Droop Vs. others

[run2jeepn]

Originally Posted by KRAWLR4life

Well, technically, YES cuz my eyes and wrists hurts too!!!
It was good getting to know you and your thoughts behind suspesion setups.
Keep up the good work with the Biz!
~John

Thanks

[cartronicshn]

I think all suspensions suck.. j/k, i have rigs with conventional suspensions, torsion stick rigs, and i'am currently waiting on a tuber to try a droop suspension set up, and this thread has been very helpful, thanks to all involved

[BESRK]

Interesting reading and a lot of good info. I'm new to this RC Crawling. However, I have built a few coilover 1:1 rigs/buggies and work on them all the time. I find myself trying to compare RC rigs to 1:1 rigs but as stated earlier, you can't do it (unless you make the RC rigs really heavy). Because the weight isn't to scale, you are able to do some really cool stuff (like using springs to "suck" up on the shocks..). Can't do that in the real world.. or can you? Personally, I built my 1:1 buggy on the bumpstops. I use 14" travel coilovers up front and 16"ers in the rear. I build the rig with no springs and then I install springs to get about 3-4 inches of shock stickout. That's only to make it a bareable ride. Otherwise, you'd knock your teeth out on every bump. The rest of the 10 and 12 inches of shock travel is set up for droop. This allows a few advantages (many of which have already been covered here). I already built in 24" of ground clearance to my tranny skid but with the droop chassis, if I high center, the axles frequently droop enough that a tire or two can still pull my forward. Of course, it helps that I use UHMW self-oiling plastic for my skid.. stuff slides like ice on the rocks. I have a buddy who's rig rides on similar shocks but it's almost all stickout (uptravel). He isn't nearly as stable in the twisty stuff. Another thing that I've incorporated (and it was mentioned earlier in this thread) and it's worth its weight in gold.. are winches front and rear that suck up the suspension. When my nose is skyhigh and I'm teetering on a rear endo, I suck up the front winch till I hit the bumpstops. If I'm going to sidehill a long stretch, I suck down both winches almost to the bumpstops to keep from unloading. However, if I'm dropping over a ledge (up to about 6ft so far), I leave the rear free to droop. Some would think that leaves the rear free to unload and cause a front endo. However, in real life, it allows the back tires to drag along on the rocks to help control the speed. As I build my TXT tuber, I plan on using a similar setup (minus the winches). I'll use some long travel shocks (Savage), set them up with a little stickout probably using soft springs. I wish they made a pistol grip 4 or 5 channel radio that would allow a servo to be setup as a winch to suck down the suspension. It would be fun to experiment with a front suspension winch... a rear suspension winch.. and a single winch that sucks both suspensions down to the bumpstops to stop unloading. In effect, the light springs inside the shocks pulling up on the shock rod are already doing this.. I'd just like to do a conventional suspension and have manual control over it.

Edit: As for the suspension changing wheelbase while drooping. This can be minimized by running links that are parallel to the ground or close to it. The steeper the link angle from the axle up to the frame, the worse the axles are going to "swing" toward the center of the vehicle.

[Cole82]

I'm back any more questions?

[RD400]

I found that a 50/50 droop to sprung setup works extremely well for me. I run a .55 inch internal spring under the piston and a Losi 2.75 inch external spring at each corner. At ride hight the shock is at half droop with 2 springs holding it there. I get the advantage of a droop setup with the mechanical traction of a suspended rig.

Ride hight at rest is 2.75 inches with a max belly clearance of 3.20 inches. All of that being said, droop or sprung, nothing means a hill of bean if the link geometry is off. Get the squat/anti-squat right and almost any rig will crawl fairly well.

[Cole82]

Originally Posted by RD400

All of that being said, droop or sprung, nothing means a hill of bean if the link geometry is off. Get the squat/anti-squat right and almost any rig will crawl fairly well.

EXACTLY and this is what MOSTpeople don't take the time to do.

[RD400]

I have had the same basic design for about 20 months now, lots of tweaking to get the geometry right. I have crawled against a lot of different people and only felt out-classed by Dezfan. I think it is best to find a design that works for your terrain and your driving style. After that, drive the day lights out of it and do the old "one change at a time" method to improving the performance.

[JohnRobHolmes]

For the weight being scale, I think you can build a rig to scale weight. Think of a block of Steel 10"x10"x10", then think of the 1/10th scale block that is 1"x1"x1". In terms of volume, the 10" cube will have 1000 times the amount of steel and weigh 1000 times more. Same for a crawler. A 5lb 1/10th scale crawler is 5000lbs scale weight. Totally in line with a real vehicle.

[ON THE FARM]

So in a droop set up you would rather have your suspension move slower (thicker shock oil)? Or do you want a thinner oil, making youe suspention faster?

[pbfrk4life]

Originally Posted by ON THE FARM

So in a droop set up you would rather have your suspension move slower (thicker shock oil)? Or do you want a thinner oil, making youe suspention faster?

I like mine to move slower, it makes the suspension more predictible.

Ive been working on a drooper for a couple of months now and here is what i have seen.

Pros
Lower COG
Axles drop down when hung up
Little body roll on sidehills
Great for climbing steep inclines

Cons
Torque twist in the back left
Takes a lot of tuning

Im trying to stay open minded, but i just cant think of many cons. I have been very happy with my suspension setup. It just takes a lot of tuning sense you cant buy shocks setup for droop.

[run2jeepn]

Originally Posted by pbfrk4life

I like mine to move slower, it makes the suspension more predictible.

