V1 DIY Front End Alignment

[Keckster]

Not to highjack mid thread but if anyone is looking to assemble the 3d printed laser alignment system by diyfabshop I have modeled and used an adapter to mount to the goblin cage utilizing a worm gear clamp. Utilizing this system I was able to get the car the most stable it has ever felt! STL file posted below and in the 3d printing thread.

My most recent alignment stats are:

Front Left:​

• Caster: -9.1°
• Camber: -0.8°
• Toe: 1mm in

Front Right:​

• Caster: -9°
• Camber: -0.8°
• Toe: 1mm in

Total Front Toe: 2mm in​

​

Front Axle Notes:​

Tire Temperature normalized perfectly across the tread at 15psi during competition with chalk mark wearing perfectly.​

​

​

Rear Left​

• Camber: -1.9°
• Toe: 1mm in

Rear Right​

• Camber: -1.9°
• Toe: 1mm in

Total Rear Toe: 2mm in​

​

Rear Axle Notes:​

Tire temperature was low on the inside shoulder but the chalk mark was showing full tread usage at 18psi​

​

​

Disclaimer: I have modified my suspension this past winter moving pickup points, adding spacers to the wheel hubs, and raising the ride height to play with roll centers so my alignment settings may work for me and not a stock chassis.

 

[David]

Not to highjack mid thread but if anyone is looking to assemble the 3d printed laser alignment system by diyfabshop I have modeled and used an adapter to mount to the goblin cage utilizing a worm gear clamp. Utilizing this system I was able to get the car the most stable it has ever felt! STL file posted below and in the 3d printing thread.

View attachment 57340 View attachment 57343

My most recent alignment stats are:

Front Left:​

• Caster: -9.1°
• Camber: -0.8°
• Toe: 1mm in

Front Right:​

• Caster: -9°
• Camber: -0.8°
• Toe: 1mm in

Total Front Toe: 2mm in​

​

Front Axle Notes:​

Tire Temperature normalized perfectly across the tread at 15psi during competition with chalk mark wearing perfectly.​

​

​

Rear Left​

• Camber: -1.9°
• Toe: 1mm in

Rear Right​

• Camber: -1.9°
• Toe: 1mm in

Total Rear Toe: 2mm in​

​

Rear Axle Notes:​

Tire temperature was low on the inside shoulder but the chalk mark was showing full tread usage at 18psi​

​

​

Disclaimer: I have modified my suspension this past winter moving pickup points, adding spacers to the wheel hubs, and raising the ride height to play with roll centers so my alignment settings may work for me and not a stock chassis.

I got the real deal coming soon.

 

[David]

@Keckster here is what the finished product looks like. Took a while to make everything line up correctly. I will ask Kent to upload it to his website. If anyone whats to use his system.

 

[David]

I like your idea or the worm gear it way faster, just seems like it could scratch the frame when tighten.

 

[Keckster]

I like your idea or the worm gear it way faster, just seems like it could scratch the frame when tighten.

probably would scratch it a bit. My frame is already scratched up so it doesn't bother me a ton. I've cut radiator hose in half before when clamping stuff and that generally protects it

 

[David]

@Keckster I started to mock everything up and my ocd didn't let me leave it and also the laser was at it auto leveling. Did you leave your extruded aluminum in an angle or did you level it with your design? I have a new adapter printing which has the 6.8⁰ built-in so it can be level.

 

[Keckster]

@Keckster I started to mock everything up and my ocd didn't let me leave it and also the laser was at it auto leveling. Did you leave your extruded aluminum in an angle or did you level it with your design? I have a new adapter printing which has the 6.8⁰ built-in so it can be level.

The adapter I made has a 5 degree angle in the model.

 

[Desert Sasqwatch]

The side of the cage hoop on the track frame is angled down 5 degrees toward the front - at least on the 'early' frames. A difference to this angle will depend upon the rake of the entire frame relative to the ride heights set for the front and rear suspension, if sitting on it's wheels, or any variation in the slope of the surface it is parked on. If the system being used doesn't 'self level' then this angle variation needs to be accounted for in the measurements. BTW, this also needs to be considered and measured for in the side to side variance from 0 degrees level just as the fore and aft measurements. Accuracy is dependent upon the datum all of the angles and values are measured against. As many builders have experienced, a very slight change in the setup of the suspension geometry can have a big difference in the handling and feel of the car.

