||Martin Carolan replies to say he thinks the TP5/TP6 mod is sound in principle. He'd prefer to use wax release agent instead of grease, and make sure the BID tube was necked-in each side of the bushes to trap them. Nigel Graham replies saying the mod is in the public domain & he doesn't mind me applying for approval.
||Post letter to Francis Donaldson about TP5/TP6 mod. Remove masking tape from tailplane slot repair. Tape up tailplanes into jigs again, with end bits held on temporarily & protective foam strips covering those beautifully-shaped tips! Return them to storage area and get out the flaps (after some head-scratching deciding which bits actually are the flaps). There is nothing in the manual to say that foam parts 8 & 9 are the flaps; the only clues are that the flaps are airfoil section, and wider chord than the ailerons, which are more like the rudder in section. Cut peel-ply & BID, and layup the flap centre rib on polyethylene sheet. 7 strokes of the pump is just enough for the layup and the micro-slurry. There will be scrap offcuts of the sandwich that can be tested, so having only a few drops of resin left in the mixing cup as a sample is probably not a disaster.
||Take peel-ply off flap centre rib layup. Seem to be several areas of bubbles, particularly on the underside. This is likely to be between the brown foam and the glass (& thus not too significant), because the layup was squeeged onto the table, not onto the foam & so contact may have been intermittent. Will need to have a check with Martin Carolan about it. Trim edges with angle grinder, which is easier than the Dremel for straight lines, but seems to generate more dust. File and sand down edges.
||Phone Martin Carolan about flap centre rib and we conclude that there is no problem. Rod Ashforth brings multipole connector shells (as mentioned by Brian Oke in the RV talk) to Gloster Strut. Price is 2.60 each but I don't have change so give him 3.00 for one. Will need to check RS catalogue for inserts & see what else I need to order to save postal charges.
||Start to check setup for joining flaps. The jig blocks (both upper & lower) are slightly different heights at the joint, so will need shimming up when doing layups. Not a problem for joining, as the cocktail sticks will keep things in line sufficiently. Also note that the hot-wire has been bowing quite a bit at the trailing edge, so that the ramp up to the support block is curved; this is particularly noticeable when the cores are butted up for joining. Mark out and trim flap centre ribs. Start with hacksaw, and then switch to bandsaw, which is much easier but took time to change blade. File down to size and smooth off with Perma-Grit sheet. Check both root and outer sections for fit. Spend a lot of time looking for the cocktail sticks that I remembered seeing not long ago. They are not in the garage as I had thought, but in the kitchen cutlery drawer! Drill both ribs 2.2mm for cocktail sticks, and push into both halves of flaps. This is easiest done with flap sections held end-up so the rib lies in place. Lower end of flap section rests on piece of scrap foam for protection from dust or damage. Mask join of lower jig blocks for both port and starboard with polyethylene sheet. Free hardener valve, and mix up 5 strokes of resin with 3 doses of flox. Trowel onto starboard rib with mixing stick, leaving a holding area clean at TE, and push into cocktail sticks pre-inserted into outer flap section. Spread more flox onto TE and push home, trying not to get flox on the foam upper & lower surfaces. Squegee off at joint. Flap LE alignment appears good. Repeat on port. Plenty flox spare, so paint bottom of resin container float with it, still leaving enough for testing in the mixing cup. Order roll of 50mm peel-ply from Marineware. Send e-mail to Roger Bull at Europa (Andy is going to Oshkosh), asking for "letter of no technical objection" for TP5/TP6 mod.
||Lift flaps off jig blocks and find that quite a bit of flox has run down from the rib joints and spread onto the foam surfaces adjacent. Should have masked the foam, as when doing the tailplane slots. Make a plywood plate for the Dremel router base to ride on, with a hole in the middle wide enough to bridge the flox flow. No problem shaving it down pretty flush (with same bit as for carving rebates on edge of tailplane foam), although there are minor differences in level between the flap halves. Take it down slightly further each side of the rib to give a good start on cutting out the flox corner. Cut that out with the scalpel, and use the Perma-Grit sheet to get rid of all the blue foam on the rib face. Trim all support blocks LEs back by 75mm with bandsaw (another blade change!). Tack the starboard upper support jigs onto the table, and tack the flap onto that, with masking tape on the flap in hope to save lumps being pulled out of it. Check washout with digital level and find I can't use the factory procedure because I don't need as much as 8.4mm packing at the TE tip to get it parallel with the root. Use only LE packing instead and find I need around 6mm. Shim along LE of jig block to bring flap LE straight, and hot-glue the shims in place. Shave TE joggle lightly with long Perma-Grit tool to bring both parts into line. Draw lines at 30deg to LE for layup. Cut a piece of UNI 2.5m long, mark full length of two fibres about 340 mm in from edge, and roll it onto a cardboard tube. Can't decide if I should cut to size before or after applying resin to core. Probably best to do a dry trial run anyway to get starting position right. It would probably be ideal to cut all parts first and store them on separate card tubes, if I had enough. Check the trig and it looks as if the 8.4mm shim should be for the full chord of the jig, not with the LE trimmed by 75mm as it is now. Send e-mail to Roger Bull raising this question, and also mentioning the hot-wire drag at the TE support block transitions.
||Drive to Aylesbury and pick up a litre of Alodine & cleaner from Carl Pattinson. For a tenner he throws in some surplus fans as well.