TL;DR: You can have an idea of the internal pressure of the internal pressure of the bathmate by measuring how tall is the base. That’s especially simple in the 2-5 inHG range. Look at the attached table if you have a Hydromax 7.
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Hi guys,
I posted this on the Italian forum but got no response there.
I somewhat was able to measure pressure inside the Bathmate, so I want to share my experience with you.
FIrst off the Bathmate is not a pump: it works like a suction cup: when sealed over your pubes and the valve is closed, the base, which is deformable, tries to go back to its original shape, increasing its inside volume creating negative pressure. So, the negative pressure depends on the strength generated by the base in a particular moment, and the strength generated by the base depends on how compressed it is.
So I’m starting to think, “a certain amount of compression equals to a certain amount of pressure” and to confirm it I set up an experiment.
I built an “artificial pubis” with some rigid, smooth and flat material, I used the bottom of a plastic bucket, then I made a 1/2” hole at the center and fitted a vacuum gauge (0-30 inHG) I found on Amazon for 5 euros (the same used to sync carburetors) then I sealed the hole with hot glue so that no air or water would pass.
I filled my Hydromax 7 with water and applied it to the artificial pubis, got a nice seal, then checked the gauge and yes! It was measuring. Now, how do I know it is correct?
Bathmate declared somewhere a max internal negative pressure of 0.55 bar (~16inHG) for the Hydromax and the Hydroxtreme pumps, so I tried to go full pressure, but with my strength I could only reach 10-11 inHG, then I started sucking water from the valve with my mouth, in that way I could top 14,5inHG, but I’m pretty sure with a handball you could squeeze those 2 additional inHGs although the base was already VERY compressed, so I’m convinced the measurement was right.
So I’m starting to test various scenarios, air, water, water with some air, and by putting objects inside it. I measured vacuum and height of the base, with a rigid ruler, by keeping the bathmate as perpendicular as possible, and measuring only the rubber base, nothing else.
Air: the bathmate is not a good air pump, at all, since it works like a suction cup: air can expand and the base is too strong so even if you have a max compression the base is strong enough to return to the original shape (almost) releasing most of the internal pressure. An air pump needs to have a fully solid non-deformable cilinder.
Water+Air: Air inside the pump deteriorate performance, the good news is that an air bubble of up to 1inch doesn’t change internal pressure by much, so if you have such an air bubble during your pumping session, no need to worry about it.
Water: with water I had consistent measurements over various attempts, of which the results you can see in the attached table. You can see how the growth in pressure is pretty linear up to 5inHG then it grows exponentially, from 5 to 15 in just 0.8cm of compression. (Sorry, table headings are in Italian: Compressione=Compression, Altezza=Height, Vuoto=Vacuum, compression is 7.9 minus the height, since the base is 7.9cm uncompressed).
Rigid objects inside the bathmate doesn’t affect the measurements, regardless of size. Flexible object that become rigid after some expansion (like the penis) do the same once they became rigid. Very flexible and expandable objects instead will decrease the internal pressure, by compensating internal pump volume.
Another thing I was able to confirm is that when you have your bathmate under pressure and push it against your body, with the valve closed, you are counteracting the force genereted by the base: in that way you are reducing the pressure even to 0inHG with enough strength. This could be useful to do some kind of pulsing pressure routine.
What are your thoughts?
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At this point I’m curious if anyone with a disposable bathmate can try to make a hole somewhere in the cylinder and try to fit a vacuum gauge there and see if it gives a reliable measurement. That would be a nice mod. I tried by putting the entire gauge inside the bathmate but stayed to 0 (I suspect it works by measuring the difference with the ambient pressure).