Horotec case opener: Size of bits?

[digginstony]

Bear in mind that if you ever want to modify the “bits” for most of these case openers, they should be glass hard. I shattered a Bergeon one recently, so I know! Anyway, if you want to modify the shape of one then you’ll need to be familiar with tempering. 

Re-shape mine with a diamond file. Brought to cherry red under a gas flame and doused in oil then cleaned off. Seem ok. I haven't come across a stiff Vostok back yet, they seem more awkward than tight.

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[Halvis]

I'm not very familiar with tempering, but it is one of those things I want to learn. It wasn't originally part of the plan to dive into this just yet, lots of other stuff going on at the moment.

May I ask why tempering is needed when modifying the bits? (I'm not questioning the fact that it must be done, just curious)

[rodabod]

23 hours ago, Halvis said:

I'm not very familiar with tempering, but it is one of those things I want to learn. It wasn't originally part of the plan to dive into this just yet, lots of other stuff going on at the moment.

May I ask why tempering is needed when modifying the bits? (I'm not questioning the fact that it must be done, just curious)

The bits will likely be extremely hard, by heat-treating high-carbon steel. This makes it so hard that you can scratch glass with it. It won’t bend either; it will simply shatter. 

So, it’s hard to re-shape when it’s like that! The easiest thing to do is to soften it by heating and allowing to cool slowly. This changes the crystalline structure of the iron/steel. You can now re-shape easily, and then harden again (to glass hard) by heating to cherry red for a minute or so, and then plunging in water, brine, or oil to chill immediately. The part can then be tested for hardness by scratching glass or seeing if a sharp file can bite into it at all (it won’t if it’s hardened correctly). 

[Halvis]

The bits will likely be extremely hard, by heat-treating high-carbon steel. This makes it so hard that you can scratch glass with it. It won’t bend either; it will simply shatter. 
So, it’s hard to re-shape when it’s like that! The easiest thing to do is to soften it by heating and allowing to cool slowly. This changes the crystalline structure of the iron/steel. You can now re-shape easily, and then harden again (to glass hard) by heating to cherry red for a minute or so, and then plunging in water, brine, or oil to chill immediately. The part can then be tested for hardness by scratching glass or seeing if a sharp file can bite into it at all (it won’t if it’s hardened correctly). 

Thanks for the explanation. Wasn't aware that you could soften it again. Then it makes a lot of sense. Is there a limit for how many times you can soften and harden the same piece before compromising the quality of the steel?

Is it sufficient to use a "cheap" gas torch for this purpose, or will I not reach a high enough temperature?

[jdm]

1 hour ago, Halvis said:

Wasn't aware that you could soften it again.

That's called annealing. If you search for this term here or on google / google books you will find many guides.

[rodabod]

4 hours ago, Halvis said:

Thanks for the explanation. Wasn't aware that you could soften it again. Then it makes a lot of sense. Is there a limit for how many times you can soften and harden the same piece before compromising the quality of the steel?

Is it sufficient to use a "cheap" gas torch for this purpose, or will I not reach a high enough temperature?

That’s a very good question. I’m honestly not sure how many times you can alter the temper without ill effect. 

A cheap blow torch is absolutely fine. 

[clockboy]

5 hours ago, Halvis said:

Thanks for the explanation. Wasn't aware that you could soften it again. Then it makes a lot of sense. Is there a limit for how many times you can soften and harden the same piece before compromising the quality of the steel?

Is it sufficient to use a "cheap" gas torch for this purpose, or will I not reach a high enough temperature?

This seems to be getting very complicated just to open a watch back. Have you considered a Jaxa tool . They work just fine and come with different size stumps

[Halvis]

This seems to be getting very complicated just to open a watch back. Have you considered a Jaxa tool . They work just fine and come with different size stumps

I'm not getting this machine to just open one watch back, but to open watches for the rest of my life. I have a cheap jaxa tool, and it is junk. You could argue that I can get a high quality jaxa tool, but I would like to have a bench opener. The bits of the jaxa would potentially need some modification as well to work perfectly with Vostoks.

[jdm]

18 minutes ago, Halvis said:

I'm not getting this machine to just open one watch back, but to open watches for the rest of my life. I have a cheap jaxa tool, and it is junk.

