Inspection Port Locations for Super Porpoise

Thread starter #1
I have two 6" ports and two 3.5" ports that I would like to install on my SP. Yes, yes, I know it's a bit overkill, but I'm looking to make use of a lot of storage and also to do some extreme drying out of this old boat.

I've been debating about locations to put them, since I haven't been able to find any diagrams showing where Super Porpoises have extra deck supports/flotation blocks.

I'm considering putting two 6" in front of the splashguard, and to each side. I'd like to put the 3.5"s behind the cockpit to each side, or perhaps, one in the cockpit facing forward or reverse.

I've heard that putting the port directly in the center of the stern isn't a good idea on a SP, as there is a large amount of support about 6" wide that is best left alone.

Any advice?

Once I get these ports done, a little bit of deck paint and a lot of drying out, and my refurbishment should be done!
"...I've heard that putting the port directly in the center of the stern isn't a good idea on a SP, as there is a large amount of support about 6" wide that is best left alone..."
That was likely my earlier advice from my Porpoise II experience. (If there's a difference in the SP and PII hulls). In retrospect, I wouldn't put more than a 5" port in the rear "corners". If you save the cutout deck pieces from the 6" ports, you could make a "backup ring" for the underside of the smaller ports to add support to the deck around those ports.

I should have added earlier that there are several large foam blocks centered inside the hull—forward of the cockpit: How consistent the manufacturer's "build" during its production run(s) is unknown.

From my experience, I'd locate the forward ports as far from the centerline as possible, but keep in mind that even a 6" port doesn't allow much "wiggle room" for repairs. For example, my composite halyard cleat is worn out: but to repair it, I've put my one 6" port on the wrong side of the flotation blocks! :eek:
Thread starter #3
Well, the cutting has begun! Hopefully these efforts will be useful to other SP owners, so I'll try to document as best as I can. I'll post pics later.

The first port I cut was a 3.5" on the port side, directly behind and to the left of the cockpit. There are massive foam blocks in the stern, and I came up right to the side of one. Interestingly, at one part there seemed to be a cone shaped hole chiseled out of the foam, but I can find no evidence of there ever having been another hole cut in the hull. I was greeted with about a centimeter of water all along the insides of the boat.

There may also be a horizontal block of foam running directly behind the cockpit (although it doesn't extend to the sides of the boats.

There is no foam running on either side of the cockpit.

The second port I cut was on the starboard side, a few inches above the splashguard. I managed to get half of the foam block in my port for this cut, and I made the decision to cut that area of foam down substantially, so I could see inside the hull. (I'm going to strengthen that area of the hull in the future.)

The foam was quite moist in this area, but still looked to be dryable. However, when I cut the foam, I found that some of the interior of the foam had turned green, and was rotting away. There is also a substantial amount of brown "dirt" like substance on the bottom of the sides. (perhaps rotted away foam??) Doing any significant replacing of this foam is really beyond the scope of this project, but ideas for how to deal with this are more than welcome. At the moment, I'm going to just try and dry it out as best as I can.

I have a 3.5" and 6" port yet to cut, and am debating on locations for them. I had been planning on putting both parallel to the current ports, but may opt for different locations to get a better view inside.