Recessing SEL on Sub Rep

[SeikoFan]

Over in the Noob V9 thread Nikoel posted a great idea for recessing the SELs on a Sub Rep where the SEL sits more flush with the lugs than you might like (which seems to be most of them).

This is is what you do. Balls to the wall approach I was meaning to publish in the guide but never got around to it

you get 1.7/8[whatever#] spring bars

then you get Aroldite. Yeah you can see where it’s all going... this ain’t for the weak heartwd

so, next up you take the old spring bars out and put the new ones in. Play around the different sizes. Once you know which give you the best SEL, you keep those and discard the rest. Next you’ll notice that SEL wiggles. That’s to be expected since they are not 2mm springbars. What you want to do next is using a very thin tube of premixed A and B Aroldote and insert it into four of the SEL spring bar openings. Keep the SEL in perfect position manually whilst this is all happening. Don’t worry too much about the mess as Acetone will make quick work of the glue that got places you didn’t want it to. Do not underestimate how long that shit takes to harden. Take good amount of time to do this once. And do it right

repeart for the other end

I decided to take my own stab at a modification of his idea but didn't want to post more OT banter in the Noob V9 thread so I started this new thread.

As I understand Nikoel's idea you'd be epoxying smaller diameter spring bars into the SEL - biasing them toward the top of the circumference of the hole in the SEL so the SEL sits lower in the lugs.

Not wanting to commit to the permanence of epoxing the spring bars in (in case I wasn't happy with the result) I took another route.

First I experimented to see what size spring bar to use in place of the original 2.0 mm spring bar. A 1.78 mm didn't seem to give as much recess as I was looking for. A 1.5 mm spring bar gave a perfect recess (to my eye anyway).

Next what I did was take make a 5-layer thick stack of aluminum adhesive tape, and then cut a small strip about 2.0 mm wide. I then adhered the strip to the spring bar and cut it to length so the adhered aluminum didn't extend past the end of the spring bar body (so the spring loaded ends could move freely).

Here are a couple pictures in case that doesn't make sense.

Next I pressed the modified spring bar into the SEL with the aluminum spacer at the top of the opening. It was a tight fit which is good because the spring bar must be unable to rotate in order to preserve the relationship of everything and maintain the recess.

Next I installed the SEL and spring bar back into the watch. The result was a perfectly recessed SEL - to my eye anyway.

Of course on the bottom side of the watch the result is that the SEL is no longer flush with the lugs and sits "high" by the same amount that the SEL sits low on the top side. This isn't really a problem since nobody will see the bottom of the watch - so who cares?

Sadly I did not take a picture of the result - sorry about that. Though I think the cosmetic outcome was fantastic I decided not to stick with the arrangement.

Why?

The flaw in the implementation is the 1.5 mm spring bar. Perhaps it is that the particular 1.5 mm spring bars I had on hand are just cheaply made and have crummy tolerances, or perhaps it is inherent in 1.5 mm spring bars, but the ends (the spring loaded parts that move) don't fit super tight in the sleeve and they can wiggle more than the ends in the original 2.0 mm spring bars. The result is that even though the spring bar body is very tight in the SEL (it doesn't wiggle at all), the ends can wiggle and this translates into the SELs being able to move around more than I'd like.

Perhaps a higher quality 1.5 mm spring bar can be had, or perhaps there is a way to crimp the ends of the tube a little so the spring loaded ends don't wiggle so much.

I think the right answer is just for Noob/ARF et al to get their act together and fix the SELs. I would imagine that they have them drawn up in SolidWorks or AutoCAD or some other CAD software and taking 0.5 mm off the top side would be a trivial matter. If they ever do that it would be nice if they would let us buy the updated bracelet separately so we can "fix" their prior less-than-stellar work.

Thanks to Nikoel for his great idea. I'd be interested to hear if he has the same problem with wiggly ends on his 1.5 mm spring bars or not. Like I said, maybe I just need a better quality 1.5 mm spring bar and this would work perfectly. It would still bug me a little that the bottom side of the watch looks odd with the SELs sitting high, but I'd rather have that than have the top side of the watch (that everyone sees) looking "wrong" with nearly flush SELs.

Anybody else try this approach or any other approach that worked well?

Honestly I like the way the nearly-flush SELs look, but it's not "right" compared to gen, so it bugs me.

Should I quit being so damn picky and just live with it?

 

[capice]

sounds good, any pics of the finished product?

