Tool name needed

[Tinbasherdan]

Random one but I know we have some tool geeks here. Trying to identify/ find a type of screwdriver used on slotted aircraft screws around ww2. It’s like a reverse security but in that the blade has a pin in the centre which locates in a corresponding dimple in the screw to stop it slipping (I believe a throwback to fabric aircraft covering days)

Anyone got any ideas?

 

[Barking Mat]

Bob.

No, can't help, photos of fastener would help.

 

[Tinbasherdan]

I should have expected that

 

[Barking Mat]

I should have expected that

You've been on this forum ten years, you know what we're like.

Apologies.

 

[cheb]

Clutch head? Not the cam out types, there's another one.

 

[BarrieJ]

I'd hazard a guess, these people would know, they could probably supply the fasteners and the tool.

Vintage Fasteners - JP Aero Ltd

Large stocks of vintage fasteners and historic heritage fasteners and in-house sourcing experts for early aircraft types. Over 50 years’ experience.

jpaerocom.co.uk

 

[Merkava_4]

DZUS FASTENERS

 

[Robert Weaver]

Spanner bit ?

 

[gaz1]

theres another reference to those type of screws

they was a flat head that also used a screw cap on them usually domed

Chrome Dome Head Mirror Screws

Chrome Dome Head Mirror Screws from a leading glass merchant. Buy all your glazing accessories in our online shop!

www.wholesaleglasscompany.co.uk

 

[Tinbasherdan]

Spanner bit ?
View attachment 399181

It’s the direct opposite of that, the blade has a central pin rather than a slot

 

[cardiffrob]

Dome head, but shallow, with a small depression down into the bottom of the slot? The hole is to centre it if it has to be drilled out? Shackleton access panel screw, perhaps.

 

[cardiffrob]

AS1248?

 

[Tinbasherdan]

Dome head, but shallow, with a small depression down into the bottom of the slot? The hole is to centre it if it has to be drilled out? Shackleton access panel screw, perhaps.

Same fastener but there is apparently a screwdriver that fits the depression to stop it slipping. They’re chipmunk cowl fasteners!

Edit- it may be that the driver was a homemade affair by an enterprising fitter, but there’s certainly been at least one spotted in the wild!

 

[Hitch]

I was going to say dsuz, but they dont have a pin, a sort of curved bottom slot instead.

 

[nickk]

Bob.

No, can't help, photos of fastener would help.

He’s Dan anyway,lol.

 

[Tinbasherdan]

I was going to say dsuz, but they dont have a pin, a sort of curved bottom slot instead.

Definitely not dzus, you use a “church key” for those!

 

[Moose McAlpine]

If you know the blade/pin dimensions i can modify a screwdriver/bit for you on the lathe.

 

[Agroshield]

If you know the blade/pin dimensions i can modify a screwdriver/bit for you on the lathe.

Draw a picture of what it looks like irrespective of dimensions. It will be extremely difficult to make on a lathe.

It would look like a transfer punch that has mated with a flat blade screwdriver.

 

[James1979]

I text a friend who is a helicopterist and he said “cow mouth”? But he will take a photo when he is next on shift if he remembers.

Asks if you can post a pic of the fastener please

 

[cardiffrob]

The flat blade can't apply torque at the very centre of the screw head slot so they drill it away to help with centring drill bits if it gets munched? I always used an old parallel-faced flat blade for those fittings rather than the more modern tapered blades, which seem to cam out more easily.

The licenced guys working on the Shackleton didn't have many of the right tools for dismantling one. They'd bring a mix of AF and Metric and wonder why the fit was so bad. Same with all the 2BA fittings inside.