Europa #435 G-RODO Build Journal - 2020 04
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|1||Rapid Araldite delivered.||
Try again to get the screws started in the firewall holes of the aft baffle. Find that pressing on the head of each screw in turn while turning it with the shortened 1/8" hex key gets all 3 catching the thread. However, all are pretty stiff to turn immediately which makes me suspect that they might be cross-threaded. Pause for thought before winding them in too far.
Check the journal and find that on 2018-11-23 I actually decided to use AN3-5A bolts for fixing the aft baffle to the forward face of the firewall.
Remove the 3 button-head socket screws from the aft baffle. One bounces up and falls down but I can't see where it went - will need to find it.
Take baffle out of the way and try AN3-5A bolts in the holes to check if they are binding like the socket-head screws; they do seem quite stiff to turn from first entry. Then it hits me - if the anchor nuts were on the baffle flange instead of on the aft face of the firewall, it would be much easier to fit the bolts from the aft side of the firewall. Position the F14 Instrument Module to check access to the bolt heads and there is no problem; the bolts could be fitted and removed with the IM in place.
Drill out rivets on the 3 anchor nuts for the aft baffle-to-firewall fixing. Need to use 2.4mm bit on Tight Fit Drill Kit because of obstructions. Fill the rivet holes in the firewall with Hi-Temp RTV. Fit each anchor nut in turn to aft face of aft baffle flange with temporary screw and spacer nut. Drill rivet holes 2.5mm. Deburr forward face of flange. Countersink the aft face with 4.9mm drill bit at very low speed. Fit the anchor nuts on the forward face of the flange with the temporary screws, holding alignment with rivets inserted. Pull rivets and remove temporary crews.
Note that some of the aluminium mounting brackets on the lower edge of the F14 Instrument Module have become slightly loose - perhaps the aluminium rivets didn't have a strong enough grip. Drill out the rivets on one bracket with a 4mm long bit. Consider drilling out the holes and using 4.8mm stainless steel rivets that are handy, but find I have some 4mm x 8mm sealed-end stainless steel rivets in stock. Don't need the sealed end, but they will be fine as I don't have any SS plain ones in that size. Fit and pull them. Repeat drilling out and re-riveting process on all 4 brackets. Need to remove the fire extinguisher bracket temporarily for access to the last one at the port side.
Offer up aft baffle and thread wire 104 through it. Try AN3-5A bolt in centre firewall hole and that looks a bit short. Try AN3-6A and that looks almost too long, might be threadbound. Fit 3 off AN3-5A bolts with AN970-3 washers and the ends of all 3 bolts just appear through the anchor nuts. Probably better to have used the AN3-6A after all, but leave it for now. Fit 4 off 5/8" stainless steel button-head screws to fix aft baffle to footwells.
Fit the common earth plate on both sides of firewall. Leave the big half-nut and star washer for wire 105 loose for now.
Fit the isolator, starter relay, and ammeter shunt assembly to the firewall.
Now looking at the nearby forest of tabs that it would be best to change the firewall bolts sooner rather than later. Swap each AN3-5A for AN3-6A in turn.
Find wire 105 (strangely and sadly not labelled!) and fit it to the common earth point bolt with the star washer. Tighten the half-nut and apply inspectors lacquer.
Mount the busbar assembly on the port floor of the F14 Instrument Module (2.5mm hex key, 7mm AF stiffnuts). Mount fuseholders on starboard floor of IM (3mm hex key, 8mm AF, need to jam nut with small screwdriver as it enter the recess).
Mark and cut to length a piece of the larger oval conduit for the starboard side of the fuselage forward of the headrest. Mark it for bending to clear the bulge.
Update a few items on the GANTT chart.
Remove the hanger brackets from the ends of the temporary support shelf for the instrument panels. I want to be able to use the shelf even after the cockpit glazing is fitted, and those hangers would prevent that. Fit the F14 Instrument Module temporarily with just a couple of screws to locate it. Offer up the shelf and check the length of support needed between the port end of the shelf and the front corner of the thigh support - about 280mm. Find a suitable piece of wood and start marking it for trimming the ends.
