J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment J 30 bulkhead technical discussion

I have discovered after my recent purchase of Nice Pear that the bulkhead design has a flaw that WILL result in wood rot within the bulkhead. I have discovered that if I had sailed the boat once, the rig would have come down. Thank God I discovered this. Rod Johnstones' attempt to improve the bulkhead design from the J-24 is flawed because it traps the wood core between two fiberglass liners. If moisture gets into the wood, which is a matter of when, not if, rot will occur. I have hired a surveyor to have a look this Saturday to determine the proper method of repair. I STRONGLY suggest that a technical commitee should be formed to review this bulkhead problem, and determine a repair / retrofit that would be allowed under class rules, and that would possibly bypass the wooden bulkheads that we currently have. Frames have been used on racing boats that tie the shroud chainplates to the keel and hull without relying on a solid wooden bulkhead. I will be discussing these options on Saturday. Any strong structral solution that may or are may not be class legal, but provide safety to sail the boat safely again will be considered by us.

keep us posted on your findings. IMO this has become a largely non-issue when properly addressed annually during the entire life of each J/30 when we dig out last year's bedding compound and follow up with a fresh application of compound at the deck level turnbuckles. Each year @ launch time remove the deck plate, remove the old caulk, refill with new, rebed the cover plate.

I concur with Dell. The issue is from neglected maintenance, not a design problem. Digging out the caulk and rebedding around the chainplates should be normal annual maintenance on everyone's list.

I bought my J-30, a 1981 model, #363 in 1986. It had not been properly calked and I discovered an area of about six inches of delamination around each of my chainplates. I chose to repair the problem from inside the boat and keep the deck intact. I cut out the rotten balsa and sealed the area with epoxy. I filled the void with marine plywood sealed with epoxy and used west system to all the voids. I finished the head liner with kitchen counter type laminate to cover the area that I had cut out. I also injected epoxy into the bulkhead at the chainplate attachpoint area. It has held up great through the years. I too, recalk (if neccessary) each year.

Suggest at a minimum that the balsa core exposed around the chainplates should be covered with epoxy to prevent intrusion into the deck core.

Could someone explain specifically what the issue is here? When we bought #426, "J/24 bulkhead" issues were brought up as a concern but I was told that the plywood/bulkhead issues were solved getting rid of the plywood in the bulkhead on the J/30. But, this sounds like there's balsa core behind the chainplates.

Does this span the entire bulkhead? OR, is it just in the deck area around/above the bulkhead?

When I heard the plywood-J/24 issues had been fixed on the J/30 design, I sort of moved along. I have rebedded the deckplates/chainbplates at the deck with Sikaflex a couple times. But, any background and definitive details would be great here.

Thanks (and sorry if this has already been covered elsewhere in a post)!
- Jeff

Jeff - two issues. One is the balsa cored deck and the cutout area around the chain-plate. If not properly caulked, the core gets wet and rots. The fix is to dig out the area, recore and seal the edge with epoxy so water can't get in. Do NOT epoxy the deck to the chain plates because the deck needs to float relative to the rigging.

The second problem is if proper caulk is not done annually around the chain-plates, water can run down and wet the wood that the chain-plates are attached to on the bulkhead. This can result in a loss of structural integrity where the chain-plate attaches, and compromise the strength of the rigging.

The second is a maintenance issue, not a design issue. The first is a construction issue that is aggravated by neglected maintenance.

Oh Bill, I am afraid I must respectfully disagree. Anytime moisture can be introduced into wood that does not allow air to breathe, rot will occur. There are posts elsewhere in the forum that describe in detail the construction of the bulkhead. Unfortunately, the design of the J-30 bulkhead is counting on keeping the wood in the bulkhead dry. The chances of keeping water out of the wood in the bulkhead after 30 years, and multiple owners is very slim to none. Coming from the J-24 the problem is not unheard of, but it seems to be more prevelant in the 30. Moisture meter readings show moisture in the bulkhead from the chainplate all of the way down to the berth. Will be discussing with the surveyor on Saturday, but it appears that one of the fixes will be to cut away the fiberglass on the head side, remove all of the core and replace it with epoxy treated marine plywood, and NOT refiberglassing the head side. The port side is severly damaged, resulting in a crack in the fiberglass on the aft side. Inserting a knife in the crack shows mush. No damage yet on the starboard side, but still has very high moisture readings. Will probably be cutting away the core on both sides of the door, then replacing the core with marine ply. After the boat is sailing again, then I will be evaluating the hull to see if a "suicide bar" is required between the chainplates to stop the bulkhead from working. Don't know if this fix is class legal, but oh well.......

no need to reinvent the wheel here. your problem is the same as many others, the fix and the problem are well documented here on the forum.

