Suspension Tweaks need your help.

[solomon7]

1 cm.

[Duuuuuuuude]

Originally Posted by solomon7

1 cm.

I was going to suggest 10mm, but that works too.

[opek]

Originally Posted by CruisinMT

I need to add weight as well to make the suspension really work and achieve full spring compression.

Or you could use softer springs!

[solomon7]

Ditto on opek's post.....
If ya don't want to get springs, and want to work with what you've got, take the ones you have n heat them till they are red.
Even oven heat will help if no torch, use the top element.
It'll soften them quite a bit. I liked my reheated springs fwiw.

YOu could also snip off one ring at a time till they are to your liking. Cut toff too much?? Preload spacers'll fix it.

Worse case scenario, you have to get softer new springs that you already wanted, but at least you tried

[CruisinMT]

Originally Posted by Duuuuuuuude

I was going to suggest 10mm, but that works too.

Snoogens. I'll give all the suggestions a try.

[CruisinMT]

I cut apart a homemade split pack since I'm using Lipos now and put two on each side of the front axle and 2 in the back hanging off of the servo plate. It flexes way better and I almost get the full range of the shocks now. I also added 10mm fuel line inside of my shocks to lower it. It's drags on rock now where it wouldn't before but it side hills like a beast and as long as I pick the right line it seems pretty much unstoppable even with wet and snowy rocks. I can't wait to take it to an old rock quarry a couple miles away. It should be awesome. I do have some axle steer which sucks, and I'm not sure how to eliminate or at least minimize it. Help would be awesome. Thanks again guys. Here's some photos.

[opek]

Roll axis will determine your axle steer. Search thread titles for "anti squat diagram" and wade through it. There is discussion of roll axis and how to calculate it. A flat roll axis means no axle steer.

[CruisinMT]

Ok well since dropping my ride height I now need to take out a spacer on my rear upper links where they connect to the rear plate.. Presently instead of being parallel to the ground they are angled down toward the middle of the chassis. Oh and by the way the TT is totally gone as of now. Just that darn axle steer going on. I'm running 35wt shock oil all around, is that too heavy?

[opek]

If you search thread titles for "anti squat diagram" and wade through it you will find a discussion of roll axis and how to calculate it. You can even search for the thread then once you are on page one you can use the "search this thread option" just above the first post. Type in roll axis and read.

I understand it's a pain in the ass, and my first post above is in some way a dry satire. I can feel there are good FAQs coming in the future.

[ERV JR]

do you shocks leak ? mine do and are a mess now

[solomon7]

Spreading your lowers on the axle as wide as possible helps a ton with axle steer. You'll need 30mm bolts to have enough to put the lowers on the outside of the axle bracket.

Seems a good all around scheme seems to be lots of triangulation for the lowers and hardly any triangulation for the UPPERS.

Read those threads oped mentioned and reread them. It seems complicated at first but it slowly sinks in.
Diagram for Anti-squat

One of the originals, Pretty techy, but it sinks in:
Anti Squat and Suspension Tech

What helped me was knowing how my rig handled already, taking a pic of it, and using GIMP to lay down the lines once I figured my CG.
Started movin my uppers around and plotted the Squat values. on GIMP.
Then added or remove Antisquat with the uppers or ride height, short drive and note changes.
After a few variations the numbers make total sense, I have a real good idea of what's going on with my rig's geometry. Already see design changes that need to be made for the ride height variation I want..

[opek]

Originally Posted by solomon7

Seems a good all around scheme seems to be lots of triangulation for the lowers and hardly any triangulation for the uppers.

FTFY. Can anyone can comment on why?

[solomon7]

Thanks opek, slipped past my proofread lol.
I could go in to roll centers and axis', but I"m only 80% there in fully understanding those principles, so to avoid tasting my own foot too much, I'll use a simple example:

Hold your arms straight out in front of you.
They are basically Lower links.
No move one arm up or down to 45*while viewing your profile in a mirror.
You'll notice the moved arm is now 8-10 inches "behind" the stationary arm.
You "axle" is steering.

Now hold your arms straight ahead, but spread horizontally at 45*.
Lower or raise 1 arm to 45*still viewing from a 90.
YOu'll notice the moved arm is now only an inch or 2 "behind" the stationary arm.
Less axle steer.

Make sense??

As far as Uppers,straightening them extends their point of convergence behind the rig,or their Instant Center.
YOu should also Find the lower links Instant Center from their point of convergence

For the Upper's Roll Center if you follow from their Instant center back to the rig at the lower links slightly upward angle (unless your lowers are flat lol) Youll notice when the line goes over the rear axle to it will be above the upper links. Where it's above the axle centerline is that axle's Roll Center.
Your Axle's Roll Axis is a straight line drawn through both Roll Centers.
This is what really matters when we're talking TT, binding under load and the like.
Each axle technically has a Roll Center and a Roll Axis.
The axle's Roll Center is more important when tuning one end or the other, but to tune both axles together you draw a straight line through the front and rear axle's Roll Centers. This is the RIG's Roll Axis.

With a 3 link, since both uppers converge right at the axle, their IC is already over the axle, so that's the Roll Center on a 3 link. Not very high at all and almost "in front " of the axle. Crap.

With less triangulation of the uppers this pushes their IC way back so when followed back to the rig's axle the Roll Center is much higher.
This will effect from which point the suspension Rolls around. Will also effect Where the torque tries to twist" or leverage.
Low roll centers will put more rotational leverage to the chassis. High RC puts more to the axles hence less body roll under load and more predictable suspension..

From my understanding if your front's RC is slightly lower than your rear's RC this will make the rig's Roll Axis slightly downward sloping. Seems to be a desirable trait in a crawler for climbs since the front flexes "closer" to the sprung weight than the rear, almost like a droop front. Not really though

That sound about right?

[CruisinMT]

Last week I broke my first part on my MS10 and it was a C hub. I bought some STRC aluminum C hubs for the AX10 dremeled about 1mm off of the axle housing and 1mm off of the C hub and they went on like butter. I also put on the steel Traxxas yolks and rustler/stampede shafts. Here are some pics.

[masonis1]

Looking good. Hows it crawling now? Mines doing great.