Belt 6HV FBL conversion

[jperkosk]

So I want to get serious about changing over FBL TR700N to MB+CP2, the SK720 that sits on it will go on Compass 6HV, and the 6HV with all kinds of parts is taking the space up on the work table... That's the FB bird I bought from Gerd and I never really reassembled it waiting for FBL conversion parts to arrive. Change of priorities, then; to clear the work area I'll follow a new plan:

1. Reassemble 6HV converting it to FBL at the same time
2. Move SK720 from TR700N to 6HV
3. Install MB+CP2 on TR700N
4. Setup and maiden both birds

[jperkosk]

Following Ragge's advice I bought the 6HV conversion kit in the box here, it reuses FB head blade grips:



Got this really neat tool to grip the shafts, covers all sizes common in 450 to 700 helis:



Grips in the process of conversion:



Lubed the thrust bearings, assembled the head and dropped it into the frame. Had to assemble the boom, insert it in the boom box and thread the timing belt through the pulley, it has to be done at the same time the main gear is installed as the timing belt pulley is part of main gear assembly:



Tensioned the belt, installed boom supports, horizontal and vertical fins:



Vertical fin has a 3rd screw fixing it into the tailbox, interesting:



That's pretty much it, I think I'll connect a standard Rx to the swash and tail servos tomorrow to roughly set-up the head and tail before wiring up FBL controller. Everything below swashplate is Gerd's setup (he didn't remove servos arm for shipment, just popped the links off), above the swashplate everything is new, I wonder how close it's going to be:

[ragge1]

looking good

[Ah Clem]

Nicely done, sir!

[Grant_beltcp]

Looking good - I've flown that heli of yours before when Gerd had it certainly lively!

[jperkosk]

No worries, Grant, it'll be properly toned down by the time I'm done with it!

[jperkosk]

Connected temporarily AR8000 powered from 6VDC PS to cyclic servos and spent couple of hours playing with the head's mechanics. Had to adjust aileron and pitch links to get the swashplate level (I changed the washers on the servos to get the links as vertical as possible, not sure if it really helped) and I could get ±15° collective and ±10° cyclic pitch with relatively standard swashplate mix of A+60%/E-60%/P-60%, 0° with servos centered. Now it's time to unmix the Tx and mount proper FBL electronics (have to strip them from TR700N first).

Small setback: Futaba S9256 tail servo's dead. I powered it up from Aux2 channel set to center (0 on DX8 or new DX7s, 50% on old DX7), first from 5V power supply and the servo wouldn't move. Then I switched the PS to 6V and the servo moved a bit and just died. Well, that's a trip to LHS this afternoon, I'll check on my RC truck as well

[sutty]

Oh well, such is life, but yeah, might as well kill two birds. Is it meant to work on 6V that servo? Do you think you killed it, and it wasn't working to begin with because of something else, like frame rate, or centre pulse?

[DominicD]

Ok I have to ask, why is this in the Belt CP forum ?

[jperkosk]

It's a 4.8V servo, and I have AR8000 bound @22 ms frame rate, so any servo should respond to that, shouldn't it? Typically you don't kill 4.8V servo by applying 6V, you may shorten the life span. That's because when they rate the servo 4.8V they mean direct connection to 4 cell NiMH pack which may get close to 6V when fully charged.

Andy, thinking more of what you said maybe the servo isn't dead? Tried to find the specs on Futaba website, no luck.

Just got a brilliant idea and opened SK720 software, it's listed there as 333Hz 760us center pulse!!! So it wouldn't respond to standard 50Hz 1520us signal, would it? I opened it up, all connections look good, no burnt component smell, gears in perfect conditions. I guess I'll hold on with the proclamation of its demise until I have put it back together and tried it with SK720 first, it'll probably work just fine

[jperkosk]

Originally Posted by DominicD

Ok I have to ask, why is this in the Belt CP forum ?

Compass 6HV is a natural evolution path from Belt CP, I'm sure

[sutty]

Originally Posted by DominicD

Ok I have to ask, why is this in the Belt CP forum ?

See second paragraph in the linked post. Hopefully this explains it and will not cause an issue.

https://www.helifreak.com/showpost.p...67&postcount=2

In fact little in this forum has anything to do with the Belt anymore as there is little new to be said about it. We are simply former Belt owners happy to help out others when they visit, but in the meantime we have to chat about something.

Cheers

Sutty

[DominicD]

Normally I would have just moved the post, but I seem to remember you belt cp forum guys having some secret stone cutter society thingy going on and we leave you fellas be.

[redbird300]

Originally Posted by DominicD

Normally I would have just moved the post, but I seem to remember you belt cp forum guys having some secret stone cutter society thingy going on and we leave you fellas be.

That is greatly appreciated, and we promise we'll try to behave better in the future , but some buddies here are really hopeless.

[sutty]

lol, I love that episode. Thanks for your understanding. Thought you might be assigning the stone of shame to one of us. Good man.

Cheers

Sutty

[jperkosk]

Originally Posted by DominicD

Normally I would have just moved the post, but I seem to remember you belt cp forum guys having some secret stone cutter society thingy going on and we leave you fellas be.

That's pretty much correct
Although we still love our (mostly former) Belt CPs and are quite happy to help any poor soul who got conned into buying one...

Now, please refrain from hijacking this thread with irrelevant questions, I'm sure there is a world of Belt CP owners out there waiting for the 6HV FBL conversion info that could be applied later to their Belts, isn't there?

[DominicD]

Originally Posted by sutty

lol, I love that episode. Thanks for your understanding. Thought you might be assigning the stone of shame to one of us. Good man.

Cheers

Sutty

Stone of shame, no, stone of triumph, yes.

[ragge1]

I like this forum , nice place to get info , share some , get advice and good tips

[sutty]

Originally Posted by DominicD

Stone of shame, no, stone of triumph, yes.

lol, you are clearly are proper fan. I didn't think any of us deserved that.

Cheers

Sutty

[jperkosk]

Originally Posted by redbird300

That is greatly appreciated, and we promise we'll try to behave better in the future , but some buddies here are really hopeless.

I think I lost hope to behave better around Christmas 2010, but then regained a bit of it last Christmas when I got a voucher for a heli of MY CHOICE from Mrs under the tree !!!
It's a slow and painful process, though

Originally Posted by sutty

lol, you are clearly are proper fan. I didn't think any of us deserved that.

I didn't for sure but I think you did Andy. I declared an expensive servo dead and you thought of proper CPR for it .
So the saga continues; beginning to strip SK720 off my other Belt CP (TR700N) in a few minutes...