How do you remove stuborn screws ?

[Chopin]

I sometimes have a hard time unscrewing movement screws and I have to admit that there have been screws that I just couldn't unscrew. Don't worry we're talking about practice watches here, nothing serious...

How do you guys remove stuborn screws ? Are there any special hints or techniques that I should know ? Do you use a small hammer and tap the screw or something like that ? Do you press down while unscrewing ?

I'd like to mention that, for now, I have cheap and crappy screwdrivers but I will swap them with french/swiss in the near future.

[SteveFitzwater]

there is no substitute for a quality screwdriver set in good condition, if I get a screw that gives me issues, first thing I do is either sharpen the bit, or put in a new bit. There is a tendency to keep trying, but your only going to make it harder on yourself, sharpen or change out the bit right off, and it will save you headaches

Also remember that there are left handed screws in watch work, they are normally marked with the 2 lines, one on either side of the screw slot.

[DouglasSkinner]

There's a lot of stuff out there on removing stubborn screws.  Depending on the movement and the screw's location I've used Liquid Wrench(tm) and also Kroil(tm) penetrating oil.  Under certain conditions alum will work but you have to be careful.  It goes without saying that you strip down the movement as far as possible and then make a determination whether these approaches will be safe. Attached is a PDF with some more ideas.  Hope this helps.

Broken_and_Rusted_Screws.pdf

Edited March 1, 2017 by DouglasSkinner

[DouglasSkinner]

I forgot to include two other documents that may also be helpful.

Remove a Broken Screw.pdf

Remove_Broken_and_Rusty_Screws.pdf

[Deggsie]

There's a lot of stuff out there on removing stubborn screws.  Depending on the movement and the screw's location I've used Liquid Wrench™ and also Kroil™ penetrating oil.  Under certain conditions alum will work but you have to be careful.  It goes without saying that you strip down the movement as far as possible and then make a determination whether these approaches will be safe. Attached is a PDF with some more ideas.  Hope this helps.
Broken_and_Rusted_Screws.pdf

I may be wrong but doesn't alum only work on ferrous screws in brass or stainless plates. The ferrous screw being the component which is sacrificed?


Sent from my iPhone using Tapatalk

[Geo]

8 hours ago, Deggsy said:

I may be wrong but doesn't alum only work on ferrous screws in brass or stainless plates. The ferrous screw being the component which is sacrificed?


Sent from my iPhone using Tapatalk

You are correct.

[anilv]

Usually I can remove the threaded part by using a sharp pick/needle and unscrewing it off. This is when the screw breaks because of weakness of screw or excess force used. When rust is present it won't work.

If the screw hole was threaded all the way thru the plate, you can screw it in an it will come out the other side.

I just fixed a Seiko 7s26 which wouldn't run. Turns out the LH screw on the reduction wheel was broken. Watch was worn daily and the screw just broke! The broken piece was wound out with a pick and a replacement screw fitted. Owner didn't see the need for a service so it back in harness! Gotta love Seikos!

Anilv

[SeikoWatch]

Thanks Douglas for the files .

[sstakoff]

I posted a while back about a particularly stubborn dial screw:

 

[DouglasSkinner]

On ‎3‎/‎2‎/‎2017 at 9:45 AM, Deggsy said:

I may be wrong but doesn't alum only work on ferrous screws in brass or stainless plates. The ferrous screw being the component which is sacrificed?


Sent from my iPhone using Tapatalk

You're right.  You have to be very judicious using it to make sure you don't do damage to other plates/parts; but it's good to have in one's **BLEEP**nal for those situations where it will work.

[vinn3]

the penitrating  oils  mentioned are the way to go and give them time to work,  i don't know why alum is used.  also, there are many posts on stuck screws on this forum - if you can find them.

[DouglasSkinner]

4 hours ago, vinn3 said:

the penitrating  oils  mentioned are the way to go and give them time to work,  i don't know why alum is used.  also, there are many posts on stuck screws on this forum - if you can find them.

Alum will actually dissolve an iron or steel screw in cases where penetrating oil doesn't work.  This is an aggressive treatment and care has be taken that you don't harm the plates or parts containing the screw.  One of my colleagues used it recently to remove a stubborn and broken screw; the plate was brass and came out unharmed.

[vinn3]

thanks,  have you tried it on dial screws?

[DouglasSkinner]

1 hour ago, vinn3 said:

thanks,  have you tried it on dial screws?

If you're talking about the alum treatment, the same considerations apply.  In a vintage watch it would certainly dissolve a steel dial screw as well as any other screw.  But again, it is most important to assess the possible impact elsewhere on the watch plate.  If there's a chance of damaging something in addition to getting rid of the screw, then I wouldn't do it.

