THE GRIZZ

[atomarc]

Peter. We had planned on utilizing the VESA mount as well..... but the plans have changed and the new monitor has no vesa... probably end up using "duck-tape" to hold it on!!

[atomarc]

The mail man delivered a roll of "tape"..... let the taping commence! The bellows are complete and the next chore will be home switches and what ever goes along with that.... If anyone has any home switch "hot tips"... now is the time



(figured it was about video time..... subscribe / like so i know you are there )






(pictures because pictures are good.... ummmk)











(Y all the way forward)





(Z upppppp!!!)





(puttin' the squeeze on the bellows to promote VHB adhesion.... )







(this....)





(around here.....)




(Bella said she approves this message!)

[phomann]

Hi,

It's best to mount the switches so that they don't get destroyed if the axis doesn't stop. One solution is to also mount a hard stop near the switch so this can't occur.

Also when you wire them wire all the limit switches using Normally Closed(N/C) switch contacts. That way, the limit will be tripped if a plug comes out or a wire breaks.

Also, Wire all the switches in series using only a single input. When a limit switch is hit, the software doesn't care which limit is hit, just that the limit is tripped.

You can also use this string of limits as the home switches as well. When homing, one axis is homed at a time, so the software knows which home switch is tripped .

When wiring the switches in series, don't use a single piece of wire, daisy chaining between each switch and then running back to the controller connector as this effectively makes a loop antenna, ready to pick to any stray EMI. It it preferable to use a shielded twin core cable such as below.
https://www.homanndesigns.com/index....roducts_id=325

Run it from the connector, cut into it at the switch position, find one of the cores and splice the switch into it. Do this for each of the switches. At the last switch, connect the return core to the last switch, similar to the limit/switch wiring in the link below.
http://www.homanndesigns.com/pdfs/EN010_V8.pdf

Cheers,

Peter

[jiggerinc]

Haven't looked too deep into this for CNC mills, but I prefer inductive proximity sensors for accurate and repeatable positioning on 3d printer's Z axes. If the hardware supports it, I'd prefer physical limit switches, 2 per axis, tied to hardware interrupts to prevent crashes; and then a single inductive proximity sensor per axis to set the home position.

[pippin88]

Very nice work on the way covers and mounts

[atomarc]

Well...this is all very new to me so I'm still learning the basics of limit switches. There is a lot of info on this site about it and I'll do some reading.

Right now we (Nick and Stuart) are planning on having home limits at the extents of the 3 axis. These will be micro switches and when a home command is given, all 3 axis will respond simultaneously in the proper direction until a switch is hit. The limits in the other direction will be soft limits we set in the software. This is how I understand it...that may change as I read and get feedback from folks that actually have done this...we'll be using Mach-4, a smooth steppper and the stepper driver board.

And thank you for the encouraging comments about all facets of this build so far, still have a ways to go!

Stuart

[DJEkim33]

Well...this is all very new to me so I'm still learning the basics of limit switches. There is a lot of info on this site about it and I'll do some reading.

Right now we (Nick and Stuart) are planning on having home limits at the extents of the 3 axis. These will be micro switches and when a home command is given, all 3 axis will respond simultaneously in the proper direction until a switch is hit. The limits in the other direction will be soft limits we set in the software. This is how I understand it...that may change as I read and get feedback from folks that actually have done this...we'll be using Mach-4, a smooth steppper and the stepper driver board.

And thank you for the encouraging comments about all facets of this build so far, still have a ways to go!

Stuart

This is the easiest way to get it done. And if you have the input capability use a separate input for each axis. If you get a short or fault in one you will know where to start looking. I have barely scratched the surface of using up my breakout boards I/O interface. If you can separate the Z axis homing from the X and Y it is a bit safer. My X travels fast and if it starts to home at the same time as Z there is a chance I can hit the tool into the vise if I was being careless. I know we all say that we will be super careful about stuff like this but it happens. I have a can of tools that got destroyed from simple learning mistakes like this.

[atomarc]

DJEkim33,

A great heads up..didn't think of that type of crash, thank you.

Stuart

[SCzEngrgGroup]

This is the easiest way to get it done. And if you have the input capability use a separate input for each axis. If you get a short or fault in one you will know where to start looking. I have barely scratched the surface of using up my breakout boards I/O interface. If you can separate the Z axis homing from the X and Y it is a bit safer. My X travels fast and if it starts to home at the same time as Z there is a chance I can hit the tool into the vise if I was being careless. I know we all say that we will be super careful about stuff like this but it happens. I have a can of tools that got destroyed from simple learning mistakes like this.

You should ALWAYS home Z first, for exactly that reason!

Regards,
Ray L.

[atomarc]

You should ALWAYS home Z first, for exactly that reason!

Regards,
Ray L.

We have not purchased Mach-4 yet but I wonder if there is a feature that allows a home command, then waits until 'Z' homes before activating X & Y to run to their homes...seems like that would be a neat thing to have in the program. Again...I'm brand new to this so this is great info and I'm hoping the software is highly configurable for issues just like this.

