Aurelia self tapping screws

[chriswgawne]

Its raining here this week which is great for our vines and fruit trees but a bit of a dampener for my car jobs.
But it gives me time to put a small but puzzling topic up on the forum.

When I restored our 4th series B20 for the first time in the late 70's, I had it painted old English cream - a colour we really liked - and I refitted the interior with new cross headed self tappers.
I proudly took the car to a LMC AGM and was frimly but pleasantly told that it wasn't a Lancia colour and that all the self tappers were incorrect. Somewhat deflated, I packed the car away, the paint deteriorated and in the very early 90's the car was stripped and repainted Lancia beige (which I was told was the original colour at the time by a so called Aurelia specialist workshop who did the bodywork - it wasn't! The original colour was amaranto) and all of the interior self tappers were replaced with chrome, countersunk slot headed screws which had a slight domed head. These were correct.

And every other B20 & B24 I have worked on has the same style self tappers.

When we bought our B12 Saloon a few years ago, I was very pleased that it was very complete and original with no new metal albeit that it had been painted and retrimmed. Its the one and only time I have bought an old car which didn't need major works and quite naturally I suppose, I began to try to find fault with the car as it seemed to good to be true....and also I probably wanted to do some work on it to give me confidence in its reliability going forward.
Then I noticed the interior trims screws - they were almost all cross headed! A B12 is effectively a '4th series B20 saloon' and we have owned several 4th series B20s, early and late. So I believed that my car had incorrect screws and I decided to replace them all over Easter this year.
Then I came across a B12 locally here in NE Italy parked - I had a look inside and it has cross headed screws!
I then contacted Brian Long in Australia whose car is very original in the sense that he has re-used all original screws and fitting in his restoration and I also contacted Ade Rudler whose beautiful B12 has been resored very wel, again using all original fittings.
And lo and behold their cars have 100% cross headed, chrome, domed head countersunk screws.
So all I have had to do is replace 6 in our B12, 4 were slotted and 2 were a little rusty.
But why were B20s of the same year different to B12s?
We will never know I imagine.
Little things and all that.
Its nearly stopped raining now.
Chris

[GG]

The "slotted screw" problem. Very hard to find the original ones.

Here's a suggested possibility. Start with the earlier cars and they typically used slotted screws. The cross-cut ones (we call them Philips-head screws) came on the scene in the mid-1950s, say 1953-54, and because of their increased production efficiency (less time loss to install) they were adopted by the factory in the factory's B12. PF was still hand making the cars with smaller production runs, with a smaller and likely better-trained labor force, stayed with what they knew and had used before.

Not 100% sure about this, but it suggests an answer. 

[Flamfan]

An early Flaminia PF road test observed that
' It seems to have become a regrettable trend in coachbuilt cars to prove their handiwork by having more exposed
screwheads than mass produced models, and the Flaminia Coupe abounds with them '.
My 1960 PF exhibits a plethora of non chrome Phillps head screws on the dashboard and elsewhere - not exactly elegant.
Not sure what screw type your Aurelia left the factory with but this Aurelia has turned a standard non Phillips screw into an art form.

[Niels Jonassen]

Geoff's explanation sounds very plausible.

[stanley sweet]

That's a beautiful interior and it's been done properly - the screw slots line up with the direction of trim.

[Sebastien]

On the spider picture, those are Durable Dot fasteners, certainly for a custom made tonneau cover, under the 3 screws for the top dashboard padding.
Nicely done and a good idea but not original, and a bit obtrusive.

Here another nice spider for reference (Registro Aurelia at Padova 2015). However I cannot check if the screw slots have been aligned :-)

Next subject: type of cup washers used by Lancia?