[Kosh]

Just wanted to post my solution to have a z-axis prox sensor mounted for homing the Z-Axis (I found that if I didn't retract it high enough during homing, it could hit the gantry brackets, and didn't want to do it manually).

So I went into Fusion360 and designed myself a nice little bracket that mounts on the back side of the Z-Axis carriage, using existing 6 mm holes. It spans three of the holes and rises high enough to cantilever a proximity switch over the top of the Z-axis top plate. I had it 3D printed at Shapeways.com in "Black, Strong and Flexible", basically laser sintered nylon.

Came out perfect and works like a charm! Here the pictures:

[ZamcoLaser]

Awesome job! That looks fantastic. Would you mind posting your drawing file for us? I'd love to have one of these so that I can have soft limits on my Z to keep it from raising to high. That is excellent work sir.

Zak

[ablythe]

Nice design and execution... I'm still new to the CNC scene (just recently finished building a PRO4848). Can you explain the advantage of having the z axis proximity sensor? I thought the Z axis is normally zeroed at the work height... typically by a touch plate. I'm trying to get my head wrapped around what this sensor does. Is it to prevent the Z axis from raising too high?

Thanks,
Andrew

[LeeWay]

Right. It's an upper limit switch. Very nice add on.
Are you going to change the homing routine to move Z first? On mine when I home it now, Z is automatically set at home regardless of position. Just have to be aware of the Z position before I home it.

My mill homes Z first, the Y, then X.

[Kosh]

Right. It's an upper limit switch. Very nice add on.
Are you going to change the homing routine to move Z first? On mine when I home it now, Z is automatically set at home regardless of position. Just have to be aware of the Z position before I home it.

My mill homes Z first, the Y, then X.

yes, that's exactly what I did. Like I said, I found out the hard way right after finishing my build that if you leave the Z axis down and try to home, it will hit the gantry plate when homing Y!

That's when I conceived this bracket.

[Kosh]

Awesome job! That looks fantastic. Would you mind posting your drawing file for us? I'd love to have one of these so that I can have soft limits on my Z to keep it from raising to high. That is excellent work sir.

Zak

I can do better Zak, I can make it available for you to purchase on Shapeways.com. It's about $48, I won't put a markup on it.

But... do you want to use the same prox sensor? I can give you a link, but i think I need to mod it first, it was ALMOST too tall, and should be shortened by about 1/2 inch (12 mm).

Let me know, or if you want a different length sensor and I can adjust it.

Also, assuming you have the 8" Z and not the 12" one?