# Rudder freedom 40 **URL:** \ **Category:** General Discussion\ **Created:** [September 30, 2026, 5:46pm UTC](https://freedomyachts.org/t/rudder-freedom-40/12671 "2026-09-30T17:46:13Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![anna.please](https://freedomyachts.org/user_avatar/freedomyachts.org/anna.please/32/2914_2.png) [@anna.please](https://freedomyachts.org/u/anna.please)\ **Post date:** [September 30, 2026, 5:46pm UTC](https://freedomyachts.org/t/rudder-freedom-40/12671/1 "2026-09-30T17:46:13Z")
Hi everyone! I’d like to get your thoughts on our rudder. When we bought the boat, the rudder had quite a few blisters, just like the rest of the hull. We repaired everything below the waterline properly: opened every blister, repaired the deeper ones with fiberglass and epoxy filler, then applied epoxy, barrier coat, and antifouling. One of the deeper blisters allowed me to see a little of what’s inside the rudder. The core looked like some kind of foam, definitely not balsa. We’ve now been back in the water for over a year, and quite a few small blisters have appeared above the waterline as well. We pressed a few of them, and some rusty-looking liquid/staining came out, as you can see in the photos. After our last passage, we also noticed several small longitudinal cracks in the rudder. They don’t look severe, and the rudder has been working normally, but we’re wondering why the cracks have formed in this particular direction and what you think we should do about them at this stage. There’s also something else I’m curious about. As you can see in the photos, there is a ring attached near the top of the rudder, and while sailing a line runs from the wishbone boom to this ring. I assume this is a custom modification. Interestingly, it actually seems to help the rudder a little, almost like a very gentle wind-vane steering effect. We quite liked it. But I’m also thinking maybe water could be entering the rudder through this attachment point. What do you think about the condition of the rudder in general, the cracks and rusty-looking drainage, and this wishbone-to-rudder setup? Has anyone seen or used something similar on another Freedom? ![IMG_0987](https://freedomyachts.org/uploads/default/original/2X/5/5a4bdc8574512a5eedba65a3956e3ab2631d4f79.jpeg) ![IMG_1076](https://freedomyachts.org/uploads/default/original/2X/c/c63d3d2ad3e768347b047137a9221a62d2efe5ae.jpeg) ![IMG_1169](https://freedomyachts.org/uploads/default/original/2X/e/e4f365725d9380a607b5f47870c39d6652e2d0f2.jpeg) ![IMG_1170](https://freedomyachts.org/uploads/default/original/2X/7/768ecc5379d8f9f5c24e5ef43d854450a4eb3af1.jpeg) ![IMG_1171](https://freedomyachts.org/uploads/default/original/2X/3/3aa53aeab65d41a29a0b60fd73d8296a7340d165.jpeg) ![IMG_1697](https://freedomyachts.org/uploads/default/original/2X/b/b8db24db8f0eb40671cc81198b3fe3d61aeb1760.jpeg) ![IMG_1699](https://freedomyachts.org/uploads/default/original/2X/6/6068838f3e47b1ae3cb87ecee529bc801e7f558b.jpeg) ---
**Author:** ![RadioZephyr](https://freedomyachts.org/user_avatar/freedomyachts.org/radiozephyr/32/83_2.png) [@RadioZephyr](https://freedomyachts.org/u/RadioZephyr)\ **Post date:** [October 1, 2026, 7:02pm UTC](https://freedomyachts.org/t/rudder-freedom-40/12671/2 "2026-10-01T19:02:24Z")
My guess would be that pad eye on the top was added to make it easier to lift the rudder when removing it. Just a guess, though. I don’t know much about the F40, but the Mull boats were made with carbon composite rudder stocks, rather than the traditional stainless steel stock with steel flags welded to it. If yours is built this way, you don’t have to worry about water ingress, as there’s nothing inside the rudder to rust. Fiberglass and carbon fiber are perfectly happy being waterlogged. If your rudder has a regular stainless stock, you should think about maybe opening it up and inspecting it for corrosion. It would also explain the rusty spots on the outside. I’d figure out what’s inside your rudder first, ideally non-destructively—a magnet might work, or even a metal detector. If you don’t get a ping, you don’t have anything to worry about. ---
**Author:** ![ewsponberg](https://freedomyachts.org/letter_avatar_proxy/v4/letter/e/e47774/32.png) [@ewsponberg](https://freedomyachts.org/u/ewsponberg)\ **Post date:** [October 1, 2026, 10:19pm UTC](https://freedomyachts.org/t/rudder-freedom-40/12671/3 "2026-10-01T22:19:59Z")
Hi Anna, I was Chief Engineer at TPI when Freedom 40s were being built there, 1980-81. The foam in the rudder is polyurethane foam, 2.0 lb/cu.ft. density, fairly typical of the era. The rudder stock and armature inside the rudder are welded stainless steel, and if there is any corrosion inside, it is likely not too bad as oxygen, necessary for corrosion, has a hard time getting far into the rudder. Any water ingress is more likely to have come from the lower pintle/gudgeon than the top padeye. The cracks look to be mostly typical gelcoat cracks due to aging, but the cracking at the corners of the pitle/gudgeon recesses