Origin and Safe Z

[Anonymous]

Hello,

I'm a new user of Fusion 360 but I have some experience with other CAD/CAM software. 

At my first project I'm having some issues:

- Let's say that I have many pieces for milling from a large piece board(see "Board" in att.). My origin is placed on my left side of the board(please see "Origin" in att.) and every time I want to mill a piece my CNC machine is starting from the origin but at the end pf the program is not coming back to origin again. Also I couldn't find the Safe Z option. After the start of the program I would like to raise the Z axis to a Safe Z value( +10 i.e) and then to move from origin to the piece from the board. Right now, after I start the program, the CNC machine is moving to the piece with Z=0 is not OK.

Thank you in advance.

[LibertyMachine]

Welcome to the forums! What are you using for a machine and what post processor are you using? Does your machine have home position switches?

[Anonymous]

I'm using Mach3 software on my CNC machine.

[Steinwerks]

I'm guessing that @LibertyMachine is correct EG home switches.

Third line is something like this:

G28 G91 Z0.

correct?

[Anonymous]

Yes. You are right.

How can I solve this?

[Steinwerks]

Well the easiest way is to eliminate the homing code.

Before going that route though, is there a process by which you can set a home position? What is your machine?

A coworker has a Sherline mill with no homing switches but we just jogged it to the upper right corner of the machine and homed it, and I told him to just do that every time he turns the machine off and re-home every time it turns on to keep his work offsets if he wants to. After that you have to use Work Coordinate Offsets in the control. I have no experience with Mach3 so hopefully some others will chime in who are more knowledgeable.

@daniel_lyall has some very extensive insight IMO.

[daniel_lyall]

yep in the setting you turn homing off then do what @Steinwerks said.

I have a big router quite often, it takes longer to home the machine than doing a cut so I just turn it off and just home above the part.

in setting have it like this
 

then you just hit this button and it will home in places, where the machine is at the time the button is hit, just make sure the Z axis is almost at the top of it's travel.

[Anonymous]

Thank you all for replies. I will try your proposal in regards of Origin.

But I still don't get it. Is there a way in Fusion 360, after choosing the Origin(x=0, y=0, z=0), when I start the program to raise the Z axis to a safe position and then travel to the first position where the CNC will do something(starting to cut, to drill...)? See "Add code.png"

[daniel_lyall]

This is all in the mach3 manual. http://www.machsupport.com/help-learning/product-manuals/

You home the machine first (Machine Zero) be it with switches or by moving it to a safe position, this is a must do FIRST.

Then you zero the machine to the part (Work Zero) X and Y then you set the Z height be it top of part, table whatever. useing a tool setter, height setter, tool probe or probe.

or do it by eye.

If you do it by eye lift the Z axis back up after you have set the Z height.

The setting for safe Z is in config / Safe Z setup, this is only for if you hit the stop button.

The height for the machine to goto when you hit cycle start is set by you in the cam.

If you have left the tool sitting on top of the part when you hit cycle start. smack your hand, lesson learnt now don't forget to not do it again.

If you stick to the above you will be fine I have written this out about a 100 times. I did not know this the first time I used Mach ever then I got told RTFM, I did that and well I was fine after that.

If you wont to know more about Mach3 Tool height setting and that sort of stuff, Please post on the mach forum there are guys there that have use mach3 from day 0.

you can ask here If you wont there is not that many people who use Mach3 come on here, so a response might be a waiting game Mach forum will be faster.

http://www.machsupport.com/forum/index.php

If you wont some one on one that be $$$.

[daniel_lyall]

Now to you setting a Z height in cam.

in the pick below you will see that feed height is set to 5 mm, that means when you hit cycle start the machine will move to its start position with the Z going down to 5mm.

This is what you need to make sure you have set the other heights above feed height have to be the same or greater. 

 

this is a shot of the code the above file put out.

(DUST SHOE TOP)
(DUST SHOE)
(T2 D=6.35 CR=0. - ZMIN=-18. - FLAT END MILL)
N10 G90 G94 G91.1 G40 G49 G17
N15 G21
N20 G28 G91 Z0.  this is rapid to Z axis Machine Home/zero
N25 G90

(2D CONTOUR1)
N30 M5
N35 M9
N40 T2 M6
N45 S21000 M3
N50 G54
N55 M9
N65 G0 X22.874 Y42.808   this is move to cutting start position in X and Y
N70 G43 Z7. H0                  this is move down to Z 7 from machine Home, the N20 line
N75 G1 Z3.22 F700.            this is move down to Z3.22 and a feed of 700mm/min

Then after the above it starts to cut.

I have attached my Mach3 post it has some improvements in it from the standard Mach3 post, you can turn some stuff on and off.

But for a start don't do it to you know what will happen (safety Nazi).

From the snap shot you posted it is clear you are not setting Machine home you need to learn the differences and importances between Machine Zero and Work Zero.

If you have a read of the Mach3 manual it is in there please have a read of it. (other wise the saftey nazi will come and take your machine of you):smileywink:

[Anonymous]

 Hello again,

The part with 0,0 origin is solved now - thank you all. But, there is still one issue.

After I cycle start the CNC is moving from the 0,0 to to first location where he will do something with the Z axis still on 0. This is NOK for me. I would like, after hitting the start button, to raise the Z axis with a 5 mm safety and after that to move to the first location. Thi situation is also present after the last thing was done by CNC and then he will travel back to 0,0 origin.

Below is an example where I want to make 2 drills.

(T2 D=6. CR=0. - ZMIN=-19. - FLAT END MILL)
G90 G94 G91.1 G40 G49 G17
G21
G28 G91 Z0. ???????? I will need to raise 5mm and then to move to the first drill location
G90

(DRILL1)
M5
M9
T2 M6
S7760 M3
G54
M9
G0 X70.282 Y42.032
G43 Z3. H2
Z2.
G98 G81 X70.282 Y42.032 Z-19. R1. F300.
X245.574 Y56.061
G80
Z3.

M9
G28 G91 Z0. ??????????? After the last drill I would like to raise the Z with 5 mm and then to travel to the 0,0 origin
G28 X0. Y0.
M30

What it will be the solution? I am able to solve this with Fusion 360(to set something in the CAM) or I will have to add manually some code in the post process program?

Thank you.

[daniel_lyall · Accepted solution]

That should make it go upto the top of the Z travel or Z home, G28 is return home

[mbelusa.mail]

Hi,

I had same issue, i hope help you with my edited post processor ....

enjoy 🙂