpaths, and I really want the machine to stop and release the servos and spin down the spindle.  The hard crash might be a fleshy crash.  I realized the servos were going to lose position, added the VOLATILE_HOME, and discovered this bug...

Hi.
I have mini pc that i tried to install linuxcnc ( latest version) but horrible latency above 100000.
So i put Debian 12 and install kernal RTai 5.4.258 and linux cnc 2.9.3.
All is good, latency test is like max 24000 with default settings in the bios ( remove everything from the bios i got about 16000 after 2 hours).
The problem sometime the mini pc freeze when running tests (latency-test) so i have to restart.
I thought the bios settings was the culprit so i restore bios to default but the same.
Should i use i different distro or kernel?
 

[/attachment]  I know that there is a configuration 7c81_7i78x2d.bit, but there is the same on P2 as on P1 - 7i78. Another 4 axes. And I don't need that for the lathe. But I would like one MPG encoder for each axis - basically to be able to control the lathe "almost" manually. The rest of P2 controls the tool turret and on P7 there are limit switches and buttons.
So that's the goal.

tommylight wrote:

You would need this and maybe another DB25 to DB25 cable, also know as parallel port cable
eusurplus.com/index.php?route=product/pr...59_63&product_id=130
And might need a firmware flash, but do check what is already installed on the card using mesaflash

Basically what I meant, but better phrased.

Cheaper option from startech:
www.startech.com/en-ca/cables/plate25f16lp

I have an extra DB25 to DB25 (parallel port) cable (also startech actually, really old OG startech).

I didn't say it was a PATA cable, it's just a bit reminiscent of a PATA IDE cable.

I forgot about floppy drive cables!

Brings back good memories of ripping floppy drives out of old PCs.

langdons wrote:

You need a parallel port(female) to flat connector (think IDE PATA connector).

Dude, really ????
IDEA PATA is a 40 pin connector, and just to make you wonder, comes with a 40 wire and 80 wire flat cable.
Find out why.
And as a precaution, it is not a floppy drive connector either, that has ?? pins !

You would need this and maybe another DB25 to DB25 cable, also know as parallel port cable
eusurplus.com/index.php?route=product/pr...59_63&product_id=130
And might need a firmware flash, but do check what is already installed on the card using mesaflash

Yes it is possible to do that, at least from what it says on the MESA website.

You need a parallel port(female) to flat connector (think IDE PATA connector).

(Or, more like likely, an IDC 26 (male) --> DB-25(male) | DB-25 (female) --> DB-25 (female) | 7i78)

I think this is one such cable:
store.mesanet.com/index.php?route=produc...oduct&product_id=315

I think I have such an extra such cable, I suppose I could mail it to you or something.

How can i use a 7i96s together with a 7i78 to get 2 more STEPGENs?

My main board 7i96s was being used to control 5 axis Stepgens, but one has fried completely, and i was hoping i could expand the board with a 7i78 i have laying around, to control a total of 6 (4+2) stepgens. is this possible? What bit file should I use? Is there one available for it ?


Best regards
 

There is a 7I78X2 configuration: 7c81_7i78x2d.bit 

Do you need MPG encoders or high speed encoders+index?

Hmm...

I don't think VFDs really lose that much torque at low speeds.

Maybe at really low speeds they might, but you should be fine.

However, with a gearbox, halving speed doubles torque, which is not the case with a VFD at all.

I have opened an issue:
github.com/LinuxCNC/linuxcnc/issues/3668