1) remove all rotted core
2) isolate new core from water intrusion (epoxy + overbore & edgeseal methods)
3) rebed deck plates annually

congrats on the new boat. a survey would have been a good way to avoid the surprise. its not a huge problem but its a critical piece. where else do you have water? you might want to reschedule your survey a couple weeks, have your boat hauled, give it a chance to live in jackstands for a little while to give accurate meter readings, have the whole hull & deck moisture metered. talk it over w/ a few surveyors.

Thinking about the Cost to Repair vs the Market Value (CR/MV)-- most of us have a J30 because it is a great sailing boat irreplaceable at $20-$25K.

Last year I went to Waterline Systems to get an estimate on doing a non skid deck on Vee Jay 526... it was close to $7K!!!

the CR/MV "check" --which indicated 1/3 of the value of the boat to gain an aggressive non skid surface on the deck -- ruled it out. Instead I spent $300 for a kicked up Interdeck paint with additional silicon dioxide ... with enough left over to do the 505's deck.

My point is that the J30 is not a Ferrari ...if you are obsessed with keeping the boat as it was built ... you are going to spend a lot of money emotionally.

The easiest way to handle it may be to cut the problem area out from the forward side of the bulkhead, epoxy a piece of G10 to cabin side and firm up against the deck. and sail away. So OK you will have an extra 20 lbs of fiberglass around the chain plates.

If I remember right we've only had one case where the chain plate pulled straight out of the deck. But not the whole deck ripping apart.

So OK I'm a G10 addict.

Thanks for reminding me of the G10 core. I LIKE that idea!! I was looking at better core materials. Do you think that the difference in the "working" of the G10 vs. the wooden part will cause an issue in the future? Overall, the moisture in the boat is not bad. The boat was dry sailed while it was in Miami, and it is actually floating high on the marks. There are couple of spots on the deck that are moist, the area under the halyard stoppers, and under the port winch. The hull is pretty dry. I have seen far worse on other versions of J/Boats. I saw a 27 once that had a crack between the keel and sump that allowed water intrusion in the hull core all of the way from the keel to the deck. Nothing on the deck or hull is soft yet. Vic, guess we are located pretty close in the winter anyway! I can't really complain, I practically stole the boat.

While I'm a bit past the personal fiberglass-work-on-boat stage. Horatio, (my fiberglass guy and an ex Hinckley repair guy ... also at TP in the 80s when these boats were built) prefers to use G10 and Corecell as he did on this transom for 526. I think all that you are looking for is to spread the area for the attachment points with a solid base. for example the squares of G10 for the gudgeons. If there is a working between the elements ... I would vote that would not enter seriously enough to matter.

Vic, Where did you put your ID Plate?

He tacked it on and gelcoated around it.
this was before it was finished off even with the new gel coat.

Nice!

Laser Beam #192 had severe water penetration issues in the bulkheads near the chainplates when purchased in 2001. I drilled multiple holes, (drilling aft from the head and the hanging locker))at 1" intervals all around the chainplate attachments in the bulkhead, let the damaged wood dry out, and injected West system epoxy with high density filler into each hole. Also cleared out the rotted deck core in a six-inch circle around each chainplate cut-out, dried it out with my wife's hair dryer, and filled up the area with the West System epoxy mixture there as well, then redrilled the slot for the chainplates. That, and annual rebedding with silicone sealant of the chainplate hole in the deck, seems to be doing the trick so far.

OK we sat down with the surveyor, and the results are in. Not a big deal. Both chainplates are cracked, which was not really a big surprise. Everyone should have a close look at theirs. What he recommended is to extend the chainplates as long as possible. It looks like they can be extended another 18 inches, and replace the plastic backing plates with 1/8 inch aluminum. Do not reuse the existing holes. The surveyor thumped on the forward side of the bulkhead, and was happy with the soundness. Soooo, I will fill some holes with epoxy as LaserBeamer suggests, see if I can order custom chainplates from Rigrite and put the boat together again and gently go sailing. I only say gently, because the surveyor was VERY concerned about the original Navtec turnbuckles on the shrouds. We believe they are original equipment. Any thoughts?

Check out local welders ...re new sheets of SS. got to be some decent marine guys near Cape Canaveral. we did that with a local boat down here ... and while the welder was more into biminis and SS tops for fishing boats, he didn't blink when he saw the original chain plates .... [not from a j30 repair]...

Welders can use the originals for the top pattern. and wing it on the belowdeck. Suggest you go one thickness up. where were the cracks ... visible or betweendeck?

not impressed with the aluminium suggestion though. and don't remember seeing a plastic backing plate in use.

if the shrouds are original, you need to really check to see if there are any broken strands mostly at the swages ... generally we change shrouds every 20 years ... but with the cracked chainplate they may have gone though a "shock".
Hall used a beefier turnbuckle last time I had the shrouds done on 505.

This is the proverbial weak link in the chain. Something will give eventually. Do yourself a favor for the peace of mind, replace the 30 year old shrouds and turnbuckles. It won't make you go faster assuming you already tune for your sails, but it will sure make you sail more confidently knowing you don't have to worry about the rig coming down.

I agree with Vic and wouldn't use an aluminum backing plate. G10 is definitely the way to go.

I will be ordering new shrouds on Monday. As for the cracks in the chainplates, this is an issue that EVERYONE needs to have a look at. What happens is the holes create a weak spot. All of the cracks will eminate from the holes that bolt the chainplates to the bulkhead. I found cracked chainplates on my 82 J-24, a 79 J-24 in my fleet dismasted after his chainplates broke, and the same types of cracks are on my chainplates in my '30. Everyone should take a good look at theirs. I don't think that increasing thickness is necessary, heck they stood up for 30 years, new chainplates should last another 30. It would also be a good practice to remove the bolts, look for nicks on the surface, and replace if nicks are found. See the point about aluminum, could make a battery.

Thats happy news sailon! Replace the turnbuckles & studs for peace of mind. They have a defined service life that, if not already replaceded, they should be.

Absolutely. The whole enchelada. New rigging from the bottom chainplate bolt up to the top of the shrouds. I hope I get to finally go sailing on Sunday!!!
Sorry, I live in Florida. Cheer up folks up north, people are playing baseball now!!

If you order new chainplates, I found that our chainplates use grade 3006 stainless, which has a high carbon content. My new chainplates are using 3016 grade stainless which has a much higher chromium content.

Next question. After seeing what is happening to my bulkhead, is the base shroud REALLY 1800 lbs??? YIKES!!

It depends - on what tuning guide you use, based on the cut of the main. Tuning guides are available on the menu under "Info", "Articles of Interest", "J/30 Rig Tuning". 1800 pounds is not abnormal. The tighter the uppers are give more mast pre-bend due to the swept back spreaders.

Make sure you have the rig centered before starting any tuning. I use the bucket of water on the halyard trick. Just hang it over the port and stbd side at the same position fore and aft. Mark the halyard so it is even with a reference point like the top of the toe rail and adjust the rig so the halyard mark is at the same position on both sides

for those of you who don't remember what the plastic backing plate is ... I spotted it today ... but it never registered in my mind that there was a plastic backing plate there.

Stainless has arrived, hope to have it cut by the weekend. Will attach photos.

Chainplates out to measure for new ones. Oh boy, the cracking was worse than I thought at deck level. Readers digest version, is if you have a soft spot in your deck next to your chainplates, there is a REAL good chance that there is a cracked chainplate. Mine was 50% across the chainplate, all of the way thru the stainless. If I went sailing today, the mast would be toast. (20kts today) Going to let it dry out tonight, then play with epoxy and glass tomorrow. Will post photos later.

Wrap the chainplates with wax paper before you epoxy and glass just so you're sure you can pull them out after the epoxy cures.

