View Full Version : Al's TDR Project
05-11-2012, 10:52 PM
Yes you are correct, used some other silicon grease for that, this stuff looks good for the gears too.
Cant remember who, someone else mentioned they used it too for lubing the gears, this stuff I can get down at the bay locally at the Scuba shop.
05-12-2012, 12:50 AM
I have a tub that I bought in 1997 for the O-Rings in my scuba gear. That's 1997 not 2007. It just never empties...
05-12-2012, 08:27 AM
That the Maiden flight then, went absolutely perfect, spooled up, increased collective, into an almost hands free hover, tail working perfectly and flew around for a while great, unbelievably stable what a machine, some photos below.
But.....Joined the "Lets do something stupid and wreck the TDR" club :face
Second flight, started the same, some flips rolls gentle stuff, then I lost it! Went into a banked turn that was obviously too far and low, only one mistake in the bank and I made two. Lost orientation for a second and pushed in the wrong correction, I relive the moment but alas no time machine, just very angry with myself.
Lessons learned, respect the speed and keep within a height distance line of at least 30 degrees, this heli can cover a lot of sky so needs accounting for. Mybe I am not quite ready for it yet so need to take it easier.
Damage assessed and not alarming at all:
Blades of course including Tail
Main shaft gear stripped
Canopy skuff and small crack, pealed of decals using hot water, easily repaired touched up and new decals.
Most of the ball links gave up and saved the servos.
1 skid plate and 1 bent skid.
1 Flybar link guide
1 lower side frame
Cost about 170 Euros + Main blades - expensive day out - telling the wife dismantling for fun!
Boom survived without a scratch, surprised, I went in almost knife edge, blades took it then skided along the canopy so a glancing blow, expect the canopy flexed like hell and saved a lot.
Stripped the head and mechanics, nothing bent at all, all servos check under stress, full travel, no apparent damage. Very lucky I think, into this again since January, lots of flights on my 550 but first crash had to be this one, just a setback, parts ordered, back in the air soon :thumbup:
PS blame Groucho, saying all was smooth here lol
05-12-2012, 09:24 AM
That's too bad. I feel sorry for you. :hug:
I would advice you to excange the main shaft while you're at it, just as a precaution.
It is a cheap "insurance", imo.
05-12-2012, 09:37 AM
Yes agree, ordered it and feathering shaft with end bolts, cant be too careful.
05-12-2012, 09:41 AM
:hug: Same here.
I had the same problem in the beginning of TDR flying.
This lady covers a lot of sky very quickly.
This is really a point where I had to get used to.
She just speeds silently away . . .
05-12-2012, 10:37 AM
I'm actually really quite upset after reading of your misfortune...
It all sounded so promising before you said 'But'...
Could I maybe suggest you give some thought to installing an SK-720?
Things may turn out differently next time something like this is about to happen with the SK-720 helping out...
05-12-2012, 10:56 AM
Lol, just after that did occur to me, self leveling, however, shouldnt have been so stupid but thanks, very happy with it despite the setback, playing to an audience was probably a factor too! (Jan does warn about that).
Boom didnt escape after all, stripped it and creased slightly where it clamps in the frames, luckily managed to get the TT and bearings out smoothly. Have a spare so no problem.
Boom and skids rebuilt, spare gear bolted on, another week for the parts and rewind to square one :-)
05-12-2012, 07:41 PM
Words can't express the frustration I feel for you after such careful build and set up - well they can but I can't type them on a PG-13 forum !!!
My fave helis - all 700es have all had mishaps on the first few flights - almost like a christening and gone on from strength to strength after
05-12-2012, 11:52 PM
Thanks John and all for the support, appreciated.
A few beers last night got me over the "trauma" and off to fly the 550
Order for parts is off and total cost with blades is about 300 Euros, so thats a 10% hit, not that bad really, main shaft bearings not 100% so ordered them too.
Canopy to touch up, suppose I need a small amount of GF/resin, body filler and spray paint, decals with the spares, not one of my better skills, its all black so hopefully easier.
Pleased that it did fly straight off and nicely and there was not a technical problem, in fact married up Jlog and Vbar logs, found the flight from reset to "Aileron sensor out of range" etc, nothing to worry about.
So we can fix the Heli and do something about Dumb thumbs to fly another day.
I talked about the "Bath tub Curve" in one thread, higher probability of technical failure at the start and end of life. Obviously applies at the start to flying skills then. Take it extra easy for a while.
But thanks again. :hug:
05-13-2012, 09:36 AM
For those interested in the log analysis in general, found it easy to tie in the Jlog and Vbar to see what exactly went on with the electronics. I worked back from the crash which shows sensors out of range and used the boot-up timing which of course will be the same.
Maiden flight was very calm, hardly any Vbar groans at all, Jlog shows that I switched into Flt Mode 2 head spead twice.
Second flight was a bit more lively with raised vibration levels, did a few consecutive flips then 2 half rolls, pausing inverted which shows as 2 peaks on Jlog before the big peak where we hit the deck. Jlog shows a few seconds delay before hitting TH which is not a good thing, also reason why I had a shredded main shaft gear, motor running fine though.
