Hole in the Roof

Had the '38 SS out for a little drive last night. This morning noticed a hole in the roof, right hand side above the B post. I guess there was plastic body filler in there which popped off.

Investigating, there was something inside there.
Reaching in under the headlining, I could move it around. Managed to get it out.

Thin hex nut filled with Bondo.

Cleaned it out, trying to identify the thread.
Too large for 3/8-20 BSF or 3/8-18 UNC but too small for 7/16. Not M10x1.50 too small, nor M12x1.50 too large, though the pitch seems right. Might be 11mm x 1.50 which is in Machinery’s Handbook but not in French or German thread lists. Who would use 11mm?
The hole is 15/32" or 12mm, drilled through the inner brace of the B post.
So what was on the roof?

I was convinced that you were going to find a slug in there Rob!

Peter :wink:

p.s. Is there evidence on the other side of the car? Roof rack??

Nothing on the other side, though I suppose there could be one covered by Bondo. This car was repainted probably in the 1960s so whatever the hole was for dates from before that period when the car was black or before that ivory.

Are you going to put it back in so you have a quick answer to the nut behind the wheel joke?

Had enough trouble getting it out.
Is there a joke about the nut above the driver’s head?

I only know the one about the nut behind the steering wheel…:grimacing:

I would guess it had a small dome shaped lamp as used on some European cars of the time.

The roof lamps fitted in the UK that I’ve seen tend to be more in the centre of the roof with adjusting handles inside and not in the side area. Here is one on a 1948 Triumph.

Could be for roof tent fixing - something that was an interesting concept but didn’t sell well in the UK.


Curiosity got me, so I removed the left hand sunroof trim wood and pulled down the headliner there, so I could see and feel in there.
No hole in the left side at all.
So just on the right side.
Could it have been a spot light or something operated by the driver with his hand out the window?
Police siren?
Taxicab For Hire sign?
Not a roof rack or tent anyway. I’ve seen one of those roof tents on a Land Rover at the Chicago British Car Festival. But the Landie people love all those attachments. :laughing:

Could it be for an aerial for a radio? My 1948 MK IV has something similar through the roof - with the control of the position of the antena made by a handle inside above the driver on the roof liner (next to the wood trim of the sun roof). It was fixed from behind by a large nut, with a coax type cable running under the roof line material. Perhaps if not an aerial controlled from inside you could put your hand through the window and grab hold of a static version and twist its position to tune into your favourite radio station. I guess that radio reception was so poor in those days you had to keep adjusting the aerial to pick up a signal when you drove along.

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Is this the type of fixing nut left behind in your roof hole?
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On mine I took off the bakalite handle and unscrewed the aerial off the roof before going inside to release the roof liner and retrieve the nut and coax cable. Perhaps someone left yours behind and simply plastered over the top of it !!

i vote for ski rack !!


David, an interesting idea, but:

  1. there is no hole in the headliner
  2. there is no evidence the car ever had a radio
  3. if there was ever any wiring up the B post to the hole, it has since been removed

But that hex nut was in there, as if there was a threaded shaft, so somebody removed it but could not remove the nut, so they bondoed over it.

Ski rack? Is there that much skiing in Chiswick and Peterborough? :skier:
Water skiing on the Thames? :speedboat:
Surfin’ the Serpentine :surfing_man:t2:

Perhaps then you can discount anything electrical if there are no signs of cables, or anything heavy on the roof if there is only one fixing point discovered. Here is a WW2 gas conversion that might float more on the roof and only need one fixing!!

David, That’s a very interesting suggestion. So the fixings for the gas bag are all external and the hole in the roof is the inlet for the gas supply? I could almost believe it but my little grey cells tell me that the hole, she should be on the other side of le voiture where les carburettors reside.


Gas supply from the bag goes in at the back (near the fuel filler) - air vent above driver to stop them being gased and overcome by fumes!!

Oui d’accord mon ami.