EGB 953

So, over a month later, I finally got the chance to maiden the cub. Off to the flying field. Spent a good 20 minutes trying to get the engine running reliably. I noticed that it behaved much better with the battery still attached so wondered about the glow plug itself - not that much use but last run properly 27 years ago. I swapped glow plugs to one in my Irvine 46 and got a much better result. A bit of tweaking and we were ready to go. I got our club's top flyer to maiden her for me. he took her off, trimmed her out and handed her over, she flies well, nice and responsive but needs some rudder in the turn. Landed her ok, but those big wheels no match for thick and damp grass. Second flight I attempted to take off form grass. Nosed over twice - not enough elevator. Third time held full elevator and she got going but VERY hard to control direction, took off didn't release elevator, so stalled and nosed into ground, luckily very little damage (one aileron came out, dowels snapped otherwise ok). So next steps: 1. Replace dowel and glue aileron back in 2. Add more rudder deflection (it is less than spec and Club expert recommended it) 3. Mix some rudder in with aileron for turns 4. Buy new glow plug. On which point, any recommendations for which glow plug to buy? I have seen reference to hot and cold but have no idea. No idea on my Irvine one either, except it ran better> Any thoughts appreciated. Lastly next flight I will try hand throwing it and only move to grass when it is warmer/dryer. Image on the stand, prop looks odd because it was idling. Got some positive words from other flyers - not for my covering work mind you!

Just to sing the praises of 4-Max. gave them a call, extremely helpful especially as I must have sounded clueless to the poor chap, all sorted and amazing speed, at my door the next afternoon. I would highly recommend them.

Thanks!! That looks perfect!

Hi I would value some advice. while I wait for some decent weather to maiden my VMC cub, (https://www.modelflying.co.uk/forums/index.php?/topic/49070-vintage-model-company-cub-4-channel-trainer/page/2/#comments)), I got out my old eFlite Ascent 450 glider that met with the ground ten years ago after one of the prop blades snapped. The motor is duff and it seems is no longer manufactured. There is a similar engine but pretty expensive around £50 pounds. Any recommendation for an equivalent of the Eflite 450 890kv outrunner? I also note that the motors I see online all have the prop shaft sticking out the other end of the motor. How do I get one that Is positioned the correct way for a glider (motor insight the fuselage) or do I have to just hammer it through the motor till it sticks out the other side. Pics for reference and any advice gratefully received. I used to run it on 3s 1300 lipo which was plenty enough power for long flights and good climbs.

So. Had some time this weekend to finish the model. I set up the aileron Servos to the described deflection and programmed them in, I have set up lower rates at 80% of that for the ailerons and the elevator. then the wheels which were straightforward. I added a tiny drop of hot rocket to the lugs to stop them coming loose. Then added the stickers and the prop and spinner. dry weight comes in at 910g. So a bit heavier than I had hoped but hopefully still not too heavy. balancing on the main spar as advised by the instructions is perfect and with the fuel will be slightly nose heavy. so all that’s left to do is tune the engine and should be good for a first flight. I am sure it will be less stable than my Irvine Tutor trainer so must find a comparable aircraft on RealFlight so I can get some preparation in. oh I need to add my CAA operators number.

Well spotted. That has been my intention! But discovered I had tailplane upside down. The kit and instructions are really good but it would be really helpful to have a proper plan as I would have avoided that error I think. Mind you my covering skills leave a lot to be desired. ?

So. After a rather a long gap caused by Xmas holiday and busy start to the year I have been progressing the past weekends. I covered and then did a trial fit of the ailerons and discovered the covering had warped one. Despite the heat gun I could t get it right so removed the covering in one side and started again. Much better result. I glued in the hinges and then re glued them to make doubtless sure they were properly in place before adding horn for both. I also added the horns for the rudder and elevator and the. Glued those carefully to the fuselage. I used a plastic set quite and masking tape to ensure the tail fin was at the right angle. The tail palne was perfectly square - sign of how neatly the parts have been lasered. I waited for that for dry and then set to the pushrod links. My soldering iron episode not work, mind you been a while since I last used it, but a handy tip from someone at the flying club, used epoxy to glue the ends and then linked up. I then set up the throttle elevator and rudder to the prescribed throws. Fairly straightforward though the throttle did need quite a bit of EPA adjustment. so hopefully some time this week to set up the ailerons and add the wheels. Then balancing and adding stickers. I will need to tune the engine, want running smoothly when throttling up so I think I need to open the low rev valve a bit. With some luck I may be able to do that next weekend if it is dry.

Good advice thank you.

Good advice thanks! i will get to it this evening.

@Keith BerrimanAah thats not good, Thanks for the tip. Looks like an evening in the shed when i have finished work!

So after not much time last weekend, I was keen to get stuck in this weekend. Sadly, that was not to be, but I did get a few hours in. I covered the other side of the fuselage and then the underside and finally the top. My covering skills are not great - I struggle to be patient with the curves but am getting slightly better at it. I must say this Oracover is brilliant, easy to work with and looks good, even the bad bits. I have learned some important lessons I really should know by now - use as sharp a knife as you can and measure twice before cutting! Having finished the fuselage, I trimmed the covering off the tail parts, heading @Nick Crippsgood advice to be very careful not to damage the balsa. I trial fitted it and it all looks good. I Followed the guidance of @Jonathan M and ordered some M2 Clevis and solder extensions which arrived. I need to think about the right technique for soldering - fill the cavity with solder and shove in the piano wire or is there a better way .... hmmm. Anyway, then onto covering the wings. the video directs you to add the aileron servos before starting covering but that made no sense to me so i covered the bottom half of the wings in two pieces. I used a heat gun to tighten it and it looks ok, though there are some areas I will go over with an iron at the end and once I can test for an warping. I also saw some advice on a video about using a towel to support the wing as you cover it - great advice and my wife offered me an old towel that colour matched ... ? I then cut out the film and added the servos and threaded the wires but ran out of time before I could do the upper wing. I am not looking forward to the wing tips, big curves and I want it to look vaguely neat ... I may watch some videos on covering technique for tips. Thats it for the moment, will either have lots of time this week and next week as my holidays start, or none at all if we manage to get away. I had a moment where I started worrying I should juts have gone for the electric option, certainly the build would have been easier and I would have finished by now, but I am where I am and despite the bumps am enjoying it. So, onwards ...

