Well, when it rains it pours… seems like I’m clearing out all the upcoming spring mistakes early.

So it was a late night last night.  I got a lot of things done.  And although it was a nice warm day, as par usual over the last week the nights have been chilly.  I set a box with stuff in it (for weight) on top of a stool, with 2 heat lamps attached to the stiff cardboard —both aimed at the micro I had just added onto the right longeron… the temp was low 50’s in the shop, and very likely to get much colder than that.

Well, this morning as I got about 10 feet from the door of the shop, I could smell IT: the godawful odor of burnt epoxy, fiberglass and micro.

This is what I found.

Apparently, one of the light clamps had shifted, and it toppled the box over with the lights “conveniently” face planting right onto the strake leading edge.  My saving grace was the light with the cross grill across front landed on the BL23 junction, whereas the bare light landed inboard on the storage area side of the strake leading edge.

Here’s a look on the inside of the slightly cooked discolored paint.

Well, after opening up all the doors and windows, turning a fan on and letting the shop air out for a good half hour, I then got to work clearing out the charred fiberglass on the outer surface of the strake leading edge (pic 1).

The burn was very localized to the heat lamp face, and the glass beyond the burned glass was fine… and still very strong in that I couldn’t push it in at all.  The internal foam had melted away about 1/2″ to 3/4″ from the edge of the hole.  The brown stuff inside the hole is the melted foam and micro attached to the inside glass.  I then took my Fein saw and cut the perimeter of the hole at a shallow angle for the upcoming glass repair (pic 2).

To ensure I had “aircraft quality” foam reinforcing the edges of the hole, and as internal dams for the pour foam, I cut 3 blue foam wedges and micro’d them into place (one each side and one on the bottom).

I also discovered a slight delam area between the glass layers on the outboard side, so I cut the exterior delammed glass away.

As the micro’d foam wedges inside the hole of the burnt leading edge spot were curing, I then finished adding micro to the corner junction of the left longeron to left strake.  Here is the front side.

And along the aft side.

I also added about a foot more micro to the front side of the right longeron as well, just beneath the canopy lip edge.

I added pour foam to the inside edges of the burn damaged leading edge of the right strake.

After the internal perimeter pour foam cured, I cut the foam flush with the hole opening, made up a taped cardboard dam and secure it in place with more duct tape (pic 1).  I then whipped up some pour foam and carefully poured it into the dam and left it to cure (pic 2).

After trimming and sanding down the added pour foam (pic 1), I prepped the foam with wet micro before laying up 2 plies of UNI that crossed each other at a 30° bias (pic 2).

I then peel plied the layup and left it to cure overnight.

Tomorrow I’ll add a final ply of BID over the UNI and call the repair good, requiring only more micro finishing at that point.

If you’re curious about the BL23 junction leading edge heat damage, it merely cooked some micro and caused some minor surface cracks. I chipped away the cracked micro to clean it up.  I guess lucky for me the BL23 junction required a bit more (aka thicker) micro to blend it in, so the underlying glass was completely unscathed.

I also added some micro onto the aft nose/avionics cover’s aft corner inside BID layups before then adding a ply of BID on top of the added micro.  I then peel plied the layups and left them to cure overnight as well.

I then shot a quick video showing you the proof of concept testing I have been working on with the wire-manipulated micro-switch block for the canopy latch internal lock lever.

And with a crazy, frustrating day under my belt, I called it a night…