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I bumped the mirrors a few times while installing the cover and gas springs so I wanted to re-align the mirrors. I thought a neat low tech feature would be to have a remote laser trigger. This would allow me to trigger the laser while I am near the mirrors.

I already had a manual button on my front interface, so I just put a 1/4" mono jack connector in parallel with it. I then put a button at the end of a long cable with a mating plug.
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Yes....my manual power control knob is timing pulley. I did not have a real knob and the pulley fit

I don't think I posted this trick before...

Misumi sells some extruded "slot cover" material. This is a little 'C' shaped piece that snaps into the slots.
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I found that it works great to dress up or hide the wires. It snaps in anywhere so you can start and stop it right where you need it.
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I am working on a new simplified Z lift design. I want to make all the parts out of the same 6mm acrylic material that everything else is made out of. I also want to support it from the frame only. This will make the bottom skin simpler. It will also be much easier to build and adjust.

My first attempt at the design is shown below. This assembly will be the same in all corners but one. One corner will have some adjustment of the idler pulley to allow the belt to be tensioned. The motor (not designed yet) will be in the back of the cabinet. This design looses a little Z travel, but increases the table X/Y size. I think this is better anyway.
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I refined the design to use a few less parts. The motor is mounted on one of the corners. This puts it in a nice location for shortest wiring. The lower right corner has the belt adjustment. This is just the sub assembly view. It mounts to the existing frame. Not all small hardware parts are shown yet.

I think I will laser out some parts and test it.
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I laser cut two parts to test the clamping of the bearing. I think it will work great. I am still thrilled and amazed that the laser is accurate enough to cut a hole that can later be tapped (#6-32) without any clean-up drilling.

This is one of four upper bearing blocks.
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bdring wrote:I refined the design to use a few less parts. The motor is mounted on one of the corners. This puts it in a nice location for shortest wiring. The lower right corner has the belt adjustment. This is just the sub assembly view. It mounts to the existing frame. Not all small hardware parts are shown yet.

I think I will laser out some parts and test it.
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z_lift_2.jpg

TBH I wasn’t a big fan of this design until I realized it allows you to mount the Z axis motor outside the perimeter of the cutting area; now I think it’s great ! Your method of routing the belt is simpler than mine and accomplishes the same belt contact area. I will probably go with a similar design when I’m able to update my Z axis design.

.That looks like a really good design you have made up is it ok if I steal it when you have it all worked out

I fabricated the new Z lift parts. I don't have the correct pulleys yet, so I only put together the motor corner as a test. The parts all laser cut very well. It is a lot easier than routing, because you don't have to babysit the machine as much. With routing there is always concern of a piece of scrap getting itself in trouble. There will also be a piece that rides on the lead screw that attaches to the bed. I will work on that next. I want that to be much more simple than it is now.
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I doubled up on the bearings. This might not be needed, but they are a little narrow compared to the belt. There is a washer between each bearing to make sure there is no stress between the inner and outer races.
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I added one more feature at the last minute that may not even be necessary. Each piece with a lead screw has a tapped hole. This can be used to support the piece against the bottom if it starts to sag. A screw can be lowered to contact the floor as an additional support point. The Acrylic is quite stiff. With eight support brackets, it probably is not necessary.
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Is the Z motor NEMA 17 or NEMA 23?

Z motor is NEMA 23.

I could probably put both patterns on the motor bracket just for the fun of it. I get the pulleys next week. I did not order the belt yet, because I want to make sure everything fits right. I think I might give http://www.econobelt.com/ at try. The belts seem a lot cheaper than Stock Drive. The pulleys are about the same price.

Now that the laser is pretty productive, I might start selling part kits. I think I will start with an 6mm Acrylic part kit for the XY system, a 1/4" MDF part kit for the skins and an Acrylic one for the Z lift assembly. The kits would just be for the parts not available off the shelf. I might see about qty buys from the v bearing people to get the cost down on those expensive items. The cost would be less than you could get it at Ponoko or Pulolu.