 

[SeikoFan]

OK, I decided to take another stab at it using a 1.78 mm diameter spring bar and my adhesive aluminum strips. Honestly I think it came out perfect. I think the 1.5 mm spring bar would have been too deep of a recess.

What do you all think of this?

This is what it looked like before:

 

[capice]

:drinks_cheers: looks great

 

[nikoel]

Over in the Noob V9 thread Nikoel posted a great idea for recessing the SELs on a Sub Rep where the SEL sits more flush with the lugs than you might like (which seems to be most of them).



I decided to take my own stab at a modification of his idea but didn't want to post more OT banter in the Noob V9 thread so I started this new thread.

As I understand Nikoel's idea you'd be epoxying smaller diameter spring bars into the SEL - biasing them toward the top of the circumference of the hole in the SEL so the SEL sits lower in the lugs.

Not wanting to commit to the permanence of epoxing the spring bars in (in case I wasn't happy with the result) I took another route.

First I experimented to see what size spring bar to use in place of the original 2.0 mm spring bar. A 1.78 mm didn't seem to give as much recess as I was looking for. A 1.5 mm spring bar gave a perfect recess (to my eye anyway).

Next what I did was take make a 5-layer thick stack of aluminum adhesive tape, and then cut a small strip about 2.0 mm wide. I then adhered the strip to the spring bar and cut it to length so the adhered aluminum didn't extend past the end of the spring bar body (so the spring loaded ends could move freely).

Here are a couple pictures in case that doesn't make sense.

Next I pressed the modified spring bar into the SEL with the aluminum spacer at the top of the opening. It was a tight fit which is good because the spring bar must be unable to rotate in order to preserve the relationship of everything and maintain the recess.

Next I installed the SEL and spring bar back into the watch. The result was a perfectly recessed SEL - to my eye anyway.

Of course on the bottom side of the watch the result is that the SEL is no longer flush with the lugs and sits "high" by the same amount that the SEL sits low on the top side. This isn't really a problem since nobody will see the bottom of the watch - so who cares?

Sadly I did not take a picture of the result - sorry about that. Though I think the cosmetic outcome was fantastic I decided not to stick with the arrangement.

Why?

The flaw in the implementation is the 1.5 mm spring bar. Perhaps it is that the particular 1.5 mm spring bars I had on hand are just cheaply made and have crummy tolerances, or perhaps it is inherent in 1.5 mm spring bars, but the ends (the spring loaded parts that move) don't fit super tight in the sleeve and they can wiggle more than the ends in the original 2.0 mm spring bars. The result is that even though the spring bar body is very tight in the SEL (it doesn't wiggle at all), the ends can wiggle and this translates into the SELs being able to move around more than I'd like.

Perhaps a higher quality 1.5 mm spring bar can be had, or perhaps there is a way to crimp the ends of the tube a little so the spring loaded ends don't wiggle so much.

I think the right answer is just for Noob/ARF et al to get their act together and fix the SELs. I would imagine that they have them drawn up in SolidWorks or AutoCAD or some other CAD software and taking 0.5 mm off the top side would be a trivial matter. If they ever do that it would be nice if they would let us buy the updated bracelet separately so we can "fix" their prior less-than-stellar work.

Thanks to Nikoel for his great idea. I'd be interested to hear if he has the same problem with wiggly ends on his 1.5 mm spring bars or not. Like I said, maybe I just need a better quality 1.5 mm spring bar and this would work perfectly. It would still bug me a little that the bottom side of the watch looks odd with the SELs sitting high, but I'd rather have that than have the top side of the watch (that everyone sees) looking "wrong" with nearly flush SELs.

Anybody else try this approach or any other approach that worked well?

Honestly I like the way the nearly-flush SELs look, but it's not "right" compared to gen, so it bugs me.

Should I quit being so damn picky and just live with it?

Good job! Dedication and cohoness to build on top of the idea. Your way is better. If you don’t mind I’ll put it in the guide [sometime in 2030]

 

[SeikoFan]

Good job! Dedication and cohoness to build on top of the idea. Your way is better. If you don’t mind I’ll put it in the guide [sometime in 2030]

I would have never thought of the approach if you hadn't posted it, so all credit goes to you. My modification (using the aluminum foil tape instead of epoxy) was just because I'm too chicken to commit to a permanent modification. This way if I decide I want to go back it's easy.

 

[SeikoFan]

I've been playing around in SolidWorks (CAD program) a bit and think I've designed something that would be relatively simple to make and would be a little more elegant than aluminum tape strips.