Thanks! Great advice. I have ordered those. Not much building time this weekend, hoping to get some time on Sunday to finish covering the fuselage.

Thank you, that sounds sensible. What would you recommend for the control surface end?

Haven't had time to work on this but been thinking about a few steps down the line - setting up rudder and elevator linkages. I like z bends, simple, easy to do and strong, plus more attractive than bulky options. Should I z bend the piano wire at the servo end or the rudder/elevator end. if so, have to attach before i glue the horns in place, and, if any issues, harder to remove. Hmmm, got to think about that.

So, heeding the expert advice on this forum, I started off by adding additional mylar hinges to my elevators, a process I did not enjoy. I then made the decision to glue them in and cover in one piece. Before that i sanded the fuselage and ran another two coast of varnish over the front end to ensure it will be as fuel proof as possible. Then to covering, which was a bit tricky, especially as I have started with the tail plane and rudder which both feature lots of curves. I confess I don't have the patience for taking it very slowly, but despite that I enjoyed doing it and after several hours I had those both completed, not very neat I confess but it will do. I could then do one side of the fuselage before running out of time. That went a bit better and faster and looks better - mind you it is much easier. So pause again, hopefully i will get some time this week in the evenings or if not the end of next weekend. Plan is to finish the fuselage and do the wings, then final assembly.

@Jonathan M thank you for the advice on both counts. Hinges are glued so I can just pull them out. Regarding the stall behaviour - thats a good point, i will fly very high, thank you! Looking forward to my weekend - hinges, sanding, some varnishing (fuel proofing) and then covering - something I remember enjoying as a kid.

Oh no! OK, I trust your advice, so I guess i will have to add more ... not sure of how to space them, will have a think about that,

On the subject of gluing - the Hot Roket thin cyano has generally been brilliant and aside from gluing myself to the model a few times, getting a headache from the fumes and getting through an entire bottle (it runs very fast), I would use it again. I have used some standard balsa cement I got from SLECUK which has been much easier to apply but obviously slower drying, which requires clamping of some variety but is very strong when it applies. I was worried about overall weight - weighed the fuselage including the battery and receiver and it comes to 496g, wings should be about 110 and wheels are 80 so hopefully I can keep it below 800g and thus "only" 150g heavier than the electric version. I still calculate the wing loading to be quite low - overall wing area is 311 square inches so it should still fly - I hope! So next steps sand and cover - I have been watching some good videos on how to avoid wrinkles, what worries me most is warping the wing, but I guess I will only learn by doing. Photos when i have made some progress -nothing exciting cub yellow oracover but hopefully a positive adventure.

Having finished the fuselage I am ready to give it a good sanding and set to start covering - which may be a few days away as once again I have to work.

I then set about assembling the fuselage following the instructions. This is a very well thought through kit and it is quite easy to assemble and glue. I added additional support to the fuselage and to the holes for the dowel that will hold the wings. Having to the sides of the fuselage glued and checked it was properly aligned, I attached then engine to the mount (I drilled pilot holes first) and that was fine. However, it was at this point I realised that the engine is considerably forward (and of course much heavier) than the originally designed outrunner and this means the weight is very far forward. Fortunately, the receiver pack will be helpful in offloading that imbalance, especially if placed behind/underneath the elevator and rudder servos. I fitted these as well as the servo for the throttle and then planked the remaining components of the fuselage which generally came together quickly though I did do some clamping while the glue set.

Anyway, having got the right mount, I glued the additional ply firewall to the one in the kit and test assembled the ply box to accommodate it. I also set up the 2-ounce fuel tank and trial fitted it (just the right size, my 4 ounce tank wouldn't fit). Once I was happy I attached the correctly sized engine mount and found it slightly too wide so I had to shave the sides by 2mm on each side till it fitted. I fuel proofed the fire wall with epoxy and then attached the mount once that was dry. i then assembled the ply box and glued it in place before coating the front section in two coats of varnish to further improve the fuel proofing.

It has been a while since I updated the build log. I had a small hiatus when I discovered SLECUk had sent me the wrong sized engine mount. They were however, extremely helpful as soon as I reported it and sent me a replacement, superb service. This coincided with me having too much work so progress has been delayed. While waiting for the engine mount I did get on with the tail fine and elevator. Inserting the hinges was just as fiddly and irritating as it was when I was a teenager and my efforts were not terribly neat. Still a bit of sanding should leave them looking decent.

What a lovely story!

while waiting for the engine mount to arrive in the post, I headed off to the Shuttleworth collection at Old Warden. What a special place that is and surely one of the finest living museums in the world. They have some extraordinary aircraft there and in more normal times would surely be a huge visitor attraction. It was very quiet when I visited, which was at least safe from a Covid perspective but concerning for the museum.

Yes and thank you for the advice. I got the wrong engine mount so haven't been working on it, but my plan is to add an additional 3mm ply board to the firewall, and reinforce the formers with triangle stock as well as fuel proof the area with epoxy. The kit has the firewall attached to a ply frame which then links to the fuselage, so I am hoping that should do it. what do you think?