Inspection Ports: How big and where?

Looking for advice on best practices. I have heard that on top of the deck forward of the front pylon is a good place, but have also heard that is a high stress area you don't want to weaken. Have also heard behind the front pylon, but that is potentially a foot traffic area. Also I hear you can't see or do much from there due to positive floatation foam filling most of the hull void between the pylons. The foam would also limit the port's value for storage bags, etc. In the rear pylon area, behind the pylon seems not to pose any great problems. I have seen 1 case where inspection ports were cut into the vertical inside surface of both hulls just forward of the front cross bar on a 21se for access to the wing pockets. That boat has been in service for years with no issues after the mods, but I would have a lot of difficulty getting comfortable with that. The boat in question now has no obvious damage but suffered a hard rollover on the beach in a storm with the sails up. Mast was destroyed but sails and everything else seems ok. May be a risk for pylon shoe failure.

So, the questions:
1. Best location for inspection/repair access near the front pylon?
2. Same for rear pylon area?
3. What is the most advisable size to have reasonable access without structural concerns?

Thanks for sharing opinions and experiences.

With regards to the rear access ports, I would recommend staying with the 4" port since the 5" port's hole thru the top of the hull will put you too close to the ~3/4" diameter bead of hard dried resin (that oozed out, on the inside, between the sides and top of the hull when it was manufactured). This bead will also get in the way of putting all the bolts thru for the 5" access hatch.

I have big hands, so I decided to cut the holes for the 4" ports, do all my work on thru bolting the gudgeons before I installed the 4" plastic ports. The hole that you will cut thru the top of the hull will be ~ 4½" in diameter vs ~ 3½" for the inside opening of the 4" port.

Bill Mattson wrote a good article in On The Wire entitled: Do-It-Yourself: Installing Deck Ports

http://www.thebeachcats.com/news/29/ins ... eck-ports/

_________________
Tim
84 H16
82 H16
87 H14T
Tortola Sails: 115222
Blue Prism Sails: 88863
Clearwater, FL