Simple Machine (help and advice needed)

[EddyCurrent]

Yes, that's a better design.

Only problem i envisage is the alignment of the gantry rails, do have a solution to this ?
Regards
Mike

You are right, maybe one rail could be welded and the other bolted to allow adjustment ?

[Gregor]

Hi
When you talk about the gantry rails are they the rails on the x axis,Heres a few new pics ,I have done all the metal work to scale on sketchup and the dimension's off the base are 860mmx720mm not including the end plates on the base. The gantry was made 730mm to allow for clearance for the plates for the ballscrews. As I say I want to try and make it as simple and easy to make with most off it made by welding so let me know if this design is a load off Cr@P
Cheers

[EddyCurrent]

Hi
When you talk about the gantry rails are they the rails on the x axis,

Well I assumed mekanik was talking about the Y rails, those actually on the top and bottom of the gantry cross beams.
Are you putting the Y ball screw between the two cross beams ? if you are it's been suggested to add a plate to the front to keep crap away from the screw. This means putting a slot in the plate to allow the bracket where the ball nut attaches to the Z axis to move across. like here; http://www.mycncuk.com/threads/6418-...8048#post48048
It also adds strength to the two cross beams.

[mekanik]

Yes the Gantry rails, top one can be leveled as per the X axis ie with epoxy but you then need to align the bottom gantry rail to the top one.

[Gregor]

Good point Mekanik I don't have an answer to that I hope someone will read this and know how to do it. EddyCurrent I don't have anything to cut a slut but I could weld some 3 or 4mm plate on like in the sketch

[Ross77]

If you get the 4way loading bearings then it is best to mount the rails on the front face of the gantry and means the z axis mount is simple plate as well.

You only need to mount the rails top and bottom if they are the supported rail type due to the unequal load capacity of the open bearing.

Your triangulation needs to go from one node to another node (connection) or else to will place a bending moment in the middle of the beam. :0)

[Gregor]

Hi Ross thanks for the advice
Could you explain what you mean when you say triangulation needs to go from one node to another node please
Cheers

[EddyCurrent]

You only need to mount the rails top and bottom if they are the supported rail type due to the unequal load capacity of the open bearing.

One advantage of the top and bottom mounting is that the Z axis can be closer to the gantry, i.e. less overhang of the spindle.