Sunday, March 25, 2012


The work on this plant was actually done a few weeks ago, but with the paper modeling distraction I'm just getting caught up with the posts on this build, and should move right into current modeling on the structure.

Again, work is starting with the construction of the batch plant portion of this mill.  The batch plant has five 26' diameter concrete storage silos and one almost half that.  The silos hold sand, soda, lime and other materials.  Since this is a mostly steel mill modeling page, a good comparison would be the high-line at the steel mill, with a slight difference.   A steel mill high-line has bins for the various materials - coke, limestone, and iron ore - they are loaded into scale cars that run beneath the bins, where they are weighed, moved to the skip hoist and discharged into the skip.  The glass batch plant has a similar scale car running underneath the silos collecting the various materials, however, this car also serves as a mixer, combining the right portions of each material required for the "batch".  In a steel mill the materials aren't combined until they fall into the blast furnace.   At a glass factory, a pre-mixed "batch" has to be used to feed the furnaces.

Foundation with two styrene wraps
The foundation/mixer car run for the prototype is basically concrete cylinders, slightly larger in diameter than the silos.  I tried taking the same pvc pipe that I used for the silos, slitting it, and then adding a piece of styrene to increase the diameter.  This worked somewhat but I wasn't 100% satisfied with the results.  So I ended up wrapping the pvc pipe with two layers of .040 styrene.  A clamp was needed while the glue dried - the seams were staggered slightly and will end up where the silos adjoin so won't be visible.  This was harder than is looks.

I then took the five large foundation pieces and the smaller diameter foundation, also wrapped,  and glued them to a sheet of .060 styrene, roughly cut to the diameter of the cylinders.
Top finished
It took a lot of carefully cutting and sanding to clean up the foundation top. You will notice I also added small flat strips between the cylinders on each side to create the subterranean mixer car run.

With the vacuum formed tops glued on and the silos temporarily set in position.
The results are encouraging.  Note that I did have to adjust the height of the smaller silo a little to get the roof peaks to line up - they all have a 30 degree pitch, but since the diameter is less the rise of the roof is correspondingly less so the silo is taller.  I was close on my initial cut - off by maybe one or two scale feet.


Chris Crook said...
This comment has been removed by the author.
Chris Crook said...

Do you have any pictures of your prototype? I would be interested to see them.

Jim Musser said...

Sure Chris - stay tuned - I'll make sure I post one in my next post on this project.