425 FBL CF TT with BeastX maidened.

[ukgroucho]

Well it took me a while but I maidened the 425 FBL at the weekend. A few teething problems, one of which I still need to deal with.

When it was going well it was fantastic... even on pretty much factory settings for the BeastX controller it flies like it is on rails. I initially had a problem getting the tail to behave... that turned out to be a mistake on my part (mechanical issue). I still flew 4 packs on Sunday settting up and playing and it's a blast. Even with the smaller of the two pinions included in the kit (13t or 14t?) it gets a decent HS (2500 - 2600) using the governor on the Gaui ESC.

This is the stock Gaui 1400Kv motor and 60A ESC. I decided not to use the SBEC in the Gaui ESC as I'm running high torque digital servos and don't want to risk overloading the 3 amp unit that is built in. I'm actually very impressed with the power from the motor and the behaviour of the governor (and I've got a bunch of Kontronik ESCs which are reckoned to be one of the better governors around).

Anyway, went out yesterday to tune the tail more after sorting the mechanical issue out and hit some issues (cyclic gain seemed to be out, so I start trying to fix that ...). Finally after several flights, landings , etc. I realize that the OWB is slipping and causing the governor to pulse, which is upsetting the whole rig. From what I can tell it's the bearing spinning in the drive gear rather than the bearing being defective. I'll pull it apart and inspect then reassemble with Loctite 648 if all looks good.

More reports later.

[Mikej]

Looks good Jon - I have a Beastx on the way, but it will probably start off on my Mini Titan or Trex 450

[ukgroucho]

I have a second BeastX here and an Outrage G5 FBL kit for it to live in.... but I have to confess that after the great experience on Saturday with the 425 FBL I was looking at my 550 and thinking evil thoughts.
Maybe I'll just have to get a third one....

Oh, by the way... yours SHOULD come with the latest firmware... but I have a USB cable for the BeastX if you need to update it. (I did the original pre-oredr and they included a USB cable as a sweetener).

[ukgroucho]

OK so I have had some more time with the 425 FBL ... and had some ups and downs.

Went out Monday to do some tuning - back to back flights, and it started misbehaving. Was trying to tune the tail and still had a nasty vibe. But it also started nodding at the head... which (of course) I took that to be a tuning issue with the BeastX.. so I tried to tune it. Eventually I realised that the heli just did not SOUND right, and it was down on power.
Figured the one way bearing was duff and was starting to slip when hot (remember, back to back flights) so this was causing governot to pulse. Because of the way it felt when I held the head and turned the motor by hand it seemed that the bearing was turning in the gear. I dutifully dismantled the OWB and rebuilt it - but reinstalled with a new 20t OWB I had to hand (incidentally the stock unit is 19t).
Did not fix the issue.... more investigation showed that it was the motor shaft spinning 'free' from the windings. EHHH?
Pulled it apart and found that the motor had not been assembled correctly. Gaui 1400Kv 504 motor (for those wondering).. Pretty impressed with the motor, NOT impressed with the quality control!

The top plate had not been popped on correctly - there was a small gap - so the grub screw did not hit the incut in the motor shaft - it was a few millimeters too high up the shaft. Pushed the end plate on properly, reassembled and problem fixed.

Next the vibration... this was upsetting the BeastZ... the tail fin was doing a merry dance. I tried a bunch of stuff.. different blades, spooling up without main blades etc. etc. to try to track it down. I was getting MAJORLY frustrated.
Eventually I swapped in the tail blades from my 550 (K&B flouro yellow 'stiffies') ... problem fixed... the POS tail blades that were shipped with the 425 were causing the issue.
After all that I had one decent flight this evening... although I had to tweak tail gain a little. Now I am ready to go thru the setup of the BeastX in more detail and fine tune... although it did fly just LOVELY even with my 'guesstimate' settings (remember I messed with the head settings when I thought they were going adrift 'cos if the motor issue). I'm amazed that my "I think it was like this" settings in the BeastX resulted in such a smooth flight.

Hope to get out tomorrow, but overall very happy with the BeastX, very impressed with the Gaui motor and ESC (apart from the motor assembly issue) and delighted with teh Gaui 425 FBL CF frame and head.

[Mikej]

Jon,

It's only in my 450 - but I'm amazed by the Beastx - flying in the last few day's winds 15 - 20mph gusts and the heli feels like it is flying on a calm day. I've just done the standard set-up to get everything moving in the correct direction and that's it other than tweaking the tail gain - soooooo easy.