Stuart

[SCzEngrgGroup]

We have not purchased Mach-4 yet but I wonder if there is a feature that allows a home command, then waits until 'Z' homes before activating X & Y to run to their homes...seems like that would be a neat thing to have in the program. Again...I'm brand new to this so this is great info and I'm hoping the software is highly configurable for issues just like this.

Stuart

The homing sequence in Mach3 and Mach4 is controlled by scripts the user can easily modify. The default scripts home Z, then X/Y.

Regards,
Ray L.

[atomarc]

The homing sequence in Mach3 and Mach4 is controlled by scripts the user can easily modify. The default scripts home Z, then X/Y.

Regards,
Ray L.

Those darn developers are just too clever....they think of everything, don't they!

Stuart

[atomarc]

In an effort to accomplish just one thing today..... all 3 stepper motors are now wired and assembled... the two end caps for the nema 23's where printed in black PETG..... the cover for the Z stepper is a commercial piece, i think it said made in Israel on the inside..... and some pictures from along the way. - Nick

(photo dump.)

[Fastest1]

I like all my home and limit switches on a single pin for each axis. If you have the extra pins.
Though z moves first the other 2 move simultaneously. Dont forget a pin for a probe and or tool setter.


Sent from my iPhone using Tapatalk Pro

[atomarc]

I like all my home and limit switches on a single pin for each axis. If you have the extra pins.
Though z moves first the other 2 move simultaneously. Dont forget a pin for a probe and or tool setter.


Sent from my iPhone using Tapatalk Pro

That makes sense to me. I downloaded a demo of Mach-4, and doing only a cursory look I didn't see where you configured a single axis to home first, then when homed, followed by the others. It must be in there somewhere..I'll scout around some more

Stuart.

[mikegiraud]

Cleaning up my stepper wiring has been on my to do list for 2 years. It stalled when I couldn't find the stl files for the end caps for the bigger 60mm Nema 23 steppers. Can you share where you got your files for the X and Y axis stepper caps? I've only found the small 56mm caps on GrabCad.

Also, where did you buy the nice injection molded cap for the Nema 34 Z axis?

[atomarc]

Cleaning up my stepper wiring has been on my to do list for 2 years. It stalled when I couldn't find the stl files for the end caps for the bigger 60mm Nema 23 steppers. Can you share where you got your files for the X and Y axis stepper caps? I've only found the small 56mm caps on GrabCad.

Also, where did you buy the nice injection molded cap for the Nema 34 Z axis?

Two years is a long time!!! I have files for the left / right nema 23 570oz motors and will post them.


The injection molded cover came from D.Y Engineering... looks like they also now have nema 23 60mm covers as well! D.Y. Engineering - Welcome!



NEMA 23 COVER LEFT - https://drive.google.com/file/d/0BzT...ew?usp=sharing

NEMA 23 COVER RIGHT - https://drive.google.com/file/d/0BzT...ew?usp=sharing




- Nick

[atomarc]

Thought i would put it out there.... if anyone is in need of new "OEM" take off G0704 parts pm me. All the parts have zero time on them (plugged in to make sure everything worked)... disassembled right out of the crate..... You have a burnt'-up motor? I have just the thing(s) for you!!!


(all the lead screws and associated parts, complete motor controller,motor etc............)

[atomarc]

finished up the table end plate "mods" by completing the drip edge... a piece of 14g to shed coolant away from the dovetails on the table / screw.....

[atomarc]

Updates from the motherland...

- Home switches.... made up some simple covers for the X & Y switches and printed them in black PETG plastic....a snug "Friction" fit holds them on the aluminum bases...

- The hole in the column.... where the Z hand crank use to reside.... made a cool 3D printed plug.... to fill the hole....

- Mounted the Z home switch and made a switch contact that is adjustable

- Buzzed up a neat Y axis home switch actuator out of some flat bar...... drilled & tapped the saddle

- Began work on the X home switch mounting..... had to do some slight back tracking on the front oil manifold..... junked the "machined" one and replaced it with a 2 push to connect 90's..... due to some previously
unseen clearance issues where everything joins together on the front saddle... (oil line, home switch, front way covers (tin), front table tin (think tormach)).... after some head scratching we figured it out...

- Link to google drive if anyone wants the STL file for the "column hole plug-cover". https://drive.google.com/file/d/0BzT...ew?usp=sharing



(switch on plate)






("like a glove" - Ace Ventura: Pet Detective )











(the switch has landed...)





(cover on... check!)





(the z switch actuator.... adjustable / locks with set screw)





(thought this was a cool picture... I like the sparks... and the "blurring". (grinding end of set screw for Z switch) )





(oh yeah.... that plug cap cover thing..)







(aww yes... the little steel thing from hell! )







(when it sounds like a good idea at first....... and then you actually start doing it....)







(drilling & tapping saddle for home switch actuator)









(and shes all screwed on)







( version 1... December 20, 2016.....)





( version 2... June 1, 2017..... has it been that long?)





till....... tomorrow!!!




- Nick