I've ordered some stainless capillary tubing that should be here by the end of the week. When the stuff comes in I'll go spend a little time in the machine shop and see how it goes.

 

[SeikoFan]

The 2mm (OD) capillary tube showed up today. These are the same as the OD of the original spring bars and will become part of the new eccentric spring bars. Hope it turns out like I planned it in CAD. I'll try to get over to the machine shop tomorrow to mill the capillary tube and then mate with a 1.78 mm spring bar.

Fingers crossed.

 

[Rush]

You had these capillary tubes specially made for you?

 

[machim]

The 2mm (OD) capillary tube showed up today. These are the same as the OD of the original spring bars and will become part of the new eccentric spring bars. Hope it turns out like I planned it in CAD. I'll try to get over to the machine shop tomorrow to mill the capillary tube and then mate with a 1.78 mm spring bar.

Fingers crossed.

Can I order some from you? And I think a lot of people here would love to buy it, if you can make it <3. If you do, please let me the first in line. Thanks

 

[capice]

looking forward to your finished tubes,...if they turn out ok, I would love to order some...I think you can expect a lot of orders from the forums.

 

[SeikoFan]

You had these capillary tubes specially made for you?

No. I built the eccentric spring bar assembly in CAD so I could figure out what the wall thickness of the tubes would have to be so that a 1.78 mm spring bar would nest down into a half-tube (half circumference) exactly the right distance so the overall diameter of the eccentric would be in the neighborhood of 2.12 mm. The way I've designed it if I put RTV or some other cushiony adhesive in the half-tube to glue the 1.78 mm spring bar into it, it should compress slightly and act like an interior spring forcing the 1.78 mm spring bar away from the 1/2 shell - which will create friction in the inner surface of the hole in the SEL and provide a snug fit so the assembly doesn't rotate out of position. Wow, that was a long sentence - sorry.

Anyway, once I figured out what the tube thickness needed to be I went and found stainless capillary tubing with an OD of 2.0 mm and an ID of the dimension from the CAD model.

When the tubing arrived today I initially thought the ID was under size but that's just because there is an ever so slight curl to the "mouth" of the tube where they cut the segments. After chamfering the mouth of the tube they are indeed exactly the right ID, so I have high hopes that the assembly is going to work very well.

Machining these tiny tubes is going to be a little tricky. I ordered a 2 mm ball mill so that I can machine a fixturing block to hold the tube for machining. The machining isn't extensive - I just need to remove half of the diameter - but in order for everything to come out the right dimension it needs to be exactly half of the diameter (1 mm), and it needs to be consistent along the length of the tube.

Eh, it may all be for nothing if it doesn't work the way I hope. If it works out that way I can always just repeat my narrow strips of aluminum-tape stacked on a 1.78 spring bar (like in the OP). Not as sexy but it works fine - it's just a real pain to make and not super DIY friendly.

 

[dom1986]

SeikoFan i tried the same with the ali tape. Man you got to have hands like an action man to get it in. I failed miserably.

Keep us updated on your progress. If you get any to market ill take a few and put on mine.
Good luck

 

[Rush]

@SeikoFan Excited about your findings. This is truly what the hobby is about. I think we're all perfectionists at heart here, and are just trying to make what is imperfect > perfect.

I take it that you are a mechanical engineer by trade?

 

[freediver]

my only concern is whether there will be some play
how is the fitment ? do they move up and down when pressed?

 

[SeikoFan]

my only concern is whether there will be some play
how is the fitment ? do they move up and down when pressed?

The spring bars I made out of 1.78 mm bars with aluminum tape are rock solid, no play. The pictures of fitment are toward the top of this thread. The watch looks great and everything is tight. Honestly if I was just concerned about my watch I'd be done because I'm completely happy with my solution. In fact I really don't want to take my spring bars out to play with the ones I'm trying to make because it was like micro surgery making the little strips of aluminum tape and positioning them just so. But I'm always striving for something better so I'll take one for the team so to speak.

I went to the machine shop this morning and machined the capillary tube to make the 2 mm diameter half shell that will get glued to the bottom of the 1.78 mm spring bar to make the eccentric.

As is usually the case machining the fixture to hold the work took longer than machining the piece did. It turned out exactly as I wanted and measured out perfect. What you see below is an over-length piece. Two 16.5 mm long half-shells will get cut from this piece to make the bottom part of the eccentric.

See the shell on the bottom in the CAD image below:

I have some other stuff I need to do during daylight hours today so I'll mess with cutting and gluing sometime later tonight.

