So my Maslow from EastBaySource has been lying around here for half a year, but now I’m finally taking the time to build it.

Also, I wanted my build to occupy the least space possible, so I made a table where I can tilt the Maslow at the right angle. Please refer to the picture below.

The core has all the bearings necessary to move the z-axis. The EMT is about 5 inches, actually just used the leftover after the cut for my mpcnc. Core is now just mounted using the screw holes provided, but i am working on a modified core design to more securily attach it to the sled.

the first iteration attempted to calculate the tilt of the sled (treating it as
a T with the chains at the top corners and the bit at the bottom), but it proved
to be a problem that was too hard for us to figure out (and we found it also
depended on the cutting forces involved)

the ring/linkage approaches solved this by simplifying the math to have the
chains always in a line with the bit.

take a look at the top mount linkage thread, that could be scaled pretty well
(although you have to watch how steep the angles get at the bottom corners and
if you clear them with your linkage).

Is this because of the weight distribution of the sled? (The weights near the bottom corners?)

No.

If you have a ring/linkage that lets the sled rotate freely and keep the chains
pointed directly at the bit to make the math simple (see my prior post), the
torque of the motor can cause the sled to rotate until it hits the limit of the
allowed movement. By adding weight to the bottom, you allow gravity to counter
the rotation.

(now that I think about it, I don’t know if anyone ever tried a ring for one
chain and a fixed mount for the other, with the weight on the sled being
symmetrical, in theory that could work)

I think there is a misunderstanding here, i actually have a ring that leds the sled rotate freely. But maybe the holes in the sides of the casing where the chain goes through need to be slightly bigger .

If you drive your sled to the 2 lower corners, your chains might rub on those openings. If they do, the chain will bend to reach the ring and center of motor, throwing off the math. I don’t think that there’s any angle possible to let you enclose the system and allowing for free movement. Even going with a pantograph (ala metal maslow) would be difficult to pull off (the lengths of the rods would have to be quite large).

the angles of the chains go from ~10 degrees from vertical (bottom near corner)
to ~10 degrees from horizontal (top far corner) so about 70 degrees of movement.
That requires a large slot to allow for the full range of movement.

now, if you are willing to sacrafice work area, you can reduce the needed
angles.

the 45 linkage would have similar problems as the arms attach to the sled and
swing through the same angle.

the top mount linkage has the advantage that all the movement can be done above
the top of the sled/housing (it just needs stiffer arms to make sure it doesn’t
flex too much)

So i have made some improvements since last time, mainly the encapsulation of the z axis and router. See picture below. Together with the vacuum hose this makes an almost dust free experience with noise levels below the painful level