Detailing Cars… with Dan Noraker

I sent my new Chevrolet SS off to Dan Noraker to be detailed and Opti-Coated. Dan runs an auto detailing business out of his garage in Coon Rapids where he works on a steady stream of nice cars. Dan “corrected” and polished the paint before applying the Opti-Coat ceramic clear coating. The photos below show off his work nicely.

Milling Machine (setup)

I finally got around to unpacking and setting up the Grizzly Milling Machine. I brought the crate home in the Remackle trailer along with the stand I decided to by from Grizzly. The jib crane in the garage makes this sort of operation fast, easy, and safe.

First up assembly of the Grizzly machine stand (Part # G5944). The stand is light weight but surprisingly stable and well built.

Next disassemble the shipping crate to reveal the Grizzly G0619 milling machine. The machine and crate arrived in good shape with all the parts nicely packaged.

A single strap wrapped around the spindle casting provided a nicely balanced lifting point for the chain hoist. lifting the machine off the pallet and moving it to the stand could hardly be easier.

I’ve temporarily left the mill sitting on a couple of 2 x 4’s  as I decide exactly how to make a base under the mill to provide clearance for the vertical hand wheel. I think I’m going to make a simple wood base that raises the machine almost 3” higher than the stock height.

Lotus Exige… Seats

The Lotus Exige arrived with a pair of Carbon Fiber seats made by Tillett.

The Tillett B5 seat is designed to especially suit the Lotus Elise/Exige. It sits lower in the car to benefit taller drivers and is fairly narrow across the back.

It took only a couple minutes sitting in the car to realize I did not fit well in the seats. They are specifically designed to accommodate drivers taller than 6’ and held me in an uncomfortable position (especially across the back). Fortunately I secured the original seats for the Lotus from Mark Brandt as a part of the purchase. 

So… I set about removing the Tillett seats switching the original seats back into the car. The tight quarters surrounding the seat bases make this a surprisingly difficult task. My first drive in the car happened with the original seats re-installed. The seating position in the original seats suits my height fine but they are a tight fit across the hips.

There are a few manufactures making seats to fit the Lotus. While deciding what to do about the Tillett seats I spent some time reading about seating for the car on the Lotus Talk forums. The T3 carbon fiber seat by Tecnocraft is often recommended for folks of “larger” stature. After talking with Shinoo Mapleton at Sector 111 (Temecula CA) I decided to purchase one of the Tecnocraft seats they market as their CF Big-Bottom Seat.

Compared to the Tillett B5 seats the Tecnocraft T3 is considerably wider across the back. It is also designed to hold the driver in a slightly higher position in the vehicle.

I set about installing the Tecnocraft seat as soon as it arrived and am very satisfied with the comfort and driving position. The drivers seat in the Exige sits on an adjustable rail allowing the seat to be moved forward and back. The angle of the seat can only be changed using spacers (washers) under the rail system. I may well add a short aluminum washer under the rear mount to “tilt” the seat forward just a bit.

I’m not exactly sure what I’m going to do with the “extra” seats I now possess. I’ll probably sell the Tillett B5’s but I don’t think (for the moment at least) I’ll add a second Tecnocraft.

Lotus Wheel Alignment (Flyin’ Miata)

So… with the ride height and corner weights set and a preliminary set of alignment values I set about switching out the wheels for the Flyin’ Miata hub stands. While the hub stands have some big advantages (as we’ll see in a moment) setting ride height and corner weights on the stands would require some sort of “conversion” to account for the height of the stands and “rolling radius” of the tires (it’s not 1/2 the diameter and depends on tire pressure). Fortunately the combination of a scissors lift and wheel stands makes switching over to the hub stands quick and easy. The image below shows the Toe Bars on the hub stands with Carl’s thrust angle string system installed.

The first order of business is re-calibrating all four Toe Bars from the wheel hubs…

Then setting up to measure toe using tape measures between the hub stands underneath the car, and thrust angle using the strings.

The first round of hub stand Toe and thrust angle measurements agreed reasonably well with the values recorded from the ART laser toe gauge. In fact the measurements from the rear were nearly exactly the same (Toe IN: .062”) while the front showed a larger Toe OUT condition (.25” vs .20”). While I can not explain exactly why this occurred at least it showed the the error in the same direction… just a little more of it.

