scx10 Chassis Mounted Servo CMS mod detailed write up

[xiteamxi]

Hoping a mod can make this a sticky
Hello well i was tinkering the other day after seeing they want about 50$! for a CMS kit and came up with this and figured id do a write up for you fellow scx10 guys and gals. All in all it should cost about 1$ and 10mins of your time.

Tools needed:

File
Drill press/drill
1/8 inch bit
Hex drivers/allen keys
Pliers/nut driver

Items need(see step 11 for a picture)
Stock steering parts
2 lock nuts
2 bolts
2 screws

1-So here we have a picture of your stock steering setup.

2-Remove your steering servo and servo mounting plate .

3-Unbolt your shocks,its also nice to put something under your skid to support it makes things easier.(just so happens i have a scale jack :lmao

4-Next remove your shock towers and set them aside.

5-Then remove your front cross member . You can normally pry the frame rails enough to get it out but if not you may have to remove your front bumper.

6-Now your chassis should look something like this. If you have the other cross member you will also have to remove it i removed mine a wile ago.

7-Next take your cross member and drill through the front driver side with a 1/8 inch bit so a bolt can slide through.

8-Well with your front cross member out take a file and file the in side as shown from were the brace that runs at an angle to the front you want this about 1/8 of an inch or until it sits flush when in the frame rails as shown.

9-Next take your driver side shock tower and file it as shown this is the side towards the front end.

10-You may now bolt your shock towers back on but don't put the front bolts in. You can also bolt your shocks on.

11-Now its time to pull out the stock steering stuff.
The black screws(top left)will be replaced with the gold ones(center)you just need a screw with a smaller head to clear the frame rails.
You will also need 2 bolts similar to the stainless ones(top right) they must have the tapered head and be about 1/2 inch long.
You will also need 2 lock nuts to go with the stainless bolts.

12-Next take the servo plate ,servo mounts,and new screws and put them together note leave the one screw some what loose

13-Now take your servo plate and tapered bolts(stainless ones i had in step 11) put the bolts through the servo plate and through your frame rail and tighten them down with the lock nuts.

14-Now you can tighten the other screw on the servo mount through the shock hoop. Also you can put the other screw in on the front passenger side shock mount (i left this out because i used a Allen key through this hole to tighten the other side to speed things up)

15-Bolt your servo up put some steering links on and enjoy your CMS for dam near free!!!!!

let me know what you think "thumbsup" or if you have any problems

 

[DJ1522]

love it! great work and awesome detail thank you!"thumbsup"

 

[northernerbill]

Nice job, does the steering link arm need to be altered in length?

Also what is the benefit of doing this, is it purely to create a more scale look or does it perform better?

Cheers Bill

 

[WIDELOAD]

Nice write up....Super easy to understand!"thumbsup"

Bill: You will most likely need a custom length drag link it all depends on the rig and suspension set up.
CMS itself pretty much for looks, it performs no better than axle mounted steering....It can actually be worse, because it moves the servo up higher, and without a panhard bar you will have bump-steer when the axle articulates.

 

[xiteamxi]

Nice job, does the steering link arm need to be altered in length?

Also what is the benefit of doing this, is it purely to create a more scale look or does it perform better?

Cheers Bill

Thanks guys ,and yes bill you will most likely need a custom length drag link and the cms is for a more scale look helps with flex some on these since the servo use to hit the frame and gets that servo up higher away from water."thumbsup"

 

[Perkolator]

good job "thumbsup" that's exactly how i did mine. why pay for a kit when the parts are already on the rig?

 

[Die-Laughing]

Hellz yeah!

 

[Meatwad]

How's the bump steer?

 

[Pau Hana]

Great info, spent the weekend trying to figure out a cms. Drove me nuts so my friend brazed sum tabs up with a panhard. I'll be taking this in for my next scale build. Thnx

 

[RCHuffer]

thanks for the post and write up...

 

[doors4u]

I mounted mine on a 1/8 piece of lexan because the stock servo mount was too low and it would contact the axle at full compression. Easy and cheap.

 

[OCMike]

Nice detailed write up w/pics thanks for taking the time to do and post up.....

 

[The-Blacksheep]

great mod thread will definately be playing with this one!

 

[xiteamxi]

Thanks guys i was running mine today all seemed good as far as bump steer ect beside the lack of steering power from the small servo i have one there when i put my jr9100hvt on that will go away.:lmao:

 

[rckjeep]

good job "thumbsup" that's exactly how i did mine. why pay for a kit when the parts are already on the rig?

Because the Hand bros KIT comes with a much higher quality servo mount that incorporates a panhard mount, it also mounts the servo up higher to clear the proper suspension geometry it also includes. Plus it has the axle mounted panhard/upper link mount, the upper link and all the hardware.

I ran it the way you have it but wanted to properly locate the axle using a 3 link so I made my own axle truss that had the upper link and panhard mount incorporated into it. The issue I ran into was the servo was too far back, too low and interfered with the panhard bar. I tried another truss with different geometry but still couldn't get it to work like a Hand bros kit.

I've done it successfully on a non SCX scaler but its just not worth the time it took when I can buy a kit.

I will say the OP did a great write up.

 

[xiteamxi]

for most people this way will work just as good as the hand bros. and for thos who have the extra 50 to throw around they will buy it any way but if your going to spend the cash doesn't hurt to try this way first."thumbsup"

 

[rckjeep]

for most people this way will work just as good as the hand bros. and for thos who have the extra 50 to throw around they will buy it any way but if your going to spend the cash doesn't hurt to try this way first."thumbsup"

I'll have to disagree with you on "will work just as good" but go for it. The real issue with your setup is when you try to run a panhard bar with the servo mounted there. Here's a little tip. While running a Y-link or 4 link suspension run high steer knuckles, it'll help flatten out your drag link angle which will reduce your bumpsteer. Happy crawling

 

[maxxa87]

Great idea but on my Honcho it didn't leave much for axle articulation. I'm going to make a plate like doors4u did to raise the servo up higher. I will also make a panhard mount, or try to atleast.

 

[hoghead5150]

my main question is can you still run the battery in the stock location after doing this? it seems that you have to remove the front crossmember that the battery tray bolts to. also it seems that the servo would not allow the stock battery tray to be reinstalled. is this the case?

 

[rckjeep]

my main question is can you still run the battery in the stock location after doing this? it seems that you have to remove the front crossmember that the battery tray bolts to. also it seems that the servo would not allow the stock battery tray to be reinstalled. is this the case?

It depends on what battery you are running. I'm running a Hand Bros. kit and notched the factory battery tray to fit around the servo. I'm only using one of the factory cross members. I used a TLT servo tower to hold it on the passenger side. Let me see if I can find a pic of my setup.

EDIT: I can't find any but I'll snap some.