Settled - Side Valences are affixed with plastic button head rivets, 'Rocker panel' rivets Options

[Craigers17]

I know the is a complete CW thing, & wasn't my intention to (IMG:style_emoticons/default/stirthepot.gif)
But I recall restoring my car & going down this rabbit hole.
The bad thing about the alum. pop rivets is they actually enlarge the fastening holes over time via rust from galvanic corrosion.
I had to weld & re-drill several so I could use/fit the correct fasteners.
(IMG:style_emoticons/default/smile.gif)

... (IMG:style_emoticons/default/stirthepot.gif) ....Heaven forbid we have to use aluminum pop rivets over plastic......really changes the whole vibe of the car (IMG:style_emoticons/default/rolleyes.gif) I mean....is this really a concern? In the words of the great Gene Simmons....this seems like a lot of "mindless minutiae". (IMG:style_emoticons/default/hide.gif)

[Montreal914]

...which leads me to ask. (IMG:style_emoticons/default/smile.gif)

What should be the hole diameter?

[davep]

I am a bit surprised by the heated discussion. Back in 1975 when I bought the first of my 914's I never saw aluminum pop rivets used on the rockers. That would have required a drill to remove the rockers again; NOT the factory way of doing things. I also have my paper parts manual for the 1970's along with the service manual set, the Technical bulletins, Flat rate manual, and the paint & interiors book.
Plastic rivets for certain!

[914werke]

"this seems like a lot of mindless minutiae".
I mean....is this really a concern?

One thing Ive never been accused of is being mindless. (IMG:style_emoticons/default/dry.gif)
Perhaps if you owned one of a small group of historically significant cars...you might have a different perspective. (IMG:style_emoticons/default/popcorn[1].gif)

[wonkipop]

"this seems like a lot of mindless minutiae".
I mean....is this really a concern?

One thing Ive never been accused of is being mindless. (IMG:style_emoticons/default/dry.gif)
Perhaps if you owned one of a small group of historically significant cars...you might have a different perspective. (IMG:style_emoticons/default/popcorn[1].gif)

i'm with you. i don't find minutiae mindless. (IMG:style_emoticons/default/biggrin.gif)

whoever brought up galvanic reaction is correct.
of course.
the factory was right using plastic.

i have found this particular discussion very useful.
i'm fully satisfied mine should have plastic rivets thanks to @Van B .

i intend to correct the mistake i made 30 years ago - that i will happily admit was mindless. (IMG:style_emoticons/default/biggrin.gif)

as well as having been mindless i am obviously losing my memory too.
since i cannot remember what was there 30+ years ago. (IMG:style_emoticons/default/beerchug.gif)

[Van B]

With galvanic corrosion, aluminum will lose out over low carbon steel. That’s why bolts going into aluminum engines are zinc plated. Zinc acts as the sacrificial anode giving up its electrons more easily.

Hole diameter is 3.4mm for both threshold and rocker. I just measured for you @Montreal914

[Montreal914]

Thanks Van B! (IMG:style_emoticons/default/smile.gif)

[930cabman]

I have used aluminum with success and I'm sure over time they will fail but is it a big deal?

Mcmaster Carr has plastic rivets, but not 1/8", does anyone have a source for a 1/8" plastic (pop rivet)?

[r_towle]

I used to read a lot of threads on the 356 forums, back in the day, and chuckle.

Well, we seem to have arrived.

Who cares? These pieces should have all been removed by now anyways.

Rich

[zoomCat]

I have used aluminum with success and I'm sure over time they will fail but is it a big deal?

Mcmaster Carr has plastic rivets, but not 1/8", does anyone have a source for a 1/8" plastic (pop rivet)?

914rubber has them in clear and black. Of course.

