700 tail blade holder fails

[hawkwell]

sorry to have seen your helli in bits tony i know how much time you spend over maintainance and your one of the safest flyers i know but sometimes these tiny fractures go unseen. i am shocked that under the enormous stress these parts are subjected to there are not more breaking.
you will soon have it back together and inverted 3 inches above the grass

see you at the field

[Matt Gill]

I fly 2x 700's and both mine have suffered from what Sesame has described. - Blade holder thrown off mid flight (the bolt that holds the holder on to the hub, sheared at the head).

The first time it happened, it caught me by surprise and I thought it was just bad luck on my part and maybe I had over tightened the bolt somewhat. However, for peace of minds sake I stripped my second machine down, re-greased the tail thurst bearings and re loctited everything and got a friend to check that everything looked and felt ok....... Week later, that machine (the one I had stripped) did exactly the same thing (luckily I managed to save it this time... complete fluke let me tell you ).

So... I have spent a few quid on getting the Quick UK upgrade tail grips and hubs and had about 10 gallons on each heli, with absolutely no problems at all. Speaking from experience and in my opinion, I would certainly put the upgraded tail grips on a 700 or at the very least use maybe a JR M3 bolt to hold the holder onto the hub. (Aligh and JR bolts might come from the same factory, but peace of mind counts for a lot in this hobby and I am not really a fan of align cheese bolts in the first place.) However, it is important to note that I have seen countless, miles better pilots in my club and around the country absoltuely nail their 700's with no problems whatsoever and a lot of people have never had the issue that I have had and you descrbied, so who knows.... maybe it is bad luck.

The good news in though, is that mine are both flying again and I am confident that I will not have the problem again, so that counts for a lot. Be interested to know what you decide to do...

matt

[Tim Procter]

However, it is important to note that I have seen countless, miles better pilots in my club and around the country absoltuely nail their 700's with no problems whatsoever

Matt

Andy Hornyak was telling me on Friday he tried in vain to crash your helis on the Saturday at Waterfoot and only managed to bugger his own up.



Seriously the Quick UK upgrade sounds like a good decision after reading this thread Tony.

[Sesame]

Hi Gary nice to see ya on here.

yup im leaning more n more towards the quick tailgrips, like the idea of swapping the bolts too, later ill finish checking her over and get ordered up tomorrow, anyone know where there are some 8900 gears going , having a little job finding any,.

[Matt Gill]

Tim... You do take confidence from seeing your machines thrown around the sky about 2 inches from the ground and then survive. ... he nailed them saturday and Sunday, after both his had been buried. It was slightly easier to relax on the Sunday with the hangovers we had..

Sesame - PM sent.

[jiberjaber]

What is the difference between a JR and align tail bolt then? Can I just put in a modelfixings M3x8mm bolts? As long as it's HT steel then it should be OK shouldn't it?

It is certainly tempting to buy a new metal hub and grips on the basis that 20 quid or so spent might save 200 odd quid... hmmm...

[Mart61]

Crikey - quote an "in" there Tony!

Sorry to hear this.

[Matt Gill]

jiberjaber... there probably is no difference between an align or a JR bolt. However, after having two failures, your faith in certain bolts diminishes rapidly. I have flown JR Vibes and never had any issues, so I guess I hold JR quality in higher esteem than I do Align... you get what you pay for. (Incidentally, I really like my 700's!!). However, as I suggested in my post, both bolts are probably made in the same factory, so it comes down to peace of mind and being comfortable with your equipment.

I thought it was just me who had this issue happen, but when I saw the post, I just thought I would add my comments. Plenty of pilots fly the original bolts with the plastic blade grips with no issues at all, but as you say, it might be worth spending £50 to save a £200+ crash and have that peace of mind, or change the bolt!

[t-rex pedro]

I just fitted the QUK tail grips. Lovely bits of kit.

[Matt Gill]

They really are a great bit of kit. The good news is you can buy the internals (bearings etc.) and hubs individually, so in the event of a crash, parts are easy to come buy and relatively cheap to repair. Saying that, I have crashed a few times and never had to replace a hub / QUK tail blade holder. (Think I might just have jinxed myself)...

[raptorheli2]

matt, i think most of the 700's in our club use the QUK grips now? i upgraded both of mine when your first one let go. but if you remember align redesigned the tail spindle which meant one of the QUK tails came clean off....DOH.

cheers

[jiberjaber]

I will keep an eye on it all then, I think I will strip the tail this week sometime if the weather turns and replace the bolts to be on teh safe side, I have plenty of Modelfixings and Compass M3x8 kicking around, so no shortage of choice.

[Sesame]

Got all my bits yesterday and started the rebuild.

Got to say the 8900g are ded easy servos to change the gears on, and the 700 is a pleasure to work on, no stupid little bolts you cant hold properly. tonight hope to get the boom finished and the head back on, finish it off tomorrow as there are a couple of bits ive decided to change so they should be in the post tomorrow, ready for the weekend.

when I was taking the front gearbox apart for the tail I did notice quite alot of wear on the crown gears which ive changed, I dont think its crash damage, but as I said definate wear going on something ill have to keep an eye on.