So I’m constantly seeing references to dual endstops on these forums, but I’m not really understanding what this is (or if I have them on my standard issue LR2). It seems to have something to do with autosquaring(?) But im not sure. Is that what it is? Is it in FW or HW? Am I using it and not realizing it? Should I be?
A link to an explanation would be great!
Right now, before I run a cut, I spend about 10 minutes squaring my machine. If I’m missing a feature or technique that would make that faster or more accurate, please tell me because it’s my least favorite part of the operation.
First, no question is dumb, if you don’t understand…
OK, two end stops on the same end are used to re-zero the X axis that has the large carriage and two separate motors, one driving each end. When power is off, normally it is possible to move the carriage by hand, so one end could move getting it is likely for it to get ‘out of square’. Assuming the end stops are ‘square’, running the ends to the stops, simultaneously, should have both ends touching their respective stops at the same time. If they don’t, we keep driving the one that hasn’t touched till it does. Once both touching their own end stop at the same time, the gantry is ‘in square’.
Typically this is only done on the X or Y axis (the other axis and z only have one stepper so this technique isn’t relevant).
I hope this helps and the description is not to convoluted.
If you have separate drivers on an axis, you cam drive them indepentently. If you put an endstop at each motor, you can drive them to home and only stop each motor once it’s reached square. It ony works if you have each motor driven independently. You would know if you have it because you would have installed the endstops, and the firmware for the LR isn’t preconfigured.
The best way (IMO) to square the LR is to have a parking place where you always start. Have some kind of physical stop that you know is square (like the end of the table). Pull you machine to that end while you engage the motors and they will move in lock step from then on to stay square. On the LR and the Z, I also give each lead screw a twist and let it settle down again on it’s own, which releives any tension in the couplers before starting. It should take less than a minute.
I am in the process of understanding everything too for this CNC. While I print the parts, I am studying everything I can so I can have a decent understanding of how I wish to build it along with many updates and mods others have incorporated. There are a series of videos from a guy called Teaching Tech from Australia you might want to view. He describes, in detail, his build which includes dual endstops and autosquaring.
Search for teaching Tech and look for the following videos titles: