Hydro Oil conversion - Help me prepare

[sappyg]

I think it is exactly what they used for hydraulic fluids.

Till

should this be the case the question now is whether to use light weight or heavey weight yes?....

most equipment operators go light in the winter and heavier in the summer. but in this application i'm guessing light weight would be more desirable.... no moving parts to worry about plus you would need the fluid to move quickly and fill all voids.

[onrypt]

Please don't take this question as smart-alecky, but why would you want to do this conversion on a relatively inexpensive watch? It's my understanding that the oil filling is performed for instruments that are under immense pressure, ie: deep water. Since you can't compress a liquid those instruments are kept safe. Usually they come from the factory that way and I've had instruments (boost gauges for my car) that were oil filled for accuracy reasons.....
Is there another reason to perform this on a G-Shock, or any watch for that matter?
Cheers,
Chris

[sappyg]

possible bennifits are increased legibility and temp stability..., plus it sounds kinda cool

[tfar]

Additionally you get better shock proof and water proof ratings. But essentially it's just for bragging rights and the modding adventure, as I said in the first post.

You basically get one of the toughest watches on the planet for less than $200. Believe me, I wouldn't open up a Rolex for a hydro conversion though I'm sure it has been done.

Till

[freeman]

So did you arrive to any conclusion regarding the bubble ? does the silicon really expand at high temperatures ? is the bubble really needed ?
Because the mod seems easier to perform by plunging the case inside the silicon, without creating any bubble.

[sl8763]

Personally, I would go for no bubbles (although I suppose with a small one you could "show off" the mod a bit more). Since the watch will probably never see a fraction of its new WR, the functionality of having a bubble for expansion is not necessary.

[tfar]

So did you arrive to any conclusion regarding the bubble ? does the silicon really expand at high temperatures ? is the bubble really needed ?
Because the mod seems easier to perform by plunging the case inside the silicon, without creating any bubble.

Personally, I would go for no bubbles (although I suppose with a small one you could "show off" the mod a bit more). Since the watch will probably never see a fraction of its new WR, the functionality of having a bubble for expansion is not necessary.

I think I will try the plunging method. If there is a bubble it will be minimal. If I want to make it bigger it should be easier to open the case just a tiny bit and squeeze some oil out than to try and fill it and then quickly close it to only leave a tiny bubble. The other thing is that you might not even see the bubble of it's "captured" behind the module. I don't know if there are any separate nooks and crannies in the case.

Expansion should be due to temperature not due to pressure.

If you look at the Clearco products specs the thermal charts tell you that higher density (higher viscosity) oil has less expansion but they are all fairly close. So I don't think there is much to fear by not having a bubble if the highest temperature the watch will ever be at is around 60C. The flash point is around 350C.

Water has a viscosity of 1cSt. I read ketchup, surely there are different types, has a viscosity of 50000cSt. SAE40 motor oil is between 650-900.
http://www.vp-scientific.com/Viscosity_Tables.htm

If you put oil in a watch with moving parts, I think a low viscosity would be better. But in a watch with no moving parts (is the A.EL. sensor exposed to the oil?) a thick oil would give better water resistance and shock proofing.

In the posts I've seen people have used oils between 350 and 1000 cSt. I think I'd try the 1000 unless someone explains to me why that's too thick or I can't source it.

http://en.wikipedia.org/wiki/Polydimethylsiloxane

Interestingly, silicone oil is what is used in silicone breast implants. I'd be interested to know in what viscosity grade. Gives a whole new meaning to G-Shock hydro conversions. ;)


Till

[freeman]

So according to you the denser oil expands less at high temperature. And doesn't interfere either with electronic components. So it seems to be better for that. Are there any downsides ? just assuming, maybe the weight (even though it shouldn't be felt), and maybe the visibility (I suppose less dense oil would give better visibility?...)
Now with the breast implant issue : I guess they started to use a less dense silicone just lately, because the older implants are often hard and so not appropriate IMO !

[Sjors]

Personally, I would go for no bubbles (although I suppose with a small one you could "show off" the mod a bit more). Since the watch will probably never see a fraction of its new WR, the functionality of having a bubble for expansion is not necessary.

I have no experience with Hydro mods, but I know the bubble is indeed needed to compensate for expansion of the oil. I remember there was a test with a Mudman without a bubble that "exploded" after getting warm.

For more information you might contact ADAN of Commando-G. Unfortunately he doesn't speak English well, but he might help you further.

http://www.risingsunwatches.com/foru...splay.php?f=42

Cheers,

Sjors

[tfar]

So according to you the denser oil expands less at high temperature. And doesn't interfere either with electronic components. So it seems to be better for that. Are there any downsides ? just assuming, maybe the weight (even though it shouldn't be felt), and maybe the visibility (I suppose less dense oil would give better visibility?...)
Now with the breast implant issue : I guess they started to use a less dense silicone just lately, because the older implants are often hard and so not appropriate IMO !

Well, let's say according to how I understand what i read and not according to me. :) Both are equally di-electric. Visibility? Good point. I bet nobody has ever wondered about the refraction index of a damping fluid. :) Something with a density close to water would probably have the better optical qualities under water. Actually the denser stuff is closer to water in density but still not quite as dense. The lighter oil flows like water (viscosity) but is much lighter in specific weight (density). Chalk one more down for the higher range.

Regarding implants, they actually used different methods, from a bag filled with oil in the very beginning to harder gel substances. It's an interesting topic and the gel bleed is actually directly related to the oil formulation. Very technical stuff. But, hey, I'm a bloody art historian, so what do I know?

Weight difference is likely less than a gram I suspect. Quantities are minimal.

The only thing that may make a difference is the auto light sensor.

Till