Knurled screw

[280sl1968]

I have seen in parts listings a knurled screw that is described in German as "Rändelschraube Fondboden"

This seems to relate to something to do with the rear floor but I don't see anything like this on mine.

Any ideas where these are used?


Thanks

David

[66andBlue]

These thumb screws hold down the parcel shelf.
The one on the left has the correct shape for a 230SL but it should not be chromed. On the right has correct surface but wrong shape.

[mdsalemi]

Alfred,

Where do you suppose these incorrect (chroming, wrong shape) screws came from?  Curious if they might have had some other Mercedes use, or they are just random finds?

[66andBlue]

Michael,
the correctly shaped screw was on my 230SL but I just added it into the bucket with other small parts that needed re-schroming. Didn't know at the time that they should be more "matte" steel. In any case, I have no regrets because I do like bling in a 230SL.  
The generic ones are available in Germany from many hardware supply companies and lots of eBay vendors sell them.
However, we had a discussion a number of years ago and some owners claimed that the straight shaped bolts were actually used on 280SL models. Next time I am at Motoringinvestements I'll ask Brian what he has seen on original cars.
Addition:
The situation is actually a bit more murky.
The p/n for the thumb screw is: 000464 00600 = DIN 464 / Surface: DBL 8451-22 = "high polish galvanized, chrome-coloured passivation, can also be used instead of chromium-plating, if required".

As to the shape of DIN 464 what one finds now are almost always straight screws without concave indentations. This may be a manufacturing simplification or evolution of the DIN standard.
The sketch below shows the contour of current DIN 464 and the related DIN 465 and DIN 466 screws. Even the latter ones are now available mostly with straight cylinders.
The good news is that occasionally one can still find a DIN 464 screw with concave indentations; see:
http://www.ebay.de/itm/290918807685

[49er]

My parcel shelf screws match the right hand (straight shaft) shown in Alfred's photo and appear to be cad plated. Definetely not chrome.

John

[280sl1968]

The ones listed on ebay are described as a "faithful reproduction of steel and nickel-plated surface"

[280sl1968]

Interestingly Authentic Classics is selling these for the 230SL and says:

Parcel shelf Thumbscrew and Washer set.
 
Pair of Rear Parcel shelf Thumbscrews and Washers for early Mercedes 230SL Convertibles - 113 Chassis, these are only used on early cars that were not prepared for seat belts, later cars had larger 7/16-20 threaded holes for the seat belt attachment and the seat belt bolts also retained the parcel shelves.
 
Thumbscrews are Zinc Plated, Washers are stainless steel.

http://www.authenticclassics.com/early-230SL-Parcel-Panel-Thumbscrews-113ch-p/auth-002721.htm


So the 250SL and 280SL with seat belts didn't have these?

[Garry]

My '69 Euro  280Sl certainly had them and seat belts as well.

[66andBlue]

The information on this web site is incorrect, all W113 cars have the thumbscrews on the parcel shelf.
The 7/ 16" threaded hole mentioned there is below the thumbscrew on the wall as well as on the tunnel and the B-pillar and is used for 3-point seat belt attachment as detailed in the Mercedes installation instructions (see below). The thread for these holes was changed from 10 mm to 7/16" starting with 230SL VIN 006055.

[mdsalemi]

we had a discussion a number of years ago and some owners claimed that the straight shaped bolts were actually used on 280SL models.

I'll have to check mine today (I'm certain they are original to this car) and report back...