 

[capice]

micro surgery indeed....:thumbup:

 

[SeikoFan]

Well, I have one spring bar glued into the 2 mm half shell and drying. I have to say that was A LOT more tedious than I expected it to be. Cutting the 2 mm half shell to be the exact same length as the main tube of the 1.78 mm spring bar is precise work, but is easy compared to gluing the spring bar to the half shell while trying to ensure the whole thing is the right height from end to end, etc.

Right now I'm actually using my digital caliper as a jig to hold everything straight and at the correct height while it dries. Definitely not an ideal situation. The adhesive is Permatex Black Silicone Adhesive Sealant, so the excess will clean up easily. I chose this as the adhesive because it should be a little compressable even when fully cured, so the two pieces should be able to crush toward each other somewhat when pressed into the hole, resulting in a firm fit that holds the spring bar in a fixed position so it doesn't rotate.

I guess we'll find out after the glue dries.

 

[SeikoFan]

OK, good news and bad news. The good news is the new eccentric spring bar worked AMAZINGLY. Not only was it an absolute breeze to install, the fit was VERY firm and snug (no way it's going to rotate). I just oriented the shimmed side to the bottom of the SEL, pressed it in using the tip of a precision flat blade screwdriver, made sure it was centered on the SEL. Done! Install SEL into watch case like normal, PERFECT.

You might remember from the OP that my first stab at this was stacking layers of very narrow strips of aluminum tape (about 1 mm wide) onto a 1.78 mm spring bar and pressing that in. That approach came out excellent for the bottom SEL, but the top SEL wasn't quite as awesome - failing to achieve a satisfactory level of recess at one of the lugs.

But with the new spring bar I built today, both ends of the SEL appear to be equally recessed and I am VERY happy with the amount of recess compared to before. The top SEL still isn't recessed quite as much as the bottom SEL, but there's nothing that can be done about that other than going down to a 1.5 mm spring bar and I'm not doing that because I find the 1.5 mm spring bars to be too flimsy. The SEL recess at both top lugs is even and deep enough to create enough contrast to make me very happy.

So that's the good news. Now the bad news.

The bad news is this spring bar was a son-of-a-B to make. The time spent to make the jig to machine the capillary tube is a one-time thing so I don't count that. I have the jig now. I can machine as much capillary tube as I need easily.

But cutting off a precise length of the machined capillary tubing (which must be done very carefully as it is SUPER thin and deforms easily) is a tedious process. Then there is the RTV silicone adhesive used to glue the 1.78 mm spring bar into the shell. First, you have to apply it under magnification, using a toothpick, and it still gets EVERYWHERE because you have to hold on to the part you're applying it to somehow. But then you have to somehow hold the two pieces in precise alignment for 5 hours to let the adhesive cure sufficiently for assembly. I chose to use my digital caliper to do that, and it worked very well for the task, but I don't have a dozen digital calipers lying around and making one spring bar every 5 hours seems like a terrible plan.

So...

I need to come up with a way to make these things a little easier to make. They work AWESOME, but they take too damn long to build. I say "they" even though I only made one so far and used it to replace the aluminum-tape-stacked spring bar in the top SEL from the first attempt. The bottom SEL still has the spring bar from the first attempt in it.

One option for making this easier to make would be if I could fashion up some sort of gluing jig that I could just set the 1.78 mm spring bar in, then fill a shell with RTV, and lay it in on top of the spring bar, and then have some sort of top half that holds everything in proper alignment. I think making such a jig might be a royal pain in the butt - and I'm not even that sure how well it would work. If the two halves aren't glued together and held in precise alignment I don't think the finished product would produce a satisfactory result.

That said, I have another idea that would still use the machined capillary tubing along with a 1.78 mm spring bar, but would be A LOT easier to assemble. I'm going to try that first and see how it goes.

OK, bad news aside, pics of the outcome with this design of the spring bar are needed, so here goes.

Here is what my top SEL fitment looked like before:

And here is what it looks like now:

That's all for now. More when I have something else to report.

P.S. No, I did not take a picture of the new eccentric spring bar. It was basically impossible to photograph and be able to see any detail. The CAD drawing earlier in this topic gives the best idea of how it is constructed. The only difference between the CAD drawing and how it's really done is the void between the shell and the 1.78 mm spring bar is empty in the CAD drawing whereas in the actual assembled article that void is filled with black silicone RTV adhesive.

 

[capice]

:thanks::applause: