Authentic woodscrews?

[emeritus]

Philips machine screws were used in one of the televisions we had in the 1950's. I remember that dad bought a Steadfast ratchet screwdriver set that included a Philips bit to take it apart for repairing it. I remember asking him why that type of head was used and he said something about making you buy more screwdrivers! I later found out that the Philips head was designed to cam out under excessive torque, apparently advantageous for production line assembly using power screwdrivers, and the pointed configuration means the bit self-aligns with the screw's recess, meaning faster assembly. Conversely, the Pozidriv head is designed so that it does not cam out, possibly making it easier to undo?

A Canadian guy I used to work with once mentioned that he hadn't seen the square recessed head screws that they used back home. I have only ever seen examples of those screws here on stuff manufactured in North America, although the square bits are frequently found in sets of hex drive bits.

[barrymagrec]

Originally Posted by emeritus

A Canadian guy I used to work with once mentioned that he hadn't seen the square recessed head screws that they used back home. I have only ever seen examples of those screws here on stuff manufactured in North America, although the square bits are frequently found in sets of hex drive bits.

Robertson screws.

Robertson refused to licence their use to Henry Ford so they remained largely unknown outside Canada.

[Joe_Lorenz]

Properly restoring an old radio makes the use of original type of screws mandatory. A Pozidrive can just be a temporary substitute when the old slotted screw was bent or broken. Finding a good quality screw driver is not easy nowadays, so I prefer "Hazet" who have a good reputation for making mechanic's tools.

Joe

[G6Tanuki]

Regarding Robertson screws: my parents had a dining-room table and a sideboard that they got when they were married [1947?] which were 'Utility' furniture and was held together using Robertson screws. I suspect that there may have been a bunch of them kicking around in the UK as 'war surplus' at the time.

The table and sideboard were thrown out in the late-60s, with the coming of Habitat.

[wd40addict]

My Gecophones No2 crystal set arrived with slotted, but clearly modern shiny screws holding the front panel into the wooden case. Like the architectural references above it annoyed me every time I looked at it. Some patience was required and eventually eBay came up with something appropriate. In the meantime I looked in every ironmonger and boot sale I came across, but no joy there.

I've found that ironmongers have become very homogenised with the same stock everywhere.

[David G4EBT]

Originally Posted by barrymagrec

Robertson screws.

Robertson refused to licence their use to Henry Ford so they remained largely unknown outside Canada.

The patent ran out long ago - square drive screws are widely used in the UK, as are 'Torx' screws.
Unlike Philips and Posidrive, they don't 'cam out' when used with air tools or power tools.

Some examples of square drives from UK suppliers:

Self tappers:

https://www.accu.co.uk/square-drive-...EaAp34EALw_wcB

Wax coated stainless steel decking screws for use with pressure treated timber, such as Tanalised:

https://www.screwfix.com/p/deck-tite...B&gclsrc=aw.ds

Torx Drive screws are also commonplace:

https://www.toolstation.com/forgefas...B&gclsrc=aw.ds

This explains why the Torx drive design is superior to 'Robertsons':

https://pedriana.wordpress.com/2021/...0first%20place

Four our purposes, with radio cabinets and the like I guess we're most likely to need smaller sized slotted brass countersunk and round head slotted screws - No 4, No 6, & No 8, from 3/8" long upwards. They're available, but finding them in small quantities can be a challenge. This supplier can supply a wide range of RH and CS small brass screws, but in boxes of 200. The unit price is fine - EG 200 No 4 x 1/2" (3mm x 12mm) £9.36 inc VAT, so under 5p each, but if you only need ten, what are you going to do with the other 190?

https://screwshop.co.uk/brass-slotte...s-csk-head-p30

https://screwshop.co.uk/brass-slotte...round-head-p34

How we suffer for our art!

[David G4EBT]

Originally Posted by wd40addict

My Gecophones No2 crystal set arrived with slotted, but clearly modern shiny screws holding the front panel into the wooden case. Like the architectural references above it annoyed me every time I looked at it. Some patience was required and eventually eBay came up with something appropriate. In the meantime I looked in every ironmonger and boot sale I came across, but no joy there.

I've found that ironmongers have become very homogenised with the same stock everywhere.

Not sure what model my Ericsson crystal set is, but the C/S brass screws are 3/8 No 3 or 4 for the hinges, and what looks like 1/2" No 4 to fix the front panel. In spidery writing in the lid, evocative of an elderly owner, is pencilled the setting for 'Forces' and 'Home Service' which suggests that it was still in use during the early to mind 1940s.

Some pics of the screws attached.

Until the mid to late 60s, slotted screws were the norm in the UK, but with the advent of power drills, both corded and cordless, with variable speed, and torque settings intended for fitting screws, whether for DIY, joinery or site work, over time, cross point screws became the norm. (We know what happens if you try to drive slotted screws with a power tool - it rarely ends well).

It isn't just the heads that differ - the thread pattern of cross points differs markedly and is parallel - not tapered, so in many cases, no pilot is needed. DIY stores have long since stopped stocking slotted screws. I just googled B&Q 'Slotted Screws' out of curiosity. Response:

Quote:

"Sorry, we don’t have any "Slotted Screws" available at the moment. We’ve recommended some other products below".

End quote.

The 'recommended alternatives' were of course cross-points. (C/S yellow passivated steel).

I recently popped into the loo at a recently refurbished posh Notting Hill restaurant a couple of weeks ago. (Twin granddaughters 22nd birthdays). Expensive tiling, flooring, sanitary ware, taps, chrome pipework. The chrome pipe brackets, which were not countersunk, should have had chrome plated brass round-headed screws. Instead, they had zinc-plated steel countersunk with the heads stuck out. Complete eyesore.

There was a time when you could tell the difference between DIY work and those in the trade - not any more.

[Gridiron]

Robertson screws were used on some British early 1920's sets such as the GEC BC2000 smoker's cabinet, presumably to differentiate them from the screws to remove to separate the chassis from the cabinet (slot heads). Pye also used them on some sets.

[Ed_Dinning]

Hi Gents, I have lots of slotted head woodscrews in various styles. Japanned, chrome, brass etc in the smaller sizes.

Please mail me if you would like an assorted bag of , say 500gm, for little more than the postage.

Ed