Birkin wrap

[waltermitty]

. . . well, partial wrap. I'm building a bare bones Birkin I picked up from Tom mid February, no interior, no fenders, no windshield, no heater, Kirkey seats. I was going to paint the nose some sort of metallic silver color to match the bare aluminum body. Someone suggest a wrap might look better. I found something that looks pretty good 3M "Brushed Aluminum", imagine that! Anyway, I'm wet sanding the nose with a 180 grit flexible sanding pad. I had planned on priming it but I might not have to. There are a couple of gouges and a little indentation where the badge is supposed to go I'm gonna give a little touch of filler. Gonna paint the inside flat black.

 

Because the tail lights are normally in the fenders I'm running some sealed led trailer lights that incorporate a license plate light, very bright, very light, very weatherproof, very cheap.

 

It is looking like I might pull off a 3 month build if I don't get hung up on the engine. Head is with Tom for machine work. All the big parts are either in my hands or Toms with the exception of the sump.

 

The 7s have gained weight over then years. I'm curious how much this one will weigh when I'm done. I found a really clever bathroom scale, digital, relatively cheap, measures up to 400 lbs. I have one and plan to buy another so I can weigh the car one end at a time. I will have to take it to a weigh station to get a weight slip as part of the registration process buy they only weigh to 10 lbs accuracy but they do give you a front/rear split.

[Dave W]

When I corner weight'd my Seven I only used one bath scale. I just made three spacers the thickness of the bath scale. You need to make sure your set-up pads are level. [ may have to shim ] It takes more time to move the scale to each of the wheels, but the wts where repeatable within 1lb. Dave W

[waltermitty]

Hmmm. I measured my scale. It is 1 foot square and about 1 1/4" thick. I need to build 3 dummy scales.

[wemtd]

Where are you able to register the car without fenders, (open wheeled)?

 

p.

[waltermitty]

Texas is very liberal, no fender, no windshield, no hood required.

[slomove]

Texas is very liberal...

:rofl:

 

As for the scale you will have a hard time to get the car exactly into the same balance position when you move the scale from one wheel to the next. A small fraction of an inch can make all the difference in the scale reading (keep in mind the front springs have at least 250 lbs/in stiffness). Also, the wheels tend to move a little horizontally when loaded and the bathroom scales don't like that at all. Another problem when adjusting the spring platforms is that moving one will change the reading of all four. Very difficult to optimize when you can not read all 4 at the same time.

 

At some point I built a set of 4 jigs with mechanical 300 pound bathroom scales ($10 each) where the wheels were sitting on a lever that reduced the weight force by a factor of 2 and eliminated the horizontal forces. Kind of worked but was still cumbersome to level precisely and load up with a jack. It was much easier to go to a friend who has a professional Longacre racing scale set.

[waltermitty]

Texas has pockets of liberals like Austin and the Rio Grande Valley. Kinda like rattle snakes they den up.

 

I think I might just get one more scale so I will have two scales. I am more interested in the side to side balance than the front to rear.

 

On the horizontal thing, the scale(s) I'm using are digital. I think I will using them with some makeshift turning plates, two pieces of vinyl tile 12x12 with some talc in between to allow for some lateral motion.

[Dave W]

The shiming is not for the scale thickness but the floor pads. You needed to level the set-up surface. Your typical garage floor in not level but slopes towards the door. I had to shim almost a 1/4" front to back. Once you have fabricated the leveling pads, make a note right on each pad as to which location the shimming pad is built up for and mark the floor locations. You are going to end up with four different pads thicknesses to get a level surface in your typical garage floor. Try to get all 4 pads within 1mm level. The lateral movement is not that great if you are just lift an 1/8" clear of the surface when changing out the scale. It will take a lot longer, probably 2 hrs Vs 1/2 hr, if you had professional corner wt set-up to use. Dave W

[waltermitty]

I have a surface that is level front to rear and side to side. I have never had a car I could really adjust so this will be my first attempt. I already use this surface and the tools I have to check/adjust camber, caster and toe on C7 Corvette.

 

I'm running Toyo R888R (195/50-15) on 15x7 wheels. The tire literature say they like negative 1 -3 camber. I planned to start at 2. Any recommendations? And maybe 20 psi (cold).

[Kitcat]

I use negative 2 and 18 psi rear, 16 front. I prefer the RA1's over the R888's, having run both. I have not tried the R88R tho

Edited March 25, 2017 by Kitcat

[Lightguy]

Wrap one with this.

No.... the plane.

 

 

https://images.fineartamerica.com/images/artworkimages/mediumlarge/1/p-40-pilot-pin-up-robert-alvarado.jpg

 

Don't forget the rivets and bullet holes

Edited March 26, 2017 by Lightguy