Large aluminium profile build

[Boyan Silyavski]

Hi,
Welcome! This will be one quite expensive baby.

Answers:

- the machine should be done so that will do from the beginning whatever will be meant to do. because "later" very soon becomes "never" to lack of time.

-edited: ball screw size 2010 if i was doing that

-70vdc drives for the motors, AM822 and similar digital drives

-steel is 3 times heavier and stronger than aluminum, so design accordingly. Weight is no problem for Z as far as the gantry stays below 70-80kg, 90 at the most, where you will need servos to move that mass reasonably fast
-normally Z axis travel is better achieved when rails move with plate and blocks are fixed. in that case the rails reinforce the moving plate also
if you read my first build from signature, at the end somewhere you will see a correctly made strong Z axis from steel plate and dimensiones. The type i advise, with the moving rails

-if you go with aluminum profile i believe L shape is popular because it offers better stiffness in all directions, plus some other minor benefits you will discover when designing how to mount the pieces

-design the end supports of ball screws so that they have play in all directions and are easy to adjust. bk supports are better for me, as they will not squeeze between them the ball screw

-cheapest and best brand for me VFD in EU is Toshiba, ebay Italy, inverters and motors. Chinese ones work also good.

-HTD 5M 15mm belts is best. min pulley ~20mm, has enough tooth engaged for this job, no less than 18t. calculator Avoid idlers. keep it simple.every element introduces imprecision.

-reinforcing the gantry profile with bolted steel plate at the back or across is better than filling with epoxy. could lead to need of servos though due to weight, so calculate well

-shimming seems best to me in combination with aluminum profiles. everything is possible. you could even straighten perfectly a profile using plastic hammer, DTI and 2m straight edge, if you are good with hammer like me.

-you will need that 2m straight edge, 50cm square, 30cm square, 10cm square. / read my second build log why/



That should keep you busy for a while