Voron v2 Kinematic Bed Mount by Lightweight Labware - Stainless Edition

Kinematic couplings are a really neat engineering solution to two problems associated with precisely connecting thing A to thing B:

• how can I detach and re-attach thing A, and be sure it's in precisely the same place?
• how can I assure precise alignment even if things A and B are slightly changing size (for example, due to thermal expansion)?

They do this by exactly constraining the 6 degrees of freedom between the two objects, and not over constraining any beyond that. (For a really excellent hands-on demenstration of what this means, I strongly recommend nickw's fantastic tutorial on Pinshape.)

Exact constraint means that there is one and only one orientation in which things A and B can be connected. If you remove them and re-attach, they will retun to that exact orientation relative to one another. If thing A expands slightly with respect to thing B, there will still be one and only one orientation aligning them, even though the three connection points on thing A are now slightly farther apart.

If we are clever about how we organize the constraints, we can even make sure that the new orientation, post-expansion, keeps a target point on thing A exactly where it was pre-expansion. There are two common types of kinematic couplings, which differ primarily in wherethat stationary target point is located.

Continue reading here.