Whats the formula

[TCBronson]

I have a limited amount of experience with RC. I have had a couple of Tamiya's , Fox and Unimog. Axial XCS 10. Then 3 WPL Tacoma's, just because they are so cheap.


Now I want to build a realistic 1/10th scale rig, my budget is cheaper the better or under $400 if possible.


So what is the magic formula to build a scale RC that performs realistically, meaning the rig isn't jerky and the suspension isn't bouncy, but the whole rig is smooth running. Is it the motor, ESC, servos, or the combination?



I am ok with starting with a kit or RTR, or even a builder kit. I am not brand loyal, yet.


Any suggestions are appreciated.
Thanks!
Tom

[donny8594]

Realistic feel. Brushed motor, 2s battery, weak servo, stiff suspension. Oh and don't forget small tires and a hardbody.

[TCBronson]

Any specific parts that you know that work, like motor, servos, ESC, battery, chassis, size of wheel and tires?

[Jim85IROC]

Originally Posted by donny8594

Realistic feel. Brushed motor, 2s battery, weak servo, stiff suspension. Oh and don't forget small tires and a hardbody.

I would make one change... the suspension needs to be much softer on an RC to simulate realistic movement. Because weight doesn't scale down the same way as size, RCs end up way too light to simulate the movements of full size cars. The only way to compensate for that is to add a ton of weight to the vehicle, or soften the suspension. Full size vehicles are set up with a significant amount of suspension droop, where most RCs, especially crawlers, have little to no droop.

[JDM74]

Viscosity doesn’t scale at all so you will need to run very light weight fluid or none to get the suspension to move like a 1:1. I took the oil out of the shocks on my Blazer and it made a big difference with how realistic the suspension moves. Be warned though, this will hurt overall performance.

[Jim85IROC]

Originally Posted by JDM74

Viscosity doesn’t scale at all so you will need to run very light weight fluid or none to get the suspension to move like a 1:1. I took the oil out of the shocks on my Blazer and it made a big difference with how realistic the suspension moves. Be warned though, this will hurt overall performance.

oil viscosity and spring rate both need to be adjusted to compensate for the non-scale weight differential.

If our 1:10 cars were 1:10 the weight of full size cars (can you imagine a 400lb 1:10 RC!?), it would be a very different hobby!

[Almighty Malach]

Originally Posted by Jim85IROC

oil viscosity and spring rate both need to be adjusted to compensate for the non-scale weight differential.

If our 1:10 cars were 1:10 the weight of full size cars (can you imagine a 400lb 1:10 RC!?), it would be a very different hobby!

Scaling weight down is a cubed function of a scaled dimension. A 1" x 1" x 1" steel cube will only weigh 1:1000 of a cube that is 10" x 10" x 10" since 10 x 10 x 10 equals 1000. So, a true scale RC of a 4500lb rig would only need to be 4.5lbs to be true to scale.

[Jim85IROC]

Originally Posted by Almighty Malach

Scaling weight down is a cubed function of a scaled dimension. A 1" x 1" x 1" steel cube will only weigh 1:1000 of a cube that is 10" x 10" x 10" since 10 x 10 x 10 equals 1000. So, a true scale RC of a 4500lb rig would only need to be 4.5lbs to be true to scale.

Good point.

[Inspector86]

For the most realistic action, I would start with one of the TRX4 models with locking diffs and 2 speed trans basically anything except the Sport. For most realistic smooth power I recommend an HW1080 ESC paired with HH Trailmaster Sport 550 21T brushed motor. Finally a comment about suspension set up. The stock TRX4 shocks are smooth, leak free, adjustable and Traxxas offers a range of optional spring rates which allow you to fine tune them to your driving style. When setting up the suspension for realistic movement I recommend a static droop of around 50% or 1/2 of the total suspension travel. Droop is simply the amount the suspension compresses with the static weight of the truck setting on the wheels.

[TCBronson]

Thank yo to all taht have responded!

[donny8594]

Originally Posted by Jim85IROC

I would make one change... the suspension needs to be much softer on an RC to simulate realistic movement. Because weight doesn't scale down the same way as size, RCs end up way too light to simulate the movements of full size cars. The only way to compensate for that is to add a ton of weight to the vehicle, or soften the suspension. Full size vehicles are set up with a significant amount of suspension droop, where most RCs, especially crawlers, have little to no droop.

Good point but it seems it would depend on the full size vehicle your replicating. My 1:1 jeeps were stiff as wedding wieners, my current 1:1 feels like it does yoga.

[donny8594]

Originally Posted by Inspector86

For the most realistic action, I would start with one of the TRX4 models with locking diffs and 2 speed trans basically anything except the Sport. For most realistic smooth power I recommend an HW1080 ESC paired with HH Trailmaster Sport 550 21T brushed motor. Finally a comment about suspension set up. The stock TRX4 shocks are smooth, leak free, adjustable and Traxxas offers a range of optional spring rates which allow you to fine tune them to your driving style. When setting up the suspension for realistic movement I recommend a static droop of around 50% or 1/2 of the total suspension travel. Droop is simply the amount the suspension compresses with the static weight of the truck setting on the wheels.

Can not agree more on the trx4...

[JDM74]

I’ll say it again because l’ve been down this roady already: Even if you get the shocks setup with 50% droop you are going to need to either drop your fluid viscosity down to 10 or none or open up the holes in the piston a lot to get the suspension to move realistically. The stock fluid is too thick to let the suspension react to small higher speed bumps like a 1:1.