to droop or to not droop
 

well im thinkin of making a custom chassis or tuber for my ax-10 scorpion n was jus wondering should i build it for full droop or semi-droop. wat works best for u guys or wats the setup on ur rigs?
im new n keen to get into this sport so any help would be greatful.
cheers n happy wheelin

Droop generally doesn't work on the rock around here. I find it to have negitive effects, the suspension just isn't very predictable. The truck sort of lingers about as the tires drop. The only reason I feel people find success in droop setups is because it lowers the truck and as a result corrects some of the higher COG / poor link angle issues they had.

Semi droop seems the be the proven setup around here. The trucks that I would call the best in the midwest are generally well tuned semi droops. The suspension seems to flow bettter. On rough climbs the suspension is very predictable, the truck rebounds far less as the grunt of the impacts are absorbed in the springs. The truck seems more stable and carries its weight and balance better as the axles rotate not drop.

I'm at the start of a tuber build myself. I was wondering which to go with also. I've looked at many videos and watched how they work. The full droop makes the truck so low that the low CG really helps out. I think I'm personally going to go with a semi droop being that I have shocks ready to go and see how I like it. Not a hug deal to change it to full I want to try it. good luck and post a build thread to get pointers along the way.

A droop suspension will work very well if the link geometry is sound. With droop you can easily get alot of axle unloading if the anti squat and roll center numbers are out of wack. A bad antisquat number would make it tough for the rig to climb steep inclines without unloading the front axle, and the a bad roll center number would net you alot of body roll when crawling.

I am the kind of builder that likes to attempt to get it right the first time (who wouldn't), but I have found that the best setups...both in my 1:1 crawling and rc crawling, have been just a trial and error method to see what really works on a particular chassis design and the terrain it's going to see.

I too am in the proces of planning/building a tuber (my first). I have setup the gemetry on my stock WK chassis, and like it a lot. My only gripe is the ground clearance, and it's abit top heavy. So, as a result, I'm planning my chassis around these requirements: Keep as much of my current geometry as possible while adding 1/2"-1" more ground clearance and keep the weight as low as possible.

Take a pic of your current rig (IF you like its setup) directly from the side and the top, print them out to full scale and start drawing.

You can also build into your first custom rig enough suspention geometry options so you can change the settings without having to build a whole new chassis. Then just drive drive drive.

hope this helps "thumbsup"

What numbers have worked for you? 100% anti squat? 50% anti squat. With your droop set-ups, have you found that higher or lower roll centers reduce body roll.

With my chassis, I started with a pretty middle of the road setup and then went from there into the "trial and error". Right now it's probably close to about 80-85 percent antisquat...which I still need to tune a bit. Where your roll center is set up is based alot on what height the center of gravity of your rig is vertically from the ground. On 1:1 rigs, a good rule of thumb starting point is to figure the top of the transmission bell housing where it bolts to the motor as the height of the COG.

On our smaller rigs it's a bit tougher to figure where the actual COG height is mainly because these crawlers don't usually follow the same weight layout as a 1:1 rig.

What I ended up doing to get me started was take measurements of the link capture locations off of a 1:1 crawler that I figured worked pretty well. I plugged these into an Excel spreadsheet 4-link calculator that is available over on Pirate4x4.com. Then it was just a matter of scaling down the 1:1 measurements to match the size of crawler chassis I wanted to build.

It did take some time in the beginning with all the math and scaling, but it gave me a nice reference point to start tweaking from there. 8)