T-Rex600 Rebuild....

[copterboy]

Now I got the new clutch ordered, I am going to drop the engine tonight and get it cleaned up. Clutch should arrive this Friday, so going to contact some guys from the club and see what day they are there. Gaz tells me most of the heli members go Sunday. This Sundays forecast is more rain, but Saturday maybe ok. Now in a dilemma whether to go try it again on Saturday, as I maybe on my own

I just wanted to say, considering my lack of experience with nitro's, I feel a slight confidence boost in that I diagnosed the problem with the clutch correctly. Still, I think my lack of experience probably caused the problem

Just want to make sure I don't ruin another, so I'll have to put this down as another lesson learnt.

[Tomstoy2]

Denis, do you realize you thread on this is now 55 pages?

One would think you should have learned something by now! !

[copterboy]

Now you mention it Tom There's probably 50 pages of twaddle and 5 pages of useful information

I guess I've learnt as much as I can mechanically, but as I'm sure you know, until you start flying it, there is a whole lot more to learn about tuning the engine (and then setting up the gov if you have one, which I do). It is rather shameful though after this amout of time, I'm still only upto that stage

Just got confirmation the parts are picked and being dispatched today I'm off to the field for another go with the 450. It's blue skies and not a breath of wind at the moment

[copterboy]

It was going well, but I just uncovered some damage to top of the fan. Think it may need replacing, as I guess it's now unbalanced and maybe a cause of vibes? What do you guys think?

[jperkosk]

Yep, I'd change the whole assembly, it's not that expensive...

[ragge1]

convert it to electric

[copterboy]

Originally Posted by ragge1

convert it to electric

Noooooo...not yet anyway

Think I might miss out this weekend because of the extra spares needed. Just realised I may have a cash flow problem, as I got to buy some materials today for a job on Monday!!

Hope it doesn't keep me from flying this weekend, even if I go to the LHS for spares tomorrow and rebuild it, Sundays weather is still rubbish. So I might just crack on with work so I can get the stuff I want on Tuesday, and have it ready in good time for the FFF. Might be for the best if I ground myself until then anyway, only way to guarantee I'll have something to fly

[copterboy]

My new fan assembly just arrived. So I can finally get it ready for another test flight.

Didn't realise the new fan assembly had a plastic fan, so I'm a bit dissapointed. I didn't even think to check, as all I know is it has a metal one since I bought it Should have realised from the price though.

The new assembly also has the ducting. I decided to go for this as a couple of screws that clamp the ducting to the frame don't fully tighten on the existing assembly, so gives me cause for concern over vibes.

So my plan was to replace it all, but now i'm left with a plastic fan I wonder if I will need to upgrade again in future, and no new screws, so still at risk of vibes.

I'll just put the stock parts on for now, and give it another go If I can just get it to a point where I can put a full tank through it at weekend I'll be a happy man again

[jperkosk]

Nothing wrong with the stock plastic fan, Denis, I think it gets a bad rap from the bling guys for being, well, plastic. Never understood how it could cause vibrations, it's quite small and weights next to nothing True, durability may be en issue. I have an engine to drop myself on #2 600N that I've recently grounded because it has developed some strange noise that may be coming from the fan, but that bird has probably >200 flights on it, as I prefer how it flies over the #1 600N. But causing a vibration? BS, IMHO.

[copterboy]

@Jerry, I guess the saying fly it stock until you know your flying demands it applies, I just didn't know any different.

I think I just have some bizarre upgrade habit, probably due to owning a belt-cp. You know what they say, you start off on belt's, then you go onto harder Align's, Outrage's, Avant's, mixing them at the same time with FBL, HD and scale options. Some of the hardcore users even end up going onto MRH's and AP's There is no known cure

I'm not saying it's the fan that will cause vibes BTW. It's the big plastic fan ducting that is not secured properly. The hexagonal bars from inside the moulding have been stripped by the screws being tightened too much, as long as I can remember, they just keep turning when I screw them in. Now I opened up the new one and had a look, I've got the new hexagonal pieces in the kit, so I was actually moaning about something that is no longer a problem, I can get all 4 screws to bite again

[sutty]

By the way Denis, if it should ever happen again, where you have stripped the threads in a moulded plastic tube, I have found that placing a cable tie, of just the right size, down into the hole, before putting in the screw, will end up tightening that hole to the point where it is almost as good as it ever was. Just before you nip it up tight, you can whip off the end of the cable tie with your hobby knife, flush with the surface, and then finish off tightening it. The tie, when pressed into the side, and made curved by the screw, should probably take up about a third of the circumference of the hole itself, to be tight, but without busting the hole.


