Quote Originally Posted by JAZZCNC View Post
Looks ok to me and will work fine. Thou I've got a few suggestions which will make it a little stronger and easier to setup etc.

The height of the gantry doesn't look very high so you could change it a little and gain some height while increasing the strength and making it easier to setup.
I would make the gantry and bearing plates two separate items. Make the Bearing plate and the drop bracket for ball-screw one part. Then use another plate bolted directly to the profile from the underside and into the shortened gantry sides, this will stiffen the gantry a little. Then bolt this to the bearing plate because how you have it now will make accessing the bearing bolts difficult. But also it allows you to square up the gantry without affecting the ball-screws.

As you have it drawn now then if you need to adjust the squareness all you can do is loosen the bearing plate and rotate the gantry as a whole. This then changes the alignment of the gantry sides so they are no longer parallel to the ball-screws, this, in turn, means your ball-nut mount unless shimmed, etc puts a twist on the ball-screws that causes binding and premature wear, etc.
If you do it as described above then you can just loosen the gantry without affecting the ball-nut alignment. The extra bearing plate also adds a little height to the gantry, It's also very easy to add extra height if ever needed.!

Simple changes which will make a big difference to the machine setup.

Edit: You could also gain back some of the lost travel by making the Gantry plate a little longer than the bearing plate and offsetting the gantry back a little.!
Thanks Jazz, some great suggestions. I am not sure that I understand 100%, do you mean something like this? (sorry, really crude drawings just modded from my originals so ignore hole placement etc.):

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The red plate fixes to the gantry profile from below and the gantry plate, the gantry plate fixes to the gantry profile in the usual way (and also to the plates on the back of the gantry that carry the BF/BK blocks for the X axis ballscrew). The red plate can then be fixed to the bearing plate and if I either elongate or slightly oversize the clearance holes I can get some adjustment for squaring the gantry assembly.

Am I on the right lines with that?