Enjoy

Mike.

P.S. I love the flybar-less look - so clean

[ukgroucho]

I did a bunch of setup flights late this afternoon in gusty conditions and the 425 just shrugged it off.

The biggest issue is that I think to really tune it (for me) I need calmer conditions so that I can tell what is the controller and what is the weather. Nothing that the controller has done so far has been radical enough for me to point and say "flybarless controller issue". In rough weather it is doing a great job of sorting out the buffeting and the heli is ripping thru it all.

[ukgroucho]

Well it turns out that I was optimistic about the Gaui motor. After getting the 425 to fly really nicely I started getting more issues. More vibes, oscillating head, would not hold altiitude (bobbing). Once again I tried to tune these out on the BeastX... but nothing to do with the FBL controller.

More painful diagnosis and I found that the Gaui 504 is knackered. The original issue with it not being assembled correctly must have done some damage to the top of the bell housing, because now when you spool up the bell canters over slightly and binds on the static part of the case (and rubs the magnets on the windings as I discovered when I disassembled it). The binding is causing vibes and, no doubt, making the governor pulse.
Absolute crap! No way I can easily get this fixed... maybe I'll try to send it back to Gaui but I doubt they will do anything.
In the meantime I ordered a Scorpion 3026/1400Kv - that looks like a suitable replacement.

[ukgroucho]

I think I figured out what the damage is...

Because the set screw that holds the bell housing onto the top of the motor shaft was not fitted correctly when the motor was assembled, it was allowing the shaft to spin in the bell housing. This caused some of the initial vibe and (on repeated back to back packs) loss of power issues.
Spinning the shaft in the bell housing has worn the motor shaft hole in the top of the housing a bit - probably just a tiny bit - so the hole where the shaft passes through and mounts is a little sloppy. Enough to allow it to cant over slightly when the motor spools up. So then at the bottom of the bell housing it binds on the casing and the magnets.

Sloppy sloppy QC by Gaui... if only I'd spotted this early on I could have reassembled it correctly. Now it's knackered... the bell housing cannot be repaired (no way to add back the worn stuff).

If anyone has a burned up 504 1400Kv let me know. The windings in mine are just fine so we could come to an arrangement to bring together a good set of windings and a undamaged bell. Although I do wonder about the bearings in mine now...

[Mikej]

Jon,

You probably already know, but that motor is a bit of an amp hog apparently and some poeple have found that it can run very hot ...

From the Scorpion web-site

Scorpion HK-3026-1210KV
No-Load Current(Io/10V) 1.63 Amps
Motor Resistance (Rm) 0.018 Ohms
Max Continuous Current 65 Amps
Max Continuous Power 1365 Watts

Scorpion HK-3026-1400KV
No-Load Current(Io/10V) 3.33 Amps
Motor Resistance (Rm) 0.010 Ohms
Max Continuous Current 80 Amps
Max Continuous Power 1680 Watts


Scorpion HK-3026-1600KV
No-Load Current(Io/10V) 1.9 Amps
Motor Resistance (Rm) 0.016 Ohms
Max Continuous Current 70 Amps
Max Continuous Power 1470 Watts

[ukgroucho]

Yeah... but it's the closest match to the Gaui 1400Kv I coudl find in a hurry... 1680watts and 1400Kv.

Biggest concern is if the Gaui ESC is up to the job - both in terms of the governor being able to run the motor nicely and also the peak amps.
It's on the 425 Flybarless - so less losses in the head, and I'm running the smaller of the two pinions that came with the kit so slightly lower gearing.

We'll see what is what on Sunday... motor should arrive tomorrow as I paid for next day courier from Fastlad

[Mikej]

If it doesn't arrive let me know - I have a couple of spare cheapo motors that might work

[ukgroucho]

Will do .. thanks!

[torana74]

Jon, i've had good success with the Z20 1470 with 500's. Should be great on a 425 setup.
Think it might be more efficient than the 3026 from other's reports.

The Beast is sounding AWESOME How good is the tail holding??


Vas

[ukgroucho]

Tail was holding just fine until the motor started screwing things up. I had it flying just LOVELY with the original motor until I pushed it with back to back packs and then the heat caused the original construction issue to start showing up.. shaft was spinning in the bell housing. Had to go thru some setup stuff to balance gain with the settings in the BeastX but no biggie... and I'm running K&B rappie 30/50 tail blades so I had to drop the gain a bit.

