A fresh set of 3 Emax ES08MD II servo’s landed – along with a new FBL head as the original servo (Emax ES08DE) got trashed when the elevator servo let go –
I went with the slightly different model of Emax servo’s for a few reasons – The originals I got second hand …possibly 3rd hand on an obviously crashed more than a few times heli – as well as me crashing it big time at least twice before I went with the new frame and flybarless setup – so they were OK servo’s considering their price (can get them for not much more than £3 each!) – the only reason it gave way was a cog has stripped a few teeth – possibly due to the previous crashes, but maybe because flybarless does cause a little extra strain on servos?
The newer ES08MD II’s have all metal gears, so /should/ be a bit more robust as far as teeth are concerned – but will possibly wear and get sloppy with play a bit sooner, this is something I’m not that worried about as they were again silly cheap (less than a fiver each) and I am sure to do major damage to them long before they get too sloppy to fly with
I stripped the heli down to a bare frame and installed the new servo’s – the arms were the same as the old ones – and it just took a bit of a tweak in software to get the arms pointing at 90 degrees to the main shaft, the cables seem to be the same length and come out of the body at the same place and angles so nothing to report as far as installing them goes
I stripped, lubed and thread locked the new flybarless head together and left it overnight to cure- not terribly impressed with the follower arms as they do not allow the bolts to be tightened up without them being crushed against the head and locking up, but a dab of thread lock and careful torquing whilst checking for binding and allowing enough time for the thread lock to do its thing seems to be a good enough solution for now
I have stuck with the std CopterX feathering shaft and dampers (waaay softer than the hard POM ones I was running so I expect a much less direct feel and I expect I will bend the feathering shaft first blade strike or hard landing!)
I had to rebuild the tail with a new boom and belt as the crash had snapped the boom and de-toothed the belt, other than that – all seems OK, Align feathering shaft snapped in two, but the mainshaft still runs perfectly straight – the main blades seem to have survived being ejected and still in balance
I then went through the laborious task of setting the blade pitches and angles up in software , this time I opted for +10 and -10 degrees max for collective pitch and a max of +6 -6 degrees for elevator and aileron – I tested the swash for bind and its silky smooth throughout and no chance of servo arms hitting or fouling anything – I /think/ I was running +-11 for collective and +-8 for ail/ele
I spooled her up and she popped into the air without drama, have flown a few packs since and its again VERY stable and no where near as reactive as it was, I don’t know if this is the reduced aileron and elevator travel, or if its the compliant feathering shaft dampers or a setting on the Tarot ZYX-S2 controller, but its a LOT softer to fly – definitely no need for DR or expo!
Whatever – it flies and seems like a happy stable heli once more, no wags or bobbing, but then I have been flying it VERY gently and sedately as I deserve some actual flying time after all the benchtime its taken up!
Happy with the Emax ES08MD II’s so far
The 450 heli will get similar I think 😀