Help with STL file and exact dimension on printed object.

So I made a bracket in autodesk inventor and exported it in STL. Its converted to G-Code with Slic3r as standard. When I printed the part, its bigger by a certain percentage, Like instead of 8mm as specified in Inventor, its 8.40mm on the printed part. Im using a Mendel. I included a picture with the dimension on the part and the options box for saving the file for STL. They are what I used to saved the file to STL. What are the settings I should you use to export the stl file to print the object with the correct dimension for the object I drew?

The problem may not be with the STL file, but with your printer calibration. Have you printed calibration objects on your Mendel (like the usual 20x20x10mm cube), and checked that their dimensions were accurate?

Providing the STL would allow us to check its dimensions.

My printer is not calibrated in the X and Y. Only the Z-axis is calibrated. Using a 20 x 20 x 20mm test cube. Just printed the cube, Z is 19.97mm +/- 0.2mm, but X and Y are both 23.26mm +/- 0.2mm. What is the method to fix this? I did read the calibration page for the X and Y, but the formula seems confusing although the concept is simple. May need a better explanation.

Edited 1 time(s). Last edit at 11/24/2013 09:33PM by chuttney1.

You probably need to flash your firmware to calibrate your printer.

There are a few things you need to provide.

• what firmware? (sprinter, marlin)
• what belt pitch you're using (GT2, T2.5, T5...)
• motor step angle
• pulley tooth count

From this data a tool to easily get the right values for "steps per millimeter" is Josef Prusa's calculator: [calculator.josefprusa.cz]

Am I to understand that you just got this printer? Any supplementary info may be useful. Is that a Prusa Mendel, or the original Mendel?

Its more like a build taking over 6-7 weeks, mainly done on Saturdays as part of the Maker Club at Cal State Univ. Long Beach. Finished the build two weeks ago. Print is the Prusa Mendel, iteration 2. With the information provided, I'll be on to it right away. Thank You.