[anilv]

Alum is the last resort if all else fails. You don't have to submerge the whole plate.. just make a paste and apply on the screw head. If the opposite end has a 'well' fill that up. 

Alum usually works best with hot water but that just accelerates the process. Room temp water just takes longer.

Anilv

Ps.I've come across people recommending mixing alum with Vaseline to make a paste ..never tried it but makes sense.

Edited March 5, 2017 by anilv

[Deggsie]

Alum will actually dissolve an iron or steel screw in cases where penetrating oil doesn't work.  This is an aggressive treatment and care has be taken that you don't harm the plates or parts containing the screw.  One of my colleagues used it recently to remove a stubborn and broken screw; the plate was brass and came out unharmed.

In general, from a chemistry perspective alum will only attack the interstices (structure) of ferrous metals. Brass, copper, silver,gold, aluminium etc would be completely unaffected. Stainless steel would be for all intents unaffected except if the surface is viewed at microscopic levels. Hope this helps?


Sent from my iPhone using Tapatalk

[Deggsie]

Alum is the last resort if all else fails. You don't have to submerge the whole plate.. just make a paste and apply on the screw head. If the opposite end has a 'well' fill that up. 
Alum usually works best with hot water but that just accelerates the process. Room temp water just takes longer.
Anilv
Ps.I've come across people recommending mixing alum with Vaseline to make a paste ..never tried it but makes sense.

Alum and Vaseline would not work. The alum crystals need to be dissolved to form an aqueous solution. An analogy is mixing plaster of Paris with Vaseline. It just would not start to react without the presence of water.

[vinn3]

remove dial screws without corrosion - penetrating oil.

[hofnerpres]

Just had the classic corroded in screw in a 1946 Bumper Omega - Very dried up but otherwise good.  Tried Lubeta since it’s basically thin solvent with a small amount of oil. The trick is patience. It takes a day or two for any liquid to get between the screw and the thead. Have a look on youtube for experiments using all the popular potions. Even overnight on large nuts the penetration is minimal. If you have room make a little moat with Rodico so the screw sits under your tiny paddling pool. Please get rid of the dial before you start. Practice servicing a couple of old indian hmt’s -the ones that say “fully serviced” they will get your skills well up to expert

[Jon]

I had some rusted and broken screws on a Rolex 2135 the other week. I couldn't remove them with a screw removal tool, so got some Bergeon Vissin heated up in a dish, which is Sulphuric acid. I guess about 20 to 30%. I didn't want to have to remove all the steel posts, such as the minute wheel post and yoke post which were pressed in steel posts, or the shockproof springs, so I suspended the part that had the offending broken screw in the Vissin and within 10 minutes it has completely dissolved. Here's a video I made for my Instagram account https://www.instagram.com/p/Crx14thLdsy/

 

[RichardHarris123]

Couldn't the parts not to be corroded be masked as in making printed circuit boards? 

Edited June 12, 2023 by RichardHarris123

[rossjackson01]

I had a stubborn screw on the back of a Fossil watch. One of four on the back, they were crosshead. It was solid and someone had tried before and almost made the cross head round. I tried with heavy pressure, but not heavy rotation, to move the screw. It was solid. I sort advice from the members. 

I placed WD40 on a cotton bud and placed it over the screw to soak. Did this a number of times. I used a flat edged screwdriver to allow purchase on the edges of the crosshead, then I applied rotational pressure. Only a few tries. It did not move. I did this system every day for nearly 1 month. WD40 followed by heavy pressure but not heavy rotation. Did not want to damage the crosshead anymore than it was. 

Nearly 1 moth later the screw moved! It was like it had never been tight. 10 minutes later I had changed the battery and the Fossil watch is like new. 

Good advice from the members. If you have to use heavy force, then you force a break. 

 

 

 

Edited June 12, 2023 by rossjackson01
Spelling, Grammar

[hofnerpres]

A month - Wow - That sort of patience is amazing. Those screw fixings on back casings seem to get welded in with heat and sweat from the wrist. I've had a few that needed lots of soaking but as you say - don't force them. The quartz cheapies often use lower quality screws.

[Galilea]

If none of the above works, try whispering to them sweetly, and promise the moon if they'll just come out and get it.

[rossjackson01]

1 hour ago, Galilea said:

If none of the above works, try whispering to them sweetly, and promise the moon if they'll just come out and get it.

I think you have let the secret out of the bag. You are probably correct in that all of us say something to our watches, even silently.