Roll fuselage out onto drive.
Offer up support shelf for instrument panels to F14 Instrument Module with port side conduit held in place. Mark port side of cockpit for location of aft edge of shelf. Mark and with a dish cutter rout out a recess on the underside of the shelf for the top of the brake lever. Mark and saw off at an angle the top end of the wooden support strut. Offer up to the cockpit side and mark for a notch to fit the front of the seat. Cut the notch with the fretsaw, check fit and file to fit the seat shape better. Find a small brass hinge from stock and fit it to the top end of the strut and the port edge of the shelf with M3 screws and nuts in counterbores so they lie flush with the surfaces. Offer up the shelf again and the fit seems OK. For a bit more support, find a block of wood to fit on the tunnel aft of the brake lever, and fix it to the shelf with a long woodscrew. Try the fit again and it looks good and seems stable enough now.
Find a piece of wood from stock that is the right thickness for making bridges over the 27mm conduit clips. Mark it up and rout across freehand with the dish cutter in 4 places. Cut up to make 4 bridge pieces. Start to clean up the areas on the port side where there are still remains of the el-cheapo epoxy from the previous failed conduit bonding, but although it's quite soft in the sunshine and a chisel cuts through it reasonably well, it's hard to get it completely off to provide a clean bonding surface. So, abrade cockpit side in fresh areas slightly displaced from original sites. Shorten the tabs of 4 off 27mm conduit clips and abrade the undersides. Degrease clips and bonding areas with acetone. Mix a small batch of Araldite Rapid and spread it in turn on 3 clips and the 3 aft bonding areas. Fit each clip over conduit, applying a small piece of polyethylene sheet before the wooden bridge and then holding in place with speedclamps over the cockpit door sill. Mix a very small batch of Araldite Rapid and bond the forward clip in the same way, holding it in place with a wooden brace jammed against the side of the tunnel.
Find 3 small blocks of wood that are the right size for bonding bridges over the right-angle clips for the small conduit. Trace profile of a clip onto the face of one block and cut it out with the vibro-saw. That takes a long time and actually the cut is more of less 2 straight lines so do the others on the bandsaw. Slice them in half with the bandsaw to make 6 bridges. Chamfer the outer corner so that pressure can easily be applied at about 45 degrees.
Using the hot air gun, start to bend the conduit for the starboard side to clear the bulge. but it seems inclined to kink and flatten, even more than before. Re-warm and straighten. Find some rope (sisal not synthetic) that fits in the conduit and drag a double length of it through the conduit with a nylon trace. Now when heated the conduit keeps its shape much better, although the rope stranding does tend to grin through a bit. Complete the bends for the fuselage bulge and check the fit. Add a gently bend further forward to better follow the fuselage shape.
After pause for dinner, remove clamps from port conduit clips.
Consider starting on the port footwell conduit clips, but there is quite a bit of dust to vacuum out before I can start abrading. Instead consider doing the starboard conduit but quickly realise that the wooden bridges will need to be wider because the conduit goes close alongside the fuel return line. Tidy up tools and pull fuselage back into garage.
Move car out of the way and roll fuselage out onto drive for access. Check locations of the 7 clips for the port footwell conduit and abrade those areas. Abrade the tabs of the clips. Vacuum out the footwell. Degrease all the bonding areas and clips with acetone. Gather up various pieces of wood and metal and the lead weight collection. Mix a small batch of Araldite Rapid and apply to the 3 aftmost locations and the corresponding clips. Place clips and cover with small pieces of polyethylene sheet. Clamp the upper tabs of the first two clips to the edge of the thigh locker aperture with small G-cramps. Add various weights to hold down the bottom tabs of all 3 clips and press the upper tab of the 3rd one against the tunnel with an angled piece of wood topped with lead weights.
While that is curing, thread wires 111, 115, 120, 126, 128, 306, 307 and the 3 coloured ones from the manifold pressure sensor, through the firewall penetration sleeve. Leave wires 108 & 117 out for now, to leave room for the smaller more flexible wires which don't feed through as easily as the larger, stiffer ones.
