Z axis design

[JOE65]

Hey guys:

I am designing a machine that will cut 3/4" MDF (on a low budget).

Here's a pic of my proposed Z axis.

What do you think?

Any feed back would be apreciated.

[CNCadmin]

Not a bad idea but I would add somthing to the edges, the wood is going to wear out fast where it contacts the metal runners. I would use draw slides instead of a channel IMHO.

[WOODKNACK]

what would stop that from twisting from one side or the other? If you want really simple. This is kind of what you got going, Use wood for the sides and put a 1/4 routered slot in both sides. Then use a piece of 1/4" plexiglass for the z axis... cheaper, easyier.

[JOE65]

thanks for the replys guys.

I guess my pic is not clear

The UHMW mounts to the birch ply and that unit slides in the extrusion. I know it seems Micky Mouse but I think it might work?

[CNCadmin]

Ooh that should work, but I think you will have racking problems, unless you keep end play to a min.

[HomeCNC]

You are both missing his idea. I went to lee valley tool to see the channel he is thinking of using. What the picture does not show very well is his UHMW stock that is attached to both sides of the wood. It then runs in the channel on both sides of the wood. The wood will not be in contact with the channel. It should also help to keep the wood slide from twisting as well.
Not bad for a cheap design slide.

[CNCadmin]

I understand completely, but I think it would be tight and would need some slop to make it slide smoothly. Or he will have to use high torque motor's to move it.

[WOODKNACK]

I say give it a try and let us know how it works! I see better now with the picture of the material. Keep us posted!!

[kong]

Not sure if you've designed your x and y, but I found a professional router table idea that could be made cheaply. If you're interested, the picture is here.
Sorry to barge in off-topic, but I'm designing one myself at the mo, and found this to be a good idea.
As for your design, I hear the UHMW is very long lasting, so should be good

[WOODKNACK]

Oh No another "cnc parrot" LOL....
That a good concept, something worth looking into!