FBL Head setup

[terrybeb]

Or for a guy bringing you Timmie's.

[Cletus]

He, he, he
......well, I've ordered a couple prototype blanks Water-jet cut from 6061 aluminum stock, but the price so far is off the wall and not at all encouraging. Maybe a good excuse to get me a CNC Mill? (the wife's not buying that story either)
So, you all may have to settle for some Trinidad Rum ....not sure how much they will let me on the plane with.

[Cletus]

Finally got it to a pre-production prototype:

[terrybeb]

Very nice work!

[cbdane]

Originally Posted by Cletus

Finally got it to a pre-production prototype:

Looking forward to purchasing one of these bad boys!

[Cletus]

If only I could bring down the cost of machining the blank. These were Abrasive, Water-Jet cut from sheet aluminum.

[2SX1]

Originally Posted by cbergen

Not suggested to leave the servo's outside and turn the balls around, they just endup hitting the servo at extremes of throw.

I've tried it both ways now with the servo mounted inside and outside the frames.
Initially I built it with the servo mounted to the inside and collective pitch travel was virtually unlimited. I measured pitches in excess of +/- 15° which is excessive.
That servo was later found to be defective and was replaced.

Admittedly out of laziness, I mounted the replacement servo on the outside of the frames. Because the bellcrank will interfere with the servo as previously noted, It's possible to get a MAXIMUM of +/- 12.5°. Right now, 12.5° is plenty for me. If I decide I need more, the servo needs to be mounted inside the frame where the manual suggests.

I think having the servo outside the frame has both an advantage and a disadvantage. The disadvantage, we already know, is servo interference and limited pitch ranges.
The advantage is, linkage geometry is actually BETTER with the servo mounted on the outside.

Another disadvantage to mounting outside the frame, setup is a MUCH more tedious and time consuming process trying to get +/- 12.5°. So many things need to be just right to make it work. I must've spent 20-30 minutes getting it right.
Ironically, It probably would have been a 5 minute job start to finish had I just mounted the servo between the frames in the first place, but hindsight is 20/20.

[cbergen]

You'll have to show me a picture that you're geometry is better. I prefer the links to point slightly outboard at the triple bellcrank to prevent them hitting the servo wheel.

[2SX1]

It's hard to get a camera in there for a good well-lit picture. I'll try to do that for you tomorrow.
I assure you the the link does not rub on the servo wheel. There is enough clearance to slide a credit credit card through the gap.
I'm using the balls that came with the kit, the same screws, same double nut installation method as in the manual.
The geometry makes it so the pushrods are very close to parallel with the frames. I'd say within 1°

[cbergen]

I see. Parallel to the frames does not necessarily make for better geometry, but if you're happy with it, then so am I!