After a pause for a snack, remove the weights etc from the clips and although there has been some movement from the ideal locations, they are all secure and acceptable. Mix another slightly larger batch of Araldite Rapid and in a similar fashion bond the remaining 4 clips on the port footwell conduit. Eventually manage, with a bit of a fiddle, to get pressure on all of them for the cure.
Check the manual for the location and drill 2 off 1/4" holes in the port fuselage for the pitot and static tubing. Remove the masking tape holding the roll of TU21RM tubing and clean off the gungy residue with petrol (acetone wouldn't shift it). Loop a nylon trace through the centre of the length of the TU21RM tubing. Feed the trace forwards through the port side conduit and draw the tubing after it. A bit stiff at the bend but comes through OK. Draw most of the length through, leaving some to go out through the fuselage side. Now start to wonder exactly what free length will be needed there. Open trailer and check the ends at the wing root. They are shorter than I thought, and won't reach over the spar. Probably should have been a bit longer so the connectors would be forward of the spar and thus clear of the aileron mechanism. Going back to the fuselage, if I pull out enough tube to reach aft of the spar, it doesn't leave a lot spare for the pressure instrument connexions. Check the other stock length of TU21RM and it is much longer, so pull out the first piece and draw in the new one instead. Now there is plenty of length at both ends.
Think about pulling the analogue fuel sender wires through the conduit and start to poke the nylon trace through again, but it won't go past the bend. Get a length of solid soft aluminium 8SWG wire and push it through, with a bit of effort, from the aft end. Tape the nylon trace to it and pull it through. Clearly I should pull all the remaining wires through the conduit together, and perhaps even leave a nylon trace in-situ just in case anything is forgotten. Leave the trace in place for now until all the relevant wires are ready.
The pitot and static tubing could be held against the cockpit side with pairs of 6.5mm clips, or I could make some new ones to bridge both tubes when I make the right-angle ones for the sight gauge. Can't find the connectors for the pitot and static lines; they were last noted in either box 5 or box 6. Box 6 has been emptied and although the contents of box 5 were transferred to an 18l Really Useful Box (RUB) on 2018-11-20 in the garage I can't find the connectors in there. Will have to leave the wing-root ends of the tubes dangling and blow the tubing out when I fit the connectors.
Remove the weights etc from the footwell conduit clips and they all appear to have bonded satisfactorily.
Roll fuselage back into garage.
|16||In preparation for drawing wires through firewall penetration, amend the wire database label layout to better separate the wire number from the rest of the info (which ends with another wire number when there are 2 on one terminal) by reversing it out white-on-black. Select all firewall-penetrating wires in the database and print the labels for them in this new format. Notice that the harness from the propeller slip-rings is not in the wiring database, as it is ready-made. Print out a copy of the main wiring diagram for reference.||
Get the propeller brush harness out of the 18l Really Useful Box (RUB). Check its length from the prop hub; there will be plenty to reach all the way to the CSC-1 controller, but the sheath will have to be cut short where the wires enter the firewall penetration.
Check all through the contents of that box for the PMC couplers for the pitot & static lines but no sign of them. I suspect they are hidden in the same place as the small Eliza Tinsley hose clamps and will turn up eventually. A general sort-out and tidy-up of parts, materials, and tools seems to be looming!
Temporarily fit the baffles with short screws to check the possible wire routings. Looks as though the optimum route for the CHT sensor wires will be up in between the cylinders to minimise danger of chafing on baffles; that also keeps them furthest from the exhaust pipes.
Print out the checklist of wire descriptions and terminations. From a stock of 22AWG Raychem 55 feed a length through the firewall penetration forward into the engine bay. Lead it over the engine to the oil pressure sensor as wire 337. Strip the end, slide a prepared length of heatshrink onto it & crimp on a red 3mm ring terminal. Try to fit it to the sensor and it won't go on! The terminal is 4mm, not 3mm - how did I make that mistake? Cut off the 3mm ring, re-strip wire and crimp a 4mm red ring. Fit to sensor. Dress wire under propshaft beside oil temperature sensor and across top of engine. Cut wire inside cockpit leaving plenty to reach the TP-1 instrument. Put a numbered tape flag on it (L7656).
