EarlyBird Posted November 26, 2020 Author Share Posted November 26, 2020 Second side being bent into shape and left to dry. Cheers Steve Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted November 26, 2020 Author Share Posted November 26, 2020 Dried and ready to cut out the battery hatch. Cheers Steve Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted November 27, 2020 Author Share Posted November 27, 2020 Hatch cut out and trimmed. I have not decided on how to hinge the hatch. I am thinking of using covering film the same as on the ailerons and elevator. Plate scribed to the shape of the hatch. and from the other side Next cut the plate to fit and then build the cowl on to it. Cheers Steve Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted November 29, 2020 Author Share Posted November 29, 2020 Ply plate cut roughly to size. Keyhole slots cut in the bottom. Screw holes drilled in the top. Fixed in place ready for the cowl to be built. Cheers Steve Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted December 4, 2020 Author Share Posted December 4, 2020 Just a note of caution to anyone considering following my design changes. Building the cowl is proving to be a challenge as I am now on my third attempt, which does not look promising. The first issue is that using the keyhole fixing I have to allow 6mm movement vertically down. The second is caused by the size of the battery box/engine mount leaves very little balsa on the sides. Third is caused by the motor being a larger diameter than the IC shaft . I could change the shape of the cowl and accept that it will not be scale, The nose ring would be a larger diameter. A 3D printer or a fibre glass cowl would provide a solution but both are beyond my skill level. Hmm what to do? Cheers Steve Quote Link to comment Share on other sites More sharing options...
Bob Bertram Posted December 4, 2020 Share Posted December 4, 2020 Steve, what about using very strong magnets and a couple of alignment pins instead of the keyhole arrangement? I'm sure Peter will be along soon to provide an answer. Quote Link to comment Share on other sites More sharing options...
Fun Flyer Posted December 4, 2020 Share Posted December 4, 2020 I used two magnets at the top and two dowels at the bottom for alignment and it hasn't fallen off yet. Not that its had much flying recently. Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 4, 2020 Share Posted December 4, 2020 THis is the joy of building. You can change things to suit your own ideas or what works for you, Especially when converting from ic to electric. Personally I don't like or trust magnets but that is a personal thing. I am a "nut and bilt or latch man myself. i.e mechanical connections. Quote Link to comment Share on other sites More sharing options...
Geoff S Posted December 4, 2020 Share Posted December 4, 2020 It looks as though you have access to the back of the firewall when the battery hatch is removed. What I've done a couple of times is to make the back of the cowl and drill through it and the firewall (before shaping it accurately) and then fitting dowels to locate it and with a through bolt (accessed from the battery box behind the firewall) into a captive nut in the cowl back to hold it. Then build a cowl on the part you've already made. In my case it was to fit a glassfibre cowl but there's no reason it wouldn't work witha built-up one. There's also the more drastic step of not bothering to make the cowl removeable. Once it's all connected up, provided you can access the esc/motor connections, there will hopefully be no need to get at the motor itself. Brushless motors are generally very reliable and don't need tweaking like a glow engine sometimes does, so you can seal it up with a degree of confidence. The only part of an electric drive train that's likely to fail is the esc and you can make that accessible. Geoff Quote Link to comment Share on other sites More sharing options...
Fun Flyer Posted December 4, 2020 Share Posted December 4, 2020 I would always use nuts & bolts or screws on an IC model but magnets seem to work on electrics. I use magnet to magnet, i.e. one in the firewall mating with one in the cowl secured with lots of epoxy. Its well known that anything that's designed not to be removable will need to be removed sooner rather than later! Quote Link to comment Share on other sites More sharing options...
Geoff S Posted December 4, 2020 Share Posted December 4, 2020 Posted by Fun Flyer on 04/12/2020 15:20:06: Its well known that anything that's designed not to be removable will need to be removed sooner rather than later! There's an element of truth in that So you could make the cowl removable simply by using locating dowls (cocktail sticks work well at about 2mm dia) but relying on the film covering to hold it in place. Easy to remove with a scalpel; not so easy to replace as it would need the covering to be replaced/reinforced but it's not going to be a frequent need. Geoff Quote Link to comment Share on other sites More sharing options...