The problem is not the quality of the Jaxa tool, as it's easy to get a good one for little money. The problem is with  watches (mostly divers) which have been closed extremely tight. With these, any single handle tool will slip, due to the lack of vertical force. Unfortunately, it seems that two handles, four bits openers are not manufactured anymore. With these, one could can press down pretty good while turning.

[Halvis]

The problem is not the quality of the Jaxa tool, as it's easy to get a good one for little money. The problem is with  watches (mostly divers) which have been closed extremely tight. With these, any single handle tool will slip, due to the lack of vertical force. Unfortunately, it seems that two handles, four bits opener are not manufactured anymore. With these, one could can press down pretty good.

Exactly! That is one of the reasons why I want a bench opener.

[clockboy]

Ok the Horotec is a great tool very versatile and with a great solid build. However at the very begining of this post I was under the impression that it was not a Rolex or Diver that is why I suggested an alternative option. I have 3 different openers (excluding a case knife) I have a vintage Bergeron style opener which I normally use sometimes I use the Jaxa and always use the Horotech for Rolex or real tight ones etc. If non of these options fit then secure the watch in a vice  and tap it around with and old screwdriver. 

[Halvis]

Ok the Horotec is a great tool very versatile and with a great solid build. However at the very begining of this post I was under the impression that it was not a Rolex or Diver that is why I suggested an alternative option. I have 3 different openers (excluding a case knife) I have a vintage Bergeron style opener which I normally use sometimes I use the Jaxa and always use the Horotech for Rolex or real tight ones etc. If non of these options fit then secure the watch in a vice  and tap it around with and old screwdriver. 

I want to be able to use it on all kinds of watches, including my Speedmaster and a '70s Certina I have inherited that has a tight caseback. Certainly don't want to risk scratching those, or any other watches I might work on in the future. When I first get a high quality opener, I want to be able to use it on the watches I work on the most, which is Vostoks.

[clockboy]

What is the size of the slits/ holes on a Vostok cas backs. The Horotech has many pegs of different sizes including points which I presume are for the smallest of slits.They also supply many dies for specific Caliburs. 

[Halvis]

What is the size of the slits/ holes on a Vostok cas backs. The Horotech has many pegs of different sizes including points which I presume are for the smallest of slits.They also supply many dies for specific Caliburs. 

It was difficult to measure exactly, but they are just a tad smaller than the measurements you provided. So the Horotec bits would just require a small modification

[jdm]

It's not like you need the bit to fill the slot perfectly. The tool works applying torque in the exact direction, and even a small contact point will work fine.

[clockboy]

 

If you go to the Horotec web site you can access their  cataloge

 

 

 

 

[rodabod]

I guess the bit needs to be small anough to fit in the slot, if it is a slotted type. 

Cheap Jaxa copies are pretty crap as they have play which leads to more likelihood of slippage. The Swiss ones are good, and the two-handled version better still. 

I’ve been working on some extremely seized/fused case backs recently, and found that you can use 2-part epoxy to adhere a bar of some description (eg. thick brass strip) to provide a handle to remove screw backs. You can also superglue a large nut to a case back which works, but is not quite as effective. Acetone removes the adhesive in both cases and should be used to clean the surfaces prior to glueing too. 

[clockboy]

16 hours ago, Halvis said:

17 hours ago, clockboy said:

What is the size of the slits/ holes on a Vostok cas backs. The Horotech has many pegs of different sizes including points which I presume are for the smallest of slits.They also supply many dies for specific Caliburs. 

It was difficult to measure exactly, but they are just a tad smaller than the measurements you provided. So the Horotec bits would just require a small modification

If you can measure it you could contact Horotec and they will advise. 

[GuyMontag]

On 12/17/2017 at 10:59 AM, Halvis said:

I have considered the Chinese version, but I'm afraid it will have issues, and it is still a big investment.

 

I bought a Chinese clone of the 5700. The first watch I used it on I noticed that when one of the chucks was fully engaged in the slot on the caseback, the other chuck was about .75mm away from the slot. Looking closely at the head holding the chucks, the screw rod that the chucks are attached to was shifted to the left:

 

Luckily, it's an easy fix by breaking down the various pieces and just shifting the rod so it's centered. All in all I'm happy with the $75 ($150 w/shipping) purchase.

Edited January 17, 2022 by GuyMontag