Pumping, my version.

[bldoink]

I'm not the resident pumping expert.

Good luck!

[AnotherOldMan]

I haven't had a Radical Robotic Prostatectomy but it usually takes at least 3 "inflation/deflations" before I add the rings. Each time I pause about 1/2 the way and slowly count to 10 or 20 and then before deflating do the same. It's not an instantaneous reaction. It seems to take some time for the blood to flow into my dick to equalize the pressure. Going slower is just a part of avoiding injury.

A small amount of PDE5 does facilitate the process. I can eventually get to where I want to be without the drugs and have gotten to a point where I don't care for that "yucky" feeling I get with even with small doses. I suppose I could recruit my wife but while I'm pumping she is taking care of her own preparations and I don't want to disturb her without due cause!

[CanGetItUpButNoMore]

I've posted my experience in another thread but I'll also respond here. If I try to pump starting at a flaccid state, then my dick will not extend at all. It just engorges (and the head kind of gets sucked sideways into the cylinder wall, looking at me pathetically). Even if I start semi-erect, it will not lengthen, just engorge, more at the base and less at the head. If I start fully erect, the process is more effective; I'll get ½" more length and the engorgement is more even and "healthy".

The part where the head gets sucked sideways into the cylinder wall is disturbing. Anything less than a full erection has this result. I've tried lubing to see if the vacuum will pull the head up and straight but nothing seems to work.

[AnotherOldMan]

the head kind of gets sucked sideways into the cylinder wall,

Have had that happen usually with my water pump while taking a shower. I learned to soap up real good with warm water before starting and that seems to work for me. Water based lube is not real effective in a water pump.

The rest sounds odd especially considering you can get fully erect before pumping.
What kind/brand of pump are you using?

[CanGetItUpButNoMore]

What kind/brand of pump are you using?

Encore

[AnotherOldMan]

That's the brand I use with success. I did have trouble with the manual pump after dropping it. Could only get a "chubby" at best but switched to the electrical until replacement arrived.
You use the manual or both? Same result?
I would suggest trying a sex shop pump. Just to see if it is the pump. You can get them at a minimal investment on ebay. If you are able to expand and get rigid with a cheap sex toy pump then you have a defective pump.
Here is one I used for a few months until it broke!! https://www.ebay.com/p/21030649518?iid=382225773164
To use I had to trim the pubes and use water-based lube. Worked great for "exercises" until the hand pump broke.