Later it occurs to me that it would be good to install the prop controller brushes next so that the other wires can be laced to its harness sleeve for support - or maybe even run inside the sleeve?
Add wire 349 to wiring database for water hose temperature sensor. Change the cockpit-side terminations for the CHT sensor wires from butt splices to blades in the wiring database so that they can be swapped with the water temperature wire during testing. Re-print the firewall-penetrating wire checklist and labels.
Get out the propeller slip-ring brush harness. Cut off the whipping securing the sleeve at the aft end. Mount the brush assembly on the gearbox with the supplied screws and spring washers (6mm hex key). Dress the harness aft across the top of the engine. Thinking about how to secure the harness, notice an unused M10 tapping on the gearbox side. Find a stainless steel M10 hex-head setscrew that is near the length required, and a couple of internal-tooth star washers that will fit. Open the fixing hole in a MS21919-WDG6 cushion clamp to 10mm with a step drill. Shorten the setscrew to about 15mm with a hacksaw and tidy the end. Fit setscrew (17mm AF), washers and clip to the M10 tapped hole in the side of the gearbox. Pull wire 337 out through the firewall again. Thread prop brush harness & wire 337 through the clip on the gearbox and aft over engine again. Leave prop harness loose near firewall as those wires are quite stiff and will go through OK later. Take wire 337 back through the firewall and re-apply its flag.
With a razor blade, split the insulation of a red female blade connector on the open side so it will fit onto the oil temperature sensor. Draw a length of 22AWG from the cockpit through the firewall for wire 336, following route of wire 337. Strip the forward end, fit a prepared length of heatshrink and crimp on the prepared blade connector. Slide the label under the sleeve and shrink it.
Lace wires 336 & 337 to each other and, further up, to the prop brush harness.
Split the insulation on another red female blade for the water temperature sensor and then realise I have not made provision for the earth side of that sensor - it's insulated from the engine block by rubber hoses! It needs a 10mm ring terminal but I only have a yellow (12-10AWG) ring of that size in stock. Find a rather rough-looking uninsulated 10mm ring crimp terminal that might do, but would prefer something better. Order some proper 10mm ring red crimp terminals from Farnell . Add the water temperature sensor earth wire (350) to the wiring database.
Leaving aside for now the wires to the water temperature sensor, feel a length of 22AWG from the cockpit side through the firewall and across the engine for wire 318 (#2 CHT, port forward). Thread it down between the cylinders as planned. Terminate and label it as usual, and add a length of the
398-903 sleeving, also labelled, where it passes between the cylinder heads.
Now looking at its proximity to the spark plug leads for some distance, I'm not happy with that routing. Search a bit online for advice about routing sensor wires along with ignition wires. Can't find any definitive advice, but there are suggestions to avoid running any other wires closely parallel to ignition wires unless they are screened. Don't particularly want to switch to a screened wire so try out other routings. Leading the wire forward would allow it to be laced in with the oil sensor wires, but would put it very close to the exhaust port and exhaust pipe, which I want to avoid. The only other option is between the inlet port and the spark plug, although there is a danger of abrasion against the edge of the baffle. I could fit a grommet, but unless excessively large, that would trap the wire and the baffle together - awkward for future maintenance.
Eventually decide to make a small slot in the baffle and line it with Firewall Fabric as for the various hoses that cross baffle edges. Mark the baffle edge for the location of the slot and remove the baffle. Find a small offcut of Firewall Fabric large enough to cover the proposed slot and mark it out with washer locations and hole centres for punching. Punch it on the marked spots, 4mm for rivets and larger for the wire. Position carefully on baffle and mark through holes with felt-tip pen. Centre-pop and drill holes. Cut a slot from the edge of the baffle to the wire hole with the small nibbler. Cut a slit in the Firewall Fabric. Deburr holes and smooth cut edges of baffle. Rivet Firewall Fabric in place.
