What are the advantages and disadvantages of the pull-pull system on the elevator of a 1/4 scale? Seems to make sense to have a pull pull system if the model comes out tail heavy.

Hi,
Look at the pattern forum as some of their models use this system. Personaly i'd rather a pushrod as wires seem to go slack too easily for me....jmo though!...having said that my Dads 1/4 tiger moth has run this system for years and has had no problems...what type of model is it for?

happy flying
rich

It is for a SIG 300xs. I am trying to keep it from being too tail heavy and thought that moving the two elevator servos from the tail back into the fuse would help a lot in moving the cg forward.

In my opinion after going with pull/pull elv. on my DP330 I would never go back again to pushrods.The plane with pull pull is alot more crisp and responsive & if you do it right & use thread lock on your clevis locknuts & tighten realll good it will never get slack on ya.I am running mine with a JR8411 and it is 1 hell of a awesome combo.Between that and the JR 188 ouncer I have on the rudder @.08 seconds & the quick 155 oz .15's on the ailerons I have a 3d demon on my hands now and she does snaps/rolls so fast -I am gonna be loving it..Flew it the 1st flight last sunday & totally loved the plane .So anyways you can't go wrong with pull/pull on the elevator besides its cleaner too,no unsightly servo cutouts in the tail



Steve

Iad pull/pull elevator in a 1/4 scale Pitts for 2 seasons. Sistem was reliable and trouble-free.

Hi,
Cool, what are you guys using for wire, mine seem to go slack every so often.
Cheers
Rich

I've used it for many years....rudders and elevators on airplanes up to 25%'ers, although my current planes were built stock per manf, so they have pushrods.

I've found the best value on stuff to be 45lb or greater stranded stainless steel, nylon coated fishing leader line with crimps. Any good fishing supply house will have this stuff...it's cheap...

Although not "trick" enough for most folks, I use Sullivan 4-40 eye bolts, lock nuts, threaded into the Nelson (old Rocket City) fittings that I get from John at Aeroprotect RC.

Using the eyebolts means you can replace cables if they wear, without messing with the control arm/clevis...SUPER easy to set up.

Hi,
I just gotta ask about your Avitar. It that a cat in your airplane? If so, is it still alive?

While I was building the Wildhare Giles, I left the fuse on the bench overnight...when I went out in the morning, there she was, perched and snoozing in the open hatch (I hadn't installed the canopy yet)....I just had to snap a photo...too cute.

In case you're curious - she is a VERY small persian; the Giles isn't THAT big

She stays in the house....not to worry...

Can anybody post pics of pull pull om split elevators?

The MK bellcrank system with one servo could be another option to 2 servos in the tail.
Scou

Like aerobob says, coated fishing leader line makes very good pull-pull cables. When you crimp 'em make sure you pass the wire through the crimp sleeve twice to eliminate the possibility of the cable somehow pulling free. For a cleaner install I slip a piece of heat shrink over the wire and after crimping the connection I shrink the heat shrink over the connection to make for a cleaner looking install.

Oh yeah, never use nylon clevises with those little eyelet rods (4-40 or 10-28) to attach your wires to control horns or servos. I learned that one the hard way.[:@]