Fiberglass requires a different kind of workday structure. You have to be willing to spend hours and hours prepping, masking, applying, and waiting for the stuff to dry, only to sand 90% of it off and then go back with round 2 and 3 to fill in mistakes, low spots, whatever. So tis week has had a lot of that. In the down time waiting for stuff to cure I occupied myself with various small tasks like working on instrument panel placard templates, dimpling holes in the empennage, rigging elevators, stuff like that. I'll do a different entry for those things, but thats why you may notice 2 or 3 different entries all on the same date. There really wasn't much value in posting something that just says "sanded for two hours today" In some of the pictures below, the fiberglass is obviously not finished to a showroom quality paint job. The intent here is to have it structurally sound and aerodynamically smooth, with scratches and pinholes taken care of and a coat of cheap primer applied to protect it from u.v. and other random environmental stuff while I'm in flight test. Thats why you'll see obvious tape edge lines in the primer on the elevator counterbalance tips, for example. Anyway, over the past week in the fiberglass efforts I finished the empennage tips. You may recall from a previous entry that I had used foam plugs as part of the process. On the h/s tips, once I disolved the foam out I had to fillet some flox into the back side to give the structural bond some depth. By the time I did the v/s tip, I had realized that I could cut that fillet space into the foam plug and just fill it in from the front as part of the initial layup. This eliminates a step and saves quite a bit of time so I'm detailing it here in case anyone stumbles across this in the future. I also finished the empennage intersection fairing to an airworthy state. What I mean by that is that finished adding back in the 1/2"-3/4" that I had mistakenly cut to short along the front edge (don't cut to the scribe line!), sanded it all smooth, and applied a coat of hi build primer to protect it from u.v. It's fitting pretty well and I'll fly it that way and then let the painter do his thing to make it perfect. While in fiberglass mode, I also attacked something that's been bothering me for a while. I've seen lots of flying RV's where the trailing edge of the wingtip extends about 1/4" or so aft of the trailing edge of the aileron. Fine from an aerodynamic standpoint, but I just find it annoying that you work so hard on something and it visually just doesn't line up. The obvious fix for this is to fly it, make sure you don't have to squash an aileron to account for a heavy wing, and then once the ailerons are 100% for sure where they're supposed to be, mark the tips with a straight edge and trim them to match the rest of the wing trailing edge. The problem with this plan is that where the top and bottom of the wingtips meet at the trailing edge, it's a very acute angle. Vans has dealt with this by building up a structural fillet in there thats presumably flox or something, which is only about 3/8" front to back. If you cut off a bit of the trailing edge, you're going to cut into that structural bond, reduce it's footprint to the top and bottom surface, etc. I thought about is for a while, and debated whether to just live with it as so many others have, but ultimately decided it was probably worth the effort to at least give myself the option of fixing it before paint without having to take a bunch of stuff apart. Not a lot of pictures of the process, but I removed the wingtips, which were just clecoed on, cleaned out the trailing edge joint plus scuffed it up to give new epoxy something to adhere to. Because ether angle is so acute, access is limited and there were lots of sandpaper on a ruler/scotchbrite on a coat hangar wire in a drill motor/acetone rag on a stick type operations. Once prep was done, I stood them up vertically with the trailing edge down, taped off the open inboard end, and poured the trailing edge full of a layer of epoxy/flox about 1/2" deep. I then topped it off with a ply or two of strategically placed 8oz cloth which adds ears that bond to the inner upper and lower tip surfaces in areas where I was able to reach with more conventional prep methods, so I'm 100% confident that if the bond between new epoxy and 17 year old wingtips ever breaks loose down in the pointy tip, the whole thing is bonded in at least a couple of places over a wider surface area and is physically too big to slide inboard and interfere with the ailerons. This now gives me the option of cutting down these trailing edges to match the ailerons while still having lots of structural element in the trailing edge. I have found that a big part of fiberglass efficiency is planning your work flow into a logical sequence. One of my wingtips had been banged into something before I bough it and had a chunk broken off the corner, so I did the inside of that one first, then the next day I cleaned up the broken corner, drilled a couple of #30 holed through it into the new epoxy on the inside, then when I was applying flox to the inside of the second wingtip, I was able to use the dregs from that batch to build back up the damaged area on the outside of this tip with a flox mixture that penetrated all the way through into the new stuff thats as laid up the day before.