Chainplates done. So now I have all of the parts. Unfortunately, the epoxy to strengthen the bulkhead takes a week to get to full strength. Lots of wood left, so mass quantities of Get Rot used to beef up the bulkhead. Drilled in a staircase fashion to fill all of the voids. Will have first look tomorrow. Core actually better than I feared. Strongly suggest that longer chainplates should be considered. 1800 lbs over 6 bolts just looks like trouble.

to all who were following this:

I was looking at the gear from Hull #420 yesterday. Ted has the Chainplates, the plastic/fiber backing plates with bolts. They appear to be in good condition. You can reach him at tkaper6862@aol.com or through his post on the for sale section of forum.

LUMPY

Nice pear finally went on her shakedown sail today. Boat is stiff and fast!!

Last year I noticed a crack in the bulkhead that extends out from the starboard chainplate approx 1-1/2 inches out. Fearing a saturated bulkhead and a major structural problem, I removed the chainplate this spring. There was certainly some major staining from water but I was surprised and releived to learn that the bulkhead was dry. With an awl, we probed each bolt hole and determined the bulkhead to be solid and dry.
Regardless, the crack is severe and goes completely thru the bulkhead. it propogates from the top inner bolt hole traversing slightly up and outward.
We will, of course grind out and fiberglass the crack on both sides. But further, we now have an oversized chainplate designed along with a matching backup plate. The oversized plate will carry additonal bolts and we hope, spread the load over a greater area of the bulkhead. Don't know what caused the crack other than sheer load on the shrouds so we're hoping the larger chainplate will add some strength and let us feel better in any severe weather situations

The oversized chainplate was drawn up in Solid Works and thus it is availabelin in a solid model and in 2D. If anyone is interested and wants a copy, let me know

Hi
On conundrum we are repairing the entire area of the port bulkhead from the deck to the bottom of the inside cabinet of the head. About 12 x30.
The plywood is all delaminated. We will replace with glass and retab it to the hull. The chainplates show no signs of fatigue. The main cabin side shows only a slight stain. The deck has been recored and there was a 3 in rradius of rot around the chainplate. The starboard side bulkhead is dry. The staining is greater indicating the water escaped the bulkhead and travelled the outdide of it. This will make 484 a new boat. Hope we can go sailing soon

Update on Nice Pear. No motion detected on the crack in my bulkhead. I purposely did NOT glass in the crack, but filled it with a mixture of epoxy mixed with hi density filler. This way I can monitor the stresses in the bulkhead. Nothing is moving so far, however, I am keeping track of the bolt tightness. I filled the bulkhead with Get Rot, and epoxy and so far nothing is moving. Some very strong suggestions. Anyone still sailing with the original shrouds should replace them. Suggest the Hall open body turnbuckles. Strongly suggest replacing the chainplates with larger chainplates using 316 grade stainless. Russ has the idea. Bad idea to reuse the stainless that came with the boat as it is 302 grade which has LOTS of ferrite in the alloy. They are also too small to take the loads. Finally, anyone who sails with 1800 lbs on the rig is crazy. My settings are currently 1300 lbs on the uppers and 1100 on the lowers. Been out in 20+ and NO slack observed in the leeward shrouds. When the rig is at the correct tension, the lowers should be just "kissing" slackness. I believe this is not helping the bulkhead situation in our boats. In 15 kts we were both higher and faster than the other '30 in our area. I suspect that the proper "base setting" is around 1100 on uppers and 900 on lowers, with 1500 uppers 1500 lowers the "storm setting" that should be reduced when the boat is put away. Overtensioning the rigs may be why the J-30s are getting a bad rap in light air. Tight rigs are certaintly not helping the bulkhead problems. The swept back spreader rigs that Rod made famous are great for getting rid of running backstays, however, a fractional sail plan still requires management of the mast shape for the conditions. Adjustment of the shrouds between races is the compromise.

The chainplates were removed on mine (USA 139) and the deck was redone on the topsides. All completely dry now, but I need to reinstall my chainplates. Any advice on this process?

I'm assuming you left about an 1/8" all the way around the plates when you redid the core area were the chain plates go thru the deck If so all you need to do is install te plates then pump the area full of silicone which will flex with the boat underload then put the caps on with a good bed of the silcone

You should be good to go with that for a couple of years