Swash not level

[Planehazza]

Hey all,

I have my bellcranks set at midstick (driver through) so they're all perfectly straight etc. With the premade links on, the swash tips back very slightly. The two links from the front servos ar about 1.5mm too long. How can I adjust these? Turning the plastic links as on normal rods isn't working as they're premade and non adjustable. It's only a very slight tip, so should I leave it as is, or electronically trim the swash using the FBL controller?

[Surinder Singh]

Hey all,

I have my bellcranks set at midstick (driver through) so they're all perfectly straight etc. With the premade links on, the swash tips back very slightly. The two links from the front servos ar about 1.5mm too long. How can I adjust these? Turning the plastic links as on normal rods isn't working as they're premade and non adjustable. It's only a very slight tip, so should I leave it as is, or electronically trim the swash using the FBL controller?

I had a similar problem with the so called fixed length links. One of them was 1.5mm too long. I also realised that these were not adjustable. While I could force it on the servo was screaming to be let free. So I built with only one link on the bell crank. What Noel Cross did when he helped me with my set up was to put a slight bend in the long link that shortened the overall length of the link. This was just a temporary fix in order to get both links on and to do a test flight. I replaced the link with a conventional adjustable link of the correct length after this first flight. Was a cheap fix but someone in the QC dept at TT responsible for the length of these fixed lenght links was a little slack when my links where born

[Surinder Singh]

Forgot to mention that all the fixed lenght links in my kit were anodised or sprayed black. The replacement link I made up myself was silver as I couldn't find one in black. I went over the exposed metal part of the link with a black permanent marker. Now if you look at it you'd never be able to tell the difference between the stock TT fixed length links.

Surinder.

[Planehazza]

Forgot to mention that all the fixed lenght links in my kit were anodised or sprayed black. The replacement link I made up myself was silver as I couldn't find one in black. I went over the exposed metal part of the link with a black permanent marker. Now if you look at it you'd never be able to tell the difference between the stock TT fixed length links.

Surinder.

Thanks mate. Making my own was the first thing I thought of, but these are larger ball links and I don't have any. Like I said, it was only fractionally off and probably wouldn't matter in flight. To compensate, I've just cheated and used 10% down sub trim on the front servos, and 10% up on the rear.

[Surinder Singh]

My problem was that only one link was the wrong length so putting a single link on was fine but when trying to put the second link on my servo was screaming as both lengths needed to be the same connecting to the TT servo horn, so I couldn't use sub trim in my case. But if sub trim is doing the trick that should be okay depending on your FBL system.

[Planehazza]

My problem was that only one link was the wrong length so putting a single link on was fine but when trying to put the second link on my servo was screaming as both lengths needed to be the same connecting to the TT servo horn, so I couldn't use sub trim in my case. But if sub trim is doing the trick that should be okay depending on your FBL system.

Yeah it's the servo trim feature of the FBL unit itself, not on the Tx so I'm good to go Just got to tackle the uneven pitch range now. For some reason, with swash level, I'm getting +12 and -15 degrees.

[Surinder Singh]

Yeah it's the servo trim feature of the FBL unit itself, not on the Tx so I'm good to go Just got to tackle the uneven pitch range now. For some reason, with swash level, I'm getting +12 and -15 degrees.

Sunny Manku had the same uneven pitch range on his TT700E. I think he just skimmed off some of the excess pitch in the tx with his pitch curves. I've done that a few times myself on the vbar and other FBL units seems to work just fine.

As the links are fixed length and zero pitch and level swash is set up by inserting the driver into the slots I can't think of any other way of rectifying this.

[Planehazza]

Sunny Manku had the same uneven pitch range on his TT700E. I think he just skimmed off some of the excess pitch in the tx with his pitch curves. I've done that a few times myself on the vbar and other FBL units seems to work just fine.

As the links are fixed length and zero pitch and level swash is set up by inserting the driver into the slots I can't think of any other way of rectifying this.

I haven't got space in the house atm to properly set up the model on a bench and check. Certainly be eye it appears to be 0 pitch at midstick, but if it's not that could account for the skewed ranges. I'll check tomorrow

Thanks!

[pgkevet]

I don't know how these links are made up and whether this fix might work but possibly you could cut a section out of the middle of the link then sleeve over any rod section with a rigid tube with slow epoxy.. set up the model and pack the swash dead level while the epoxy sets-up for perfection?
Any local model shop or even B&Q should keep thin brass tube or other about.

A quick thought... are you sure the frame is fully square?

[Guest]

Vbar uneven pitch deal with by adjusting your travel limit in the tx. It's the only channel where you would do this.

MJ