look more like stress cracks. It might be worthwhile to grand these back some until they disappear and then laminate more glass cloth or woven roving or biaxial braided fabrics over those ground out areas using WEST epoxy resin to seal them back up again. The rusty brown liquid coming out of the blisters above the WL is unused catalyst from the original construction. It is OK to open them all and patch them over with epoxy putty, e.g. using WEST epoxy materials. I hope that helps. If you have any other more detailed questions, you can email me at [eric@ericwsponberg.com](mailto:eric@ericwsponberg.com). Also, you can contact Paul Dennis at Warren River Boatworks in Warren, RI, for additional advice. paul used to be Productiion Manager at TPI for a lot longer than I was there, and he knows all there is to know about all Freedom Yachts. Link: [https://www.warrenriverboatworks.com/](https://www.warrenriverboatworks.com/). Good luck, Cheers, Eric Eric W. Sponberg Naval Architect (retired) ---
**Author:** ![hotstonp](https://freedomyachts.org/user_avatar/freedomyachts.org/hotstonp/32/76_2.png) [@hotstonp](https://freedomyachts.org/u/hotstonp)\ **Post date:** [October 2, 2026, 9:16am UTC](https://freedomyachts.org/t/rudder-freedom-40/12671/4 "2026-10-02T09:16:58Z")
I have a F33 sloop(uk) and whilst the rudder is different the problem was the same. I was told it was very common for rudders to be foam filled and then to fill with water. It was recommended to open it, remove the foam and then solid fill it. that was done, no more water filled rudder. ---
**Author:** ![anna.please](https://freedomyachts.org/user_avatar/freedomyachts.org/anna.please/32/2914_2.png) [@anna.please](https://freedomyachts.org/u/anna.please)\ **Post date:** [November 2, 2026, 10:13pm UTC](https://freedomyachts.org/t/rudder-freedom-40/12671/5 "2026-11-02T22:13:18Z")
Hello Eric! Wow, thank you so much for your reply! This is incredibly valuable information for me! I’ve already repaired all the blisters below the waterline, both on the hull and on the rudder, using fiberglass and WEST System. Just for fun, I’ll show you some photos. We certainly weren’t short on blisters… Haha! But we haven’t done anything above the waterline yet. We’re planning to tackle those when we haul the boat out. Thank you so much again! ![IMG_0147](https://freedomyachts.org/uploads/default/original/2X/9/950c4e25e096117bb0777a1c22df90aa3193e045.jpeg) ![IMG_0181](https://freedomyachts.org/uploads/default/original/2X/c/cbee700cb7c29809577b79123819498c69d10b13.jpeg) ![IMG_0262](https://freedomyachts.org/uploads/default/original/2X/8/830be8727bc1525508f420ab5aca6ad94a49bded.jpeg) ---
**Author:** ![anna.please](https://freedomyachts.org/user_avatar/freedomyachts.org/anna.please/32/2914_2.png) [@anna.please](https://freedomyachts.org/u/anna.please)\ **Post date:** [November 2, 2026, 10:14pm UTC](https://freedomyachts.org/t/rudder-freedom-40/12671/6 "2026-11-02T22:14:23Z")
Thanks! We will think about it when we haul out ---
**Author:** ![ewsponberg](https://freedomyachts.org/letter_avatar_proxy/v4/letter/e/e47774/32.png) [@ewsponberg](https://freedomyachts.org/u/ewsponberg)\ **Post date:** [November 3, 2026, 2:01pm UTC](https://freedomyachts.org/t/rudder-freedom-40/12671/7 "2026-11-03T14:01:08Z")
Anna, What year was your boat built? Presumably it is a TPI-built boat from Rhode Island, not a UK built boat? This blistering looks particularly bad across the whole bottom, but the blisters I am guessing are not very deep. When the boats were built, they sprayed the gelcoat into the mold first, and while that was still tacky, they shot in chopped fiberglass strand from a chopper gun, probably a light coating first, and again while still tacky, a heavier coat. Typically, the way the chopper gun works is it chops a string of glass fiber coming off a roll into 2"-3" or so pieces. As these pieces leave the gun they are sprayed with polyester resin and catalyst from two separate nozzles in the gun, and the spray is supposed to be fine enough that by the time the whole mess hits the mold, the resin and the catalyst are pretty well mixed. Final mixing occurs when the crew use ribbed rollers to roll the fiberglass down flatter in the mold. HA-HA–that’s the theory! Often, if the nozzles and/or the air pressure are not calibrated properly in the gun, the resin and catalyst are not mixed well. As a result, you get unmixed catalyst stuck within the laminate close to the outside surface of the hull. Polyester resin is notoriously porous because it is made up of two parts–polyester monomer and styrene. As the catalyst mixes with the monomer and starts to cure (harden) the styrene flashes off into to the air, and where it flashes off it leaves microscopic holes in the laminate. When the boat goes into the water at launch, the water migrates through these tiny holes (osmosis) and meets up with the unused catalyst, reacts with it, and turns it brown, swelling up in the process, leaving the surface blistered (the pox). When you smell