# Weight of chain causing inacuracy **URL:** \ **Category:** Technical Details\ **Created:** [May 14, 2020, 4:55am UTC](https://forums.maslowcnc.com/t/weight-of-chain-causing-inacuracy/13358 "2020-05-14T04:55:51Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Cannon9559](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/cannon9559/32/16661_2.png) [@Cannon9559](https://forums.maslowcnc.com/u/Cannon9559)\ **Post date:** [May 14, 2020, 4:55am UTC](https://forums.maslowcnc.com/t/weight-of-chain-causing-inacuracy/13358/1 "2020-05-14T04:55:51Z")
I’m just curios if the weight of the chain between the sled and motors is accounted for. I’m sure that it would only cause a minor issue with the accuracy of the machine, but something to consider. The more chain that is let out, the heavier it becomes. This must be why the Maslow is less accurate in the bottom corners? This could all be taken care of in software. ---
**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:** [May 14, 2020, 5:27am UTC](https://forums.maslowcnc.com/t/weight-of-chain-causing-inacuracy/13358/2 "2020-05-14T05:27:56Z")
look for a topic ‘sources of error’, there are a lot of possible errors. What you re noticing is what we call ‘chain sag’ and the holey triangulation does make an estimate of it, along with ‘chain stretch’ here there is just a smidge of space between the pin and the link in the chain (if you think about it, 1/1000" gap here multiplied by 500 links adds up to a lot of error) good thinking, we want people thinking like you, so I want to bring you up to speed 🙂 but the bigger cause for the error in the bottom corners is that the chains get so close to vertical that there is not much force available from gravity to pull into the corners. This combines with the chain sag problem in that you have the longest amount of chain anywhere in the workspace under the least amount of tension anywhere in the workspace, so the most sag of anywhere in the workspace the stock calibration doesn’t account for this. David Lang ---
**Author:** ![kayaker37](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/kayaker37/32/12681_2.png) [@kayaker37](https://forums.maslowcnc.com/u/kayaker37)\ **Post date:** [May 14, 2020, 1:13pm UTC](https://forums.maslowcnc.com/t/weight-of-chain-causing-inacuracy/13358/3 "2020-05-14T13:13:23Z")
I was looking through these last night, not that I understand much of what they are doing, but just blown away by how much thought and effort that people have put into this. > [@List of sources of error](https://forums.maslowcnc.com/t/list-of-sources-of-error/7523): > > I was explaining the issues we are fighting with for accuracy to someone and started enumerating all the potential sources of error. I thought it would be good to go through them all and list how they are (or are not) being addressed as of the beginning of Nov 2018. This assumes that the chains, sprockets, chain slack are all kept in the same plane so that there is no error from the chain attempting to skip or the efforts to prevent it from skipping. This is assuming triangular kinematics (usi… > [@The Zipper Tree Challenge... because](https://forums.maslowcnc.com/t/the-zipper-tree-challenge-because/8455): > > Now let me say I definitely enjoy the creativity and dedication of Maslownians slight_smile In the last 2 years, there were a lot of talks about calibration, searching the set of necessary parameter, finding how to set those parameters in a simple way, yet dealing with everyone having made their own slightly or vastly customised frame. There were posts about getting oval shaped circles, parts slightly distorted depending on where on the work space they were cut, observing wavy “straight” lin… ---
**Author:** ![aluminumwelder](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/aluminumwelder/32/9362_2.png) [@aluminumwelder](https://forums.maslowcnc.com/u/aluminumwelder)\ **Post date:** [May 15, 2020, 7:45pm UTC](https://forums.maslowcnc.com/t/weight-of-chain-causing-inacuracy/13358/4 "2020-05-15T19:45:32Z")
If you use treat the maslow as a 4x4’ machine a lot of these problems simply vanish and corners are much more accurate.