Keith, I'm wondering what happens to the other side of a weld when you have no acces to it, like inside a cavity. Perhaps the drip rail you've removed is an example? Is the fresh metal surface inside a cavity, which is left uncovered of any protective primer, susceptible to rust sometime down the road?
Thanks for documenting this project so diligently.

Yes it is, insomuch as it is more or less bare metal at the weld and in the heat affected zone. Liberal use of a spray in rust converter and body cavity wax are better than nothing for areas like this (where the weld cannot easily be coated.)

Short of full e-coat of the chassis (which also can leave un-coated areas in overlapped panels, but is the best option available at the moment, to my knowledge) there are always going to be some un-coated metal areas - just as I suspect there were when the cars were assembled.

For this reason, I personally think it is best to limit the creative modification to cars that already have some 'life experience' - the pristine original cars, (although they are more than likely quietly rusting in their own seams and cavities to some extent) should be left unadulterated if possible.

On the other hand, not using these cars is a terrible idea - and even though the chassis is the longest-lasting part of the car, it is still a consumable in the end due to exposure to nature (thanks, chemical reaction.)

Anyway, for practical purposes, I don't foresee this owner having issues with the drip rail welding down the road - at least no more than the naturally occurring corrosion that we find between panels and in seams due to the age and exposure of these vehicles.

I'd love to hear other opinions on this - there are folks in this industry far more experienced than I am on such things!

Often when I see nice pics of well executed cutting and welding as I have on this thread, I wonder, and I have noticed others raise this question too, just what happens on the other side of the weld. Like you say, consideration of this will influence how to best attack the problem. It would be nice to know there's longevity on the other side of all that effort in fixing and modifying these cars.

Insightful...thanks for going to the trouble of answering.

For steel to rust, it needs water and air. If no water can get into the cavity, it will be fine for longer than the rest of the car that gets exposed to water on a "regular" basis.

Humidity notwithstanding, of course. ;)


keith.

(sent from my rotary dial phone.)

Productive morning!

I'm knee deep in the engine compartment backdating, 8 holes closed and the fuel filter assembly located and mocked up by lunchtime.

http://images.tapatalk-cdn.com/15/06...b88015ac67.jpg

http://images.tapatalk-cdn.com/15/06...542daa0048.jpg

http://images.tapatalk-cdn.com/15/06...75765c3107.jpg

http://images.tapatalk-cdn.com/15/06...df74054f82.jpg

I'll be looking at the relay panel modifications and mounting this afternoon, and will start putting together a plan for a clutch hydraulic reservoir (which I'd like to not be seen, and be visually historically plausible if possible.)


keith.

(sent from my rotary dial phone.)

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

Here's where we're going with the clutch reservoir:

http://images.tapatalk-cdn.com/15/06...264fa95426.jpg

That's the brake reservoir on a SWB 911; incidentally the same part number as the smaller of the two RSR brake fluid bottles, so it's perfectly era-appropriate!

And the factory mounting location is great for our needs also - low key, and virtually invisible (but accessible) when the fuel lines are routed over it to the dual RSR fuel pumps.

Here's our mounting solution:

http://images.tapatalk-cdn.com/15/06...810c4d55c8.jpg

http://images.tapatalk-cdn.com/15/06...80118fd46e.jpg

I'm now mocking up the front crossmember, steering rack, and pedal cluster - I need to finalize the clutch master cylinder solution before I wrap up this area.
I'm hoping for an elegant end result (I changed up the previous plan as a result of this clutch reservoir setup, which I really like.)


keith.

(sent from my rotary dial phone.)

And here's where we're putting the master cylinder:

http://images.tapatalk-cdn.com/15/07...9fc911a11e.jpg

I'm extending the RSR floor recess and creating a position for the clutch master to mount with the linkage in the tunnel. Here's the cabin-side view of the extension.

http://images.tapatalk-cdn.com/15/07...d77e01fbc8.jpg

I like this solution; it should be virtually invisible from both the cabin view and trunk view - excellent.

Crossing my fingers for an equivalent solution to the G50 shifter problem!

Have a happy 4th, will be back on Monday.


keith.

(sent from my rotary dial phone.)

I trust everyone got away from the grind for at least a day over the 4th of July weekend?

I got 2!

But now I'm back and put some work into something I was thinking about offhandedly over the holiday.

As this project has changed to become a more authentic visual representation of the R7 chassis, many components have changed accordingly (such as the handsome MFI bits on the engine, for instance.) Originally this car was to run a combination of Elephant and Smart Racing suspension, including the Elephant ASP system and Fox shocks. As the project has progressed, those parts have become inappropriate (as remarkably good as they are) and are being replaced with RSR Bilstein bits and factory spring plates.

