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Thanks, geezeraviation. Abu, one of the reasons I am doing this (shiny) plane is that I am not quite ready for a model with weathering. I am reading the weathering thread with great interest though, for my next project.
A question for the qroup: what do I have to do with an EC3 plug on my new rx pack - if anything??? As the pix shows, there are two jacks on this battery pack. It seems to work when I use the little JR plug (into the rx) and ignore the big EC3 one. Am I missing something? Could I even cut off the big one??
< Message edited by allanflowers -- 3/25/2008 1:58:13 AM >
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I installed the switch on the interior box (an extension of the fuel tank enclosure). The box is a couple inches down from the top and not easy to see with the hatch on, especially once it get combing, pilot, etc. Then I spent a couple hours trying to run wires around. I had drilled access holes for the wires to go through but made them small. It is like building a ship in a bottle. Next time... much bigger holes! Now to figure out the rx mounting, pilot mounting, etc. Still no answer on my previous post and I also wrote Horizon about it. I suspect I will have to cut off that big ugly plug and solder a little (standard size) plug to it. What a pain.
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Can you place the Rx up by the serovs? That's the position I settled on. This way the weight is in front of the CG and there are no wires in the cockpit area (not that that matters much). I posted a photo of this setup in my Snipe thread a couple pages back.
Strange plug on the Spetrum Rx. It's really odd that it doesn't come with standard connections. Is this radio somehow supposed to be specialized for electric use?
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I have no idea why this EC3 plug is provided, although it may have application with electrics. This battery pack is listed as a RX pack which means, to me, that it should plug into a normal Spektrum receiver without any adapter. Unless I hear differently from someone who is an expert, I will just cut the plug off and solder a JR type jack onto it. I could then use either of the charge plugs to charge, the one from this pack or the one from my switch harness. With my instrument panel (not shown in that last pix), there isn't much room up on that surface for the RX - it would have to be crammed right up against the servos. That might be okay with a regular RX but the Spektrum has these two little short antennae and they say don't have them too close to metal. I will be using a lot of lithoplate up there, not to mention the cabane and LG wires already there. So I will place the RX on the floor below the seat, and have a false floor which will hide the wires. Fortunately the RX hardly weighs anything. After my Camel crash a couple of years ago, I will never put an RX inside the metal.
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Joined: 2/13/2004 From: Zentsuji, JAPAN Status: offline
quote:
ORIGINAL: allanflowers After my Camel crash a couple of years ago, I will never put an RX inside the metal.
I do hear you loud and clear on this and will certainly test my radio setup extensively. On my short range tests I've had no problems and an comforted by Frank Sopwith's comment that it is only ferrous metal that is a problem.
I forget to say earlier that your dummy looks outstanding! I'm really tempted to try a "full dummy" now that I have a whole book about the Bentley BRII including full technical drawings, but I've only got about a half inch of space.
< Message edited by abufletcher -- 3/26/2008 4:59:25 PM >
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Abu, you should be okay with a regular RX in that location because you will have the long antenna running out the back, not like the Spektrum RX with its tiny integrated antennae. I put in little liteply plates for my RX and aux RX, hooked everything up and it checks out. I managed to get all the wires through those dinky holes. The loose plug is for charging. I will probably tuck it in somewhere so it can be pulled out when needed. Upon putting in my instrument panel, I find a conflict with the switch. On the other hand, the panel needs to be updated to the photos I found on the RAAF Pup. Maybe I could hook or glue a little wire extension to the switch.
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I'm back. Maybe I should post a picture of the cabinet doors for the bathroom that I have been working on? Or the nice clean newly vacuumed garage? Nawwww, but here's a pix of some of the composite ribs (balsa & plywood) - as I finally get back to what's important. I am finally starting on the wings, the last basic component of this build.
