Here we go again! Zuffenhaus MS RSR project...

[eimkeith]

Thanks!

I was able to make more progress on the oil cooler mounting today; as well as significant strides on the driver's side battery box.

This is where I left off with the oil cooler duct yesterday:



To get the cooler properly positioned, I had to consider the route of the hoses through the front bulkhead/duct sheet metal, like in the RSR reference picture posted previously.

I started by sitting down and roughing some models of 30, 45, and 60 degree -16 crimp fittings and printed them as cross sections to mock up the hose routing.





This allowed me to visualize where the hoses would pass through the trunk, and make decisions about hole placement (and consequently cooler position)



Based on this, I've temporarily hung the cooler - it may be adjusted for height still, and it is very likely that we'll have to modify the end tanks to get the bumper over it (although I could probably omit the rubber isolators it's currently mounted on to gain about 7 more mm.)






As I mentioned, I was able to make headway on the driver's side battery box and fuse panel arrangement also.

The historic car had battery box deletions, so we're recreating those while visually backdating the trunk wall.

Here is the trunk wall and battery box roughed in, before trimming off the back of the box



And this is where I stopped for the day:



Battery box in, and cut off. I'll work toward making the blanking plate tomorrow; I'll have to determine the actual size of the brake duct hose that passes through it before I fabricate and install it, so some research will be required.
keith.

(sent from my rotary dial phone.)

[preston_brown]

Keith,

This is really great documentation and nice work. Thanks very much for posting these details.

[911 tweaks]

very nice keith...what is the black conv top car in the 2nd to last pic in the upper rt corner of the pic behind the red mini...a 968 possibly...? the car w/ 2 exh pipes on its left rear side...
great work as always...thx for sharing...bob

[scootermcrad]

Looking great! What oil cooler is that, you have mocked up there? I really like the angled side tank design to get the fittings started in the right direction.

[eimkeith]

Bob, that's a 997. Scoot, the oil cooler is a B&B iirc.


keith.

(sent from my rotary dial phone.)

[78-911SC]

Keith once you have all the panels set correctly do you have a way to mark them so when you dismantle for paint you can put them back exactly as the margins were originally set?

[scootermcrad]

Originally Posted by eimkeith

Scoot, the oil cooler is a B&B iirc.

Great! Thank you!

[eimkeith]

Originally Posted by 78-911SC

Keith once you have all the panels set correctly do you have a way to mark them so when you dismantle for paint you can put them back exactly as the margins were originally set?

Yes. The doors are removed by pulling the pins once the hinges are set, so they self-align. The fenders and hood will get pilot holes drilled in them so that the stem of a pop rivet can be used as an alignment tool for reassembly.

The chassis will go out for all over paint in GP white, then return for panel assembly and flare bonding. Then it will go to the paint shop again for the silver exterior paint.

Hopefully within a week or so!


keith.

(sent from my rotary dial phone.)

[78-911SC]

Keith thanks. Just a couple more questions if you don't mind. What size rivet? Do you leave it in after assemble? If no what do you do about the hole if nothing do you touch them up? I have built my own plane so I have different sizes on hand. If you do remove the rivet than instead of rivets do you think clecos would work?

[eimkeith]

I use the back side of a small rivet - not the head. And this is for hot rod builds and/or backdates, I wouldn't drill pilot holes in the early cars, personally.

After the bolts go in and everything is torqued, the rivets slide out and just the minuscule hole remains.

I'll show it when I get to that point, so there's no mystery.


keith.

(sent from my rotary dial phone.)

[eimkeith]

Additionally, the underbody schutz will seal these holes on a street car (fenders)


keith.

(sent from my rotary dial phone.)

[eimkeith]

Nothing post-worthy today, save for a mechanical failure with our printer:



(Was just about to make a little tool, too!)


keith.

(sent from my rotary dial phone.)

[eimkeith]

So, the repair part came in for the printer today, so I got back to tool making.



These are a couple of forms for re-contouring the fixed quarter window corner trim pieces - I'm going to try my hand at making the RS/RSR quarter window trim that we need for the Mary Stuart.

Aside from that, I worked on the fuel cell.


keith.

(sent from my rotary dial phone.)

[eimkeith]

So, the fuel cell.

The cell supplied by the owner was tweaked and wouldn't sit properly in the trunk, and had the same issue in other chassis it was tried in.

Not a problem, really, since we're replicating the dual through-hood dry breaks of the historic car:



The Mary Stuart, being an evolved 1973 RSR, used a 110L plastic tank, like so (shown here modified for dual fills)



We're using a cell so that the car can be raced safely. This presents an issue, as the cell, as-designed, sits too far forward and must be relocated for the fills to work in their original locations.

Here's the client's cell - you can see where it was making contact with the body and wore through the paint previously:



I stripped the paint and started cutting off the mounting tabs this morning.



I taped the top so I could mark all over it; not certain of the approach we'd need to take. In the end I took a wedge off of the rear bottom edge of the cell, allowing the rear to move downward, elevated the front, and moved it toward the center of the car.

Here is how it will sit, compared to an unmodified version:







This is why that is important: the 110l tank (shown here installed in the project car) sits much closer to the shelf - we need to be even closer to put the fills into the cell - we have to get around the perimeter screws and fill plate bolts!



A lot of high-level math (not really) later, and we are certain this will all work.




keith.

(sent from my rotary dial phone.)

[eimkeith]

Here is the mock up stuff; I'll be modifying one of our strut tower installation jigs to make the tooling for the hood through-holes.



(That's a correct early dry break, btw!)









keith.

(sent from my rotary dial phone.)

[eimkeith]

Thursday update:

Spent the day modifying our strut tower jig to fit around the 110l plastic tank, then made a bolt on sub-assembly to locate the holes on the hood accordingly.

Jig modified for clearance:



And with sub-assembly:



I'm now printing it pilot drill bit guide which will fit into the squares in the jig sub-assembly. This will allow me to drill a pilot hole from beneath, perpendicular to the horizon, centered on the fill hole positions.



That's a 12 hour print, so I'm back down to the shop floor to final fit the hood and fenders at the leading edges, so that I will be prepared to drill the pilot holes tomorrow.

I still need to determine the hole size for the fill openings; the splash/rain pans around the dry breaks are 150mm ID (scaled some photos) - but the hood holes appear to be smaller in diameter...


keith.

(sent from my rotary dial phone.)

[eimkeith]

A couple of quick shots from this morning to illustrate what I'm after with the jig; here is the pilot guide set up to drill the pilot hole in the hood for the right side fuel fill:





And yes, it is tight in the trunk with the hood closed!


keith.

(sent from my rotary dial phone.)

[empeg9000]

Amazing work!

[eimkeith]

Thanks!

Remember this issue with the reproduction right-hand fender?



Going after that this morning so I can finalize the hood gaps/position:




keith.

(sent from my rotary dial phone.)

[cnielsen]

Impressive work Keith!