8 x 4 build

[D.C.]

Have you a read through this build log? Lots of renderings at the start and photos of the frame later on that might help.

http://www.mycncuk.com/threads/6619-...2060#post52060

[Clive S]

do you mean ball screws? if so then yes both sides :) using nema 34 motors and servo drivers.

cheers

ash

Ok then have factored in the whip of the screws at that length etc.

[reefy86]

hi clive, what do you mean have factored in the whip?

cheers

[Clive S]

hi clive, what do you mean have factored in the whip?

cheers

Ball screws have a critical speed that you can reach before they start to whip I am not an expert on this but I would have thought that if you are using screws that long you might need rotating ball nuts. Do a search on here there has been plenty of talk about it.

[kingcreaky]

i used rotating nuts, on my 8x4 build because of the whip effect Clive mentions.


skip to about 1:15


http://www.mycncuk.com/threads/8242-...t=wall+mounted

[reefy86]

thanks guys i will take a look :)

[reefy86]

i want to hide my z axis stepper motor rather then having it stuck in the air so it requires a belt and pulley, is there a requirement to which i should aim for? more teeth the better or the opposite?

cheers

ash

[Blackrat]

i recommend to brace the legs with the diagonals , not the way it is now, there is no force pushing on the braces on that orientation

:)

[reefy86]

think this maybe my final design on the frame, what do you think?

cheers

ash

[Lee Roberts]

I would suggest you don't need the flat bar as it's not likely to add anything, where you've got the angled sections on the "feet/legs" of the frame, move those up into the rectangular spaces or add some there, they will serve you much better.

.Me