Vbar shows voltage problems at the end after a few reboots, they were due to anxious avionics checks and stressing the servos under load to check for bad gears, that was done with a small battery pack. Vbar also shows complete lack of signal after the crash, I was at least 500m away so line of site problem there when on the ground. Recieve path checked out good, will obviously do a full range check when I put it back together.
05-14-2012, 07:27 AM
Great service by Jan, parts on the way, forgot that the Fore/Aft Servo link was slightly longer and asked for one with the order, Jan put one in with the invoice becouse it was packed already, early this morning!
Canopy repaired this morning, minor fibre glass patch inside, just filling, rubbing down and a minor paint job before new decals and its as good as new.
05-16-2012, 10:36 AM
Shouldnt be too long now, not holding my breath for this weekend, if parts dont arrive tomorrow, prefer they do so early next week, no temptation to rush it!
Although wont take long to fit the new parts, want a complete check over everything again.
Replacing the main shaft bearings, have an idea for those, use my pillar drill as a press, centering the bearings with the old mainshaft in the chuck and CA old bearing to shaft flush with the bottom of the chuck, the old bearing will apply even pressure downwards. Will heat up the bearing mounts first, a little machine oil on the new bearing case and sqeeze em in.
Canopy looking good as new, 2 small fibreglass patches inside, some filler then an hour or so of wet&dry ending up with 600 grade, finally sprayed with auto black gloss, you cannot see the difference, blended in under where the new decals will go. These canopies are really easy to repair, saved 80 Euros.
05-18-2012, 02:42 PM
Still waiting so looks like another week out of action but then I will have more time next week to re-assemble and check the mechanical alignment.
A thought came to mind after inspecting the boom, slight bend and definately over enthusiastic when tightening the boom clamps, old boom has a definate indent where it was clamped.
So, calibrated the clamps! Cut a section of the old boom off, now you cannot rotate a complete boom because of the 2 screws holding on the front gear assembly. Now, had both clamps free, tightened the front clamp until it would not rotate by moderate force, then another quarter turn, could not now rotate with a lot of force. Loosened by 2 turns exactly, then repeat for the rear clamp.
When I mount the complete boom, its 2 turns of the nut exactly and content in the knowledge its enough to hold it firmly.
Well as a project I felt this went very smoothly, easy to build as long as instructions are followed. The swash alignment blocks are great, you can actually get the setup very close if you use them during the build, ie make up the links, mount the swash and rotor etc, checking with the swash spacers as you go. The maiden was textbook and into an almost handsfree hover on lift off and a bit of FF showed no surprises. Shame about the bloody prang second go and annoying at the time, first crash since I strarted this again last Jan/Feb but hopefully paid my dues for a while!
I hope this thread may be helpful, not too much original, maybe the CF bracket and simple servo/power bus that worked out well, but great fun all the same. Probably a fair conclusion to this thread now, be back in the air by next weekend so hopefully no more dramas.
05-18-2012, 04:07 PM
Been a great thread :noteworthy
Good point about the boom clamps, overtightening can make TT bearing blocks run rough and also increase vibe transmission from the TT to the frame, dont need nearly as much clamping as with a belt drive.
No need for any sort of press with alloy bearing blocks, just heat to 130C and they just fall out and the new ones slip in :)
05-20-2012, 08:07 AM
Thanks John not much doing here, DHL employing slugs on valium, a bit dissapointed with the mail may have to pay extra next time, but hopefully not too soon. Only discovered that I had a damaged servo horn the other day, those BLS 451 horns are great, all the splines got taken out on one instead of servo gears, however, checked the gears anyway, impressed how "agricultural" they are. Got a few spare horns from a friend so cut and fitted, hopefully get mail early next week.
05-23-2012, 11:42 AM
This must be the thread conclusion!
Yahoo, got the parts today and carefully fitted and checked the setup, no problem. Reset the Helijive again to make sure.
Spooled up, hmm sounds fast, JLog and Phone shows 1850 on a 50% pack, WTF. Further analysis shows throttle 100% input on the log.
Put a servo on throttle O/P, all is well, pulled up Mels video and 5 mins in dawned on me :arggg:
I hode reset and calibrated mode 4 with my Normal start up curve Doh 0-30-30-30-30.
The Jive saw 30% as 100%. So put linear curve in TX 0-100%, Mode 1, Mode 4, TH, all is once again wonderful!
Thought I would mention that, easy to forget and get into trouble I suggest
Main bearings easy to change, heat up the blocks, I did use a pillar drill to push them in dead square with a main shaft, old bearing and screw through the shaft hole, not much force needed at all.
Black plastic rotor link guides, also easy, expected more resistance but a slight interference fit only for the 2mm pins, pulled back about 5mm and put Locktite on the pin with a needle where the hub has a split, worked some in a few times, now stuck fast.
All good for the weekend. :clappp
05-27-2012, 10:10 AM
Thread conclusion except to say what a fantastic weekend, TDR now flying like a dream, a bit intimidating when all the other Heli flyers stop and pull up a seat to watch. However taking it really easy, enjoying almost ghosting around at 1400 RPM but with big sky manouvres, fantastish!
Also maidened my Logo 500SE, another great machine, flew perfect from the word go!
Align 550 now taking a back seat, see what you mean, yuck! Loved it but seen the light now with 2 great machines, still warm up with the 550 but it has become my "beater" and will try new stuff on that first lol.