# Accuracy issues: off by 1/16" on both X and Y axes

**URL:** <https://forums.maslowcnc.com/t/accuracy-issues-off-by-1-16-on-both-x-and-y-axes/12246>\
**Category:** Uncategorized\
**Created:** [January 27, 2020, 5:32am UTC](https://forums.maslowcnc.com/t/accuracy-issues-off-by-1-16-on-both-x-and-y-axes/12246 "2020-01-27T05:32:04Z")\
**Posts on this page:** 1\
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**Author:** ![dlang](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/dlang/32/859_2.png) [@dlang](https://forums.maslowcnc.com/u/dlang)\
**Post date:** [January 27, 2020, 12:34pm UTC](https://forums.maslowcnc.com/t/accuracy-issues-off-by-1-16-on-both-x-and-y-axes/12246/2 "2020-01-27T12:34:51Z")

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This just means that there is some error in your calibration or your machine is  
flexing during cuts.

first make sure that the motor mounts, top beam, and brackets holding the top  
beam are not flexing during cuts (recording video from a tripod zoomed in on  
the motors will show even small movements easily)

in terms of your calibration, accurate measurements are a must. see the  
side-discussion about class 1, class 2 and unrated tape measures in the topic at

> [@In search of accurate measurements](https://forums.maslowcnc.com/t/in-search-of-accurate-measurements/9581):
>
> at one point, someone posted a picture of a caliper setup that they had which used a tape measure that let you measure down to 1/10 mm over whatever length tape measure you have. I have created an item in onshape with the idea of 3D printing two of them, one to go on the end of a tape measure (any tape measure up to ~1" wide), and the other to be used for the measurement. These have pins to work with the holey triangulation calibration holes. However, my experien…

also you may be interested in lookup up the topic “sources of error” (sorry, my  
browser is misbehaving, so I can’t pull up the link at the moment)

you don’t say if you are using standard triangular calibration or the new holey  
calibration that’s available in webcontrol

for the distance between the motors, did you measure it with a tape measure? or  
did you use the chain measurement? if you have an accurate tape measure, it’s  
best to measure this as the chain isn’t exactly 6.35mm per link.

David Lang

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