Re: Why ballscrews for linear drive?

Very good advice. However, there are complications.

1. This will ultimately be seen up close and personal by members of
the public first-hand walking through it, not just on screen or on
stage.

2. It has to take down into pieces small enough to fit into a van and
may be put together and taken apart by people who've had little
instruction in doing so. So the only connections between the two
halves and the top and bottom doorframe must be simple and easy to
disconnect and reconnect.

I may very well end up doing this only with separate motors and such
for each door. I know I'll end up getting some of the sliding
mechanism from the hardware store.

Thanks,
Steve Greenfield

"Carlos Guillermo" <carlos@v...> wrote:

> Steve -
>
> Why, oh why, do they need to be ballscrews?? If you're looking
> for simple and cheap, try this:
>
> 1.) Go out and buy a set of closet doors and hanger rails from
> Home Depot (paint /decorate/replace doors as desired). Choose a
> long enough rail (or two rails) so you can put both doors on the
> same track and open fully. Don't forget to use guide brackets for
> the bottoms.
> 2.) Mount a 1-2" dia. pulley between bearings over the top-middle
> of one side of the tracks
> 3.) Mount a direct drive, or slightly geared (backdriveable, if

-snip-

> The result of this is that, with one motor and one belt, the doors
> will travel in opposite directions, and it should only cost a few
> bucks. This should work fine, if all you need it for is a stage
> prop?