Prusa i3 remake -> results are scaled up

Hey thank u for all informations i get here. But now i have prob and i cant find any way to fix it.

So i build s prusa i3 remake... i fix some things an the prusa print fine. So but now the Printer scale all things up...
Course i dont know why... i sliced with sli3r and i dont see any mistake, but all parts i print are a litte bigger than the normal... about 10/15% up than the original parts/things... so my question is, is it software mistake or a hardware mistake? Ithink the software/firmware has a mistake, but where is it?
I hope anyone can help me

Edited 2 time(s). Last edit at 12/26/2014 04:51AM by Backjump.

Perhaps you have to calibrate your steps?

look here:
[www.instructables.com]

and here:
[reprap.org]







My i3 printing a skull:
[youtu.be]

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Prusa i3, Ramps 1.4. Catnozzle 0.4mm
SketchUp - Enveloping Globoid Worm Gear - Part One - 3D Printed: [youtu.be]
DesignSpark Mechanical & more precise screw thread: [youtu.be]
Nicer Screw Thread In SketchUp ( Bolts,Nuts): [youtu.be]
How To Model A Heart Shape In SketchUp: [youtu.be]
How To Draw 3D Printable Snap Fit Ball Joint In SketchUp: [youtu.be]

Ah ok... but my prints are good...the only things are the bed center is not in the middle... and thr printer scale up the results. I think its an software setting or not?

You will probably have to lower your steps per unit as plasteroid said.

For example:
Now you have 80 steps per unit and it should be 40 steps per unit.
If the centre is at 5 units, the printer should go 200 steps (40 * 5)
but the printer is going 400 steps (80 * 5).

That's why the print isn't in the middle and everything is a little bigger than it should be.

Ah okay i understand, but where must i change this parameter?

i only find this on the configuration.h on my marlin firmware

// default settings //#define _AXIS_STEP_PER_UNIT {93.74, 94.184, 2564.1,700} from sprinter for printrboard
// X, Y, Z, E steps per unit - Metric Prusa Mendel with Wade extruder: (current setting / actual reading * 100)

#define DEFAULT_AXIS_STEPS_PER_UNIT {100, 100, 4000, 700} // default steps per unit for ultimaker

Edited 1 time(s). Last edit at 12/26/2014 04:49PM by Backjump.

Quote
Backjump
Ah okay i understand, but where must i change this parameter?

i only find this on the configuration.h on my marlin firmware

// default settings //#define _AXIS_STEP_PER_UNIT {93.74, 94.184, 2564.1,700} from sprinter for printrboard
// X, Y, Z, E steps per unit - Metric Prusa Mendel with Wade extruder: (current setting / actual reading * 100)

#define DEFAULT_AXIS_STEPS_PER_UNIT {100, 100, 4000, 700} // default steps per unit for ultimaker

Use this calculator to get the correct values:
[prusaprinters.org]

Steve

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My updated Instructable on our Prusa i3 Build
[www.instructables.com]

Ah perfect i do this calculation later. Must i change it on the fimware direct example in the configuration.h?

Quote
Backjump
Ah perfect i do this calculation later. Must i change it on the fimware direct example in the configuration.h?

Yes, the values for X, Y, Z and extruder steps:
#define DEFAULT_AXIS_STEPS_PER_UNIT {100, 100, 4000, 700}
These are the values you change

Steve

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My updated Instructable on our Prusa i3 Build
[www.instructables.com]

Hey steve, i fix the parameter on the config.h and i measure and calculate the new steps. I put x to 80 and y 80 and z 4000..

And it works fine... thank u so much steve!!