10mm red ring terminals delivered from
Re-fit port forward baffle. Ease sleeved wire 318 into the protected slot. That all looks satisfactory now.
Tape a scrap of Firewall Fabric to the front of the propeller brush housing to keep the brushes retracted and safe from accidental damage.
Make up and label 22AWG wire 350 with the 10mm ring termination and re-fit water temperature sensor. Terminate aft end of wire 350 and connect to firewall earth point.
Feed 22AWG through from cockpit for wire 349. Terminate forward end and label. Cut off at cockpit end and apply tape flag.
Feed 22AWG through from cockpit for wire 317. Cut a suitable length of sleeving for it and pass sleeve and wire between spark plug and inlet pipe of cylinder 3 (starboard aft). Terminate and label wire and sleeve. Dress across top of engine to join bundle of other wires. Mark starboard forward baffle for position of slot for wire 317, and remove baffle. Find an offcut of Firewall Fabric that will do to line the slot in the baffle. Mark hole positions on it using washers. Punch at 5 locations for rivets and wire. Mark through the punched holes onto the baffle with felt-tip pen. Centre-pop and drill 5 holes 4mm and deburr.
Find the pitot-static connectors and the Eliza Tinsley small hose clips in box 26 which was hidden behind the instrument panels in the office. Need to update the storage database to correct this poor record-keeping.
Search online for cable bushes. Find some that look promising at Rapid Electronics , so order them and some screwed plugs that might be suitable for closing the hole on the side of the throttle box.
|22||Amend parts database entries for the pitot-static connectors PMC 17-02 & PMC 22-02 to show correct location of box 26 for those not yet used, and add a (latest possible) used date for those already fitted at the wing root.||
|24||Open the centre hole in the baffle to 10mm and deburr. Cut a slot from the edge to the hole with the small nibbler and clean up edges.||3253.0|
Mark and cut a slit in the Firewall Fabric piece for the wire. Rivet it to the starboard forward baffle. Re-fit the baffle. Find that temporarily removing the connexions to the oil tank makes it easier to operate a small ratchet driver on the inboard screw. Slide sleeved wire 317 into the protected slot in the baffle. Check that it is correctly dressed across the engine to the loom and cut off to a suitable length inside the cockpit. Apply a tape flag.
Go through the wire checklist, ticking off each free wire end on the cockpit side of the firewall penetration. Besides the heavy gauge wires 108 & 117, the tacho cable and the fuel pressure cable, the only 22AWG wire outstanding is for the alternator fail. Draw a length of 22AWG through the firewall for wire 119. Slide on a prepared length of heatshrink. Crimp on a red female blade connector, slide the label under the sleeve and shrink it. Then find that the insulation on the connector is too bulky to go into the blade connector block. Cut off the connector and crimp on another with slightly smaller insulation. That goes onto the connector block with a bit of persuasion.
Bring the tachometer cable up past the baffle - will need to fit a Firewall Fabric patch to protect it, in the notch originally intended for the C04 water hose. To feed the cable through the firewall penetration, feed a length of sleeving through from the aft side and having inserted the cable terminations into it, draw the whole assembly through. The cable will need to be extended to reach the instruments.
The fuel pressure sensor cable is shown with blade connectors joining it to the extension, but I now think butt splices would be better. Also the flying lead reaches very close to the firewall penetration, so maybe should be shortened to keep the joint away from that. On second thought, it could just be looped. Check what size 4 off butt splices in parallel looks like; seems OK, so there is no need to stagger the joints and have much longer lengths of the cores unscreened. Select a piece of heatshrink large enough to cover the butt splices and slide it onto the flying lead. Draw a length of 3-core screened cable through the firewall and strip the end. Join each core in turn with a butt splice, and then the screen. Slide the heatshrink sleeve to cover the splices and shrink it. Loop the flying lead on top of the aft baffle and put a temporary cable tie on it.
Now that all the smaller wires are through, push wires 108 & 117 through the firewall penetration. Renew their tape flags.
