Screw selection for locker hinges?

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ash2020

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I have a bit of a conundrum here. Replacing the cockpit locker lids, I'm using the old solid brass piano hinges which are in very nice condition. I have solid brass screws to go into the wood of the lids but the other side is going straight into the GRP lip of the locker and ideally I need self-tappers as the brass screws are wood screws with a shank and I think would shear going into GRP.
I wouldn't normally like to use stainless up against brass but it looks like I have no option here. Would BZP screws be better? Zinc is nearer to brass on the nobility thingy. Any ideas please?
 
ash2020 said:
I think, on balance, you're right, even though stainless 304 is almost at the opposite end of the nobility table.
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There is about 0.3 volts between them but that is almost the same as between copper and 304 stainless steel, widely used in combination on standing rigging without serious problems.

Might be more problematic if your hinges were immersed (although millions of propellers on shafts survive OK) but on deck little to worry about.
 
ean_p said:
Or use brass csk set screws with brass nut and washer on the back.
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Csk machine screws they will be called.

But rather than self tappers screwed into the grp I was wondering if machine screws into tapped holes would be better.
I'd screw them in with a dab of epoxy on the threads. If the screws are not cleaned the epoxy won't adhere to them and it will always be possible to unscrew them if necessary. (I use Rapid Araldite if I screw self tappers into the grp. It's the only time I ever use the rapid stuff)
 
Personally use a dab of CT1 to help the stainless self tappers stay tight in the hole in my rather thin glassfibre of both my locker and doors/ lids.
Especially when replacing a loose screw with a slightly larger one.
 
ean_p said:
Only if he's one of our colonial cousins....... otherwise set screws fine ?
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Set screws have hex heads . They are like a bolt only fully threaded.
Maybe our "colonial cousins" call them something different
 
VicS said:
Set screws have hex heads . They are like a bolt only fully threaded.
Maybe our "colonial cousins" call them something different
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A set screw has a hex (most common) or straight driver, no head, and is used to secure shafts.
McMaster-Carr

A machine screw with an internal hex driver and a head is a socket cap screw.
McMaster-Carr

The brass screws will work if you pre-trhead the holes with self tappers of matching pitch and drill the hole the correct size. A drop of epoxy will make sure. But I'd use SS.
 
VicS said:
Set screws have hex heads . They are like a bolt only fully threaded.
Maybe our "colonial cousins" call them something different
Click to expand...
Don't know if this will work ......

<iframe src="Nettlefolds Screw Dept. : catalogue 1936. : Guest, Keen & Nettlefolds Ltd. : Free Download, Borrow, and Streaming : Internet Archive" width="560" height="384" frameborder="0" webkitallowfullscreen="true" mozallowfullscreen="true" allowfullscreen></iframe>

It should be a copy of GKN's catalogue of 1936 wherein on page 195 (222 of the reproduction) you'll see a list of set screws with various heads etc. Machine screws are also found within again with various heads but my understanding ( from 47 years ago) was that a M s had cut threads and a S s had rolled/ pressed or cast threads. But hay ho ?
As to our colonial cousins, our Lock and Spindle screws of yester year are to you your Set screws. Im not sure we use the terms any longer other then for the headless ones we know as grub screws.....!
 
ean_p said:
Only if he's one of our colonial cousins....... otherwise set screws fine
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I Googled set screws as it's a term I rarely hear used. I found 12 different types of set screws, the most common appeared to be what I would call a grub screw.
A screw cuts it's thread when inserted, a machine screw needs a thread to screw in to.
 
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Rappey said:
I Googled set screws as it's a term I rarely hear used. I found 12 different types of set screws, the most common appeared to be what I would call a grub screw.
A machine screw is not the same as a set screw.
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Your Captain America and I claim my £5?
 
In the US grub screw is on of those weird Britshisms, like spanner for wrench, or Mole wrench for Vice Grip (both of these latter are trademarks, Vice Grip by the Irwin Tool Company being the ealier of the two by a few years). But I understand what you mean.
 
thinwater said:
In the US grub screw is on of those weird Britshisms, like spanner for wrench, or Mole wrench for Vice Grip (both of these latter are trademarks, Vice Grip by the Irwin Tool Company being the ealier of the two by a few years). But I understand what you mean.
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Yes a 'grub' screw looks like a grub........simples ?
As for 'wrench', I don't know why but the name somehow seems to suggest that it should be adjustable in some way.....ie pipe wrench and the like...!
 
I can now understand why there is so much confusion over what a type of fixing is called.
I found the 12 types of set screws on rs components Web site. Now I've looked at many more .Co. uk Web sites and they all seem to have different names and definitions of a said fixing. ?
 
ean_p said:
Yes a 'grub' screw looks like a grub........simples ?
As for 'wrench', I don't know why but the name somehow seems to suggest that it should be adjustable in some way.....ie pipe wrench and the like...!
Click to expand...

If I read the OED, to wrench is to turn something, nothing more. So in the US they are all named as variations. If you ask for a 5/8-inch wrench, the default assumption is you meant a box end wrench if you did not specify.
  • Box end wrench
  • Open end wrench. Crows foot is a bent version.
  • Allen wrench (AKA hex key)
  • Socket wrench.
  • Pipe wrench (also strap wrench, Stilson wrench, and chain wrench)
  • And sometimes spanner. But this means a wrench that has to "span" between a pair of indentations, such as a pin spanner. AKA pin wrench.
adjustable pin spanner or pin wrench.
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Of course you still get plenty that don't know the name of parts or tools, in any language, and expect you to guess.
 
So much for a common language huh...?

Box end wrench. Box or Tube spanner (as in a length of pipe formed into an hexagon at either end)
Open end wrench. Crows foot is a bent version. Close (but both still spanners!)
Allen wrench (AKA hex key). Allen key (never a wrench)
Socket wrench. Socket spanner, a spanner with a fixed or swiveling socket at either end. Or if interchangeable then just a socket, moved with a bar or a ratchet.
Pipe wrench (also strap wrench, Stilson wrench, and chain wrench). Generally the same for pipe and strap except....Stilsons or a pair of Stilsons, but never a wrench!
And sometimes spanner. But this means a wrench that has to "span" between a pair of indentations, such as a pin spanner. AKA pin wrench. As in pin spanner and C spanner, again neither (pronounced nai ther....) ever a wrench! ?
 
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