Verticle Mount Servo

crusader4x · #1 02-02-2003, 01:02 PM

Has anybody tried a vertical mounted servo w/ servo saver? I'm thinking about using this type of servo mount in my X4. I realize that on an X4 it'll be off center but b/c I'll be using an adjustable tie rod, it shouldn't be a problem.
The reason that I'm thinking about doing this is because I already use this setup on my Micro RS4.
Here's the basics, you mount the servo vertically w/ shoe goo, attach a small servo saver to your servo, then use small lengths of tie rod and rod ends to attach the servo to steering. It's basically the Team Epic style servo setup for the HPI Micro RS4.
I look forward to your responses!

gertman · #2 02-02-2003, 01:09 PM

Would the steering tie-rod be able to clear the center shaft and still have full range of motion??? I thought about a servo saver to BUT if u get a Hitech 81 there is no need, it's metal grear.

crusader4x · #3 02-02-2003, 01:15 PM

Quote:

Would the steering tie-rod be able to clear the center shaft and still have full range of motion???

Actually, that's part of my problem with the stock X4 setup. My servo is mounted on the right side w/ the current tie rod attached to the left side. This setup doesn't allow me full range of motion which is why I'm considering alternatives.

This can easily be done without a servo saver.

gertman · #4 02-02-2003, 01:18 PM

Why doesn't the stock setup allow you full range of motion? Have u tried turning the servo around AKA mounting it on its other side?

What brand and model number servo is this?? IT's sounds like it may be the wrong size.

crusader4x · #5 02-02-2003, 01:29 PM

I have an HS-81MG servo mounted on the right side with the servo "horn" side closer to the drive shaft.
My problem is that I have to severely reduce the right turn EPA or the servo is almost ripped off of it's servo tape.
I've also had problems when turning right, the diff just stops working altogether and I get a horrible "grinding" sound and the left wheel just stops turning.
Finally, if my servo isn't mounted "just right", when turning, the steering link tie rod will bump into the servo horn causing additional probs!
Sounds like you're the resident DTM expert, thanks!

crusader4x · #6 02-02-2003, 01:35 PM

Actually, I "think" thats how my servo is set. W/ the horn nearest the center drive shaft.
I don't have my car in front of me.

gertman · #7 02-02-2003, 01:47 PM

Somthing sounds a misss.... I have mounted by servo with the horn on the right and left with out any trouble.

Wait a second, did you say "rip off your servo tape"?? Well, that's the 1st problem. U need to shoo goo the sucker in place and leave it a good 12 hrs, try to clamp it after glueing.

Quote:

I've also had problems when turning right, the diff just stops working altogether and I get a horrible "grinding" sound and the left wheel just stops turning.

This sounds like u may have a spacer installed incorrectly in or around the front diff. OR, you need to shorten the adjustable front shaft of the diff.

Quote:

Finally, if my servo isn't mounted "just right", when turning, the steering link tie rod will bump into the servo horn causing additional probs!

I think maybe because yoyu are using servo tape to mount your servo, it raises the servo up just enough that you have the problem described above.

Well, hope I have helped some......I can always post some close up pics of my servo installation if needed. But give me a couple of days.

crusader4x · #8 02-03-2003, 03:28 AM

I found sources of most of my problems.
First off, the servo horn I was using was too short. When I turned to the far right, the linkage was rubbing against the drive shaft spur gear. I picked a longer servo horn and used the "outermost" hole. No probs in that area any more.
Secondly, I noticed that the toe-in/toe-out linkage was also rubbing against the drive shaft spur gear. I got out my hobby knife and cut away the ball ends where they were rubbing the gear.
I also took your advise and shoe gooed the servo to the chassis. That's working out well now.
Now I have a new problem, my X4 seems to make a tighter left turn and wide right turns. I've adjusted the EPA and when I eyeball the end points of the turns, they both look about the same. Is this a diff problem? Should I loosen?

gertman · #9 02-03-2003, 04:47 PM

Really, yours diffs are not adjustable. So unless you some how managed to adjust them and make them tight, than yes, I would suggest loosening them.

To adjust your EPA (end-point-adjustment) use the distance between the tire and trailing edge of the front bumper (chassis).

crusader4x · #10 02-03-2003, 11:31 PM

Quote:

To adjust your EPA (end-point-adjustment) use the distance between the tire and trailing edge of the front bumper (chassis).

That's exactly how I adjusted the EPA on my car BUT it still makes tighter left turns and wider right turns.
Any suggestions? Do you experience this as well?

gertman · #11 02-04-2003, 04:55 PM

Something still seems a-miss...

Check your toe-in link. Maybe your front wheels are not centered.

Make sure, with your car on the ground, that the front wheels turn practiclly the same amount left and right.

Maybe.....one of your front foams is smaller than the other? Try changing them; what about the rear?