So, if any of you haven't done this yet - two pieces of advice:
Tip 1 - Don't assume if you get a great fit on the forward part of the wing tip (i.e. it fits super tightly on the forward curve of the wing) that it will fit or be a peachy fit once it is tight with either rivets or nut plates/screws.
Make sure above all else that the tail edge aligns with the aileron when it is set to it's "in trail" position with the stick you made to align the ailerons properly.
If you didn't do that (my original one was wood) I'd go to the hardware store, get some cheap straight aluminum yard sticks, and match drill those to the specified tooling holes in the tip wing rib.
There is a *lot* of wiggle room with the tip trailing edge if it isn't nailed down. Use that flexibility to get a great alignment with the aileron, then working forward alternating top and bottom match drill to the skins and cleco it down.
You'll probably have a fairly close fit to the forward skin, but the aft part is by far the harder to move after the fact, especially after you've installed the ribs. The imperfect fit forward is easy to fix with micro or Superfil.
Once the ribs are in the trailing edge is nearly immobile.
Tip 2 - go lightly with the trimming around the aft edge where the aileron hinge brackets are - it's very easy (I did it) to over trim then have to rebuild the skin to get a good fit.
If you do foul either thing up like I did (I went for the tight fit forward idea) flox is your friend. I'm using nut plates and had to drill them all out and fill the holes with flox. Worked great. Actually seemed to be as strong as the tip glass.
Some pics
Getting ready to do one of the elevator tips.
Didn't have to trim it much - I just hit it with my hand held belt sander to get it straight and to clear some of the rivets.
Had to trim it just a bit at the back because it tapers to a point.
This is when I was first putting in the nut plates thinking that a great fit at the front would guarantee a great fit at the back. Here's hoping you get both - surely someone must get lucky every once in a while.
And this is after realizing that I couldn't get both, so I'd drilled them all out and was getting ready to flox them. Epoxy sets up great on a warm day. :)
Holding the elevator tip tightly to the tip for match drilling.
Match drilled and dimpled and checking the fit. I just did the dimples with my hand deburring tool.
Nearly done riveting it to the elevator.
Flox after curing and a boatload of sanding. This is some seriously tough stuff.
Close up of the sanded flox. It's transparent, but hard as nails.
Back side of the floxed holes.
Match drilling the wing tip rib to the tip. I put mine in a bit further than the plans called for (maybe 1/8" or so). It fit better that way.
Making sure everything lines up and the trim lines are all correct. A lot of putting on and taking off of the rib, the tip, and the aileron to get it all right.
Working on the horizontal stab tips. For mine, I found a curve gave a much better fit. I was actually able to put the elevators on then trim the tips close to where they needed to be and put them on over the whole thing. Made finding the final trim lines easy. I'll spot clue some pink builder's foam in the hole, then glass over the top of it, and melt the foam out with acetone (got that tip from a Velocity builder friend).
It's funny - nearly done with the project and finally got a rivet fan. Needed some bits from the Yard Store and decided to get one. Would have saved a lot of time. Using it to lay out the holes for the tip rib made it extremely easy to get good spacing.
Making a mess working on various things at the same time.
Contrary to the plans, I drilled my interior rib to the skin before I epoxied it in there. I couldn't find a good way to hit it drilling blindly. What I did was use the fan to lay it out, drilled it on the table, then put it in place and used my right angle "tight fit" drill kit to back drill to the wing tip. Then I scuffed everything, floxed it up and used a couple of clecos to keep it in place while it all cured. Easy to drill through the holes after it's cured, countersink and rivet. I was pretty happy with how it came out.
