Nigel R

A 48" 3d model clocking in at 1.3kg should land about as hot as your average ice cream, I think borderline whether you'd benefit much from convert to wire gear, just epoxy what you got back in place. Add some 1/32" ply doublers inside the fuse sides (make sure they extend fore/aft of the gear by a couple of inches) and then reinforce the gear plate / doubler joint a bit with some hard balsa or liteply. Should be plenty.

What's the airframe? Size? Weight? The mount plate looks a bit fragile. If I'm honest I'd replace it for a torque rod type gear. is the best practice for smooth landings you can do. Spend a few flights doing nothing but. Additional challenge, keep the airframe rolling on the main legs only, without the nose gear or tailwheel touching the ground.

With respect Robert, (next to) none of that is true. Plus. The current F18 is totally different airframe to the original F18. F16 is a previous gen, export market product. As is F15. Any mention of air combat superiority of Rafale or Eurofighter over F35 entirely misses the point of what F35 does; if an F35 is dogfighting then things have already gone very very wrong. Nobody is making any new F22, not a chance, nada, its now old tech anyway. Yours, industry insider (of sorts). All I state above is verifiable online.

It'll be a story if it doesn't return to the PoW but otherwise... slow news day...?

I'd strongly consider Simon's suggestion. It simplifies things a lot. I don't know what the appropriate size servo will be for this build but at this kind of scale the links start being a larger percentage of the whole control loop. That said, I've used snakes for my current build which has twin fin/rudder arrangement. But... It is bigger (7 or 8lbs expected) and I have 40g standard servos on each fin. The snakes operate each rudder directly (well, there is a horn that goes forward of the hinge line - that will allow me to hide the whole linkage in the tailplane). I like the Comet shape the best! Very racey.

looks great! watching with interest

I'd make ribs for this sort of wing from the foamboard that hobbycraft sell - it costs buttons by comparison to balsa ribs. That said your existing material choices look perfectly sound. Space the ribs around 3" or maybe a touch less. What works to get 11 or 12 ribs on a wing this kind of size (with 10 or 11 "gaps"). Are you using bands to hold the wing on, or dowels and bolts? If it is bands - add an extra rib in between the two root end ribs. It'll help keep the sheeting in one piece.

Trickle charge can be bad if they're left in 24/7, but that's not the kind of case we're talking about here. I maintain that NiMh are very easy to manage. 1800mA on the charge part of this cycle at 1C is a pack in excellent condition. And, note, that result from a 10 year old pack. Speaks volumes for quality. On a similar note. I inherited a small pile of eneloop flight packs of somewhat indeterminate age (most likely all around 2010 - 2015 purchase date). All 2000mA AA cells. To see what I had, I cycled them twice, 1C discharge, 1C charge. Not a single pack was below 1700mA on the charge cycle. The Vapex low discharge cells I bought did not age nearly as well - several failed cells, a fair amount of lost capacity. If I remember I'll post the results. Pretty impressive given they'd just been chucked in a box for 10 years and not touched. I forget which electrode suffers most in NiMh but (IIRC) tiny crystals form on the electrode and block it from contacting the electrolyte. Some of these are broken down by a decent cycle. Formation is faster at full discharge and slower at higher charge levels. I think. I'm a bit hazy on the details here (sorry). Regularly used packs won't suffer too much though. As ever YMMV.

The recommendation from BU is a bit slower - 0.05C - to avoid issues. For 2Ah Eneloop AA that is 100mA. https://batteryuniversity.com/article/bu-408-charging-nickel-metal-hydride

Mine uses 4mV as default, I believe. The lower the better for NiMh (the ideal point is where the voltage curve is flat, but detecting that point is beyond most hobby chargers). Too low and you would get false peak detection problems. I would stress 7mV isn't "too high" to cause any concern though. Main benefit of slow charging nimh packs is that it will balance the cells.

With NiMh, the lower peak the better (within the limits of your charger, some aren't accurate enough). They show a flatter peak than NiCd do. IIRC 7mV is getting toward a NiCd setting. Not exactly a deal breaker though.

Normally I slow charge nimhs too. If I'm cycling them, the AA size Eneloops get discharged and then charged at a rate of 2A. Discharge limit set to 1V per cell. I've not changed the delta peak detect from 4mV.

