Replace the crown and tube on 1665?

[devilseam]

Hi Guys,

 

New to this game so please be patient!

 

I have a trusty time 1665 that I what to mod, firstly I would like to change the crown. I have read the tutorials re shaving the crown guards which im going to do. However I cant find tips on removing the tube and replacing it.

 

Im thinking about getting a gen tube so firstly will it fit the case? Do I need to modify it in anyway?

 

Also whats the best way to remove the old tube?

 

Thanks!

[cib0rgman]

The tube usually is locked by glue, you need to remove all the rubber seals and heat the case with a blow dryer, to soft the glue, then use a filer or something similar to turn it, I am not sure if the Gen tube is a straight fit I have a MBW watch and those need to retap.

[Ephry73]

For the gen tube you will need to retap the case for the correct thread/pitch. If you're not reusing the old tube in the case you don't need to worry about destroying it.

[devilseam]

For the gen tube you will need to retap the case for the correct thread/pitch. If you're not reusing the old tube in the case you don't need to worry about destroying it.

 

Is there any information on retapping?

 

If I leave the tube in place will the gen crown fit on the old tube?

[freddy333]

Due to the variability & lack of manufacturing QC on rep watches/cases, it is impossible to predict what you will need to do to fit a gen crown or tube to a given rep case. However, with a bit of work, they can usually be made to fit. Similarly, it is impossible to predict whether a gen crown will fit your aftermarket tube. It is always best to replace with gen parts whenever possible. To be safe, get a tap. To remove the old tube, insert a small, 3-sided hobby file (most hardware & hobby stores sell them) into the tube & wedge it inside so you can unscrew the tube by turning the file. Once the tube is removed, apply a bit of oil into the existing hole & slowly screw the tap in. Go in a bit, then unscrew the tap a bit to allow the bits of metal to be expelled. Repeat until the tap is all the way through. You now have a fresh set of threads the correct size to fit a genuine tube. There are tutorials in the Watchmaking forum, but, basically, you can either use the same file again to install the tube or use the proper Rolex tool (the inside of the new tube will have splines that interlock with the Rolex tool, which makes installation very easy).

(click pic for link)

 

 

Whichever way you go, apply a bit of semi-permanent Loctite to the threads of the tube & then screw it in gently. It is difficult to explain how tight to make the tube (this is 1 of those things that require some experience), but screw the tube in until it seats. Then just snug it up using finger pressure. You are not torquing the thing down! Just snug. Then you can insert the stem into the movement & screw the (gen) crown onto the tube (again, just snug, not tight).

[Ephry73]

What Freddy said

[Nanuq]

Nicely said, Freddy.

 

Now how does he go about switching his stem from the old crown to the new crown, and getting its length right?

 

This is a good tutorial! 

 

Noobs?  Pay attention.

[dieselpower]

Nook, you have highlighted something that I have always been wondering about. I understand new tubes and threads etc and also new crowns onto those tubes, all fairly straightforward but I never understood how the new (gen) crown fits onto the rep (presumably eta) stem of the movement. Come on experts - explain please and put us out of our misery.

[Ephry73]

The stem should have the right size thread an pitch to fit the gen crown. This far I have not had a problem. The gen crown tends to be longer in reach than the Asian one. If the gen tube is used then you should be ok. It is always good to compare the length of old and new tube and old and new crown to see if the length needs to be altered in any way.

Incidentally, I have used stems for both the Asian eta clones and the Miyota /DG based clones with no issues.

[freddy333]

The threading (on most modern stems) is somewhat standardized, so crowns are interchangeable. The business end of stems - the part that fits into the movement - varies, which is why you need to match the stem to the movement, not the crown. You can use a pin vice (available from all watch parts houses) to hold the stem when changing crowns. With the stem held in the pin vice, simply unscrew the crown with your fingers & screw the new crown on (do not use tools to tighten the crown or you will strip the threads). You need to tighten just enough to keep the crown from unscrewing during use, but not so tight that you strip the threads. This is 1 of those things that takes experience & practice.

I am pretty sure these things have been covered in 1 or more pinned articles in the Watchmaking forum. But, if not, this info has been posted a number of times over the years to a number of threads that you should be able to find via the search.

[devilseam]

Due to the variability & lack of manufacturing QC on rep watches/cases, it is impossible to predict what you will need to do to fit a gen crown or tube to a given rep case. However, with a bit of work, they can usually be made to fit. Similarly, it is impossible to predict whether a gen crown will fit your aftermarket tube. It is always best to replace with gen parts whenever possible. To be safe, get a tap. To remove the old tube, insert a small, 3-sided hobby file (most hardware & hobby stores sell them) into the tube & wedge it inside so you can unscrew the tube by turning the file. Once the tube is removed, apply a bit of oil into the existing hole & slowly screw the tap in. Go in a bit, then unscrew the tap a bit to allow the bits of metal to be expelled. Repeat until the tap is all the way through. You now have a fresh set of threads the correct size to fit a genuine tube. There are tutorials in the Watchmaking forum, but, basically, you can either use the same file again to install the tube or use the proper Rolex tool (the inside of the new tube will have splines that interlock with the Rolex tool, which makes installation very easy).

(click pic for link)

 

 

Whichever way you go, apply a bit of semi-permanent Loctite to the threads of the tube & then screw it in gently. It is difficult to explain how tight to make the tube (this is 1 of those things that require some experience), but screw the tube in until it seats. Then just snug it up using finger pressure. You are not torquing the thing down! Just snug. Then you can insert the stem into the movement & screw the (gen) crown onto the tube (again, just snug, not tight).