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I'm still working on the ribs, preparatory to actual assembly of the wing. They are very fragile until they are glued in and I have to take great care. This is the price of thin, scale-like wing sections but it is worth it. Since the aileron setup will be somewhat different than that in the kit instruction, I have to do some modification before assembly. With a mini servo in each lower wing, wiring tubes need to be installed so most of the lower ribs will need a hole. I can design and build the servo mounting plate after the wings are assembled but the holes need to go in now. With the upper wing, I decided to try a workout something like the kit instructions suggest but handled in a little different way. There will be a cable (Kevlar in this case) connecting the two upper ailerons, just like the real Pup. I have installed two little Proctor pulleys to handle the cable direction change. In the center there will be an access hatch from the bottom to get at the attachment-adjustment mechanism which is laying in position on the drawing. Using Sullivan clevises and Dubro rigging connectors, adjustments will be possible to either aileron from this hatch. My little plywood bellcrank was made to accommodate three different angles between the "arms", 45, 60 and 90 degrees. I hope to use this to compensate for the differential which will be purposely factored into the system at the servo arms and where ever else it sneaks in inadvertently. I am starting with the 60 degree option. The cable will run cross-plane through red Sullivan Goldenrod tubes but will need smaller tubing as it exits the wing to the aileron horns. This may not work and could end up being a fussy system. On the other hand, I can always put in the standard fat non-scale push-pull link from the bottom ailerons later.
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In case you never got an explanation, that plug on your battery is for a new JR 2.4 receiver which has 2 separate battery inputs via fly-leads with the matching plugs. Only seen ads for it, but that's the plugs for sure. Just ignore it!
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I finally got going on the wings. There a lot of things to do to get ready for wing assembly and most of the day was doing those: cutting brass tubes and music wire, working on ribs, preparing the spars with their blind nuts, etc. I made a mistake on marking the spars for the blind nuts and plywood reinforcements by neglecting to take into account the fact that the spars do not butt up against the inside rib but penetrate into it. It is easy to assume there is a butt joint looking at the wing drawing but, when you look carefully, the spar doesn't show through by hidden line or anything on any of the ribs so the drawing is correct. This inside rib is about 4 mm thick (due to two layers) and the spar penetrates into it by 3 mm. So my wings are each going to be 3 mm less in span. No one will ever see it but I did have to modify the trailing edges, with their notches, to compensate. If anyone is referencing this build thread to do a Pup of their own, take note and don't make the same mistake (make your OWN mistakes, please). All the wing parts are extremely accurate and can be pushed into place then hit with thin ca. It is a VERY precise build and goes fairly fast, once one has all the parts ready. I started the actual wing assembly in the afternoon and have the two left sides pretty far along, as you can see in the photos.
< Message edited by allanflowers -- 4/6/2008 2:24:12 AM >
The Pup is looking great....For some reason AOL blocks the alerts sent by RCuniverse even though I subscribe to the thread....only occasionally does one get through....so there was some catching up to do. I think you are wise to keep the rx away from the litho plate. Ferrous or non-ferrous I'd do the same.
You may already be aware of this but Spektrum has a firmware update for their receivers that helps prevent the low voltage re-boot phenomenon. It's called "Quick Connect" and allows the rx to remember the last frequencies in use so it goes directly to them in case of a power interruption eliminating the need to scan for the tx to which it is bound. The update is free if yours does not already have it.
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Allan,
You may want to flip the brass grommets around on your servos. The "washer" side goes on the bottom. Not to nit-pick, I just don't want to see you airplane have a servo failure due to vibration.
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Thanks for the tips on Specktrum and the grommets. Both are things worth taking care of. I have been working on the panel and the wings. I found several Forstner bits that were perfect for the gauge holes so I drilled away. It has been stained but may need another application to match the other wood on the model. It should come out good once I do the back panel properly. For the test, I just used a pix of the full scale panel unskewed. The four wings are mostly done and I am ready for the center upper section tomorrow.
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RE: CD Scaledesigns Pup build - 
