scx10 servo not fitting

[teeforb]

what am i doing wrong. the servo horn is hitting the currie rod and no clearance from the chassis when suspension is pushed.

[Johnnysplits]

Maybe flip the servo horn 180* from where it is now.

[boohoo]

put the long rod underneath the knuckles instead of ontop or get a shorter servo arm

just noticed you have the rod screwed into the closet hole have you tried moving it to the furthest away holes on the knuckle

[teeforb]

Ok thanks! I'll try that

[TacoCrawler]

I shaved the the forward side of servo's plastic mounts down some.
Maybe about half the thickness (front to back)
This allowed the servo to shift rearward just enough.

I also used shorter button head screws to mount the servo.
If the horizontal screws are too long...
they will bottom out on the two vertical screws holding the servo tray
and won't be able to thread in far enough to secure the servo to the mounting blocks.

You could also shift the mounting plate rearward slightly..
But would entail drilling new holes and counter sinking those.

What wheel base do you have currently ?
Are the upper link rods longer then was original ?

Commonly longer (then original) upper link rods will rotate the axle housing forward some...
and push the servo forward causing interference with the cross member.

I'm purdy sure that when using the original link rods...
this interference does not occur.

I've seen some completely remove their forward cross member...
Though I think that will weaken the frame somewhat.

If removing that forward cross member....
I would advise to at least use a cross tube tied into the frame rails
to help box the frame at the front.

I realize there is an end cap that ties the two frame horns together...
But that is not enough boxing to the frame to maintain its strength.

Well... IMO anyways

edit:

I'm not familiar with that KO servo nor it's size dimensions...
But it looks like the front facia protrudes forward more then some others.
This difference might make the servo seem to sit farther forward.

you might want to look into that farther.

Is this KO servo a standard sized servo ?

[lemonhead]

move the tie rod to the forward holes on the nuckle

[Manning]

Originally Posted by lemonhead

move the tie rod to the forward holes on the nuckle

...and underneath.

[FastEddy]

The stock servo horn is thick. Issue with mone on the G6 build was the top of the horn was hitting the chassis not allowing any up and down movement in the suspension.
As mentioned above, I shaved mine down and it works fine.
I then went and got a metal horn and its works well also. Much thinner and more dependable then the plastic. No worries of it stripping at the spline.

[ZippoMan]

I was having issues with my set up too. I like the Axial clamping servo horns but they are very thick. I think with my set up the guy who built the SCX-10 Jeep used too long of custom lower suspension links and funky custom uppers. My servo horn would have hit the custom tie rod so I put round spacers and mounted it under the steering knuckles using the most forward holes. I noticed my drag link was not in a straight line to the steering knuckle when mounted on top of the forward hole so I mounted it in the back hole. Sure it may look different but it works. I was losing my mind trying to figure out why I had so many issues!!

I had the issues of the frame cross member hitting the servo horn. I solved that by making my front upper links about 1 or 2mm longer...tricky but it worked.

I was so used to my Wraiths where there is tons of room to mount and play around with servo horn combos and mounting positions.

I never had an SCX-10 based RC before so this is a new beast to challenge the mind. LOL

If I was to spend any more money to fix this right for my OCD, I would buy all new suspension links to correct the overall wheel base. I can't just cut the lower links because they are 1/4" SS custom bent.

Oh well the set up I have is working but may not look like everyone else's....lol

[ZippoMan]

Oh and I second the flipping of your servo! Look at the instructions. The horn works best when mounted like in the instructions.

[TacoCrawler]

Originally Posted by ZippoMan

I had the issues of the frame cross member hitting the servo horn. I solved that by making my front upper links about 1 or 2mm longer...tricky but it worked.

That's strange...
because adding length to the upper link rods
is usually what shifts the servo forward.

My Axial alloy clamping servo horn cleared fine until I added 2 mm spacers
to the upper link rods.

After adding those 2mm spacers to the upper link rods...
is what required me to move the servo rearward slightly.

After adding 8* Axial alloy C-hubs/knuckles...
I'm wanting to rotate the axle forward a little more
by adding maybe a total of 4 mm to those upper link spacers.
But in doing that...
will need to move my servo mount even farther rearward
to clear the forward cross member.

sooo... I haven't attempted that as of yet.

[6sharky9]

Originally Posted by TacoCrawler

That's strange...
because adding length to the upper link rods
is usually what shifts the servo forward.

My Axial alloy clamping servo horn cleared fine until I added 2 mm spacers
to the upper link rods.

After adding those 2mm spacers to the upper link rods...
is what required me to move the servo rearward slightly.

After adding 8* Axial alloy C-hubs/knuckles...
I'm wanting to rotate the axle forward a little more
by adding maybe a total of 4 mm to those upper link spacers.
But in doing that...
will need to move my servo mount even farther rearward
to clear the forward cross member.

sooo... I haven't attempted that as of yet.

