Z Axis appraisal please

[Boyan Silyavski]

Why don't you use steel profile gantry? Or at least steel profile and aluminum profile mix if you insist on using aluminum profile? Profile is much stronger than plate. It would be good idea to check your design with the calculator posted in the sticky area of the forum. Personaly i dislike plate sides of gantry if they are not double, imitating profile.

[EddyCurrent]

Ah ah I find this hilarious.!! . . . For some reason you don't like the screw at rear but yet your happy with the rear plate extending down below gantry and flapping about seriously weakening and compromising the quality of finish.?

I mentioned this in my post because I knew it was crap but I'm changing it now.

Think about the machine your building not what some spread sheet that somebody who's never probably built a CNC machine predicts is the optimum location, Or from looking at some poorly built machine who's getting less than expected results then blaming there crappy build quality on design style.

I agree but I like the look of this design better anyway

Your insistence on keeping Z axis slim and low is seriously compromising the machine.!! . . . Front or rear screw no matter but this Z axis is wrong.
Lift the bearings and rear plate so they are supported by the gantry other wise the back plate will flex under cutting forces.!

Same as point 1

What happened was I was concentrating on the top bit and forgot about the overhang until I posted the pics and saw it.
Also moving it to a Build Log next.

Thanks for comments.

[EddyCurrent]

Why don't you use steel profile gantry? Or at least steel profile and aluminum profile mix if you insist on using aluminum profile? Profile is much stronger than plate. It would be good idea to check your design with the calculator posted in the sticky area of the forum. Personaly i dislike plate sides of gantry if they are not double, imitating profile.

I was thinking I might add a 12mm plate to the flat back side of the gantry to tie it all together. I know some designs have double gantry sides but I'm conscious of the gantry weight and also feel the depth of the gantry cross members will prevent any flexing of the sides. But I may be wrong !

Thanks for your comments

[Boyan Silyavski]

I was thinking I might add a 12mm plate to the flat back side of the gantry to tie it all together. I know some designs have double gantry sides but I'm conscious of the gantry weight and also feel the depth of the gantry cross members will prevent any flexing of the sides. But I may be wrong !

Thanks for your comments

I assume your gantry will be 160mm high, that means for the 600mm travel you will use something like 1m of 160x12mm plate which weights 15kg. For example 1m 160x60x4mm steel profile weights 9 kg and would be stronger than your combined plate+aluminum profile.

[EddyCurrent]

Continues here

http://www.mycncuk.com/forums/router...eady-eddy.html