The image below shows the Flyin’ Miata hub stand system in place on the front right corner of the Lotus Exige.

By moving around the car a few times taking Toe angle measurements from the hub stands… I made sure the measurements repeated nicely. I then decided to bust out a set of wrenches to adjust the front tie rod ends and bring the front wheels into alignment.

Having the thrust angle strings right there in front of you while making adjustments to the tie rods is very nice. The fact that you can reach down and check the tape measurements anytime as well makes this process fast, intuitive, and confidence inspiring. With the car at waist level and wheels of the way the task is almost too easy. A couple of trips from side to side and about 3/4 of a turn with the wrenches brought the front wheels into alignment.

With the rear wheels consistently measuring Toe IN: 1.5mm I decided to leave them alone and moved on to removing the hub stands and putting the wheels back on the car for one last measurement with the ART Laser Toe Angle Gauge.

The results…

• Front: Toe OUT: .5mm (2 minutes)
• Rear: Toe IN: 1.5mm (12 minutes)

Or…

Lotus Wheel Alignment (Height, Weight, ART)

Setting up the “L” Shaped Garage to facilitate wheel alignment caused me to purchase the  Atlas wheel stands, Intercomp race scales, and ART laser Toe Angle Gauge. To align the Lotus Exige in particular I purchased the Flyin’ Miata hub stands. While the journey so has been interesting and fun the time has come to get to work and actually align a car.

In the interests of full disclosure… I’m writing this blog entry shortly after completing the wheel alignment on the Lotus. The process I’m going to describe here includes a number of additional steps included in this first effort. Specifically I chose to work from from both the Flyin’ Miata hub stands and also traditional “slip plates” in an effort to compare and contrast both the effort involved and the results.

As a first order of business I added weight to the drivers seat and disconnected the front sway bar. I used 40 lb. bags of water softener salt to ballast the drivers seat with 200 pounds of weight. The salt bags allow you to distribute the weight across the seating position nicely.

 

The Lotus Exige has a new set of adjustable suspension dampers (shock absorbers) and requires not only a wheel alignment but also ride height adjustment and corner weighting. The first step is to get the wheel stands leveled and the tops of the race scales all in the same plane. The first image below shows the left front stand with a race scale, and slip plates under the front wheel of the Lotus. Here you can see the line from the laser level striking the exposed perimeter of the top slip plate at both the front and rear wheels. The laser is a very convenient way to get the stands set up and close to level.

To ensure the wheel stands are level I have a small two-axis bubble level on top of each scale and also employed a long (78”) carpenters level between the stands.

With the stands leveled and a line level in place under the car we can now measure ride height with a small square. Lotus identifies four positions on the chassis where ride is measured. Holding the square up against these spots allows us to directly measure ride height at each position.

As seen here… There is plenty of clearance under the car to make these measurements.

Setting the ride height and corner weights is an iterative process. I first made sure the spring perches on the front and rear dampers were set to approximately the same position on the shocks. Then set the car down on the wheel stands and took a first set of ride height measurements.  

Next I lifted the car… removed the wheels… and made changes to the position of the spring perches to drive the ride heights up or down paying little (if any) attention to the corner weights. In the case of the Lotus I was able to get the ride heights where I wanted them on the second time through the process.

On the third pass through this process I made spring perch adjustments meant to drive the cross corner weights toward 50%. That is… I focused my attention on the scale readings largely ignoring the ride heights. This third iteration resulted in an 8 lb. difference (49.8%). Plenty good for now.

With the ride height and corner weights close I moved on to taking a set of alignment measurements using the ART Laser Toe Angle Gauge. The front wheels measured Toe OUT: 41 minutes… The rear Toe IN: 12 minutes. This works out to something like .20” (5mm) Toe OUT front and .06” (1.5mm) Toe IN rear.

The ART system sits nicely on top of the guards built for the wheel stands and is a very nice way to quickly measure Toe Angle on a vehicle. It is important to note that it does not tell you anything about thrust angle and requires the wheel remain in place on the car. Although adjusting the tie rod ends is probably possible with the wheel installed on the car it would certainly be difficult on a vehicle with as little space underneath as the Lotus.

