Shape_Shifter Builds a Sawback
 

Goofing around with trucks again.....

• Hardened drive line
• Anti spring-wrap traction bars
• Revolver shackles
• RC4WD Ultimate Scale 100mm rear shocks
• 2590Kv sensored brushless motor
• Savox SB-2270SG brushless servo
• Gmade chassis mount servo tray
• RC4WD soft leaf springs
• 3Racing winch
• RC4WD steel beadlock wheels
• RC4WD Rock Crusher tires
• 6 watt Cree LED headlights to come..... :twisted:

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Re: Shape_Shifter Builds a Sawback
 

Nice build SS
How do you like the RC4WD springs so far? My brain cant decide to grab them or not

Re: Shape_Shifter Builds a Sawback
 

Thanks!

I think they are perfect for the Sawback. I had them on a Hilift a while back and did not like them on that truck for some reason. They just seem to work really well with the Gmade shocks. A big HOWEVER, you have to make traction bars or some sort of axle-wrap preventors. Otherwise they will wind like a clock spring! :shock:

Re: Shape_Shifter Builds a Sawback
 

With the traction bar setup you have , how well does the suspension cycle. Also what do ya think of the brushless setup.

Re: Shape_Shifter Builds a Sawback
 

I was wondering what the traction bars would do but I performed many squish tests on the bench. It seems like they don't impede the travel at all on the trail. No more than say a panhard bar would effect coils in front. Definitely no problem in back with the Revolver shackles.

The motor/ESC setup is as good as it gets for $86. The ESC is programmable up to a point. I have drag brake set at max (which is only %30) but it still rolls on steep drops. I wish it would go higher on drag brake but it just means you have to work your finger a little more. I love the sensored systems because you can adjust expo on your transmitter and dial in a creep with high torque. I almost bought a lower KV motor but this one works fine. I am going to put a 10t pinion on and see if it helps the drag brake at all.

Re: Shape_Shifter Builds a Sawback
 

New driver...

http://imagizer.imageshack.us/v2/xq90/838/vo4e.jpg

Re: Shape_Shifter Builds a Sawback
 

Looking good...

Re: Shape_Shifter Builds a Sawback
 

Thanks!

Hoping to get your rear bumper and sliders Pedro!

Re: Shape_Shifter Builds a Sawback
 

You know I have been doing some more wheeling and studying the long traction bar setup. It does not seem to be restricting travel on the trail but the geometry just doesn't add up. I changed the traction bars to match the natural pivot point of the leafs. The difference is barely noticeable on the trail but it makes more sense "on paper".

http://imagizer.imageshack.us/v2/xq90/835/2lqh.jpg

Just picked one of these kits up..in the process of building..one question..what is "axle wrap"?

Re: Shape_Shifter Builds a Sawback
 

Good question.

If you are doing slow, technical driving like rock crawling, you are susceptible to "leaf spring wrap" or "axle wrap".

Lets say a tire gets stuck between a rock and a hard place - The motor and drive line will continue to to apply torque to the axle but the wheel wont spin because it's jammed. So instead, the axle will continue to turn against the leaf springs.

Watch at about 1:45 in this video.
https://www.youtube.com/watch?v=hX-kd2JcnJg

You can see the springs on the left side of the screen begin to wrap a little. This happens, to some extent, to all vehicles with driven leaf spring axles. If your leaf is really soft (best for crawling) it can bend to the point of actually making a kink in the leaf.

That's a great looking Sawback! That tire and wheel combo looks perfect.

Where did you get those Revolver shackles?

I'm also anxious to see the Cree LEDs!

Sent from my SCH-I535 using Tapatalk

Re: Shape_Shifter Builds a Sawback
 

Thanks!

The Revolvers are actually called Shooter Shackles made by RC4WD. I guess there must have been a licensing issue so they couldn't call them revolvers.

Re: Shape_Shifter Builds a Sawback
 

I finally got a chance to go out and play in the dirt with the Sawback. I tried to find a puddle but you can see from the pics that the drought is pretty bad.

I am loving the suspension setup! Revolvers front and rear with 100mm shocks really let the Sawback stretch. Not the perfect crawler but damn good for leaf springs.


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Here's a shot with Mini-Me.

http://imagizer.imageshack.us/v2/xq90/836/6mg3.jpg

I love the Mini-Me!

One of my front leaf springs is bent. I'm not sure if it's from axle wrap or from a roll down a hill.

How about some photos of the shocks and the suspension at full droop without the body? That way we can see the increased suspension travel more easily.

Sent from my SCH-I535 using Tapatalk

Re: Shape_Shifter Builds a Sawback
 

Okay, Ill post some this afternoon.

Re: Shape_Shifter Builds a Sawback
 

I dont know if this is good or bad but its better than stock.

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Also, I added some lead behind the wheels. I wish I added more inside the wheels before the wheels were put together but I am too lazy to rebuilt all of them HA!

http://imagizer.imageshack.us/v2/xq90/836/hgim.jpg

Re: Shape_Shifter Builds a Sawback
 

Those shots are great! Thanks! That's definitely more travel than stock.

Those Rock Crushers look great on there. How do they perform? They're 1.9 wheels, right?

Re: Shape_Shifter Builds a Sawback
 

Thanks! The Crushers are a medium kind of compound and they seem great on hard dirt clods. I will have to see how they do on granite. I think they look great too.

Yeah the wheels are the 1.9" 5 spoke steel .

You can kinda see how the shooters don't really rotate with the soft springs. Instead, the springs twist. You could probably just make some extender shackles that don't rotate and get the same performance with the soft springs.

The shackles do twist a little bit but not as much as I thought they would.

I bent my stock leaf springs so I'll need new ones. I don't like that the RC4WD ones are red though.

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