screw head

[gary17]

Hey

Any way suggest the best way of removing this screw.

Do not want to drill it incase i destroy the thread.

Ain,t there some chemical i can use that will dissolve the screw but not the bridge?

 

cheers

gary

[Kraai]

 

 

 

[rodabod]

I use the “rust remover” solution from cousins. It’s pretty lethal. 
 

Did the screw have a left-handed thread?

[Nucejoe]

Bergeon tool must be nice to have, penetrating oil before any physical approach helps.

Alum disloves the screw and wont hurt the base metal.

[JohnR725]

As long as you remove all of the other steel component so you only have the plate then you can use alum mixed in water and that will dissolve out the screw. If you're in a rush you can warm up the solution It will dissolve it out faster.

[oldhippy]

I always used Alum. 

[clockboy]

I have the Bergeon tool "Kraai" shows via a video.  Expensive as always with Bergeon but works a treat. I have not had much success using Alum but I suspect it must be my method the only issue is the amount of time it takes. 

[oldhippy]

Alam takes time that is the downfall, but I had loads of other repairs to do so it didn't bother me. Good old Bergeon always ready to take your money.

[Pip]

I tried and failed with alum on a battery spring/retaining screw on a Seiko 7548. Several days and a very concentrated solution but the screw remained unimpressed by my efforts. As you can see, I may have got carried away with the strength of the solution, it became crystalline over a few days in the airing cupboard.

I have now ordered a Bergeon type tool. Where from? Well, let's just say that when it arrives it will be disinfected in case the person who packed it had a bat sandwich for his breakfast.

[luiazazrambo]

That is the only bergeon tool I ever bought as I thought it is a life saver. I used it twice so far, both times I brutally damaged the main plate. I still have nightmares.  However knowing about myself probably I was not careful enough and I had no experience or has no experience yet as how to use it properly. I seem to have difficulties to understand that you have to take your time when you deal with watch movements.

The crown shaped end of the tool could not get a good grip on the broken screw by the way and I made also a mistake not to use the proper sized tool originally and when I used the right size? it was already too late. Was too hasty etc. The watch i prepared as an xmass present for Mrs still has the broken screw and this thing never goes away... i must fix it sooner or later as it will haunt me forever.

Edited May 29, 2020 by luiazazrambo

[praezis]

9 minutes ago, Pip said:

I tried and failed with alum on a battery spring/retaining screw on a Seiko 7548. Several days and a very concentrated solution but the screw remained unimpressed by my efforts. As you can see, I may have got carried away with the strength of the solution, it became crystalline over a few days in the airing cupboard.

That most probably was a stainless steel screw. Modern screws often are SS.

Frank

[JohnD]

2 minutes ago, praezis said:

That most probably was a stainless steel screw. Modern screws often are SS.

Frank

And as stainless steel has a lower tensile strength than the corresponding carbon steel equivalent, makes it more likely to shear off......and while the stainless won't rust, damp can cause galvanic action where the brass plate it is screwed into can start to corrode....

[Pip]

32 minutes ago, luiazazrambo said:

That is the only bergeon tool I ever bought as I thought it is a life saver. I used it twice so far, both times I brutally damaged the main plate. I still have nightmares.  However knowing about myself probably I was not careful enough and I had no experience or has no experience yet as how to use it properly. I seem to have difficulties to understand that you have to take your time when you deal with watch movements.

The crown shaped end of the tool could not get a good grip on the broken screw by the way and I made also a mistake not to use the proper sized tool originally and when I used the right size? it was already too late. Was too hasty etc. The watch i prepared as an xmass present for Mrs still has the broken screw and this thing never goes away... i must fix it sooner or later as it will haunt me forever.

Gonna quote Luke in the Cantina here: "I'll be careful." I have a spare mainplate on the way so I'm covered if I balls it up but I'd rather get the screw out if I can.

 

25 minutes ago, praezis said:

That most probably was a stainless steel screw. Modern screws often are SS.

Frank

I guess you are right. I have a big bag of alum and not a lot to do with it. I could pickle some onions later in the year!

[nickelsilver]

That's 99.999% sure a left hand thread, I've found that screws are often rather loose in their threaded hole once the head breaks off, see if you can get a grip on it with strong tweezers and go righty-loosey. You can mimic the Bergeon tool somewhat using a staking tool to capture the screw by each end and turn the bridge to unscrew.

[oldhippy]

1 hour ago, Pip said:

I tried and failed with alum on a battery spring/retaining screw on a Seiko 7548. Several days and a very concentrated solution but the screw remained unimpressed by my efforts. As you can see, I may have got carried away with the strength of the solution, it became crystalline over a few days in the airing cupboard.

I have now ordered a Bergeon type tool. Where from? Well, let's just say that when it arrives it will be disinfected in case the person who packed it had a bat sandwich for his breakfast.

Don't you mean a tin of this?

[Nucejoe]

In this case, enough of the screw sticks out to grab with a nail clipper or needle nose pliers.

[luiazazrambo]

3 hours ago, nickelsilver said:

That's 99.999% sure a left hand thread, I've found that screws are often rather loose in their threaded hole once the head breaks off, see if you can get a grip on it with strong tweezers and go righty-loosey. You can mimic the Bergeon tool somewhat using a staking tool to capture the screw by each end and turn the bridge to unscrew.

I also managed to get out a screw similarly, used a bit of penetrating oil and with a lupe and with fine tweezers a managed to rotate the screw by the fraction of a mm by pushing the outer side of the screw as many times as it was required to be able to grab it at the end of the process. I guess it only works if the screw is not seized in its hole too much.

I also think that i am now in a better position with using the bergeon tool having a stereo microscope with ring light so I could actually see what I am doing instead of being blind and go with full speed.

Edited May 29, 2020 by luiazazrambo

[spectre6000]

1 hour ago, Nucejoe said:

In this case, enough of the screw sticks out to grab with a nail clipper or needle nose pliers.

Is there a reason a pin vise isn't in that list? First thing that came to my mind, but it's not something I've been faced with on this scale before.

Edited May 29, 2020 by spectre6000

[Nucejoe]

1 hour ago, spectre6000 said:

Is there a reason a pin vise isn't in that list? First thing that came to my mind, but it's not something I've been faced with on this scale before.

I usually end up trying every tool I think may work. 

[rodabod]

There’s also enough screw protruding there to cut a new slot. I’ve done that successfully several times before.