I started off today by mounting the original wood piece that I used to mock up the foam insert for the headrest “floor” as a temporary glassing base.  Since its overall dimensions are smaller than the overall dimensions of the entire bottom of the headrest, it will allow the glass to overhang the foam while curing.

I drilled a pilot hole into one of the rear hard points and the temporary base, then mounted the base with one screw to the bottom of the headrest.

With the temporary base complete, I was ready to get to laying up some glass.  I did one final vacuum of the surface and mixed up my epoxy with about 2/3 slow with about 1/3 fast hardener to give it about 4 hours until it was solidly cured.

I microslurried all the foam & then proceeded to glass the entire exterior of the headrest’s 4 vertical walls.  I started with about a 1″ overlap on the rear face, wrapped 1 ply of BID all the way around the headrest and ended up on the corner where I started.  This of course gave me a 1″ overlap on the glass.

I then did the same thing on the opposite corner of the rear face, only going in the other direction.  Since the blue foam is a little softer and less dense then the yellow foam, I decide to give it all the extra “hangover” plies to give a essential provide the majority of the rear face with 3 plies of glass, with only about a 3/4″ strip near the center of the rear face being left with only two plies.

When I was done with the actual glassing, I peel plied the entire layup with one piece of peel ply (technically I needed one extra small triangle of peel ply to cover the top rear corner, as you can see in the pic above).

With the layup looking good and the glass edges trimmed back to about 1/4″, I set the heater facing it (on low) and let it cure overnight.

Today I finalized all the prep for glassing the headrest.  While I’ll still need to glass the GPS antenna puck cover, once I finish this next layup the majority of the glassing on the headrest will be complete.

I had deformed the blue foam a bit at the top of the headrest when I was using the heat gun to better align the headrest.  The heat gun worked but, as often is the case, not without collateral damage.  No worries.  That’s the great thing about composites: with just a little more time, you can fix nearly every mishap that may occur along the build process.

So to fill in the significant imperfections I used a page out of Chrissi & Randi’s (aka “The Cozy Girrls”) build book and employed some Super Build Micro!  I actually don’t know what they call it, but I needed a catchy name to set it apart from just plain-Jane micro.

First off, be forewarned that this micro is nothing more than filler & is merely used as very light matter to occupy space.  It is NOT meant for anything requiring structural strength.  If done correctly (and mine was just so-so) it is reportedly really easy to SAND, so you don’t tear up sensitive foam whilst sanding hard cured micro.

How is it made?  What’s the secret ingredient you ask?  Well . . . it’s . . . ALCOHOL.  I mixed up a batch of really thick micro, then I add a little bit of rubbing alcohol, then that re-liquefies the micro paste into micro slurry, whereupon I added more micro until it was really thick paste again.  Then a little bit more alcohol, then some more micro, etc.

Obviously what you get is a product analogous to auto paint in that it is laced with a reducing agent. As the paint cures, the reducer evaporates and lets the paint solids cure into a hard shell. In reality, this is more along the lines of what happened with this micro. The build micro is supposed to be easy to sand, but although it did sand easily enough to keep me from tearing up the foam, it was still a bit of a chore.  It probably took about an hour total to sand all the micro to the shapes and levels I wanted.

Here’s a pic of the build micro applied to the areas needing it on my headrest.

And here’s a picture after I sanded the excess micro and shaped it to match the shape of the headrest.

Here’s a side profile view of the top aft corner that was in such a bad way before I started.

With all the holes & dings filled and sanded, I finally had the headrest ready to glass.  I had used only BID scraps up to this point, but I wanted a nice finish for the headrest tower with no overtly noticeable glass seams, so I used my new glass cutting table for the first time to cut 2 pieces of BID out.

My plan is to glass 2-plies of BID on the front & sides, and then have all the overlap/extra plies ending at back of the headrest.

I cut 2 BID pieces 13″ x 23″ in the ballpark of a 45° bias for strength.

With the headrest ready for glassing and the BID waiting to be applied, I’ll tackle this decent-sized layup tomorrow since it’s getting late.

Today I cleaned up the layups on the headrest base piece and the GPS antenna shelf.

One issue I needed to address is that the front face of the headrest was a little off from straight vertically.  With the headrest on a flat surface, using a square I could clearly see that it was a few degrees less than 90°.  After a bit of head-scratching, I decided to simply add a few layers of BID to the front third of the headrest base, in a stepped fashion.

As far as the antenna shelf, I added hard points for the front screws, but the rear screws are actually located right on the edge of the antenna shelf insert that I just glassed.  So I Dremeled out the foam in about a .6 inch diameter half circle for each point where the rear screws go through.  I mixed some flox up and poured it into my prepared foam edge hard points.  Since I had extra flox leftover, I filled in the remaining gaps around each of the 3 threaded inserts for the RAM ball mount.  You can see this in the pic below:

Stay tuned, much more to come . . .

Today I focused on tweaking the shape of the headrest tower to get it as close to symmetrical as possible.  Because of the design, it’d actually be somewhat difficult to see my slightly lopsided headrest assembly.  Nonetheless, I still wanted to get everything as balanced as I could.  I spent about an hour sanding the tower and was pretty darn happy with how the symmetry came out.

