Moved to Watchmaking.

 

I didn't see a repair forum so I figured I would ask this question here.

There's the watchmaking forum here!

Is there some trick to doing this or are some watches just a pain?

Yes, and yes. Some difficult to close snap backs can be put on with a press intended for closing the snap backs. If you don't care too much about the watch, you might have luck with some sort of clamping device (vise, pliers, etc.) as long as you use something rigid on the back and front of the watch so you don't bend the case back or break the crystal. Ideally, the dies that fit the caseback press have a cutout so they only press on the front of the watch on the bezel rather than on the crystal.

You can even get a cheap one at Harbor Freight.

-s-

 

Also, many watchmakers quickly develop strong thumbs. Perhaps a word of caution is in order about what Skootchy appears to be showing in the photo above. Apologies in advance if I am wrong, but that appears to be a potence for inserting tension ring crystals, not a case closing potence. These are equipped with nylon blocks that are shaped somewhat similar to the aluminum blocks used in a tension ring inserting machine, but unlike the aluminum block of a tension ring inserting potence, they won't scratch the case.

They call this levered tool a "potence" in French, by the way, but I am tres desolee because I have no idea if there is even an English word for it other than "case closing tool".

 

I believe the English word is "press" but could be mistaken (it wouldn't be my first time either).

 

You're correct, that tool is a multiple use tool when equipped with the proper dies. I use it with nylon dies for closing casebacks.

-s-

 

That would be a BB Crystal press. It does work nicely for closing case backs giving a lot of control for those hard to close cases. I usually use the nylon dies also.

 

Would this one be good?

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=91621

 

Would this one be good?

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=91621

Not good, but if you're just closing up some Fossils it should be OK. However the lever may be too short to get good leverage on backs that are really tight, so you may need to bolt it to a workbench or use a pipe or something to extend the lever.

-s-

 

get a tower and put the watch against the door frame with crystal on the door frame side with tower between it and put all your body and weight behind and push with your thumb.

hope it will snap into the grove.

 

As a caseback closer that one is good enough.

As a crystal inserter, sometimes the two dies don't stay parallel, and you have to rotate the work 180 degrees and press again.

 

but the OP was about casebacks, correct? if so then the link to the tool from harbor freight is just fine.

 

Perhaps the point Lysander was making is that these are dual purpose tools. I might add that they are used for pressing down bezels also. What Lysander mentions about uneven pressure gets very meaningful indeed. If you've ever pressed a bezel on crooked, you know that it is no fun at all getting it off again, and then trying to get it back on properly with a tool that isn't square.

For years I used a screw press by MKS, a Japanese company. I wondered why I was always having problems with it, and one day did some simple measurements. It turned out the tool was manufactured out of square, as many inexpensive crystal presses are. I spent some real money on a potence made by A & F in Switzerland. It has a lot of problems as a crystal press, the main one being that it can not open wide enough to accept a thick watch, and the method of attaching the nylon case blocks in not good.

On the other hand, it is utterly precise , totally square, heavily built and allows me to exert force evenly across the whole case back or bezel to seat it evenly.End of problem.

I'm generally a friend of Indian made watch tools. Some of them offer good quality for the money. The inexpensive watch cases closers sold by Harbor are Indian. But I will not have them in my shop, along with Indian made tweezers and files. They are OK for some work, but are not, in my personal opinion, professional quality.

Another important use for an accurate potence is to flatten various bezels, dials and other case parts, particularly in chronographs that have been bent out of flat. On older watches this is a frequent problem .There a precise potence or press is essential.

 

Yeah, for now i just need it to put the caseback on, not for the bezels. I now have four watches total that I will need this tool for plus there are still a few more watches that I haven't opened up yet so in the end it will be worth the small investment.

Here in NYC average price to change a watch battery is $10. So I bought a watch repair kit on Amazon when I ordered my Seiko. I figured these tools will pay for themselves in the long run.

 

$10?? that's awesome. it's $15-20 here depending on where you go. that's hot springs, arkansas. kinda pricey huh? when i do batt changes for people i only ask 10.

 

So far I paid like $13 for the basic watch repair kit from Amazon and it was $21 shipped for the case press from Harbor Freight and I spent about $35 on batteries for all the watches. I changed the batteries in 7 watches, so everything already paid for itself. Plus I had fun doing it so that was a bonus.

 

dude. get your batteries from jules borel. they start at $.35-.50 cents a piece.

 

I had one of those blue presses like Watch Art shows above and the handle snapped the second time I used. All I did was press as hard as I could using both hands and it snapped giving me a bad pinch that hurt like heck and turned the pinched area quite black and blue! I had to use a 1 foot long by 3/4" piece of hardwood to get the Citizen watch back back on. I simple put all my weight on it and rocked a bit and it snapped on.

 

Well I received the press today and closed the three watches I needed it for. I actually had to put all of my weight on it to get the back on one of the Fossil's. I really didn't think it would be that hard. The other two just snapped on with ease.

Now I just have to place an order for some spare batteries to have on hand for future needs.

Thanks for all the advice guys.

 

It has been a few years since the last entry but I thought would add something anyway. To put the back on a Fossil I use automotive tools. A 1-1/4" socket and a large "C" clamp. The socket surrounds the crystal so the pressure is applied to he case. The "C" clamp is placed over the watch and socket and centered on the case back. Tightening the "C" clamp pops the back on nicely.

 

As an update for folks struggling with this issue, Bigtools was spot on! I used a medium sized C-clamp and a table saw blade wrench flattened against the watch back. (Citizen)
The wrench is flat (1/8") and gradually widens to approximately 2". This allowed it to cover the entire back-- very important. You want the entire back of the cover to be impacted by the clamping. Also, a 1"x4" piece of wood served as the base. The crystal was resting on a thin piece of rubber matting.

it took several attempts and finally, after tightening to near-crushing status, the back worked it's way in. There was no "snap" or cracking sound. I had to let this setup "set" for a minute to ensure that it would finally re-attach. I tried softer materials to surround the back cover, such as nylon, wood, etc. LOL, the wood cracked in half but the crystal was intact! Go figure.

Note: A Citizen time/date watch. Stupid watch, actually. it's the first date watch i've owned that will not allow the user to set the date back. It only advances the date forward. Like I said: Stupid. I'll never buy Citizen again.

 

It has been quite a while since the last entry (6 years). There are some decent crystal/case presses that are available cheap which would be a better option than a C-clamp and automotive sockets. Pressure is easier to control and less likelihood of damage to the case. I have found that it is much better to use tools that are designed for the task at hand.
Samantha

 

As Samantha says, the correct tools work correctly.

If you were applying enough pressure to crush wood with the G clamp then it wasn't pressing straight because no way should it take that much pressure.

Especially on a Citizen - in over 25 years of doing this professionally (that's a lot of watches btw) I've NEVER seen one of their snap backs that wouldn't go on with simple thumb pressure applied properly.

As for the date change, if you pull the crown out a single click you can wind the date on quickly without having to turn the hands through 24 hours each time. That's completely normal for almost every watch made by anyone over the past couple of decades, almost all of which will only turn the date forwards.

So not such a "stupid watch"!

 

In my limited experience all Seiko, similar brands and fancier watches required manual, no tool, hand force to snap a cover back on. Removal was straight forward with a case knife.

Then there's the no brand, disposable, watch that proved I really needed to change my technique as well as adding another tool to the arsenal. Mounted watch into large all metal case holder and further secured watch with packing tape. Used case knife with mallet/hammer along with a good deal of force. Reinstallation of the cover was equally difficult, required both hands squeezing the hand held press. It made a very positive snap sound of confirmation.