Newbie here, just got an Openbuilds 1010, black box controller. I drew a grid pattern in Easel with 2" centers using the replicator app for a waste board…when I ran the job, the actual pattern came out 2-1/2" x 2-1/2", unsure why. Then I down loaded the drawing for some material hold downs that were drawn in Easel, they should have been 5" in length as show on the layout, they cut to 6-1/4" long. Is this an Easel thing, is it the cnc or is it me?
Most likely incorrect step/mm values for your X/Y/Z axis.
(GRBL parameter $100 for X, $101 for Y and $102 for Z)
Take out a ruler, a fine bit or V-bit and measure how far each axis move by commanding a jog.
Command say a 100mm jog, what is the actual travel?
Measuring over the longest distance possible give you the most precise numbers for re-calibration calculation.
To find your current GRBL values (The rules the controller follow) open Easel, press CTRL+SHIFT+D to open Machine Inspector window (MI). In the Console type $$ and press Enter.
A list of GRBL parameters will be listed below, running from $1…$134
If you report back your commanded vs actual movement values and your $100-$102 parameters we can assist you with the math. Its not complicated, but can be overwhelming for newbies. We have been there 
Welcome to the forums
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This thread addresses it pretty clearly.
Calibrating my X-carve 1000 - X-Carve - Inventables Community Forum
This worked out great!..thank you for the info
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