 

[David]

The side of the cage hoop on the track frame is angled down 5 degrees toward the front - at least on the 'early' frames. A difference to this angle will depend upon the rake of the entire frame relative to the ride heights set for the front and rear suspension, if sitting on it's wheels, or any variation in the slope of the surface it is parked on. If the system being used doesn't 'self level' then this angle variation needs to be accounted for in the measurements. BTW, this also needs to be considered and measured for in the side to side variance from 0 degrees level just as the fore and aft measurements. Accuracy is dependent upon the datum all of the angles and values are measured against. As many builders have experienced, a very slight change in the setup of the suspension geometry can have a big difference in the handling and feel of the car.

I just finished testing out my leveling platforms and they work great. I knew my garage wasn't level but wow its way off. The lasers are auto leveling so everything will always be leveled. I just didn't want the Extruded aluminum to be on an angle which was limiting the lasers to properly self level. Now I have to see where I start the alignment process lol. I also got 3 bags of 80lb concrete on the driver seat.


Seems like the 3d printed alignment tools will work good. @Keckster seems to already used it.

 

[David]

Ok so I started with the alignment and im stuck already. 1st thing I want to do is the caster but im getting mixed numbers because the DF way and the normal 20⁰ rotation method.

DF way digital gauge 0⁰ on the tunnel cover facing the same way of the side your doing.
Diverside 8.5
Passenger 8.3

The 20⁰ rotating method Caster = (A - B) x 1.43. I get 1.1⁰ on the driver and 2.3⁰.

What im I doing wrong shouldn't the DF way match the 20⁰ method?

 

[Rttoys]

Rotating method
Let’s say dr side
rotate 20° to the left, set zero.
rotate past center to 20° right.
what is that number?

same on pass side just opposite rotation

 

[Keckster]

The 20⁰ rotating method Caster = (A - B) x 1.43. I get 1.1⁰ on the driver and 2.3⁰.

What camber measurements did you get at turn in and turn out? + and - signs are very important for your measurements

 

[David]

What camber measurements did you get at turn in and turn out? + and - signs are very important for your measurements

Great question I have a Klein 935DAG doesn't display a + or - just has an arrow up or down.

Digital Angle Gauge and Level - 935DAG | Klein Tools

The Klein Tools Digital Angle Gauge and Level can measure or set angles, check relative angles, or can be used as a digital level. The strong magnetic base attaches to ferromagnetic surfaces such as conduit. Along with dual measurement ranges of 0 to 90-Degree and 0 to 180-Degree, this tool has...

www.kleintools.com

 

[Rttoys]

I don’t have a picture of my setup on the front, but this is it on the back.

 

[David]

FL at zero I have +.1 arrow going down, 20⁰ in - 1.7 arrow going up, 20⁰ out +2.6 arrow going down.

 

[Keckster]

FL at zero I have +.1 arrow going down, 20⁰ in - 1.7 arrow going up, 20⁰ out +2.6 arrow going down.

That’s roughly 6.15 degrees of caster using the eq (|A| + |B|) *1.43

so long as one is positive camber and the other is negative you can just add them. If they are both positive or both negative you gotta take the difference

 

[David]

That’s roughly 6.15 degrees of caster using the eq (|A| + |B|) *1.43

so long as one is positive camber and the other is negative you can just add them. If they are both positive or both negative you gotta take the difference

Ok that a little closer to DF measurement which is 8.5 still not close. Which way is better and more accurate? Why the difference?

 

[David]

Rotating method
Let’s say dr side
rotate 20° to the left, set zero.
rotate past center to 20° right.
what is that number?

same on pass side just opposite rotation

-4.5

 

[Rttoys]

Also, move the gauge to the center of the hub.

 

[Keckster]

I’m sure there’s some sort of error in both the turn method and the DF method. My angle gauge doesn’t fit on the bolts where they measure from but getting it to sit perfectly in line with the car and vertically on just the bolts seems like it could be inconsistent. As for the 3d printed mounts make sure your wheel adapters are pushed in all the way when you take the measurement. Mine were slightly loose and I’d have to push them in against the wheel to get consistent readings