||Dig out the offcut of polyester resin layout for blanking off the unwanted hole beside the fan. Rub down the upper face with a Perma-Grit block and degrease with acetone. Secure to a lath of wood with long thin nails tapped in at an angle to stop it blowing away. Spray a light coat of Halfords matt black acrylic. After about half an hour do another coat.
||Spray another coat of matt black on the fan hole blanking plate. Weigh the F14 instrument module - 2405g. Make a paper template of the shelf lid shape. Transfer the paper outline to a piece of 1mm 6061 aluminium sheet. Cut out roughly with aluminium-cutting blade in jigsaw. Trim with tinsnips and files, deburr edges. Try it for size; needs some further trimming. Take more off sides with millennicut file and corners with tinsnips. Smooth off and deburr. Fit now looks OK. Noting that the piece of layup cut out from the middle of the shelf has curled up quite a bit since it was sprayed, decide we could dispense with it, and with the flange that was to support it. Start to cut off the flange, but the oscillating saw battery needs charging. Not sure what size fixings to use - 10-32 might look a bit large, but the next size of button-heads I have in stock is 6-32 and I don't have any 6-32 anchor nuts. Offer up the instrument module to the firewall to see how much might be needed to come off the bottom flange to fit the tunnel, but note that the instrument module is somewhat wider than the firewall and the edges are scraping on the fuselage sides. Stop for thought and post a query about it on the Matronics e-mail list.
||Several replies to my query on the Matronics e-mail list indicate that the flange on the instrument module is commonly found to be too big and the usual solution is to lay up a flange on the inside to replace or supplement it.
||LAS Aerospace order with 1/8" NPT fittings & AN840-6D arrives.
||Move trolley to utility room and set up 2 fan heaters. In the garage, notice that the clip securing the bottom of the conduit down from the fin has come unstuck. Find an offcut of worktop about 600mm x 1100mm to do layup on and put it on the trolley. With sandpaper on oscillating saw and power file, abrade all the bonding areas on the upper flange and about 50mm deep on the top inside edge of the F14 instrument module. Mask off the holes for the fan and GPS antenna with masking tape on the outer face, to reduce chance of drips and runs on the already-painted surface. Lay a sheet of polyethylene on the worktop and put F14 on it. Trace the outline inside & out. Add another line about 50mm in from the inner side. Mark and cut 2 off each of 900mm x 300mm and 300mm x 150mm BID and lay in place on polyethylene sheet. Mix a peg-4 (75g) batch of epoxy and wet out most of the larger area of BID, along the marked lines. Mix a peg-3 (60g) batch of epoxy and wet out remainder of BID. Add a small 2-layer patch of BID offcuts to fill the space between the 2 main sections of BID. Paint the flange of F14 with epoxy and position it on layup. Clamp down with pieces of wood on flange, with polyethylene sheet interposed to stop the wood sticking. 30C, 30% RH. Leave to cure for a while. When the layup is firm but still tacky, mark & cut 3 off each of 1000mm x 100mm and 150mm x 100mm BID. Mix peg-3 (60g) epoxy and add 3 doses of flox. Butter it into the corner between the earlier layup and the inner face of F14 (too much, about half would have done). Lay BID in place, 1 layer at a time. Quite tricky getting the small pieces into the narrow space at the starboard side. Just enough tack on the previous layup to keep the BID in place. Mix peg-4 (75g) epoxy and wet out the BID, taking care not to get epoxy on the painted outer surfaces of F14. Not quite enough, so mix a peg-1 (30g) batch to finish wetting out. Cut and apply peel-ply in small sections. Still 30C, 30% RH. Leave to cure overnight with fan heaters running.
||Layup well cured; turn off fan heaters. Remove peel-ply. Trim off excess unwetted BID with Tuff-Kut scissors. Trim outside of layup back to edge of original flange with diamond wheel on angle-grinder. Mark a line 15mm beyond the flox corner on the inside and trim to that line with TC blade in jigsaw. Trim edge of fan hole with diamond blade in Minitool jigsaw. Open GPS antenna cable hole and smooth off cut edges with Perma-Grit files. Smooth off transitions between wetted and unwetted areas of BID with power file.
||Take top of fuselage out of garage onto drive, for easier access to firewall. Remove the conduit clip that had popped off and abrade its base and the bonding area well. Mix a small batch of 90-second epoxy and attach the clip with it, clamping in place with a wooden bridge and a small piece of polyethylene as a release film. Offer F14 up to the firewall to see where it needs trimming and with the padsaw cut off most of the side flanges for about 40mm up from the base. Offer up again and check where trimming is needed in the central bottom area. Cut that back with the padsaw in stages. Need to take it back until clear of the washers on the LG01 fixing bolts, and sideways to clear the layups around the tunnel-firewall junction. Trim and check repeatedly until it seems satisfactory, using the power file to chamfer the edges for better fit. Use spring clamps to hold F14 in place against the firewall and mark a line on the forward face of the flange against the top edge of the firewall. Trim back to that line with padsaw. Place the fuse hatch access cover in position and check where the fixing hole should be. Mark them midway along each edge and 10mm in from the edge. Centre-pop and drill the cover 3/16", then lay it in position and hold while drilling through one hole. Insert 10-32 screw to keep it in position and repeat for the other 3 holes. Fit anchor nuts on top of the flange with temporary short screws in the usual way. Drill through the rivet holes 2.5mm, remove the anchor nuts and countersink the holes. Fit the anchor nuts in their proper place under the flange with temporary short screws and set the rivets. Clean the resin weeps from the internal flange layup off the F14 instrument module with a razor blade and rub down the those areas with 600-grit emery. Rub down the fuse access cover with 500-grit Abralon. Take it out to the carport and degrease it with acetone. Spray it with etch-primer. Take F14 out to the carport and wipe down with tack rag. Not entirely satisfied with the result, so give it a wipe down with meths on a tissue followed by a dry-off with a clean tissue. Give cover plate another coat of etch-primer. Spray F14 with Halfords matt black, concentrating on the reworked areas. Give the cover a coat of matt black, then F14 a second coat and finally the cover a second coat of matt black. Take clamp off conduit clip. Lift fuselage top back into garage. Move F14 and cover plate into garage.
||Mark the centre of the F14 instrument module top flange then mark the approximate positions of the securing screws, 4 each side and 6" apart, on the forward face of the flange. Trim off, with Dremel cut-of wheel, unused sides of the M4 anchor nuts where rivets could not be fitted. Cut a few mm off the end of the remaining piece of 3/4" aluminium hex bar to bring it to about 31mm. Machine it using the same procedure as before, but leaving 15mm of hex untouched instead of 13mm as originally, to give more meat for the NPT tapping. Start to drill the 7/16" hole for the NPT tapping before remembering that I needed to do a trial fit to check which face it should be on. Complete the drilling & tapping then clean it up and do a trial fit with a 9mm O-ring in place. The NPT tapping finishes pointing straight down, so at least it does not foul the other port, but as it is pointing towards the ports on the DI it would be slightly better a sixth of a turn in either direction. As the thread is 7/16" x 20TPI (12.7mm thread pitch), 60 degrees clockwise adjustment can be achieved by skimming about 0.2mm off the face that the O-ring seats against. Put it back in the lathe and do that. Also take about 1.5mm off the nose of the thread to make sure it does not bottom against the filter screen. Clean up and re-fit and this time it looks OK.