[Front yard mechanic]

Gee I thought liquid nails and duct tape was original. Learnt sumtin new everyday

[nivekdodge]

Are there any current members or people sitting on top of a mountain, who actually worked for Karmann or Porsche in the 70's

Kevin

[DBF]

Hate to beat a dead horse, BUT - why are there so many 74's with aluminum rivets? If so many people were taking off the side valances, shouldn't we also be seeing some cars with sheet metal screws holding the valances? It would have been a lot easier to use screws and people weren't as concerned about keeping the cars original back in the day? Couldn't the factory have simply used some aluminum rivets at some point when they were running low on plastic rivets, maybe the supplier shipped the wrong rivets to the factory, or the guy bringing the cases of rivets from the warehouse to that part of the factory occasionally grabbing the wrong case of rivets?

[Van B]

My car had painted pop rivets in the rockers and plastic push pin rivets in the plastic thresholds. I don’t think the rivets were aluminum. Chips looked like steel and I definitely was not drilling into the rocker. Also I was definitely the first person to remove them. I could even tell by the ziebart spray patterns that they used a hose to get in there vs remove/reinstall. Had I known this was still a point of curiosity, I would’ve confirmed the rivet details.

[wonkipop]

My car had painted pop rivets in the rockers and plastic push pin rivets in the plastic thresholds. I don’t think the rivets were aluminum. Chips looked like steel and I definitely was not drilling into the rocker. Also I was definitely the first person to remove them. I could even tell by the ziebart spray patterns that they used a hose to get in there vs remove/reinstall. Had I known this was still a point of curiosity, I would’ve confirmed the rivet details.

oh O.

i was going off your earlier statement the 74 rockers were plastic rivets! (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif)

yeah mine still has the black plastic rivets in the threshold plates.

looks like we got a question mark on 74 rocker rivets again?
oh no, i am risking mindlessness. (IMG:style_emoticons/default/biggrin.gif)



how do you know you were the first person to remove the rockers Van.
is that something you can be 100% about for some reason.
they still might have been off sometime between that original zeibarting and today half a century later.

[Van B]

The ziebart runs across the underside of the sill and the rocker… pulls apart like a freshness seal, except there’s nothing fresh under there…

[wonkipop]

The ziebart runs across the underside of the sill and the rocker… pulls apart like a freshness seal, except there’s nothing fresh under there…

ok forensic evidence is good. (IMG:style_emoticons/default/beerchug.gif)

looks like we could be back where we were.
the 74s are (at min) the exception to the rule of plastic rivets in the sill?
plenty of evidence out there of BAT archive cars. hard to know for sure.

and that S. G. car in the originality section sure was an exceptional car.
and as S. G. notes when he got it, metal rivets in sill rockers.
only black plastic now on advice of dr. 914.

then there is the hawaii bumble bee. with its metal rivets.

so................. (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif)
where is my mind. where is my mind. out there........ (IMG:style_emoticons/default/biggrin.gif)

[Van B]

I’m honestly not sure what the debate is here since this thread appears to start mid debate. I have black plastic thresholds with black plastic push pin rivets and (had) rocker panels with black metal rivets.

All holes appear ~3.4mm. I measured six of them on both sides of the car.

[JeffBowlsby]

Anyone who knows anything about these cars removes the side valances to clean and inspect, at least at the time of purchase. 50 years later it’s highly likely that the valences have been removed at least several times, if not more on every car. The few original owners here tell us these rivets were plastic, not alum. George is an authority on these cars, more than anyone else I can think of, and he confirms. Alum rivets or even sheet metal screws are always commonly available and convenient at the local hardware store, only the purists would bother to get the correct plastic rivets from the dealer. The 74s were not special in this detail, it is illogical that this would be a 1 year change. That’s the best rationalization I can think of.

[rgalla9146]

Anyone who knows anything about these cars removes the side valances to clean and inspect, at least at the time of purchase. 50 years later it’s highly likely that the valences have been removed at least several times, if not more on every car. The few original owners here tell us these rivets were plastic, not alum. George is an authority on these cars, more than anyone else I can think of, and he confirms. Alum rivets or even sheet metal screws are always commonly available and convenient at the local hardware store, only the purists would bother to get the correct plastic rivets from the dealer. The 74s were not special in this detail, it is illogical that this would be a 1 year change. That’s the best rationalization I can think of.

Amen (IMG:style_emoticons/default/beerchug.gif)