ART Laser Toe Angle Gauge

Advanced Racing Technologies (ART) sells a very nice laser Toe Angle Gauge. I purchased a (slightly) used one off of a Porsche website to provide an independent way to measure toe angle. Carl Schulhof uses this gauge and his thrust angle strings as he aligns a vehicle. The gauge directly measures the angle between two wheels on opposite sides of a car using a laser (pointer), mirror, and a dial indicator on a pivot. It is very simple and easy to use.

The gauge has two rails. Each of the rails has a set of adjustable pins that engage the face of a wheel. To use the system you first (roughly) set the both of the rails so that the pins contact the wheel thru the centerline of the wheels. It is important to have the rails approximately parallel.

With the rails “roughed-in” you then set both assemblies on a flat surface and align the pins so that they can brought into contact (ends touching) with each other. This ensures that the two sides of the gauge are exactly aligned.

With rails aligned the laser shoots across the gap… and then bounces back (off the mirror)… Showing up on the target above or below the “shutter”. You then adjust the pivot mechanism to line the laser up in the groove on the target and set the dial indicator to “zero”.

Then place the calibrated components back on the wheels ensuring that the “return” laser beam from the mirror is in the same plane as the target (a piece of black construction paper works well for this). Now you “move” the laser spot until it aligns with the target using the adjustment knob on the pivot. The pivot on the gauge is designed such that .001” on the dial equals 1 minute of angle (60 minutes = 1 degree). Clockwise motion is Toe IN… Counterclockwise Toe OUT.

As I worked on the front end wheel alignment on my Lotus I measured the final wheel alignment to be 2 minutes Toe OUT (approximately .010” on a 17” wheel). It is easy to see why our friend Carl likes this gauge… It works well and inspires confidence.

FM Hub Stands… Thrust Angle?

After the long involved posting earlier it seems appropriate to spend a few minutes talking about thrust angle and how it relates to the Flyin’ Miata hub stands. The good folks at Flyin’ Miata used to offer the thrust angle gage pictured below. It was meant to be aligned to the centerline of the vehicle chassis and referenced while measuring toe with the hub stands. They recently discontinued selling it because it was not easy to use accurately. The image on the right shows the FM hub stands “enhanced” to facilitate thrust angle measurements.

 

Fortunately Carl Schulhof's string method for measuring thrust angle is easily adapted to the FM hub stands. The diagram below shows the details of Carl’s system with the equal length spacers supporting the strings at the “outboard” ends of the wheels and the measurement points in between.

The image here shows Carl’s thrust Angle string setup implemented on the Flyin’ Miata hub stands. The steel ruler at the far left hand side takes the place of one “spacer” while the ruler on the right is the measurement point for the front wheel. The rulers are aligned with the measurement points on the toe bars that we calibrated earlier. We set the string the same distance from the measurement point at all four corners and simply read the numbers on the (measurement point) rulers at the right.

As seen here… reading the strings on the rulers works very well.

All of the elements of this system are fastened directly to the hub stands which makes removal of the system no more complicated that unbolting the hub stands and setting everything aside. Furthermore when the system goes back on the car it stays remarkably well calibrated.

FM Toe Bar Calibration

The Flyin’ Miata hub stands facilitate toe measurements using a tape measure underneath the suspension components and body parts. The tape is stretched between the bars on opposite sides of the vehicle. First you have to “calibrate” the bars…

With the hub plate attached to the axle you pivot the bar using the adjusting knobs to make it parallel to the wheels (as shown below) . Flyin’ Miata recommends using a laser pointer held against the face of the wheel hub as a reference.

After quite a few “fits and starts” I’ve developed a calibration routine that works well for me. Instead of reviewing all my failed efforts I’ll just jump ahead the successful one here. The calibration of the FM toe bar required making a set of “spacers” to clamp between the hub plates and hubs to create a large stable base for the laser line level. Purchasing a high quality Bosch line and point laser made a huge difference as well!

Clamping a set of hook rulers to the toe bar measurement points and using the “trailing edge” of the laser line results in the high visibility and repeatable results shown in the images below. Especially important is fact that this “evolved” system allows the user to operate in a nearly “hands free” manner while adjusting the bar.

With the toe bars calibrated it is on to measuring toe!