Trevor Posted December 4, 2020 Share Posted December 4, 2020 I was about to make the same suggestion as Geoff. If you’re concerned about it getting untidy if/when the cowl has to be removed, you could cover the cowl separately then attach it with a strip of matching covering which can be removed and replaced if the need arises. Basically, it’s just a slightly upmarket way of taping the cowl in position! Trevor Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted December 4, 2020 Share Posted December 4, 2020 How about splitting horizontally, fix one half on easy enough, the other fits to that ? Quote Link to comment Share on other sites More sharing options...
Guest Posted December 4, 2020 Share Posted December 4, 2020 Back in the summer this was the first time using those strong rare earth magnet on a cowl. They are available from many on line purvayors. Make sure north/south oriented (they are so strong they sort emselves anyaway). 6mm dia 3mm thick - 6mm ply firewall and thinner lightply on balsa cowl prior to the balsa. Drill through light ply into 6mm firewall - don't go right through e.g. 3mm deep. Drop of epoxy in bottom hole electrical tape between facings to stop sticking. instant fixing which snap into place. As the prop/spinner is in from It cannot fall off in flight anyway. Here you can see marked positions Six places middle ones for 6mm alignment dowel(s) Ready for the magnets... Cheeks added Carving/Sanding Painted ready for rest of covering. This just pulls off (with quite a tug) once spinner and prop removed. It's now going to my standard method for cowl on sport jobby. Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted December 4, 2020 Author Share Posted December 4, 2020 Thankyou everybody. Your combined effort has convinced me not to give up. I have made a few adjustments and can now get the 6mm vertical movement needed for the keyhole fixing method, but I do like the magnet idea. I had not given up just stalled, which I am told is not a good idea in this hobby. I could have fixed the ESC and motor in permanently because, so far, they have always lasted longer than the aeroplane. Filled with new enthusiasm I have cut some balsa and glued it in place. Once again thanks. Cheers Steve Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 4, 2020 Share Posted December 4, 2020 Never give up! Just think about it and a solution will be found Quote Link to comment Share on other sites More sharing options...
Fun Flyer Posted December 4, 2020 Share Posted December 4, 2020 A perfect description NigelS. Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted December 5, 2020 Author Share Posted December 5, 2020 FF I agree. NigelS your pictures provided me with a solution thank you. Cheers Steve Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted December 6, 2020 Author Share Posted December 6, 2020 Progress on the cowl. Sides glued on and bottom pinned in place. Sides trimmed along the bottom. Glued and clamped. That was not difficult Cheers Steve Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted December 7, 2020 Author Share Posted December 7, 2020 I am gradually adding bits of balsa. Here I am test fitting to make sure that when in place that the cowl can be removed. Good job I did because this time if I had glued it the cowl would not have come off. Near miss I think Am I the only one who has to go this long winded process? Working on the top of the cowl next. Cheers Steve Quote Link to comment Share on other sites More sharing options...
Trevor Posted December 7, 2020 Share Posted December 7, 2020 No Steve, you are not the only one! I’ve just been through a similar exercise in 3D visualisation with the cowl on my Aeromaster - **LINK** Trevor Quote Link to comment Share on other sites More sharing options...
Trevor Posted December 7, 2020 Share Posted December 7, 2020 No Steve, you are not the only one! I’ve just been through a similar exercise in 3D visualisation with the cowl on my Aeromaster - **LINK** Trevor Quote Link to comment Share on other sites More sharing options...
Fun Flyer Posted December 7, 2020 Share Posted December 7, 2020 Yes EB, the only option I'm afraid is, pin, glue, cut, carve, check, repeat! You're getting there... Quote Link to comment Share on other sites More sharing options...
Fun Flyer Posted December 7, 2020 Share Posted December 7, 2020 Since we're on the subject of Fourniers, aren't these nicely done, Motor Gliders Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted December 7, 2020 Author Share Posted December 7, 2020 Thanks Guys Aeromaster looks good as do the Motor Gliders. The cowl. Apple cheeks to add then the fun part, Razor Plane time, followed by sanding. Cheers Steve Quote Link to comment Share on other sites More sharing options...
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