002 :: Z-Axis test run (not good)

So ok, some of you know, i am making a rather large 3d printing machine, totally from scratch, so today i think i will just experiment with this blog thingy and update some thingy from this thingy that i have been doing. i hope some of you like thingies.

This part of the machine is the Z-axis. it is based on 4 threaded stainless steel rods to move a large attached platform up/down. the platform will sit the Y and on which will sit the X axis (motors and all, like a CNC style)

This method is quite challenging especially if you add on to it by using cheap materials.

The threaded rods are not professional CNC machined type, they are your hardware store stainless steel rods, with the extra machined ends to fit bearings. they are NOT CNC standard straight and all. they wobble on first try, they had to be manually bent into something ... not so wobbly.

Parts of the gantry are wood, as it is experimental, there will be tons of snapshot changes and wood is a rather fast subtractive medium to work with. however some pieces are pre-warped too, adding some interesting gradients to the intended levelness of the frame.

The alu profile was a last minute addition to enable a section of the frame to be able to slide and hence adapt to the length of rods/bearings in a easier fashion. it also helps in the eases of taking things apart when changes are needed.

The pulleys attached are done in a rather quick way, and their bores are not fitting. hence you can see the terrible wobbling effect. there were some fillings in the gaps but they are not permanent stuff and it gave way quite soon. wobble wobble darn!

The belt in use is a XL size, driven from a smaller pulley to a larger. they are gotten from B&B manufacturing. http://www.bbman.com/ .somehow they are more helpful than SDPSI and quick emails fired around makes quick decision on what options i can use on this Z frame.

I assume that the stepper is fully primed to deliver its nearly full torque, however it is discovered that it is a little on the weak side and so a new NEMA23 will be coming in shortly to try out some new higher torque runs at a later time. the stepper being used is a higher voltage Sanyo_Denki_103H5208-10U41 rated @ 42Ncm (9v/0.85A). the NEMA 23 coming in for next test is rated @ 120+Ncm, there was also an option to try a 200++Ncm NEMA 23 (prolly even later).

The reason why this little NEMA17 failed is because the rods are not CNC balldrive rods, they have alot of friction in them inherently (so nope they are not baby smooth). the rods are quite badly scratched on the threads, kinks and nooks, but they are cheaper than the usual CNC balldrives by a factor of about 4x for the same size (infact, i wasnt able to find 1 ex-stocked in that size, 1000mm length. my estimates will put a section of that to be in the region of prolly USD180 bucks)

until the next update, keep your hotends running!

cheers yall :p

*edit* post 024 updated

(so ... of course, this machine did'nt work, the wobble makes it really bad)