I was counting on a pick so I could post one

"After adding 8* Axial alloy C-hubs/knuckles...
I'm wanting to rotate the axle forward a little more
by adding maybe a total of 4 mm to those upper link spacers.
But in doing that...
will need to move my servo mount even farther rearward
to clear the forward cross member."

you can move the cross member forward like I did

[TacoCrawler]

Originally Posted by 6sharky9

I was counting on a pick so I could post one

You usually post one anyways LoL

Originally Posted by 6sharky9

you can move the cross member forward like I did

true... or just omit that.
and add a single tube to span...

The boxing can occur between that spanned tubing...
and a solid forward mount at the frame horns.

As long as the forward side of the frame is boxed.
It should offer the strength needed up front.

Without boxing on the forward end of the frame...
a hard hit could fold the frame rails.

Yeah maybe no real issue at slow speeds...
But take a 20ft tumble down a rock pile...
and ya may find out the hard way.

[ZippoMan]

Okay so maybe I was wrong about why I changed the length of my uppers...oops. I did it so my drive shaft angle wasn't as sharp. Yeah I had a brain fart again.....lol.

I was able to move my cross slightly ahead but I can't eliminate it due to how my battery is located up front now.

Overall I am fine with my set up now. It is my gf's Jeep so it won't get much use in hardcore situations anyway. It may become an expensive shelf queen I hope not. :P

I still will say flip that servo over!!

[TacoCrawler]

My opinions of what should be done...
* random thought... so no real order here. Lol

Besides relocating the servo rearward some...

I'd probably pick another servo to use.
The forward facia profile on that KO servo looks to protrude
more then many others do. ( measured from the facia to mounting surface ear(s) )
I had a similar issue when moving from the oem Axial servo
to a futaba S3305. (Axial warranty replacement)
The S3305 had a taller facia profile then their oem servos
and required I move the servo farther rearward to alleviate
clearance issues at the forward cross member.

Move the primary steering link rod to the forward holes
at the steering knuckle arms.
Mounting them at the inner holes reduces steering throw
as well as causing more possible interference at the link rod and servo horn.

I can't say whether mounting the primary link rod under the knuckles
will offer any advantage.
But moving those link mounts to the outer holes
should help the link rod to clear the servo's horn better.

It does not matter much which position the servo sits (left or right)
with regards to drag link interference/bind.
But generally a shorter drag link length can bind more
then a longer drag link length might.

Spacing the drag link ends off the servo horn mounting might be helpful
in reducing bind as the servo arm moves (left/right).
* But too much... and the bind there could be worse.
^ This could be dependent of how far the servo is pushed rearward.

I use the shorter drag link currently (horn/DL on drivers side)
But I intend to run the drag link to the passenger side...
to see if that movement offers less bind at full steer (left/right).
One might even think to mount the drag link end to the inner surface
of the servo horn's arm.
Thing is... the farther the servo is mounted rearward...
the less likely the drag link could be mounted on the backside
of the servo's horn.

I believe that Axial installed the shock spacers on their shocks
because when compressed fully, the drag link would hit the frame.
I use 100mm CO's so they bottom out before the drag link
hits the frame rail.
So yeah... my suspension likely doesn't compress as much
as it might have when using the oem CO's without the spacers on the shafts.

and yeah, the suspension ride height would end up being taller (lifted slightly)...
But I have about 3/4" of static squat with my CO's (50/50 travel)...
so tho' my 100mm CO's do droop lower then originals...
the static ride height is actually less then oem.

So in closing and making it a short list..
the most critical things are...

Relocating the primary link rod to the outer holes of the knuckle's arms
and moving the servo rearward some on it's mounts.

^ that order

* test susp. function after each adjustment is made.
(Servo shift may not be required !?)

[Johnnysplits]

I still say flip the horn

[TacoCrawler]

Originally Posted by Johnnysplits

Maybe flip the servo horn 180* from where it is now.

Originally Posted by Johnnysplits

I still say flip the horn

you reiterate that...
but have yet to explain wutz that got to do with anything !?

'splain yerself

[stevetate12]

It looks like the steering knuckles are on the wrong sides....if you switched them side to side the mounting point would be way lower and nothing would be hitting


Sent from my PI39100 using Tapatalk

[stevetate12]

The knuckles are on the wrong sides....


Sent from my PI39100 using Tapatalk

[Johnnysplits]

Originally Posted by TacoCrawler

you reiterate that...
but have yet to explain wutz that got to do with anything !?

'splain yerself

Flip the horn 180*, attach the tie rod to the horn, add a 3 or 4mm spacer between where the tie rod attaches to the drag link, go in the Tx and reverse the steering. Done.