That's the rub Bruce, the torque rod setup is somewhat more straightforward to key into the main wing structure (especially in a foam wing). The underside block is mainly pushed upward into the wing, and backward; both of which it can easily resist in an average wing structure. The top block - holding the torque arm - is pushed forward; again, easily restrained by your average surrounding wing structure. With retracts, if you can attach the mount plate securely to a couple of ply false ribs, then you have a similar structure in place - this will also distribute load to the upper and lower sides of the wing structure. Coil springs on piano wire retract legs help absorb the loads. If I'm making my own legs I wind several coils on, rather than using a straight leg or a single coil. All grist for the mill. Sprung oleos are clear winners in terms of properly absorbing the bumps and bounces. All of which takes a bit of stress and strain away from the mounting points. Unless your landings are the butteriest (?) of butter smooth and you fly from the perfect tarmac strip, the legs themselves will often need a tweak. C'est la vie.

In my (slightly) limited experience of retracts: Solid install of any mount plate or bearers is key to long life. Get them keyed into the wing structure and spread the load, just like any regular U/C. That's it really. "With a long enough lever" etc. Get the retract on a nice solid mount and make sure it's firmly attached. Easier on a built up wing - foam wings (in my opinion) need extra structure embedded to achieve a decent mount for the retract unit. I would note, the average retract unit has about an inch gap between fore and aft fixing points. This is not so dissimilar to the length of "arm" on a torque rod setup. Nearly every fixed gear sport model I've built has that kind of U/C. To my mind this means the retract unit is putting a similar strain onto the wing structure as a fixed U/C would - so it's not impossible to handle. Fuselage mounted aluminium or carbon gears are similar - often quite narrow where they attach. These also need solid structure to bolt to. YMMV.

After two weeks Eneloops will have lost very little charge. What's the reasoning behind cycling them at least twice? They would only need the quickest of top ups... if that.

To the best of my knowledge, they don't have higher internal resistance than standard NiMh cells. Eneloop performance under high load is very good - as good or better than any other NiMh, I would think. Vapex are pretty good for the money, but - personal experience only - I have had several cells fail. I use these for household use, torches, remotes, bike lights etc. Not sure I'd use them for an airframe any more. YMMV of course.

retract servos run 180 deg for good reason, this puts zero load on the servo when locked either up or down; it also means the servo produces a lot more force at the extreme of travel, which all aids getting the lock in place; a normal servo does not. To put it another way, the geometry works for the retract servo and works against a normal servo. Of course you can modify some normal servos to travel 180 degrees, but far simpler and better to buy one designed for the job. Whilst a well adjusted mechanical retract is very reliable, it is well worth checking the operation before every flight. Legs can bend and foul the wheel wells. Find out before committing aviation.

Smart looking model. Fabulous noise maker up front. Great flying site. Nice one Ron. 👍

Life does have a habit of getting in the way of the important stuff! What's the plan for power, are you going electric or IC?

Mylar hinges shouldn't be stiff. Perhaps something is amiss there? Did you glue the snake in place? The outer needs to be secure before use. Anyway. Carbon rods are also perfectly good method.

Depends if it is a fast charger or just a plain old trickle charger. Nicd fast charger isn't quite right for nimh. Likely to overcharge; the peak detect mechanism is different.

I know that feeling! I'm 20 years in now... hooked acromion, so no overhead lifts of note, I used to like the olympic lifts but they don't like me slightly dodgy disc somewhere means I'm very gun shy on squat and deadlift, its all higher reps now something dodgy with ligaments in shoulder so have to be super careful of form on bench despite that - keeping form tight and maintaining strength as long as I can is the goal now. age is certain... like taxes... I guess 😀

Awe inspiring build David.

Good effort with the stone, must be 100kg or over, they are extraordinarily tricky to lift with that shape, I could never get to grips (sorry) with the technique for the first part of the lift. I still keep up the gym lifting - mostly focussed on the regular powerlifting bar lifts. Managed to get a 550kg total in my late 30s. Sadly I think trying to repeat that would probably bury me these days.

Snap! Although the arrival of kids somewhat put a stop to the skiing holidays... 🙃