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My favourite 'hack' (a description which does it a dis-service). I think the updated wingtips are ugly - and the canopy has always been, so I did some mods...

Share of some flight video the Mrs filmed.

Just for info, the brackets of a switch description indicate the momentry positions ie (ON)-OFF-(ON) is a center-biased three position switch. ON-OFF-ON is a three position switch with no bias.

Been at something of a standstill lately whilst still waiting for retracts. A lot of weekends away and only building during the week has been slow. Anyway, I’ve decided I’ve gotta get on. I’ve told the retract manufacturer to not drill mounting holes and he’s given me the dimensions of the nose unit. I’ve made a template but it’s a very thin drilling area, I had two attempts and I’m happy where I’m at with bolts and t-nuts but always can be better. Localised reinforcement will be added at a later date. I’ve done some sheeting on the flank but I have to leave the fairing area until the wings are built. Added more stringers as well. I’ve installed the air tank as well which is a good fit. There’s a lot of thought that has to go into this model as it’s an enclosed fuselage and needs pull throughs for cables everywhere. A lot of work to get done this year but I’m enjoying the challenge. Hopefully next week when I’m back from Rome I can get a lot more done.

Update: Mike at HobbyRC advised that whilst the R88 is OK, it is not built to the same standards as FrSky receivers and is sensitive to antenna positioning. With that in mind, I returned to the field this evening to try again. I also went through the fine tune procedure again. Initial range checks very nearly sent me home as I couldn't get to 30 paces before RF was lost. However, on checking the antenna one of them was very close to the feed from the main batteries. I missed this because they are only in this position when the battery is fitted, I checked without... Once I moved one antenna, range check went up to >80 paces, and I got no RF warnings during flight. 3 flights without any issue at all. So it seems Mike is spot on; the antenna positioning is far more critical than it was, but once correct, all seems well. Graham

Some time later working through a fair bit of sandpaper The leading edges are all but done. I have a 40 odd year old Permagrit block that sticking some sandpaper to the curved grip makes for a really useful tool. The transition at the forward rake was a bit tricky but contrary to my concerns the aluminium cut back nicely. Just the tips to do and then a final sand all round and I can glass it.

One of the most satisfying of tasks I find is planing back and then sanding the leading edges. The tape is set 1/4” behind the face sheets as I had skinned over a prior 1/4” false leading edge. BTW the blue tape is Proper Job’s cheap version of the most excellent green Frog Tape. 1/5th of the cost and tbh I can’t tell the difference excepting the colour of course. At this point I have no idea how I am going to cope with sanding the profile around the aluminium inset gun barrel housings ?

Started the covering today. I'm rubbish at covering! Trying to keep it pretty bright and simple.

Part 3.

Down to individual manufacturers to deal with these days I'd imagine. I guess it's one reason most would like you to register online for guarantees, that way they get email details and can easily do a mailshot or two.

Tow and talk in my RC club last weekend https://www.youtube.com/watch?v=Oe6aphDBrPA Cheers Soren

I use a 1250kv 3536 on 4S. But, small prop - 8x6, and it shows ~400W. As kc's numbers show, 10x4 or 10x5 should work well on 3S.

I have a Turnigy 3536/6 which is used on a 10 x 5 APC Electric with a 3S2200 and draws 46 amps giving 462 watts. But the flight times are quite short with the 3S2200( around 3minutes). However the Swizzle Stick has some warning in the instructions about not using full power for long so the 10 x 5 might just give enough full throttle time on a 3S2200. As it draws 46 amps it would need a 60 amp ESC. With a 9 x 6 APC it draws 33 amps and much longer flight times but of course lower power at 350 watts And it would only need a 40amp ESC. A 10 x4.5 APC gives 402 watts at 37 amps and may be the best compromise. Just about OK with a 40 amp ESC. ( Keith - it's used like this on my 3.5 pound 'Rapido' model that I rarely fly, but I did fly it a few times some years back at Brocks Fm. It only gives about 4 minutes flight times with this model. Maybe I will bring it to Ospreys on Wednesday!)

My motor is a 3541 1270kv with a 10x5. With your 3536 1250kv with a 10x5 the performance should be the same because the kv and prop are the same. ? I am wondering what the Watts are at WOT and will be very interested in your Watt meter results. Steve

I think you’re being a bit harsh folks. The author is a very capable and knowledgeable electronics engineer and, whilst his opinion is just that - an opinion- it is one I would give much more weight to that many others that are often expressed with far less supporting argument.I think he’s trying to get across some valid points that we do need to be aware of. Having said that, I do agree that the article would have benefitted from a severe dose of editing. If it had been reduced to 50% of its current length I suspect that some of the more emotive remarks that have clearly wrankled with some would have got the chop.

A few more tasks ticked iff working towards skinning the wing underside. Paper servo wire tubes fitted and the servo mounts and hatches sorted. Also the canons/20mm guns needed some thought. I opted to make these from alloy tube with a M5 nylon bolt glued in the end. They fit through a larger short length of alloy tube which will be sanded back to the LE profile once the final front section of 1/4” balsa is fitted. An angled balsa block with a pronged t nut has been fitted to the inside of the inner spruce spar. When screwed in the guns are firm but have a little flex to mitigate against minor knocks. A further brass tube has been fitted inside the barrels to give the correct scale 20mm aperture of 4.4mm

1/5th scale T-21 from Mike Trew plan