I just finished installing a tailwheel retract to my Kyosho P-40 50size and have a question.
for the steering of the tailwheel, can I use the rudder servo to also move the tailwheel?
ie: both p-rods to one servo. thanks for your time.<! / message ><! attachments >

Simple answer, ABSOLUTELY. Idid the same thing on my TF .60 P-47D. I hooked it up with a set of cables on apull-pull set upthat were on the rudder servo with cable that allow the gear to retract unhindered. I would love to show you some pictures, but Ido not have any and the airplane is not even in the same county right now.

pics would have been awesome but no worries.. thank you very much Sir.

your not going to be able to do a pull/pull with that unit since it looks to have only one side for stearing(tiller style) the PP needs flexable wire leaders to bend when retracted.

if you were going fixed then a ball link in the pushrod would work just fine here is a basic example of my modified Hangar-9 Mustangs TW set up, the servo is mounted in the tail but the set up is the same.

you might want to invest in one of the Robart 121 units http://www3.towerhobbies.com/cgi-bin...?&I=LXET15&P=0 there plastic as well but have a yoke (2 sided) stearing set up, here is a example of how I configured mine using plastic coated fishing leader,single servo stearing,and rudder, air retraction.

might give you some ideas

P40K,

May I ask who makes that tailwhell unit? It looks pretty good and light weight - good for some small models I have.

Although that set up is a push-pull tiller arm, it looks like the tiller is installed with a set screw...does it come apart? Think you could source, modify or make a two sided servo arm with a set screw and switch it out?...pull pull with light cables that attach rearward to the rudder would be light weight, simple and probably work better, given the direction the tailwheel retracts. A couple of small guide tubes will help keep things from getting tangled.

Just some thoughts.
Rick

taf,
the tailwheel retract is a Robart 122.. this one barely fits into my 1:8 scale P-40. as far as it coming
apart, its staked everywhere. the setscrew that you see is to adjust the up/down length of the steering
arm. suffice to say, noway a dual steering arm will work.

bigtim,
thanks for the pics! but the Robarts 121 will not fit (its for 60sized+ aircraft).. period, unless you want to move the tailwheel way,
way, way foward. sooo looks like its going to be the push/pull for me.

I appreciate all the input guys!

Make yourself a double tiller arm so you can use a pull pull system if you can still get into the fuse to run the cables. My rudder and TW are on the same servo in my Z P-40.

Barry
www.canopyrailsforwarbirds.com

Ok guys, looks like I can do the pull/pull system. I cut off most of the steering link from one side,
and now I'm going to epoxy another steering arm on the otherside. I also have to 10" lengths of
hard plastic tubing for guides. is that enough? also, are you guys taking about steel cable? string?
20lb fishing line going to the rudder servo? sorry if that sounds dumb. never made one of these
things before. any/all help appreciated.

If you use mono fishing line it'll stretch. So you don't want that.. Use either steel/brass cable (availabe in the LHS) or kevlar string. That is also sometimes availablle in the LHS.

Hmmm a valiant atempt, but it will fail, i see the arm you have cut away, you plan to glue an arm on the other side? is that correct? not a hope, the glue area is too small, and that plastic is difficult to glue at the best of times,if thewire leg is secured into the body, and will pull out, better to find a mate with a lathe, and have him make a double sided arm for you, with a boss that is drilled and tapped for a short grub screw (the type with no head, just a hex hole for an allen wrench) this can also be brazed or soldered up out of sheet steel, and a metal wheel collar,

"Hmmm a valiant atempt, but it will fail"

way ahead of you. I have a game plan.. without failiors. but on a side note, epoxy,
with the right surface prep, can be just as stong/stronger the a soldered joint.

Hi buddy,Oh yes you can use the same servo for the ruder and tail wheel,the only thing you need it it`s astrong servo:

these is my installatation

thanks for the pic kurrikan. I see the vast majority are using cable. I have some 40" steel leaders
that should be ok. the problem I'm having is a lack of room on the tail end lol. its begining to hurt
my brain.

Looking at your rudder linkage, I'm wondering why they didnt exit the rudder push rod on the other side of the fuse??? That way you wouldn't need that goofy bend in push rod. It would also give you better clearance for your tail wheel.

the one with the goofy bend is the 2nd elevator pushrod that I added awhile ago. the rudder/elevator
pushrods sit about 3/4" below the retracted tailwheel.

i wish you well with it, but i do this for a living, it needs a very simple tiller arm making, then you wont have to do it again

you have an example for a 1:8 scale WarBird thats installed?

the photos I provided are of a 1/7 FW190 its very close in size to the Kyosho P-40. was there a reason for using the double pushrod set up for the elevator at 1/8 scale its really not necessary, a single pushrod would work fine, with a wire joiner, between the 2 elevator halfs.

for the stearing arm if you insist on using the smaller reract ,if you cut the arm out of brass sheeting(obviously doesn't need to be that big) and solder it to a small wheel collar it will work just fine.

you get more bite out of the solder if you grind the chrome off of the side of the collar,solder the arm to the collar and drill the hole out, then simply slide it onto the wire and its done,good luck with the epoxy.

as for the PP wire I use 30lb plastic coated fishing leader and lead crimps to connect them to the control horn, they won't come off, there quite strong.

there are several ways to make the wire connections to the servo solder threaded brass couplers to the ends of the wire then use a plastic or metal link. or like I did in the photos, use EZ conectors they make for quick adjustments,a little blue lock tite sets the screws in place.

heres another example of another installation with the EZ connectors at the control horn it makes for a more difficult adjustment to tighten the PP cables,I used threaded couplers and ball links to attach to the servo.

not my first tea party

YOU are my hero Sir! thats exactly what I needed to look at. at least I have a clearer
idea on what to do with my first tea party. thank you again very much.