Pressure Test #4

This morning I completed the final pressure test and reached 8 meters down (11.76 psi).  Toward the end of this update I have outlined the reasons for stopping here.  The window gave no resistance to the pressure at that depth.  It was experiencing about 2,778 lbs/sq.in (1,263 kg/sq.in), even after hitting it all over with a rubber mallet, just to be sure.

Fig. #1.  5 meters down.

Fig. #1.
10/01/2017

Fig. #2.  6 meters down. 

Fig. #2.
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Fig. #3.  7 meters down. 

Fig. #3.
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Fig. #4.  8 meters down.

Fig. #4.
10/01/2017

Fig. #5.  Upon closer inspection I noticed that the ball valve had began to crack at 8 meters.  In case it suddenly failed whilst pulling a vacuum, and possibly damaging the pump if derbies went up the pipe, I decided to stop and replace it.

But after another look around the sub I saw that most of the plates making up the dome had began to go flat under the pressure.  These plates were actually made from a thinner steel than the rest of the hull.  I could go inside and weld more support for them but I'd have to stop at some point.

So I've decide that 8 meters is more than enough for a un-pressurized dive and will make it the maximum.  For safety I'll add a buffer below that of about 2 meters, so 6 meters un-pressurized.

I have also added these numbers to the Specifications page.

Fig. #5.
10/01/2017

Next will be Stage Two of testing.  As shown here.