Jump to content
Ultimaker Community of 3D Printing Experts
joshuaSmith2021

Estimated Time Algorithm

Recommended Posts

I have noticed that print times are often way off of actual print times. I use ~v3.0.0 with a Printrbot Simple Pro w/heated bed, if it matters. Almost all of my prints take about 30-40% longer than the estimated print time. I understand that estimating the print time is difficult because of lots of factors involved in printing.

 

What is the algorithm that calculates this print time?

Share this post


Link to post
Share on other sites

The algorithm works incredibly well for Ultimaker printers.   It is making assumptions about the accleration and jerk settings on your particular printer.  These are pretty high on (for example) the UM2 printer - 5000mm/sec/sec is the default acceleration.  "jerk" is 20mm/sec (not true jerk - this is a weird marlin terminology).

 

I think there *might* be a way to tell Cura what the acceleration is for your particular printer so that it calculates these print times more accurately.  I guess you have to know how long a typical retraction takes as well?  I suspect cura cheats and just has a certain amount of seconds for each retraction (versus knowing the E axis acceleration, max speed, retraction distance.

Share this post


Link to post
Share on other sites

It doesn't make assumptions; It uses the exact values the machine definition provides. In the case of Ultimaker, we set those to the correct values. The quality of contributed definitions can vary, so they quite often have (blatantly) wrong acceleration rates.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Question: How do you use your 3D printer?   172 members have voted

    1. 1. - For what purpose do you 3D print?


      • Professionally, I have access to a 3D printer at work
      • Professionally, I have a 3D printer at home that generates revenue, or assists me in my work
      • Hobby, I have a 3D printer just for fun

    Please sign in or register to vote in this poll. View topic
×

Important Information

Welcome to the Ultimaker Community of 3D printing experts. Visit the following links to read more about our Terms of Use or our Privacy Policy. Thank you!