Wow, thanks so much. Its a lot clearer now.

[Nanuq]

Another simple trick: if you have new gaskets in your crown, you can use it to screw the tube into the case.  Screw it down until it won't screw in any further.  That seats the crown against the case, and should have the tube all the way in.

 

Then when you use the watch, tighten the crown slightly less than that, and your gaskets will remain expanded to fill the gaps inside the crown.  As the gaskets compress over time, you'll find you're screwing the crown down all the way to the case every time.

[lionsandtigers]

Not sure about whatever case you have but with the original mbw case you also had to drill some metal out between the lugs in order for the tube to seat properly. The gen tube has a diagonal edge where it sits in the case and most cases are flat. So drilling that part, as well as the retap, is necessary in order for the tube to screw in all the way and the crown to sit flush with the case.

[panerai153]

lots of cases have been boogered up by the modder who gets a little too vigerous while trying to countersink the case to allow the tube to sit flush with the case. before you start drilling tapping, etc, i would find a couple of old throwaway cases to practice on.

Another thing, when you retap the threads, you need to be very careful that you are tapping straight into the case, as you can retap it to where the new tube screws in at a slight angle, and it may look OK, but it will bind the stem when you put the movement in and attach the stem. One of the keys to all types of  precision work, is the need to secure your work (Case) in some sort of vise or holder so that it does not move. If it's loose, and you can't line everything up correctly, you are going to have a mess on your hands.

[automatico]

"Not sure about whatever case you have but with the original mbw case you also had to drill some metal out between the lugs in order for the tube to seat properly. The gen tube has a diagonal edge where it sits in the case and most cases are flat. So drilling that part, as well as the retap, is necessary in order for the tube to screw in all the way and the crown to sit flush with the case."

 

I have one of the later MBK L342301 '1680' cases and it is bored to accept a genuine or genuine spec case tube and gasket (the gasket between the case tube and case). The case threads were A-Ok and I cleaned the glue residue out with a pipe cleaner dipped in acetone...taps are too risky when the threads are Ok.  

I was really surprised because this is the first replica case I have owned that would accept a genspec case tube and gasket. I had a Yuki 1680 case a couple years ago but I got it from a member and it already had the case tube in it so I do not know how it was machined.

 

I have a couple DW cases and they will not accept a genspec ct/gskt combo because the relief for the ct O ring is a bit small but you can use a smaller rubber O ring between a 'TC' type case tube and case for a fair seal. Be sure to lube the O ring with silicone grease so it will slip into the recess in the case and watch closely when turning the case tube into the case to make sure the O ring does not get cut. You can poke it with a toothpick to keep it 'in the groove'.

'TC' type case tube = case tube with flat surface where it goes up against the case, no shoulder or tapered area on the case tube.

I bought a miniature carbide cutter to make the relief for a genspec gasket in this type of case but have not tried it yet. The catch to this is mounting the case solidly and lined up precisely with the cutter bit.

 

The genuine spec case tubes I use are 'Tech Swiss' brand and are exactly the same as oem. I got them from J. Borel a few years back and they have a full set of threads where they screw into the case same as oem where some other brands may fewer threads. I noticed some of the short thread case tubes did not have exact oem spec threads and they would bind and break off in the case.

Otoh they seemed to work Ok on cases with sloppy threads. 

 

old info:

Submariner type 7.0mm case threads are the same as regular DJ etc 6.0mm case threads...3.0mm x .35mm and the installation tool is the same.

[devilseam]

"Not sure about whatever case you have but with the original mbw case you also had to drill some metal out between the lugs in order for the tube to seat properly. The gen tube has a diagonal edge where it sits in the case and most cases are flat. So drilling that part, as well as the retap, is necessary in order for the tube to screw in all the way and the crown to sit flush with the case."

 

I have one of the later MBK L342301 '1680' cases and it is bored to accept a genuine or genuine spec case tube and gasket (the gasket between the case tube and case). The case threads were A-Ok and I cleaned the glue residue out with a pipe cleaner dipped in acetone...taps are too risky when the threads are Ok.  

I was really surprised because this is the first replica case I have owned that would accept a genspec case tube and gasket. I had a Yuki 1680 case a couple years ago but I got it from a member and it already had the case tube in it so I do not know how it was machined.

 

I have a couple DW cases and they will not accept a genspec ct/gskt combo because the relief for the ct O ring is a bit small but you can use a smaller rubber O ring between a 'TC' type case tube and case for a fair seal. Be sure to lube the O ring with silicone grease so it will slip into the recess in the case and watch closely when turning the case tube into the case to make sure the O ring does not get cut. You can poke it with a toothpick to keep it 'in the groove'.

'TC' type case tube = case tube with flat surface where it goes up against the case, no shoulder or tapered area on the case tube.

I bought a miniature carbide cutter to make the relief for a genspec gasket in this type of case but have not tried it yet. The catch to this is mounting the case solidly and lined up precisely with the cutter bit.

 

The genuine spec case tubes I use are 'Tech Swiss' brand and are exactly the same as oem. I got them from J. Borel a few years back and they have a full set of threads where they screw into the case same as oem where some other brands may fewer threads. I noticed some of the short thread case tubes did not have exact oem spec threads and they would bind and break off in the case.

Otoh they seemed to work Ok on cases with sloppy threads. 

 

old info:

Submariner type 7.0mm case threads are the same as regular DJ etc 6.0mm case threads...3.0mm x .35mm and the installation tool is the same.

Thanks for this info.