Options for Trex 600 CF FBL conversion

[007brendan]

I have one of the older Trex 600 CF helis. I'd like to convert it to flybarless. It looks like the only heads still being sold are the DFC heads, so that's probably the route I'm going to take, but I'm open to other options.

Based on some other posts and pictures, it seems like I should just be able to use the DFC conversion kit, along with a newer set of blade grips and feathering shaft. Is that right?

I've seen a couple of posts where people mention the DFC main shaft being too short, and the stock main shaft being too long. I don't want to have to cut down the stock main shaft. I've read one post where someone claimed to have used the 600 Nitro shaft with success. Is that true?

• DFC conversion kit - http://www.helidirect.com/align-t-re...ed-p-26156.hdx
• Blade grips - http://www.helidirect.com/align-meta...ro-p-23818.hdx
• Feathering Shaft - http://www.helidirect.com/align-feat...00n-p-1543.hdx
• Trex 600N Main Shaft - http://www.helidirect.com/align-600n...et-p-29945.hdx[

[nightflyr]

These are still available...

RJX through HobbyKing

[strat1960s]

I did a 600E CF to DFC head conversion a few years ago. I'm checking my notes to see if my part numbers are correct. Worse case, I pull the shaft out and post the length and diameter to you. I did not have to do any cutting and grinding to get the shaft to work. I did work closely with Ron at heliproz. Great guy and he knows his stuff. I'm sure he'd be glad to help you out with any questions.

Ted

[strat1960s]

Total Length of the shaft: 7.5 inches / 190.5mm (+/- .5)

http://www.ronlund.com/rcheli-prod/HN6118.html comes out to 191.8 mm which is probably the right size.

Hope this helps.

Ted

[ticedoff8]

Strat1960s: Thanks for the pictures, that helps clarify your comments in the other post on this subject.
You have the old style 600E that uses the swash anti-torque guide.

The newer 600E use a fixed length A-arm on the elevator link that doubles as the swash anti-torque guide.

The 191mm mast is too tall to give you the "benefits" of the DFC head - it is about 10mm too tall.
You may have your own thoughts on the "benefits" of the DFC head. It is a subject that has been debated for awhile. Typically though, the main benefits talked about are moving the head closer to the frame for mass-centralization (faster roll & flip rates) and lower drag.

You can make it all fit together on the older 600E frame by raising 191mm main mast and moving the swash up about 10mm.
But it is still too tall to get the "benefits".

If you want all the "benefits" of the DFC head, you need to keep all the DFC dimensions.

If 007brendan has the older 600E frame he can do what you did and get a DFC head on the 191mm main mast and it will "look" like a DFC heli. but, it will not preform like a DFC heli unless he can cut down and redrill the 191mm mast to the DFC height.

Personally, I would not sweat the 3rd bearing block. Use the stock, off the shelf, 600E DFC main mast and be done with it. It does not reach the 3rd bearing block
But (keep in mind), KDE and Lynx have not addressed it with a longer 600E DFC shaft or conversion.
I have to assume no one is really having a problem with it.

[SumOFparts]

Here's irony - the latest conversion kit from align converts the dfc back to a EFL -
comes with everything - but the swash and grips and bearings -

And to boot - cant use the dfc swash with this - you got to have one of the older fashion swashes that came on the original 550/600e's - cause the new head has follower links.....


http://www.ebay.com/itm/Align-Trex-5...item2a4653e1a4


You'd also need grips and bearings - bearings can be had from your original 600e head- maybe feather shaft too -
the new grips needed tho -

http://www.ebay.com/itm/Align-Trex-6...item2a445a08cd

[SumOFparts]

Or you could find one of the 600/550 efl main rotor sets complete off the V1/V2's -

the going price on ebay and forums is about $75 for the EFL's (550G's V1/V2) and about $90 for the DFC ones - just have watch for em.
bought several at that price - and that's usually with swash and main shaft (177mm).

You could even place an add in the the 'stuff wanted' thread.....there are bunch of them around.

I could find 3 different shafts for 600's - shortest to the longest - longest being the original flybared 600 - 172/192/201 mm respectfully - dfc/efl/flybarred

http://www.helidirect.com/align-600d...47-p-26775.hdx
http://www.helidirect.com/align-600f...ss-p-20925.hdx
http://www.helidirect.com/align-main...00n-p-7081.hdx

The other one you found is specified for nitro dfc only - looks to be the one that uses 3rd bearing block - 179mm - the pic up top is correct - the detail pic lower is in error - check the bottom hole position....

http://www.helidirect.com/align-600n...et-p-29945.hdx

[Luvmyhelis]

Originally Posted by ticedoff8

Personally, I would not sweat the 3rd bearing block. Use the stock, off the shelf, 600E DFC main mast and be done with it. It does not reach the 3rd bearing block
But (keep in mind), KDE and Lynx have not addressed it with a longer 600E DFC shaft or conversion.
I have to assume no one is really having a problem with it.

Depends. With the gen 3 Kde 700 505 or my Scorp 4525 ult. I run on 12s. Without the lower bearing support I just rip through gears. With the support, the heli is twice as quiet and I can't seem to kill my Kde mod 1 gear. It all depends on what you intend doing with the heli. Even the mild sport guys with highly modded older Esp's that I fly with have the lower bearing in place due to the noise the two bearing version produced. Both run Sk720s, and their rotating assembly vibes dropped by almost 80% by doing the mod. Cheapest shaft out there is the one HK sells for under $4. Two run Rjx heads, I run the Compass. All of us run direct servo to swash mods.

[1340]

strat1960s
I noticed you kept the bellcranks. Are the bellcrank to swashplate links standard
length?
Also, other discussions seem to suggest adjusting the travel when retaining bellcranks. Did you adjust the travel?
Any further info would be appreciated.
Thanks.

[strat1960s]

It's been 3 years since I converted the 600 CF to the DFC head. I don't recall everything I did to get it to fly.
I measured the connecting rod from the bell crank to the swash and came up with 67.89mm+/-. As far as travel adjustments, like Ticedoff8 noted, going with the longer main shaft defeated one of the purposes of the DFC head, which was to bring the head closer to the body. I do not recall getting too technical with the conversion. I used the AR7200BX. During the BeastX setup, I made whatever adjustments to the connecting rods to get within specifications.
Now that I'm looking at the heli, I probably could have ditched the bell cranks and gone straight from the servo(s) to the swash.
The process, like I said, wasn't overly technical. I just made sure the swash was where it needed to be, level when it was supposed to be level and gave the +12/-12 pitch. The hardest part was learning how the length of the main shaft affected the swash and blade pitch. Once I figured that out, it was fairly easy.
Ted

[Trexwilly]

I converted mine years ago, the geometry is not to ideal, it is doable, I use a VBar, and the numbers are way off from what the wizard says, but it still flies OK!