Ive been working on a drooper for a couple of months now and here is what i have seen.

Pros
Lower COG
Axles drop down when hung up
Little body roll on sidehills
Great for climbing steep inclines

Cons
Torque twist in the back left
Takes a lot of tuning

Im trying to stay open minded, but i just cant think of many cons. I have been very happy with my suspension setup. It just takes a lot of tuning sense you cant buy shocks setup for droop.

See here is where I just get lost again. You say Pro's.. And list Lower COG. Well you can set up any 4 link Sprung set up to set just has low. You can have the links just as flat. By one either running shorter shocks or changing the angle of them and so on. On the Dropping the axle part. Just sounds goofy to me still. I can see Droop helping on Sidehills. Steep inclines I don't see it being any better then other setups. Speical a Stick set up. Just not possible b/c of the break over point. We need to post some videos showing how this works and why. And what makes it so much better then a Correctly Set up Sprung rig.

[pbfrk4life]

Originally Posted by run2jeepn

See here is where I just get lost again. You say Pro's.. And list Lower COG. Well you can set up any 4 link Sprung set up to set just has low. You can have the links just as flat. By one either running shorter shocks or changing the angle of them and so on. On the Dropping the axle part. Just sounds goofy to me still. I can see Droop helping on Sidehills. Steep inclines I don't see it being any better then other setups. Speical a Stick set up. Just not possible b/c of the break over point. We need to post some videos showing how this works and why. And what makes it so much better then a Correctly Set up Sprung rig.

Ok, im sorry i wasnt clear enough. For lower cog, i say that because droop makes being a belly dragger easier for me. With a sprung setup being a belly dragger and you get high centered your stuck unless you can rock off. With droop being a belly dragger it lets the axles drop some and try to get traction. The axles dropping might seem funny, but it works real well. To me this is the biggest advantage.

As for it being better in other areas, i guess its personal preference.

[run2jeepn]

Originally Posted by pbfrk4life

Ok, im sorry i wasnt clear enough. For lower cog, i say that because droop makes being a belly dragger easier for me. With a sprung setup being a belly dragger and you get high centered your stuck unless you can rock off. With droop being a belly dragger it lets the axles drop some and try to get traction. The axles dropping might seem funny, but it works real well. To me this is the biggest advantage.

As for it being better in other areas, i guess its personal preference.

No I understand how that would help. But the amount of drop it would need to do any good from getting off from being high centered would also hurt in many other spots aswell as the rear end would try and walk under the chassis.

[G-crawler]

a little bit off topic..can u run a hustler without the droop setup?

[pbfrk4life]

Originally Posted by run2jeepn

No I understand how that would help. But the amount of drop it would need to do any good from getting off from being high centered would also hurt in many other spots aswell as the rear end would try and walk under the chassis.

I have never had any issues with my rear "walking" under my chassis.

I think the only way that you will understand droop is to try it. If you dont like it change back to sprung.

[Mnster]

Originally Posted by RD400

I found that a 50/50 droop to sprung setup works extremely well for me. I run a .55 inch internal spring under the piston and a Losi 2.75 inch external spring at each corner. At ride hight the shock is at half droop with 2 springs holding it there. I get the advantage of a droop setup with the mechanical traction of a suspended rig.

Ride hight at rest is 2.75 inches with a max belly clearance of 3.20 inches. All of that being said, droop or sprung, nothing means a hill of bean if the link geometry is off. Get the squat/anti-squat right and almost any rig will crawl fairly well.

That is a exact replica of the setup I have been running on for a while now. I ran droop and hated it, didn't like the chassis raising and throwing the COG off. I ran coils and got by for a while. After changing over to 50/50 it was like a totally different truck I am now able to take lines that were impossible in the past. Another advantage of 50/50 is you have the small loose spot, that allows for low pressure suspension articulation. Works like a progressive spring.

[Cole82]

Originally Posted by run2jeepn

No I understand how that would help. But the amount of drop it would need to do any good from getting off from being high centered would also hurt in many other spots aswell as the rear end would try and walk under the chassis.

If the rear end is trying to walk under the truck your links need some mojor changes.

[BESRK]

Originally Posted by johnrobholmes

For the weight being scale, I think you can build a rig to scale weight. Think of a block of Steel 10"x10"x10", then think of the 1/10th scale block that is 1"x1"x1". In terms of volume, the 10" cube will have 1000 times the amount of steel and weigh 1000 times more. Same for a crawler. A 5lb 1/10th scale crawler is 5000lbs scale weight. Totally in line with a real vehicle.

Since our scale crawlers are 1/10th scale wouldn't you just divide the real vehicle weight by 10 to come up with the scale weight? That would be 5000lbs/10=500lbs for the crawler. Am I doing that right? Wouldn't 5lbs be 1/100 of 5000lbs? If so, that's why it would be crazy to try and do scale weight... maybe I'm dumbing this all up..

[Cole82]

Originally Posted by BESRK

Since our scale crawlers are 1/10th scale wouldn't you just divide the real vehicle weight by 10 to come up with the scale weight? That would be 5000lbs/10=500lbs for the crawler. Am I doing that right? Wouldn't 5lbs be 1/100 of 5000lbs? If so, that's why it would be crazy to try and do scale weight... maybe I'm dumbing this all up..

No john is right.
I think weight is cubed if I remember right. Your dealing with mass and volume not just size.

[JohnRobHolmes]

Read my post again and think about it. There is more than one dimension that is shrunk by 1/10th.

The scale Chino built rigs I saw moved just like the real thing, it was cool to watch.