Re: 3D printing, powder spreading

Ballendo -
The commercial unit has the single pillar screws; they are bulky
enough and quite solid; almost a 1" screw, IIRC. I would have
simulated that design, as it was quite compact, but a 1/2" all-thread
(that which I had on hand) wouldn't have been stable enough, at least
without additional support, plus, I just wanted something quick, hence
my 4 springs. I left a LOT of border space around it (about 2mm OVL)
but that means the powder drops through and makes it messy....I do get
that on the commercial unit too, so maybe it isn't all that bad!

Personally, I lean towards anything that isn't a single point of
contact - tri or box structures have always performed well in the
past, however synchronizing them could be a challenge. 4 solid guide
rods perma-mounted to the bottom of the build plate, that slide
through bushings in a reference plate at the bottom of the bin, then a
single or double screw in the middle may work. The thicker the
reference plate, or more accurately, the longer the distance between
eh entry and exit points (so it could be two separate reference
plates, separated by, say, 2") would ensure very little slop....hmmm..

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "ballendo" <ballendo@...> wrote:
>
> Ted,
>
> Thank you for sharing this. Helps immensely.
>
> Ballendo
>
> P.S. You mention having single raising/lowering screws. And than
> follow that up with a comment about them being problematic. Would my
> idea (tubed double screws) help in this area, based on your
> experience?
>
>