fiberglass in a new boat, that is the styrene you are smelling, still flashing off. The same is true with the gelcoat which is also made of polyester resin and color filler, so you can get blisters just within the gelcoat. I’d say your boat had a particularly bad case of the “pox.” However, the repairs you made with epoxy resin (which is 100% solid on cure and has no microscopic holes) has fixed the problem forever. The whole problem of blistering began in the heyday of widespread fiberglass boat building in the 1970s to early 1980s. The US Coast Guard and responsible boat builders conducted a lot of research to define and cure this problem. So that is why I ask when your boat was built–I’d say late 70s to early 80s. Good luck on the rest of your repairs. Cheers, Eric ---
**Author:** ![anna.please](https://freedomyachts.org/user_avatar/freedomyachts.org/anna.please/32/2914_2.png) [@anna.please](https://freedomyachts.org/u/anna.please)\ **Post date:** [November 3, 2026, 6:08pm UTC](https://freedomyachts.org/t/rudder-freedom-40/12671/8 "2026-11-03T18:08:06Z")
Our hull identification number on the transom is TSPFF0181078, so I believe our boat was built in 1978. And as far as I know, she was indeed built in the US. Yes, there was only one deep blister that went all the way down to the balsa core, slightly exposing it. (I’ll attach a photo of it) The balsa looked great and was completely dry. I repaired that blister very carefully. All the others were much shallower, although I still repaired many of them with fiberglass rather than just epoxy and filler. I really wanted to do everything properly so I wouldn’t have to worry about it later. Thank you so much for the explanation! I’m genuinely incredibly happy to hear from you. It’s a little sad that we got so “lucky” with such a bad case of the pox, but oh well! Haha. While working on the boat, I also found voids in two different places that had nothing to do with osmosis. They seemed to be manufacturing defects. For example, near the bow, underneath several layers of fiberglass, there was a large air pocket, about 15 × 5 cm (6 × 2 inches). Definitely not osmosis. That was interesting to discover! By the way, perhaps you might know something about this, because we haven’t been able to find a definite answer. Does our centerboard contain lead, or is it supposed to be relatively lightweight? And what would be the proper way to inspect it? We’ve used the centerboard several times already, and it’s a wonderful feature! It seems to work perfectly well. But, you know, there’s always that little fear that it might fall off somewhere in the middle of the ocean, and we wouldn’t know what to do then. Haha ![IMG_0145](https://freedomyachts.org/uploads/default/original/2X/4/4a9b7108eedb9d11c1294894d7554804257596ea.jpeg) ---
**Author:** ![ewsponberg](https://freedomyachts.org/letter_avatar_proxy/v4/letter/e/e47774/32.png) [@ewsponberg](https://freedomyachts.org/u/ewsponberg)\ **Post date:** [November 3, 2026, 7:20pm UTC](https://freedomyachts.org/t/rudder-freedom-40/12671/9 "2026-11-03T19:20:48Z")
Hi Anna, For this vintage yacht, from the HIN: TSP = Tillotson-Pearson, FF = Freedom 40 (I believe), 018 = hull number 18, 1078 = October 1978. The big voids that you have found are sloppy workmanship. I wonder if this is a “Monday morning boat.” Not to worry too much, it has survived this long. Yes, the centerboard has some lead weight in it, but not very much. Some round holes were cut into the inner foam, I think to a specific pattern so that all the centerboards were the same (more or less), and then the holes were filled with lead shot mixed with catalyzed resin. The small amount of added weight makes the centerboard just less than neutrally buoyant so that they sink readily but then are not too heavy to pull up. If you lift the boat up in a Travelift high enough so that the centerboard can drop fully down, you could probably scan it with a metal detector to find out where the lead is located. A surveyor who is adept at using thermographic imaging would also be able to detect where the lead is. Ultrasonic testing might also work as the sound waves would readily bounce back wherever they hit the dense lead weight. Paul Dennis, who owns Warren River Boatworks in Warren, RI, and was the Freedom Yacht Production Manager at TPI for donky’s years when I was there, may also have more specific information as to where the lead weight is in the F-40 centerboard and how much. Link: [https://www.warrenriverboatworks.com/](https://www.warrenriverboatworks.com/). Paul has likely forgotten more than we others other employees ever knew. He specializes in the care and feeding of all Freedom Yachts. Hopefully, your centerboard will never fall off. The pivot pin would have to corrode through, plus the pennant would have to break (more likely than the pin). Of course, you could hit a reef badly and smash it all up, but then your navigation might be at fault, and that’s a whole different kettle of fish. Again, I hope that helps. Cheers, Eric