Back in a sticky spot, finally

 All right, the icicles have finally melted, and I am done cutting expensive foam board into little pieces.  We are back to work and mixing epoxy.  The first items glued together were the solid glass reinforced plastic (grp) side plates that will support the struts that link the main hull to the beams.  As shown in the photo, the thickening rings were glued to the side plates.  Both parts were fabricated a long time ago when I was making the parts for the central mounting modules.  Each piece is approximately 3/16" think solid glass and epoxy.  To ensure the hole in the rings and plates were properly aligned, I ran a bolt through them while the epoxy cured.  The biggest risk in this step was the parts becoming permanently glued to the bolt.  To help avoid this, I wrapped the bolt with a layer of clear packing tape, which the epoxy doesn't stick to very well.  Then I simply cleaned up any excess epoxy before threading the parts on the bolt.  Since these are high stress components, the epoxy mix included some cabosil to thicken and toughen the glue.  I still need to round over one side of the long edge on each piece, as well as a little general clean up sanding, then these parts are ready to go into the beam mold.

I used the left over glue from the reinforced side plates to start bonding the high density inserts into the various pieces of foam that will make the beams.  There are a total of 16 inserts in the pieces shown here.  Although I still had glue left over at this point, it started to kick and got too thick to use.  I only made about 100 mL, combined with about an equal amount of cabosil.  So it doesn't take much epoxy to do this job.  I covered the table with a sheet of vacuum bagging material, which the epoxy doesn't stick to very well.  Then I just pressed the inserts into their openings, squeegeed off most of the excess epoxy, and evened it up on the table.  Once cured, the parts popped off the table with minimal persuasion.  Before assembling these parts into the beam mold, I will sand both sides clean.  Easier and quicker to do the sanding now than when assembled into a complex form with lots of inside corners.

These parts are the foam pieces for the beam sides, including all 72 high density inserts.  I spent the past couple weekends custom fitting each of the inserts so I could glue them in place efficiently.  Each piece is labelled so if I drop the stack I can figure out which insert goes where.  Next good weather day, i.e. reasonable temperature and moderate humidity, I will permanently bond the inserts in their respective cut outs.  Then a little sanding and ready for installation in the beam mold.  I could have installed all of the inserts when assembling the parts in the beam mold, but I figured it would be easier and less stressful to separate the tasks.

I still need to do a little prep on the mold before starting assembly of the foam.  Some of these tasks include drilling holes for screws to hold these parts in place until they are bonded together, and marking and taping the seam locations to prevent gluing the parts to the mold.  Hopefully old man winter has gone to bed, and the spring showers cooperate so we can get on with the fun.