What do you call gold colored screws on old pocket watches?

[Max50916]

So I recently serviced a 15 jewel Waltham Export grade 16s movement and it has these beautiful gold colored plate screws etc. What is the correct terminology for these? Would they be considered gilt? I know blued hands tend to be more common but I'm sure there must be a term for this color of finish. Thank you for any info you can provide!

[JohnR725]

unhelpful answer is its heat-treated. If you look at a heat treating chart there is a temperature range where you get a gold color and my understanding and that's what this is. I've seen a number of watches that do this. I even had an Elgin watch where all the screws of course were gold and the hairspring was gold. Which did give don't remember what but it did have some different timing characteristics because instead of being a blued steel spring it's a gold steel spring which of course is going to have different physical properties

then can't read your serial number but you might look on the pocket watch database and see if it says anything.

.

https://pocketwatchdatabase.com/

 

 

[RichardHarris123]

13 minutes ago, JohnR725 said:

unhelpful answer is its heat-treated. If you look at a heat treating chart there is a temperature range where you get a gold color and my understanding and that's what this is. I've seen a number of watches that do this. I even had an Elgin watch where all the screws of course were gold and the hairspring was gold. Which did give don't remember what but it did have some different timing characteristics because instead of being a blued steel spring it's a gold steel spring which of course is going to have different physical properties

then can't read your serial number but you might look on the pocket watch database and see if it says anything.

.

https://pocketwatchdatabase.com/

 

 

I thought the colours indicated the temperature not the final colour ?

[Neverenoughwatches]

1 hour ago, RichardHarris123 said:

I thought the colours indicated the temperature not the final colour ?

When tempering the steel it aquires a hue of colour. Different tones indicate a different level of temper. Wood chisels i used to harden to a cherry red quench in water then temper to a purple or blue maybe cant quite remember and then dip in sand or leave to air cool. I think , long time ago memory is fuzzy today. 

[Max50916]

3 hours ago, JohnR725 said:

unhelpful answer is its heat-treated. If you look at a heat treating chart there is a temperature range where you get a gold color and my understanding and that's what this is. I've seen a number of watches that do this. I even had an Elgin watch where all the screws of course were gold and the hairspring was gold. Which did give don't remember what but it did have some different timing characteristics because instead of being a blued steel spring it's a gold steel spring which of course is going to have different physical properties

then can't read your serial number but you might look on the pocket watch database and see if it says anything.

.

https://pocketwatchdatabase.com/

 

 

Ok this is very helpful thank you! Wow sounds like a very cool Elgin movement.

[mikepilk]

I've never seen that on pocket watch screws.

Tempering colour chart :

[RichardHarris123]

I still don't see how heat treatment alone gives a gold colour. 

1 minute ago, mikepilk said:

I've never seen that on pocket watch screws.

Tempering colour chart :

Isn't that the colour when still hot, not the final colour. 

[mikepilk]

1 minute ago, RichardHarris123 said:

I still don't see how heat treatment alone gives a gold colour. 

Exactly the same a "bluing" but to a lower temperature. (e.g. https://www.youtube.com/watch?v=AeISVhZxLm8 )

It's a thin oxide layer which causes the colour by interreference.

You need precise temp control to get a steady yellow - I've only blued.

[RichardHarris123]

7 minutes ago, mikepilk said:

Exactly the same a "bluing" but to a lower temperature. (e.g. https://www.youtube.com/watch?v=AeISVhZxLm8 )

It's a thin oxide layer which causes the colour by interreference.

You need precise temp control to get a steady yellow - I've only blued.

Does it have to be cooled at a specific rate? 

[mikepilk]

No, once it reaches the required temp, it's dipped in water to stop it changing. If you watch the youtube video, it's all nicely explained,

Edited March 9, 2023 by mikepilk

[JohnR725]

if you're doing screws today the easiest way is with some of the electric hot plates. you can dial an exact temperatures and get exact colors without going past. Unlike heating it up the traditional way if you're not careful you can easily go past where you need to be.

[oldhippy]

They look to be brass, what are the threads of the screws like. It would be near impossible to have every screw and every part of screw to be that same colour. They have never been heated.