Help ! International Hardware Question: Metric Wood Screws ?

[De Soto Frank]

I beg the indulgence of the Forum moderators, but if anyone can answer my question, I'll bet they're on-board here.

I work for a performing arts center in NE Pennsylvania, which is housed in an historic Masonic Temple.

We have an inventory of wooden cafe chairs made between 1925 and 1930, by the Thonet Chair Co., local office in Brooklyn, NY at the time.

However, Thonet & Co. got their start in Germany in the 1880's, and our chairs have "Made in Czechoslowakia" [sic] stamped into the wooden frames.

( I am thinking the wood components and steel hardware were made in Europe, and shipped to their American branch PKD or CKD (partiailly / completely knocked-down), to save on Tariffs, and were assembled here in the US.)


So, I am in the process of repairing these chairs (several hunderd), which have lost some screws over the years. I've been trying to match them up to standard US sizes w/o luck. They are between #10 and #12 in diameter, and seem to hit on the 1/8th-inch for length, instead of ¼ & ½.

Google searches for "metric wood screws" haven't really turned-up anything useful.

The Hillman screw gauge at Ace Hardware suggests these screws would be:

4.5 mm x 30 mm
5 mm x 30 mm
5 mm x 40 mm
5.5 mm x 40 mm

Otherwise, they look like blued-steel, oval-head wood screws, common in cabinetry before WW II.

Can anyone recommend a screw supplier that would have these ?

( Even a screw-size chart for metric wood screws would be helpful, even if in German or French, so that I search by proper size... )


Or do European cabinet-makers all use US / Imperial sized wood screws ?


Help! this is driving me Screwy !

[startgroove]

McMaster Karr has huge selection of screws of all kinds. Cheers, Russie

[De Soto Frank]

Thanks Russie,

They were my first stop... lots of wood screws, but nothing in metric sizes...

I appreciate the suggestion though !


Regards,

Frank

[Uncle Vanya]

I had the same repair to make about forty years ago. I acquired about a thousand of those Thonet chairs from the cafeteria of the old Richman Brothers clothing factory. These were the early "balloon back" chairs with the exaggerated shape and the sun-Ray embossed seats, and the wire reenforcement. These chairs had been used in a cafeteria setting since 1915, and were rather wobbly. I made up curved washers (rather like half-ferrules) out of steel tubing for use in the ends of the up side hoops and drilled out the screw holes which fastened the rear legs and the hoop to the back of the seat and then ran oval head machine screws with washer, lock washer and nut in the inside. This repair was quick, fairly cheap, and greatly strengthened the chairs. I still have a dozen, which thirty years on are still stronger than they were in 1913.