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Last Modified November 3rd 2002.
1st October A snip and crimp evening putting connectors onto the radio panel.
2nd - 4th October Worked on the aircraft electronics.
5th October Prepared the cowlings for painting.
6th October Painter the cowlings and a few other little areas which needed touching up.
7th - 9th October No building.... but I have an excuse
10th - 11th October Carried on with the electronics.
12th October Sanded and polished the top cowling then started on the
bottom cowling. It was obvious within a couple of minutes that all was not well
with the adhesion. Then I remembered that I hadn't sanded back the primer before
I sprayed. I had done the top one when Nathan asked me to take him to the shops
and then had completely forgotton to sand back the bottom cowling. Without scuff
sanding Top Gloss will simply not adhere to the underlying surface and it peels
back in sheets as it now proceeded to do.
13th October No building, out with the family.
14th October One of the reasons I am building a fiberglass plane is because my metalworking skills are not the best. I proved that once again as I threw my fourth attempt at making my final section of the instrument panel across the room. My biggest problem is that the holes for the switching fuses I am using are circles with flattened sides and trying to hand cut twelve of these without error is proving to be a challenge. I did dig out the Aircraft Spruce catalogue to look at pre made panels but the price was just too much for me to even consider buying one. Luckily I still have lots of sheet aluminium left so it's back to marking out again.
15th October No building
16th October Cut and marked out the fuse panel. I coated the panel with engineers marking ink and then scribed the shapes I need to cut out onto it. For the fuses I marked out 13mm squares then scribed a 16mm radius arcs around the top and bottom ends.
17th October I cut out the first six fuse holes. I first drilled out 6mm holes in the centres of the marked squares then opened them up with a 10mm drill. The square was then filed back and test fitted for width against a fuse. The sides were relieved as required the end arcs filed back with a circular file. As the panel is thicker than the fuse retaining catches can accommodate I filed ramps into the top of the arcs on the back surface where the retaining catches are located.
18th October Cut out the remaining six fuse holes and the holes for the switches.
19th October Took a break from the main project and made a constant voltage battery charger to charge the sealed lead acid battery on the aircraft. SLA batteries require a constant voltage charge rather than the constant current supplied by regular car battery chargers if you want to maximise the life of the battery.
20th October Finished off the battery charger then spray painted the breaker panel.
21st October Carol was quite impressed. I powered up the battery charger - there were no loud bangs and the power to the room stayed on - unlike the last time I built a mains powered project. It works well and charges up a 17Ah SLA in about two hours.
I decided to make a small change to the breaker panel and added holes for
three LEDs. Two of these will for battery status while the third is a master
pump operating indicator. I am designing another PIC processor system that will
monitor the two main busses and will drive a multicolour red/yellow/green LED
depending on the voltage present on the bus. The main bus is also monitored by
the AV10 but I thought it would be nice to have an 'at a glance' status
indicator of the voltage. I added the primary pump checker as my primary pump is
turned on by the master switch and has no other visible indication of operation.
I have a few current sensors left lying around so I'll use one of those to
determine if current is being drawn by the pump.
22nd October Populated the breaker panel. I found that there was a small difference in profile between the two breaker types I was using so had to ease out half a dozen of the holes. The switches I am using for master and mags have polarising washers to assist with getting the switch the right way round in the panel.. As I have done in the past, I drilled small holes located where the tab on the polarising washers will go.
23rd October Did some coding for my voltage monitoring PIC.
24th October No building.
25th - 27th October No building, in Pauanui for the long weekend.
28th October Sat down at the kitchen bench and wired up the breaker panel. As there are three power busses plus a ground buss within the instrument panel all with spade connector terminations I have coded all wires terminating on one of the busses with coloured heatshrink. Main buss is red, secondary is yellow, avionics is green and the ground buss is black.
29th - 30th October Gee there are a lot of wires in this panel! With
the three individual sub panels in place, right now it looks like the inside as
been attacked by a bowl of spaghetti. All of these wires have to go somewhere
and for many of them that somewhere is a power buss or a ground buss. I spent a
couple of hours making these up myself and I am well pleased with the result.
The buss bar itself is a piece of 3/8" x 1/16" brass. At the ends pieces of 1/4"
square brass tube are sweat soldered into place and a further 1" long piece of
bar added to the lower side of the tube to allow the buss bar to sit off the
surface. The form the tags to which the faston connectors will fit I sweat
soldered faston tag bars that are supplied as part of distribution blocks to the
upper surface of the buss bar. The secret to this type of soldering is to ensure
that the brass is clean and is fluxed well. I use a locally produced liquid flux
for this called Duzall. All you do to attach a part is heat the pieces with a
pencil blowtorch and apply solder to the edge of one of the pieces. The solder
will wick in between the pieces and make a quick and strong joint. The tricky
bit comes when you want to mount two pieces close together!
