Sunday, July 31, 2011

New build platform

I had reservations about the suitability of my original MDF (6mm) build platform and this past week proved it wasn't up to the job. With my latest extruder incarnation working consistently I was ready to start laying down some plastic, but no matter how much I fine tuned the level there was inevitably some part of the surface that was too high or too low. It proved too much of an obstacle so it had to go! I'm also dubious about the four-point spring loaded levelling approach that's in common use but reworking that is for another day.

I got lucky in my junk collection and dug out a 12mm thick rectangular piece of Perspex (acyclic). What ever it's previous use, it had four domed rubber feed, nicely positioned, one in each corner. They were threaded in place which made them potentially ideal should I need to level the new platform in any direction. I figured it had sufficient weight on it's own to not need much bolting down, so I came up with the following way of positioning it on the Y-buggy.

Above you see the 12mm thick Perspex and it's rubber feet. I've put blue-tape on the top surface.

To seat the new build platform on the Y-buggy I cut a "H" from some MDF and bolted it down (no adjustment). I drilled cone shaped holes using a large countersink bit, in each corner, in positions corresponding to the feet on the new Perspex platform. Then I simply sat the platform feet in to these recesses. It's own weight held it in place. See below photo of my new build platform in place!

Initial alignment testing, by moving the extruder to various locations, showed this new arrangement was much more satisfactory, even without any adjustment of the feet. I tweaked two of the feed a tiny bit and away I went. I laid down a test print with a raft and it took to the surface nice and evenly!

The added bonus is that the platform can be easily removed, and returned, if desired, without any apparent impact on it levelling.

Next post is on how well the printing has in the past week... It has gone well as hinted in the above photo! :)

Thanks for viewing!
No.6