it only lags when your currently crafting something if it not crafting there is no lag

yes it seem a problem in the code when reaching a certain lenght of belts
probably a number codded on 8bits or such
sadly their is no warning or hard limit
and until the computer will get 100times my power it can be obsolete
such issue hapend in the new game but it lag all the time from menu to ...crash to desktop
probably one of the first game i ever refund since i just canot play it even laggy
its sad because i get a lot of fun with this one and im not sure than upgarding my config to a medium rig will be enought

remove all conveyors and replace with new. solves it for me.