Made of aluminum, Made for aluminum: Would love design critique!

[gamingan]

Thank you all for the incredibly useful suggestions; learned a lot by trying to think about why each of those suggestions made sense.

I've refined the design now (along with some significant changes in overall geometry) -- let's see if you guys like it.

Here is the 2nd version of the design...

Front view: http://i.imgur.com/Ik9s7uV.jpg


Back view: http://i.imgur.com/iKuChuA.jpg


Below are the changes I made:

1. Most important of all, altered the geometry so that the rails and ballscrews are protected. This also simplified the Gantry side plate design a lot!
2. Gantry side plates now are 20 mm thick (instead of 15 mm).
3. Strengthened the X-axis (i.e., the horizontal "gantry axis") by using 80 x 160 mm aluminum profile instead of 40 x 160.
4. Replaced ballscrews with 20 size (instead of 16), and linear bearings + rails with HGH20 size (instead of HGH15).
5. Added a fixed bearing block (with AC bearings) for Z-axis ballscrew (previously it was fully floating beneath the shaft coupler).
6. Added two more linear bearings (HGH15) for Z-axis.

Feedback?

I hope this one is OK to start assembling!