Z axis rigidity

[TonyStark39 (Jesse)]

Not sure if this is even a problem as I haven’t ordered my unit (X50) yet. Had a thought of either OneFinity making the spindle mount wider/taller so as to increase the surface area on the spindle/router orrr to double up on the mounts. I personally don’t need nearly as much travel on my “Z” as they allow with only having 1 mount. I only require/need about 3 to 4 inches of travel. Would be nice to see a spindle mount that is at least 4 inches or more tall. The increased surface area/holding/clamping ability would be so nice to have. I’m about to order and I’ll probably get an extra 80mm clamp so I can have one on top and bottom of my spindle. Food for thought…

[Aiph5u (Aiph5u (not affiliated with Onefinity))]

Hey Jesse,

welcome to the forum.

@TonyStark39

Had a thought of either OneFinity making the spindle mount wider/taller so as to increase the surface area on the spindle/router orrr to double up on the mounts. I personally don’t need nearly as much travel on my “Z” as they allow with only having 1 mount. I only require/need about 3 to 4 inches of travel. Would be nice to see a spindle mount that is at least 4 inches or more tall. The increased surface area/holding/clamping ability would be so nice to have. I’m about to order and I’ll probably get an extra 80mm clamp so I can have one on top and bottom of my spindle. Food for thought…

Tom and I discussed this here the other day in:

• Any hobbyist grade solutions for adding automatic tool changes to onefinity?

@Aiph5u

What I imagined among other things is: What if there were two 80 mm mounts, one on top of the other (thereby four linear bearings instead of two for the Z slider), but the Z rails would need to be much longer in order to retain Z travel length, but for the rest, leaving the Z Slider design as it is?

@TMToronto

I also consider buying and using a second 80mm mount. Right now the linear bearings being used are 70mm long, and the 80mm mount is 51mm high. If four new linear bearings are purchased that are 50mm long, then the overall double mount would be 102mm. The minimum amount of Z travel we would then loose would be 102mm - 70mm or ~ 30mm.

@Aiph5u

I did not think of shorter bearings, that’s a good idea. 30 mm loss of Z travel is really not much, but we would only loose so little if the two 80 mm mounts would touch each other. I imagined the two bearings were further apart so that the leverage is really well distributed. See other Z Sliders. The further apart they were, the more weight you could put on them. Also if I would want to use the retrofit ATC Adapter for my existing spindle instead of a new ATC spindle (I’m not decided yet), I would say that such an ATC Adapter requires a second attachment, but a bit higher. In both cases, you would really need longer Z rails, otherwise you lose a lot of Z travel length.

But in any case, the shorter bearing would be something I’d like to try out

Further reading:

• Universal Z Axis Assembly
• Has anyone replaced their Z axis assembly for greater travel?

[TMToronto]

I just picked up my second 80mm mount to use with my new ATC spindle. In preparation I also purchased two of the regular length LM16 linear bearings. My calculations (I can provide them if you wish) leave me with 88mm of travel using the two mounts. I would need to subtract from this the buffer I wish to leave for the z assembly to stop at the end of each travel as I am using homing sensors.

Given the 1F team’s innovation and responsiveness to their ever evolving and growing user base, it would not surprise me if a more robust ‘spindle focused’ z assembly with greater travel will be in their future plans. The newest X50 offerings, with claims of added rigidity, would definitely support such a new upgrade. I remain hopeful, but in the meantime will continue with my own version of z assembly upgrade.

[Aiph5u (Aiph5u (not affiliated with Onefinity))]

Hey Jesse,

@TonyStark39

The increased surface area/holding/clamping ability would be so nice to have.

which spindle do you intend to use?

My spindle manufacturer writes in the manual that the 80 mm spindle requires the clamping force be spread over 8000 mm² of surface. With 80 mm diameter = 40 mm radius this would give

$ bc -l
pi=4*a(1)
8000/(2*pi*40)
31.83098861837906715400

31.8 mm minimal height of spindle mount. Since Onefinity 80 mm mount is 2″ (51 mm) high this is enough (for this spindle).

Of course, the leverage force exerted on the Z rails and their linear bushings will be greatly reduced if distributed over a greater length, such as by stacking the two mounts on top of each other

[TonyStark39 (Jesse)]

Hey Aiph5u,

I’m going with an 80mm spindle. I may be overthinking this as I haven’t received my machine in yet. I’m looking forward to it though!

[clayf (Clay)]

Hey Yall,

Did anyone find any good solutions here? I use my x50 for aluminum and would like a little more strength.

Any z axis recommendations or did the double mount work for anyone?