With the shape locked in, I worked on the GPS antenna puck shelf to install the hard-points that will keep the GPS antenna nice and secure.  As you can see in the picture below, I had 2 pieces of 1/4″ plywood marked off and cut the first one no problem, but when I cut the second one, it flew off into the bowels of the garage, not to be found no matter how much cussing and moving things around ensued.  Thus, I grabbed the next piece of plywood available, which was slightly smaller than the other one.  In my mind, here’s where NOT sweating the small stuff comes into play.  Thus, to save time, material and frustration, I simply embedded different sized–albeit capable–pieces of plywood for the hard-points.  I’m sure stuff like this drives the OCD’ers crazy, but that’s why I revel in not being OCD!

My next task of the evening was to embed 3 threaded aluminum bungs into the back of the headrest to attach a RAM ball mount for the GIB.  I climbed into the back seat to get a good idea of what level the RAM ball mount should be attached.  Once I had that info in hand, I set about setting up the RAM mount to install the threaded aluminum bungs.

I started by cutting the 1 inch long aluminum threaded inserts (ala the Cozy Girrrls) in half since the foam is not thick enough to allow for the full length of a standard insert (aka “bung”).  After cutting them, I prepped the RAM ball mount by wrapping it with packing tape.  Once protected from the flox I would be using to hold the threaded aluminum inserts, I made 3 holes into the foam down to the opposite-side glass.  I then screwed the bungs to the RAM ball mount securely.  After mixing up some flox, I poured it into the 3 holes about halfway, then I embedded the 3 bungs attached to the RAM ball mount into the flox and let cure.  Below shows all this post cure.

And with the ball mount placed to show the final spacing.

Today I took all the clamps off the cured headrest box.  I will state for the record that building a complex shaped box without the use of jigs may have quelled my inner artist, but it didn’t make for a perfectly shaped box.  Not bad, but the sweep (or swoosh!) on one side of the box from the front corner is slightly different than the other side.  A symptom of having glassed the front face to the rear part of the box one corner at a time.

Anyway, I tweaked it with a myriad of clamps and will work on it just a bit more to massage the shape.  Regardless, here’s a couple shots of the completed headrest box structure.  Note that the top shelf insert for the GPS puck is just wedged into place and not glassed yet.  I will need to insert some small hard-points for the GPS puck screws to be fastened to.  In fact, in the second pic you can see the markups I did for the puck screw points & cable access hole.

A couple of days ago I showed a pic of my glassing the foam for the GPS puck shelf and the headrest base, which I shaped to size below.

This headrest base–made of 1/4″ foam–would prove to a trooper that fought valiantly to stay in the game, but alas, it succumbed to the intense heat of my heat gun and warped as I was bending the headrest tower to my will.  As I hunted around for some more material, I ran across a scrap piece of 3/8″ Divinycell foam that was already glassed on one side.

Moreover, since I had ginned up a base mock-up out of OBS flooring board, I was already in the frame of mind for something just a tad thicker and robust than the 1/4″ foam base. After playing around with the shape for about half an hour, I transferred the actual wood base mock-up outline to the 3/8″ foam.

I then cut out some small square hard-points out of the Finnish Birch 1/4″ plywood that is used for the firewall, etc, after I decided where my headrest attach bolts will go.

I floxed the plywood hardpoints into the holes that I made in the headrest base, and then covered each piece of plywood with about 12 plies of BID to fill up the remaining 1/8″ of space so that the hardpoints would be even with the face of the foam.  I then laid up 1 ply of BID over the entire piece of foam & peel plied it.

I set the headrest base aside to cure overnight and called it a day.

I guess here would be a good point to digress & explain why I have bolt hard-points in the base of my headrest.  It all stems from the design of my 4130 steel rollover assembly, or simply the roll bar.  Since the main roll bar wraps around the back of the headrest tower, AND the front 1-3/4″ of the headrest tower actually sits on the rollover crossbar, there’s no way to hard glass the headrest to the base of the pilot’s seat and still have the rollbar removable (which is a design feature I would prefer to have)… since they’re interconnected.  A bolt-on headrest also allows for much easier future mods (if I decide to make any).  Or I can replace the whole thing with a super swank version later on if I so choose!

Tonight I razor trimmed pieces, pulled peel ply & cleaned up the peel ply strings from the headrest layup.  After the layups cured, I was left with 2 assemblies: the front piece and the two sides/back wall as one unit.

I then dry fitted front to right side wall assembly… doing one side at a time to minimize complexity.  I drilled holes for nails and preset those before glassing.

I then mixed up epoxy, micro’d the front wall piece to the right side wall piece, set with nails, cleaned up the exuding micro & then taped up the joint tight.

I used fairly thick micro paste to fillet the corner, and then pre-pregged 1 Ply BID corner tape just a hair under 2″ wide so it would fit under 2″ peel ply tape.

After the corner was laid up I peel plied it with the 2″ wide tape.

I also rough measured, cut & laid up two 1/4″ foam pieces with 1 ply BID for the headrest base and GPS antenna shelf.  I threw some peel ply on these last pieces and called it a night.

I started out today by picking out some good BID remnants for the layups on the interior surfaces of the headrest.

I then commenced to laying up 1 ply BID on the inside of the front face of the headrest. Since I’m not sure what all I’ll be glassing to it, I went ahead and peel plied the whole thing.

I had thought about just doing all the pieces separately and then assembling the headrest, but I thought since is my first real layup in almost 2 years, why not make it a little more challenging & interesting by laying up the 3 interior sides at once.  So I micro’d the 2 side pieces to the back piece and held them in place with wood screws.

I used micro paste to fillet the corners and then laid up 1 ply BID inside the resulting “U” channel.  After the glass was wetted out & looked good, I peel plied all the edges.

Step 1 of the headrest complete!