Build a Pressure Tester for 30 Dollars

[zsolie]

My nalgene leaks above 2,5 Atm, even with tighten cap. I have purchased one more, but is the same. Maybe here in Europe we have softer caps wich can deformate ? I wish one cap built from metal with silicone seals, that's it will be the right tool

 

[Wildcatfan]

I think this is an Improvement on the Nalgene bottle idea but to each to their own. Hopefully some will find this useful!


This is how you do a DIY post! Excellent work and completely thorough and understandable.

 

[VaderTime]

This is very interesting! I will soon build one using a larger and clear canister.

Wondering if someone else has came up with a better idea since 11 years ago lol

 

[Wildcatfan]

Got mine built and tested a few watches, Works great! Thanks for the parts list and info!

 

[drphillyfly]

Wish i read this post prior to pressure testing my watch! They charged me 40 bucks to do it :/

 

[dogwood]

So I built one of these to pressure test my 10 reps (I figured the economics were on my side given that it'd be $40 per watch to get someone else to test them). This was surprisingly easy. I think I spent around C$60 on the parts, but I already owned a 160 PSI 1/4" NPT pressure gauge from another project (but those are only around C$20)... so for the price of testing two watches you can probably build one of these yourself, assuming you have a few tools around and are reasonably handy.

I made a slight modification to the designs listed above. I used a dremel tool to bore holes into a structure of the lid so that I could take a piece of bent coat hanger and make a rung to hang my watches from with tape. Here are a few pics of my tester. Also, I only tested up to 6 bar (around 90 PSI) and I wore eye protection when I was using the device because I was kinda terrified I was making a bomb.

Also, it turns out none of my watches leak... or rather they're all water resistant up to a pressure of 6 bar (or roughly 60m or 200ft). It was kind of a good news / bad news situation. I really wanted to see bubbles because then I'd know my tester worked; but I also really didn't want to see bubbles because that would mean my watches were waterproof. In the end, no bubbles.

 

[davkra]

Really interesting concept and design. Will build myself something similar!

 

[anarchos]

Another good option is to get an inline water filter housing. Those are designed to take pressure and would eliminate having to re-tighten the lid of a Nalgene and there'd be no leakage around the drilled hole. I used one once to build a pressure vessel for a coolant system for a DIY CNC machine. The small filter housing usually have 1/4" NPT, so all you'd need is a 1/4" NPT bung to block off one side, and then a 1/4" NPT to Shrader valve adaptor. You could probably pick up everything on amazon (or local hardware store...maybe not the shrader adaptor?) for $20.

Edit: Apparently I can't read and there's a post above explaining exactly this. Sorry

 

[OddJob007]

I paid £165+ for mine off eBay.

I’ll be building one of these aswell over the weekend as a little project, I’ll update how I get along!

Amazing info, thanks for the time and effort put in!

 

[40mm]

I've always wondered what happens when a rep watch fails this pressure test. Is it not full of water, and ruined? You would have to quickly open it up and dry everything off before corrosion sets in. Would this not require a full disassembly?

I've always thought it was better to not try the test - but I may not be understanding something.

 

[dogwood]

I've always wondered what happens when a rep watch fails this pressure test. Is it not full of water, and ruined? You would have to quickly open it up and dry everything off before corrosion sets in. Would this not require a full disassembly?

I've always thought it was better to not try the test - but I may not be understanding something.

If the crystal pops off, you’re fucked. The watch is flooded and will require a full service — disassembly, cleaning, re-assembly, re-lubrication.

If the watch fails the test, the bubbles you see are high pressure air escaping into the water, but since most leaks are slow, the watch still has more high pressure air inside preventing the water ingress. Fluids flow along pressure gradients. When you release the pressure on the tester, if the watch leaks, it will still be full of high pressure air, while the surrounding water will be at low pressure. The air will flow from inside the watch case into the water to try to establish equilibrium. Obviously you can’t leave it this way for a long time. But it’s safe for 20 seconds or so for the test.

The safe way to test a case is to remove the movement from the case and test it empty. That way if the crystal pops off, there’s no damage.

 

[Fleischwolf]

Here I have a video tutorial on the concept shown earlier, it also has a parts list. He says you can pump it up to a maximum of 250 psi/17 bar!

 

[Eddio]

If the crystal pops off, you’re fucked. The watch is flooded and will require a full service — disassembly, cleaning, re-assembly, re-lubrication.

If the watch fails the test, the bubbles you see are high pressure air escaping into the water, but since most leaks are slow, the watch still has more high pressure air inside preventing the water ingress. Fluids flow along pressure gradients. When you release the pressure on the tester, if the watch leaks, it will still be full of high pressure air, while the surrounding water will be at low pressure. The air will flow from inside the watch case into the water to try to establish equilibrium. Obviously you can’t leave it this way for a long time. But it’s safe for 20 seconds or so for the test.

The safe way to test a case is to remove the movement from the case and test it empty. That way if the crystal pops off, there’s no damage.

Why not remove the movement, close the case, test it, and put the movement back in afterwards. Relately risk free and, guessing that most will not dive or go snorkling with it, knowing that the choice of seals vs case design gets it to 50 or 100m WR would be enough to know and reassure yourself it can handle rainy weather.

 

[dogwood]

Why not remove the movement, close the case, test it, and put the movement back in afterwards. Relately risk free and, guessing that most will not dive or go snorkling with it, knowing that the choice of seals vs case design gets it to 50 or 100m WR would be enough to know and reassure yourself it can handle rainy weather.

Yup that’s what I do now. It usually takes less than a minute or two to remove a movement from a case. The only risk is messing up the keyless works when you remove the stem. But knowing what position the stem should be in before releasing it minimizes this risk.