Cheers

Sutty

[copterboy]

Thanks for the tip Sutty. I have used a similar trick with matches in woodwork (with the striking head removed of course).

At least the old part isn't damaged, so will go in my spares box for when the inevitable happens

[Luke Warmwater]

Originally Posted by copterboy

Thanks for the tip Sutty. I have used a similar trick with matches in woodwork (with the striking head removed of course).

My shed door now opens and closes perfectly thanks to the addition of a couple of matches in "worn" screw holes!

[dauste]

Originally Posted by Luke Warmwater

My shed door now opens and closes perfectly thanks to the addition of a couple of matches in "worn" screw holes!

I mentioned this technique to the wife, but she said 'NO'!

[copterboy]

I have spent best part of today messing about with the engine fan/clutch/clutch bell etc.

I'm now stuck re-assembling the clutch bell. The bearings on the shaft just don't seem to want to line up with the plastic frame mount Obviously, there is some sipple method or technique to it, I'm not yet aware of, which the manual probably won't explain clearly in a simple exploded diagram. I'm sooo frustrated I feel like smashing it up and throwing it away.

I just want to go and fly this f*cking thing and I'm still struggling to get the last couple of bits back together It's 5 o'clock and I've still not left for the FFFD. By the time I've packed the van and got ready, it's gonna be dark by the time I get there now I've got to the point where I'm just going to throw it in a box, take it down there, get pissed and let off some steam, will get someone to look at it with me tonight, and hopefully start a fresh tomorrow.

Rant over.....sorry for swearing but felt I had to!!

[ragge1]

sell it and get an electrical 600 size , save lots of
Logo600sx maybe

[Luke Warmwater]

Do they still make those old fashioned nitro things?

[copterboy]

@Ragge and Luke. You know a bigger Eheli is in my future plans, but for now I am happy to stick with this, whilst I get used to the size and presence. Plus I want to get current projects finished, before taking on anymore

Notice how I automatically stand too close, standing futher back and flying further out are the first things I learnt. As I punched up and down, it felt like the heli was almost on top of me, and I find looking up at something right above me can make me feel a little dizzy, so I will definatley have to take it further out and stand further back in future!

In the first few seconds of the 4th Test vid (on the FFFD thread) you may notice the change in throttle when I turned off TH, and the engine was just ideling. The TH curve was adjusted from 11.5% down to 9%, so in this vid it now matches the idel position of the normal curve. The heli did need some fwd ELEV trim, and right AIL trim, but I managed to do it after the second and 4th correction, within a few seconds.

Well you know the rest of it, as I take off here, the mixture screw was adjusted by Gaz, and I forgot to re-do the RCBooya bolts. At the end of the vid, you here me mention 'I'm sure I saw something...'. The words fall off are just cut off where the recording stops

You will notice I am bobbing up and down alot, and to me the engine seemed slow to respond. At first it was because I wasn't i idel up, but even then it didn't feel as sharp as I feel I could handle. Sutty questioned me on it in the last garden hover vid, and at the time I said it was deliberate to get a feel for it. Well, I didn't like the feel of it at the field as it just didn't respond to pumping the pitch, then it would jump up too quickly. Decided to check my pitch curves. I normally like the 450 with a flatter throttle curve, so I'm changing the 600 throttle curve from 100-85-65-85-100 to 97-87-77-87-97. Should give me a higher headspeed in a hover, so more responsive to pitch pumps. Plus should stop me from doing all this bobbing up and down, and give the throttle stick an even response changing from up to down, and vice-versa.

So, here goes....nothing spectacular but I feel I am feeling more confident with it. The fact it is a bigger heli and a NITRO stills scares the cr4p out of me!!

[copterboy]

Servo's arrived safe and sound Thanks again for the loan Andy.

[sutty]

No probs. Glad they got there safely.

Cheers

Sutty