Latest photos at the bottom of the page
This page shows the re-finish of the outer ailerons and the addition of the mass balance required by Schempp-Hirth Technical Note (T.N.) 286-27 "Wing-Tip Extensions for a span of 25.5 meters". I need to add a few kilos of brass to the ailerons to comply with the new mass balance requirements of the wing. I must also insure the ailerons fall within the revised moments and maximum component weights called out in the T.N.
17 January 2002- 2 of the three ailerons are sanded to remove the gel-coat. The gel-coat on the ailerons and flaps is original, very hard and difficult to sand off. I'm using a 5" DA sander with 40 grit to knock it down, then finishing with 100 grit. I purchased the 10mm and 12mm brass rod from in Seattle - shipped quickly, exactly what I needed (as specified in the T.N.) and only cost $25. The long aileron weighs maybe a kilo at the most.
Tomorrow, after I spray a third coat of Simtec on the lower surface of the wing, I'll fiberglass the mass balance in place at the leading edge of the aileron using the templates provided in the T.N. My Nimbus is serial number 19, so it already has the mass balance on the inboard flaps and some mass balance on the mid-span aileron, I need to add a total of four pieces of brass rod, two to the inboard aileron and one to the mid-span aileron and two to the outboard aileron.
Needless to say, adding this much weight to the glider (mass balance weights, tips, gel-coat and filler) will require another re-weigh of the assembled ship and a revised weight and balance sheet. I'll bet I end up adding 20 lbs. to the empty weight compared to last years empty weight. There's a new SN-10B in the cockpit, I plan to replace one of the 7ah batteries with a 12ah and who knows what else will show up in the UPS truck that needs installing.
18 December  - in order to properly locate the brass rods on the end of the aileron leading edge, I must cut some templates out of Lexan using my scroll saw. The templates are provided by Schempp-Hirth in the T.N. full size. I cut the templates out, nested the cut-outs together to minimize offall and used 3M 77 adhesive to glue them to the Lexan. I drilled holes with the Unibit where the brass rod goes. Then I cut out the templates on the scroll saw (below)
Prior to laying the brass rod in the epoxy-saturated fiberglass cloth, I cleaned the rods using a phosphoric acid etch and sanded them with 100 grit to give the epoxy something to hold on to. I thickened the epoxy with my favorite strengthener - West System Colloidal Silica and gooped it all up real good, making sure the lay-up is fully wetted out.
Some wax paper between the rod and the templates to facilitate removal, vinegar to clean up the drips and the rods are positioned in place at the tip of the leading edge perfectly.
19 January 2003- I locate the one piece of brass rod required on the inboard aileron in its proper location using the templates I fabricated yesterday. You can see clearly how the template holds the rod right on the leading edge of the aileron bullnose.
This photo shows the inboard aileron with the fiberglass laid in along the interior of the bullnose and right up the forward face of the aileron spar. The rod is sanded, cleaned and laid into the wetted out cloth. I'll coat the rod liberally with epoxy and wrap the fiberglass around the rod. The ailerons are fabricated from carbon fiber and Kevlar and were very light prior to this exercise, I'll bet I've doubled their weight with the addition of all this brass.
The last step is to add a fillet of thickened epoxy to the joint under the leading edge bullnose - this will add strength to the joint; this additional strength is needed because the brass weight is essentially hanging off the end of the thin leading edge. See the photo of the T.N. below showing the location of the weight in relation to the aileron. The small blacked in area of the photo  is the fillet of thickened epoxy. Again, I used colloidal silica to thicken the epoxy due to its high strength in this type of matrix.
The last weights are epoxied in place and now I've formed the epoxy fillets and wrapped them in wax paper to form a smooth finish. Next step is to sand down the lower surfaces of the ailerons and spray on a coat of 2781.

1 February 2003, the inboard aileron is sanded to remove all of the old gel-coat. This is the biggest aileron so it took 2 hours to sand it all off. You can see the construction: carbon-fiber spar and end ribs mated to Kevlar and foam skins, very light and stiff until I add the weights, then it gets heavy and stiff.

2 February 2003, the second fill coat of Simtec goes on the left ailerons.
2 March 2003 and the lower side of the ailerons get sanded and are ready for spraying.
The lower surfaces of the left ailerons are sprayed.
21 February and I finished adding the additional mass balance weights to the right wing ailerons and installed the inner seal tape in preparation for re-installing the ailerons. Working from the outboard end, I install the aileron drive bolts and then slide them onto the hinge pins.
While trying to install a bolt on the aileron drive, I dropped a shiny stainless steel washer in the wing and the Tabby Cat believes that he can retrieve it. He's got one forearm all the way in and part of his head. He's determined!
With the ailerons installed, I lift the inner seal tape up and place it in the rebated area on the aileron, I'm using TESA fabric seal tape and it's very easy to work with, sticks very nicely to the aileron. Prior to applying the tape, I sanded the aileron and cleaned it thoroughly with MEK. I ran out of time, so decided not to re-finish the RH wing and that's why the lower surface looks imperfect and the old turbulator tape still exists.
February 22 - I laid a strip of Teflon tape on top of the aileron, over the fabric seal tape to provide a place for the Mylar seal to ride smoothly. TC is still trying to retrieve the stainless washer - he doesn't get paid unless he produces, so he pretty tenacious (he actually believes now it's HIS washer).
After the Teflon tape is applied to the aileron, I apply TESA transfer tape to the wing trailing edge, this will hold the Mylar in place. I'm using 22mm pre-curved Mylar from Tim Mara, there's about $250 worth of various tapes on the bench waiting to be installed on these two wing panels.
After laying on the transfer tape and working it down onto the wing surface with a steel socket to make sure it adheres properly, I install a strip of Mylar. I cut the Mylar at about 4 foot intervals in case it comes loose someday - I won't have the entire strip flapping, it will just shed one piece and fall off. You can see that I left a very small section (about .125") exposed forward of the Mylar to give the white covering tape something very sticky to adhere to. I sanded the underside of the Mylar with 280 grit sandpaper to give it some tooth with which to grip the transfer tape adhesive.
You can clearly see how the Mylar strip rides on the Teflon tape I applied to the aileron. I used the Teflon tape because I was afraid the Mylar would catch on the rebate in the aileron that the fabric seal lays in. The Teflon covers the fabric seal (and helps hold it down on the aileron) and provides a nice smooth, slippery surface for the Mylar to slide on.
A strip of TESA 4104 covers the leading edge of the Mylar seal to provide a very secure seal installation.
All done. The brown colored tape is the slippery Teflon covering the internal fabric seal. The Mylar rides on the teflon and the white TESA 4104 secures the leading edge of the Mylar/transfer tape joint. The aileron move very easily and with this modified sealing system, I do not believe I'll need to add seals to the top surface - this should be quite good enough.