Measuring Wrong

HI guys
I was getting Board edge detection Error 400.
After reading some posts, I found that the sensor
on the bottom of the truck(2 Diodes) was covered
in dust from the inside. How on a sealed unit?
Anyway I removed it peeled away the glue on the seam
popped it open cleaned it and put it back together.
The machine seems to work except its telling me
my board is 28.5" long but its really 35.5" long.
Any thoughts on why its measuring wrong?

Thx Jeff

Your machine needs calibrated soo do a search "calibrate" with these quotation marks or look in manual,,thats my guess
denny

Hmmm, 7" difference in the board's measurement...

your machine is fine....your project is 35.5 inches long and then you selected stay under rollers which requires 3.5 inches extra on both ends therefore creating your 7 inch difference.