Pump vaccum expressed as weight

I’m not an engineer either, so if one comes along he can tell me I’m full of it too. :)

Assuming the pressure is the same inside the penis and tube, isn’t all the “stretch” exerted entirely over the opening of the tube? So at 5” Hg (multiply by .4912 to convert to psi) a 2” inside diameter tube would be pulling with 7.7 lbs. independent of penis diameter or shape.

Actually, if the tube is packed the friction along the sides would reduce the tug at the base.

Both proposals sound viable to me since I don’t know enough about this area to know better. But in trying to weigh it up I just had one of those lateral leaps in equating this with condom pumping, the Bib and manual stretching:

I think the Bib is mostly credited with the best capacity to add weight, and it does it by excluding blood. The pump is the most accommodating but suffers from a poor internal grip (i.e. edema before you can even blink).

What if we had something like the catheter that had a nipple to attach to a vacuum pump to really compress it onto the penis? It would mold exactly to whatever shape your penis was and pull as hard as you care, knowing that every part of the structure was taking part of the load! That would be cool for hangers, stretchers, ADS as well as other variants.

Just a thought…

Yes, though you could reduce that a lot with lubrication.

Several devices like this have been tried. I don’t recall the name of the commercial stretcher using catheters. A search on catheter here will probably turn it up. There is a vacuum attached hanger, and again I don’t know its name. We’ve heard mostly bad things about it.

Either way the same problem remains. Attaching to skin, whether with suction or friction (such as swim cap) isn’t an ideal way to hang much weight. Getting a good grip on the internal structures is the way to go.

Hobby,

The basic theory I used here was that vacuum pulls the same amount at every surface of the penis, regardless of orientation. A larger diameter cylinder will not subject the penis to any greater vacuum or any greater pulling force than a smaller diameter cylinder that still fits the penis. All the larger cylinder will do is suck more pubic mound and scrotum into the cylinder.

The question is how hard are you pulling lengthwise on the penis. To really get technical, you would want to take the integral of the lengthwise component of force over the entire surface of the penis. Any area that is not parallel to the stretching force contributes to the total. The shorthand way of saying this is that pulling force equals pressure times the cross-sectional area of the penis.

Now that I think about it, my earlier comment regarding curved penises getting greater pull was probably bogus. It’s wrong because the curve will not only add to the pulling force (by pulling out on the outwardly sloped surfaces) but will also tend to equally and oppositely compress the penis (by pulling back on the surfaces facing backwards). I should have stuck with my first answer. Force equals pressure times penile cross-sectional area.

>The basic theory I used here was that vacuum pulls the same amount at every surface of the penis, regardless of orientation.<

Right. But the pressure within the penis rises to some degree also. If the internal shaft pressure rises to near equilbirium with the vacuum drawn in the tube, a good portion of the penis isn’t being “pulled on” very much. The primary pull is at the base, and increases with the cross-sectional area.

> A larger diameter cylinder will not subject the penis to any greater vacuum or any greater pulling force than a smaller diameter cylinder that still fits the penis. All the larger cylinder will do is suck more pubic mound and scrotum into the cylinder.<

A larger tube won’t cause any more vacuum because vacuum is determined by the user.

A larger tube at a given vacuum will provide more total pulling force than a smaller one, no? But I understand what you’re saying: the extra area isn’t useful because it’s not affecting the shaft, only sucking in more scrotum skin. So, you’re right, shaft base area is probably a more accurate figure than tube cross-section.

An oversized tube shouldn’t diminish the pull. Won’t help, but won’t hurt either. A tightly-fitting (packed) tube may reduce it to some extent because of the skin friction, though as Shiver pointed out, lube may make it negligible.

I’ve just checked my gauge and 1 Bar shows a little under 30Hg, so does that mean I should multiply by 25.4?

Hobby,

From the penis’ point of view, there is no difference between a fat cylinder and a thin cylinder. The pressure on the penis is the same. Therefore, a fat cylinder can’t stretch the penis any more than a thin one.

You are correct that the wider shaft will exert more force against the body in total; however, only a portion of that force is actually exerted against the penis. The rest of it acts upon the surrounding pubic tissues, which I think offers no benefit for PE.

Shiver,
Here’s a link to a page that shows conversions between different units of pressure: Transtronics electronics

You’ll see that 1 Bar = 29.54 in Hg. Therefore, it appears that the reading of 30 Hg on your gauge refers to inches Hg, not millimeters. No need for any additional multiplication. Just use the formula above for inches Hg.

This should be an easy calculation because, with your girth, 5 inches Hg corresponds to 5.88 lbs of length stretching force. This should scale proportionally. So, for example, 10 Hg on your gauge will give 11.76 lbs of stretch.

ModestoMan, Chay (from the Hawaii 5-0 crime lab) aint got nothing on you! I think you also have Bill Nye the Science Guy a little bit nervous also. :)

Careful, Sixerman. The only heads that should be swelling on this site should be on our peckers!

Blood flow anywhere is a good thing :)

Ah, okay. I got a little confused with the jumping between the metric and imperial measurements. I think I now have a good rule of thumb to work with.

Thanks again Modesto.

It’s called a vacuhanger and it’s great. I hang 8 lbs for two hours twice a day and i’ve gained in length and girth. A little fluid build up on the glans but it goes away in ten minutes and is not uncomfortable. Best money i’ve ever spent on PE.

Wow. That’s rather involved. I’m getting ready to buy a pump. I’ve been doing PE for a bit, mostly hanging with a vacuhanger lately, but this is going to be new to me. Is there an easier way to translate the weight I’m hanging into pressure? I just don’t want to blow out the ol willie :)