Messages

1651

General Mach Discussion / Re: FEED RATE QUERY

« on: March 14, 2014, 07:46:27 AM »

So it will do 6" at .01/rev and 3" at .005/rev to arrive at the same spot.
So in my case of the axis both moving in the same direction it will be a combined feed of .015/rev???

Actual feedrate calculation is done internaly by Mach and do not know how it's being programmed internaly.
It's not that simple as the "guess" you posted.

Depends on what feedrate mode you are using, if starting from current velocity or no axis motion, your accel / velocity
/ steps per unit settings for the motor, motor rpm if G95 mode, etc.

The x & Z motors will need to accelerate and de-celerate and move at different feedrates to reach the same end
point which is based on 6.7" where  F.01 is inches per spindle rev for G95. Each axis motor is pulsed differently to move the controlled point to the final location over a period of time and distance and acceleration may be modified ( if possible) depending on time to achieve.  You would need to calculate each axis based on coded move and Mach's instruction for that move then apply to the individual axes for what you are doing.


Per above you have not provided all the info required to answer you question:

What will the actual feed rate be.[/quote)


RICH

1652

General Mach Discussion / Re: Problems with threading R3.042.040?

« on: March 13, 2014, 08:16:32 AM »

For threading the user should use a version 3.042.034 and above. Don't recall if there are problems with versions past .034
other than the latest version of Mach.

RICH

1653

General Mach Discussion / Re: Stepper Trouble

« on: March 13, 2014, 08:09:27 AM »

Small error in steps per unit and small backlash can add up over a lot of axis moves and thus seems like loosing some steps or small
inaccuracy.

Completely out of wack can be due to incorrect vel or accel settings for the motors and work your doing. Additionaly inadequate motor torque can cause lost steps when making very small axis moves like what one would find in 3d machining.

RICH


 

1654

FAQs / Re: Soft Limits Questions

« on: March 13, 2014, 08:00:06 AM »

Soft limits will restrict the travel and you get an error message if you command to go beyond them.
I don't have or use limit swithes but do use soft limits sometimes just in case. Can turn on or off easily.

RICH 

1655

General Mach Discussion / Re: FEED RATE QUERY

« on: March 13, 2014, 07:50:23 AM »

Graham,

G1 X6 Z3 is a a co-ordinated linear move. Yes, X will move 6" & Z will move 3" as you noted, BUT, that gcode is telling Mach to provide motion along the hypotenuse of those two moves ( along the programmed linear XZ path)  and that distance is 6.7" .

Mach or any contoller would not know that you doing something goofy / tricking the software to accomplish what only you know.If you coded for individual axis moves then the feedrate would be as coded.

Attached is info from the manuals for your reading,

RICH

1656

SmoothStepper USB / Re: Dead ... or alive.

« on: March 12, 2014, 06:46:02 AM »

Russ,
Don't have an answer for you but do have dumb question.

From a "fastener use" viewpoint....... Why does it matter if the pitch is maintained or is gradual?
The stress point is moved and intensification factor would still be subjective, and in calc's, the  max loading  would still be based on the thread geometry.
Even the max loading is subjective.

Just wondering if you are needing to address someones spec for the bolt........

RICH

1657

General Mach Discussion / Re: FEED RATE QUERY

« on: March 12, 2014, 06:14:07 AM »

You don't say if you are using it as a lathe or mill and also what feed rate mode is in effect.
I may also add that Mach would not know that the axes are moving in the same direction and would assume that X is perpendicular to the Z ( if a lathe ) and as such the distance would be 6.7".

RICH

1658

General Mach Discussion / Re: Mach3 with Zenbot - Scaling Issue

« on: March 11, 2014, 06:59:00 AM »

To use Mach3 with a 64bit OS an external motion controller, like a Smoothstepper, etc. must be used.
Are you are using one?

Also make sure that the your units are consistant for both Mach configuraton and Vetric and scale is set at 1.

RICH

1659

FAQs / Re: different pitches of axis

« on: March 11, 2014, 06:43:49 AM »

Yes you can have different ball screw sizes. In motor tuning, the steps per unit, accounts for different screws since they are calculated values.
You must however only configure Mach for Imperial or Metric. 

RICH

1660

General Mach Discussion / Re: Do I have a bug and is it a big one??

« on: March 11, 2014, 06:32:47 AM »

Suggest you create a new profile and delete the old one. 

RICH