Steering fix that works

[TypeZer0]

Ok, about a month ago a member of the other forum named gvitya found a steering fix that involved changing two resistors with 4.7kOhm ones. He has the picture showing which resistors to change here. (Picture belongs to gvitya)

Well, I just received a small number of 4.7kOhm surface mount resistors and i immediately tried the mod. Ran into a problem....the resistor I bought was like twice the size of the ones RS used. No biggie, rather than solder the very ends of each resistor to the solder pad, I simply covered up both solder pads with the resistor soldered on. My second problem was the resistor on the right in that picture I linked to had a very small surface mount capacitor next to it which i accidently knocked loose so be careful when working on that one. took me 15 minutes just to put that one back on because it was so small and i dropped it on my carpet

Well, it's all done now and let me tell you, my original turning radius at low speed on carpet using AWD was about 18 to 24 inches (rough estimate) and it is now 12 to 18 inches (rough estimate). i've been able to get an 8 inch turn radius on a medium speed without the rear end coming out and wihtout flipping it. I also noticed that with my 6 cells, the steering used to give a chatter that went away when I lightly tapped the front wheels. I have yet to see the chatter after this mod.

There is a slight issue when using AWD, when turned to the max, the joints get very close to binding and would actually slow down. I had to dial the steering range down a tiny bit. This would be a problem in the long run due to the stress you would put on it turning it that far but just dial down the steerign a tiny bit and you're all set.

I just like to thank gvitya for this mod.

[neurokinetik]

Well, I know what I'm doing now when I get home. :lol:

[backtrack9]

Originally posted by neurokinetik
Well, I know what I'm doing now when I get home. :lol:

Hey Neuro, I thought I would give you a piece of insight as to the exact surface mount resistor I used. Here is where I got mine from http://dkc3.digikey.com/pdf/T041/0860-0864.pdf. I used the 0603 Series 1% resistors (part# 311-4.7k-HCT-ND). This mod really makes a huge difference. I hope this helps.

[TypeZer0]

or you could use 5k ohm pot's, the kinds with like 15 or more turns so you can fine tune the range

[Kubrel]

So do they give it increased range or do they make it steer more????

[TypeZer0]

if you notice how if you keep the steering turned all the way, it really isn't turned all the way as far as it can physically go. just look at how far it can turn using the remote, then turn it off and see how far you can steer the wheels with your fingers. notice how there's still a bit of room left? well, i think this little room was left intentionally so that the AWD won't bind and cause slowdowns and stress the joints. i noticed that after doing this mod, to adjust the steering range on the remote so that it won't bind the awd, i'm pretty much back to how far the steering would go stock-wise. that's why i took out my AWD so i could have it turn physically farther and thus reducing my turn radius by a LOT. try it and see for yourself. it turns so sharp that on carpet it flips going at medium to high speed

[Kubrel]

So do you actually have to remove the old peices and install new ones or do you piggy back them? I do not have the awd mod. I am trying to set up each car a little different so i don't have to keep changing stuff. I have a everyday mod an expiriment mod and i haven't named the third yet. I want to keep at least one bone stock for just messing around and chasing the cats.

[TypeZer0]

you gotta remove the old ones first. piggybacking them will produce an equivilant resistor with a value below either one of the resistor (inverse sum of inverses)

[dIsEaSe]

What's the difference between this mod and putting resistors before the servo?

[LBRC]

About 550 ohms. That is if you use 3.3K resistors for the inline steering mod.

Really very little since essentially it’s the same mod, by adding two 3.3K resistors to each side of the servo wires you are putting them in series with R26 and R27 on the circuit board for a total of 4.4K ohms. The 4.7K surface mount mod has looks better and is easier on the steering servo wires with just slightly tighter steering compared to the inline mod which easier for some people to install and uses resistors that are easier to find.

This is the first thing I do to each and every Xmod I get my hands on. With this mod my Xmods have a turning radius that is indistinguishable to my Mini-Z’s, roughly an 18 inch circle.

I find replacing the resisters on the circuit board easier and faster, but I also have a lot of soldering experience and a surface mount rework soldering station. Ethier way it is a must do. Props again to gavitya if it wasn’t for this mod I’m not even sure I’d like Xmods.

P.S.
Be careful when ordering this mod off of eBay or obscure web sites, there are people selling it who apparently don’t know what a 4.7K 603 package surface mount resistor should look like, it should have a 472 on top (it stands for 47 and two zero’s). I have heard of and seen people who got everything from 470 ohm to 47 meg, it’s amazing what some people will do for a few bucks. And if you’re going to do the inline mod use 1/8 watt resistors not the honking big ¼ watt ones from radio shack, go to an electronic supply store.

[HammerZ]

Where would be a good place to get those board mount resistors? Think the shop here will look into getting some? If I can get them from here I may get some fets while I'm at it. Some electronics supply places you have to buy at least 50 of these and they cost around $2 and the handling is $5 itself.

[rssjib]

Those things are hard to solder on. They are too damn small!

[HammerZ]

I've done PCB repair work before, so I know how tiny these things are.

[LBRC]

If you can't find any send me a self addressed envelope and a buck and I'll send you a couple of each type.

[HammerZ]

Thanks, I may have to get hold of you on that.