A means will need to be found for securing the GR6 terminal block; the holes are 3mm. Nutplate bonded inside footwell? Wires 122 & 123 need to be fitted between GR6 & capacitor as well as the pair from the alternator to GR6.
The magneto cables are the only firewall-penetrating ones outstanding, and I notice they have not been included on the wiring database. They will need to be drawn through the firewall before the Instrument Module (F14) is fitted. Other things that will need to be done before F14 fitting include mounting of fan, GPS antenna & audio-out sockets.
|27||Add magneto wiring to wire database, allocating it to area 900.||
Cable bushes and hole plugs delivered from
. The bushes, on examination, don't look very promising, but the hole plugs seem fine. The core diameter of the M16 thread is about the 14mm of the existing hole in the throttle box, so the hole will not need much opening up to accept the plug.
Make up and label wire 122. Fit it onto the GR6 terminal block.
Make up and label wire 123. Fit it onto the GR6 terminal block.
Cut the sheath on the wires to the propeller brushes at the entrance to the firewall penetration and (with a bit of effort) push the wires through to the cockpit side.
Cut off the uninsulated blade connectors on the alternator leads. Replace with yellow female blade crimps.
The ends of the fuel hoses to the carburettors are getting in the way a bit now, so connect both of them to the 4-way cross.
Remove the port aft baffle. Mark and cut out a piece of Firewall Fabric to cover the notch in the baffle that was originally for C04 and is now where the tachometer cable will come up through. Punch and drill holes and rivet the Firewall Fabric patch in place on baffle. Doesn't quite fit when offered up - must have failed to measure properly - need to remove 1 rivet and trim edge of FF to clear edge of footwell. Now fits OK. Fasten baffle with 0.5" stainless steel button-head screws. Thread tachometer cable through slot in FF. Dress alternator cable and fasten it to baffle with a couple of MS21919-WDG6 cushion clamps. Fit alternator connectors to GR6 terminal block.
Find a piece of aluminium extrusion 4.5mm thick. Cut off a piece about 1mm x 52mm to act as a nutplate for retaining the GR6 terminal block. Mark, centre pop and drill 2.4mm on centreline, 36mm apart. Tap M3. Check fit on terminal block, which is fine. Mark through the terminal block onto the top of the footwell and drill through 3mm. Fit M3 x 20mm socket-head screws and washers to terminal block and check that they line up and drop into the holes in the footwell. With fuselage in garage, can't reach to fit nutplate inside cockpit. Will epoxy it in place, and use Loctite on the screws.
The firewall penetration for the magneto leads looks quite small. Check that 2 lengths of 22AWG screened will go into it - firm fit but OK. Check the Rotax box for the magneto crimp connectors, and discover there are also connectors there to mate with the ones on the tachometer wires - I had forgotten about them.
I intended to print the labels for the magneto cables but discovered that the wiring database did not yet have a layout for that. So, duplicate the wire labels layout and re-purpose it for cables, then print out the magneto cable labels.
Pass one screened cable through the dedicated magneto firewall penetration from the cockpit side. Strip the end and shorten the screen for a solder sleeve. Strip an end of 22AWG wire and line it up with the cable screen under a 1/8" solder sleeve. Shrink and melt the solder sleeve using the highest setting on the heat gun. Then realise I have forgotten to slip on the heatshrink sleeve for the cable label. Dress the cable and cut off at a generous length inside the cockpit. Pull the free end through and fit the heatshrink from that end, then insert and shrink on the label.
Referring to the Rotax illustration, slide the grommet onto the cable inner and then the connector. Crimp with the Ideal pliers fitted with the 30-586 jaws, after dressing the tabs slightly inwards. The wire crimp goes in the 22-18 section and the grommet and insulation crimp in the 16-14 section.
Cut the earth wire to length, slide on heatshrink and label it at the solder sleeve end. Slide on a 2nd piece of heatshrink. Dress and check length to common earth point. Fit red female blade, then insert label and shrink. Fit blade to common earth point. Feed the free end of the cable back through the firewall and put a tape flag on it.
Feed the screened cable from the reel forward through the firewall penetration. Quite a tight fit and needs a good pull to get it through.
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