Took me a while to work out what was going on. Initially it looked like a OWB issue (seen that before). But I think I took too long to work it out and it has reamed the bell shaft 'tunnel' at the top and fubared the tolerances.

It's a shame because that 504 1400Kv motor is very nice... not the best design and QC issues but the power was just fine (VERY fine) and it came down cool.

Have the Scorpion now and (sure enough) it's fixed the mad BeastX wobble issue. Not had time to do more than a couple of test hovers and pitch pumps in the garden but I am worried about peak amps.

Just started rigging an CC 85 HV that I have lying around (needed connectors) but I ran out of solder.. will sort that out tomorrow. It's a bit big but I'd rather strap that to the side of the frame than explode the Gaui 60 Amp ESC that came with the kit. Gotta deal with the CC governor now (which has NEVER impressed me.. the Gaui one did.. almost as good as a Kontronik).

[torana74]

update the CC to the latest firmware. Gov has got quite reasonable. I use set rpm mode on mine and have played with the gov gain to get right. But only see about a 50 rpm difference.

Keep us updated. It really sounds like it's going to rock.

Vas

[ukgroucho]

So I tried the CC85 HV today and it was the (expected ) nightmare. Bottom line is that I could NOT get it to fly the 425 successfully.

I went thru the painful endpoint setup nonsense (connect a laptop in the field the CC USB connector, struggle to read laptop screen. fudge into fixed endpoint mode blah blah). Did all that crap and then wanted governor (reconnect to CC USB, mess around giving it motor and battery spec on a laptop screen I can barely read in the light conditions).
Set it up at 0 pitch to get 2600 HS, try to take off .... and it cuts out / sags. I went thru a bunch of BS settings - current limiting, fixed throttle instead of governor etc ETC! and basically wasted a BUNCH of time at the field trying to get this POS CC85 HV to work. Always it would cut out as soon as I applied power beyond hover.

Stuck the Gaui 60 Amp back on and it worked as expected... did some circuits etc. BeastX needs more setup but I'll get to that when I am confident in the power system.
My concern is that a pitch pump with the Scorpion motor showed 73 amps.. Gaui ESC is 60 amps with a 70 or 75 amp max.... bottom line is that it is not enough. And the CC85 HV is a waste of time.

I've messed with CC ESCs in the past (10, 25 and 35s) and come a croper with them. Either the heli mode stuff (governor) was BS or the BEC would freak out. This experience was no different..... CC ESCs suck. Even the little Gaui 60 amp was better.

Gonna buy a Kontronik or similar...

[torana74]

Jon sorry to hear that mate. I agree the CC's can be fiddly but once the head is around them, work quite well. The learning throttle limts,,,, and then relearning once changing modes/enabling auto rotation etc is a pain. Also the built in bec doesn't quite do the 5amp as advertised i've found, but should do fine with 3D on 425's, sports on 550's

The Kontronik rocks... though i've had two give up for no reason. The gov is the best and the bec IS 5amp.. Just hard to justify the price. I've been lucky with my CC's. One has gone for warranty but the others still going strong. And i love the data log.

Hope you get ontop of it mate

Vas

[ukgroucho]

I'll give the CC one more try in outrunner mode. I'll also stick the Eagletree in line to see if I can figure what is happening with amp draw.

But it is an old CC85HV... had it sitting here for two years unused. It's an OPTO unit so no BEC (using a hyperion 10 amp SBEC) and it's pretty big when strapped on the side of the 425.

Kontronik Jive 80+ LV is looking attractive right now... apart from the price.

[ukgroucho]

Got the Kontronik Jive 80+ LV fitted. Dialed in a HS of ~2600 and WOOHOO.

I need to go back around the whole setup of the BeastX again but it still flew pretty nicely, not quite settling as it comes out of hard cyclic manouvers (flips etc) but nothing unmanageable. I can dial that out when I have some time and a bit more light... was loosing it this evening when I was testing.

Scorpion definitely gets hotter than the Gaui motor did - that Gaui 1400Kv motor is a pretty good rig, shame mine was put together wrong in the first place.
Scorpion is definitely doing the business from a power perspective... in fact I had to dial it back quite a bit on the governor as initially I had over 3000 HS

[ukgroucho]

Ohh and another nice thing about the Kontronik (apart from the fact that it works easily and first time) is that the SBEC is 5 amps continuous with 15 amp peaks so I removed the Hyperion 10 amp BEC....