A couple of years ago, I had the great fortune of getting my hands on a set of Chuck's 'Sphericals' for the A arms on my '72, and have been delighted with them; virtually no stiction, self lubricating, and maintenance-free (magic German composite bushings.)
Since then, I've been waiting for a version for the spring plates to install in the rear.

Rebel Racing also has their own version of the Elephant front Sphericals, also handsome, and they also offer a spring plate bushing solution that uses the same type bushing. I ordered a set for our Mary Stuart project.

The R7 chassis actually uses stock spring plate bushing covers and non-adjustable spring plates from the era, but apparently a Motorsport version was homolgated for the then-upcoming '74 season.
The Rebel parts loosely reference the look of those RSR Spring Plate bushing assemblies, but have a modern look which is unfortunate for this project.

Over the break I thought about how I could make the Rebel kit a little more visually appropriate, and got to work on it when I hit the office this morning.

Using photo reference from Armando's excellent RSR photo reference site once again, I dimensioned some printed photos and modeled a more visually correct RSR Spring Plate Bushing 'cover' to use with the Rebel kit (I'll substitute our outer cover for theirs.)

http://images.tapatalk-cdn.com/15/07...45bbeb3ddf.jpg

I'm also making the 3-bolt cap, so that we can knock the ends out of the factory spring plates and quick-change the torsion bar settings (not necessary for this project, but will be great on my car!). ;)

The printer is making a sample this evening while I'm typing this; I'll post that tomorrow.


After I got the printer going, I went back down to the shop and worked on getting the clutch master cylinder mounted and the linkage worked out:

http://images.tapatalk-cdn.com/15/07...cdc9504d79.jpg

That's the direction we're headed - actuating the master cylinder by pushing from the pull lever in the tunnel.

So far so good!


keith.

(sent from my rotary dial phone.)

I removed all of the clutter in the tunnel today (unused lines and tubing that might get in the way of the clutch hydraulic stuff and new routing) - that was interesting; working through the little access holes along its length - and started working on the hydraulic lines. I'll need to add one hole at the front end of the tunnel and we'll be set!

I also finished version 1 of the RSR cover plate for the Rebel Racing Spring Plate Bushing kit; then started on a revision. This part is proving difficult to dimension off of the photos that are available (close up photos have great detail, but distort the shapes)

Any possibility someone you know has one of these we can take measurements from?

No? Thought I'd ask, just in case.

http://images.tapatalk-cdn.com/15/07...caffd6e162.jpg

http://images.tapatalk-cdn.com/15/07...591b917692.jpg

http://images.tapatalk-cdn.com/15/07...3151a99c35.jpg

Getting there - it's going to be pretty cool.


keith.

(sent from my rotary dial phone.)

what an advancement in fab'ing anything with that printer... AND your design skills too...!! awesome keith...keep up the great work...bob

Thanks, Bob!


keith.

(sent from my rotary dial phone.)

Those are going to be pretty cool when done. Will be following with interest. Any plans to go into production when complete?

subscribe. Fantastic work!!!

Thanks guys!

I think I've got this thing sorted, design-wise, now. (Yesterday's effort didn't feel like a cast part; I put the hurt on my machine with the variable fillets today)

http://images.tapatalk-cdn.com/15/07...07df7be13f.jpg

http://images.tapatalk-cdn.com/15/07...25eee26a4a.jpg

Back to the sheet metal work tomorrow (if tonight's print lives up to expectation.)



keith.

(sent from my rotary dial phone.)

Looking good!

http://images.tapatalk-cdn.com/15/07...c7fa42cebf.jpg

http://images.tapatalk-cdn.com/15/07...c3abf2615f.jpg


keith.

(sent from my rotary dial phone.)

very nice... looks like a possible pricey pc to have machined out of alum i presume...??
thanks for your continued sharing of this I dare say "historic" build... obvious attention to detail is just as the porsche factory would do such...)) carry on...

My pleasure! And yeah, pricey to mill after all of the work on the fillets to make them look like older casting.

Did one more revision today of both the base and cap to try to finalize the proportions, and set up the printer to run this evening, then got back on the metal work.

In the process of prepping the roof right now:

http://images.tapatalk-cdn.com/15/07...9d52e97340.jpg


keith.

(sent from my rotary dial phone.)

Looks great - love the pics and the progress. Thanks for taking the time to document.

Question on the roof swap - thinking of doing the same with my sunroof. Do these swaps turn out structurally sound as the original? What are the best points to cut (where you did?)

Thanks -

Don't cut anything yet!

(I'll show you over the weekend) ;)