Hull Flexing?

[ted_reshetiloff]

I have noticed on my 89' E-38 -200 that the cabinet which the galley sink and icebox sit in seems to have lifted away from the cabin sole along teh section that runs lengthwise and connects to the dinette seat. I will take a picture tomorrow and post but I am wondering if I have somehow flexed the hull. It is very strange as all the doors seem to close fine and the rig tension is not screaming tight. I dont know if it was like this and I am just now noticing it or if it has come from sailing the boat hard upwind. There doesnt seem to be any paly that I can detect when sailing, nor can I move the cabinet by pushing on it but it looks like it has been lifted up 1/2 t0 3/4 of an inch. I know pictures pictures pictures. The door to the v berth is hard to close but has been that way even when the boat was on the hard with rig down. Nothing else seems to have shifted or moved and teh aft cabin and head doors close fine, but this has me a little concerned... More to come once I take the pictures.

 

[Mikebat]

I have the same sort of thing going on with my galley sink cabinet in my E32-200, also 1989. The post that is bolted to the side has also lifted up from the sole. Like you, I don't see any movement under sail, and I can't find anything that moves. Nothing else in the boat seems off-kilter.

I wonder if you have a low-profile traveller like I do, screwed into the top of your companionway hatch sea hood. Look at this thread I started a few days ago: http://www.ericsonyachts.org/infoexchange/showthread.php?t=2115

Is this happening to you? Maybe the traveller is pulling up the cabin top, and with it, the post and the cabinet.

 

[ted_reshetiloff]

I dont have the traveler mounted like you do. It is secured to the cabin top at the ends. I also do not have a post from the cabin top down. I saw your post earlier with your issue. It is very puzzling what is going on on my boat. There is nothing connected to the cabinet that could be PULLING it up. Its almost like the keel or hull or floor is somehow flexing and pushing it up. But it does not appear to be happening anywhere else as the aft cabin doors shut smoothly.

 

[u079721]

Had the same with my 38

Ted we had the exact same experience with my 38. I was concerned enough about it that I called PS and spoke with an engineer there. It seems that this is common to at least the 38s, and they called it settling. Something about the older hull design not begin adequately supported on the larger hulls like the 38.

I think mine was worse than what you describe on yours. In my case, when the boat was on the hard each winter there was no gap, and the trim on the inboard edge of the cabinet by the aisle was level with the cabin sole. But after launch I would see about a ¾” gap under the cabinet – and worse – would see that the cabin sole had seemed to drop that same ¾” away from the trim edge in the aisle. Which made it noticeable in the cabin if you knew what to look for.

The story I got was that this was not a critical concern. It could be reinforced so as not to settle, and that had been retrofitted to a couple of boats, but it was a lot of work. I found that response to be hugely unsatisfying, but didn’t know what to do about it. So I kept my eye on it, measured it, and over 10 years it never got worse. To be honest it sort of shook my faith in the quality of Ericsons a bit (which I know is heresy).

 

[Seth]

structures

Martin may be able to verify this, but it sounds like a cabinet attachment issue, and as PS says, not critical. Unlike the older vintage boats from the 70's and before, the new 32, 34, 38, etc, have the TAFG, which carries the structural loads, whereas in the older boats the furniture WAS structural, and this kind of thing would be quite serious.
From what I am hearing, the nonstructural cabinet may be moving slightly, but consistent with you observation of no hull flexing, you don't really have a serious problem. It could be fixed, as they say, but it will be more cosmetic than structural.
"Not to worry" is my take..Martin?
S

 

[u079721]

Not quite....

Actually it is not that the non-structual cabinet is moving - it is that the hull is flexing and the cabin sole drops away from under the cabinet. The hull, and the TAFG (which both my and Ted's boats have) is sagging, away from the cabinet, and the cabinet is left sort of hanging in the air. If it were just the cabinet flexing I would not have been so concerned - but it was the hull moving, which rather alarmed me.

In any case it wasn't like oil-canning, in that it just flexed once, after launch, as the hull settled into a new shape. So I wasn't worried about hull fatigue, but it still was a concern.

In fact, when I lost my job last year I briefly thought about saying the hell with it, selling my home and going cruising in my Ericson 38 for a year or two. But part of the reason I didn't was that I didn't really trust the boat, in part due to this hull settling.

 

[Martin King]

Does my hull need viagra?

I'd be more concerned if this boat did not have the grid, however ya
gotta expect that the hull is going to change shape in and out of the
water resulting in doors that don't close, weird gaps that appear and
the like. If it's a non structural part then I wouldn't worry too much
about it. Hey if you think Ericson's are bad in this regard, be glad you
don't own another popular brand of boat where in a particular model
the ends bend up like a banana every time you put on some backstay!

Martin
E31C (no grid)

 

[ted_reshetiloff]

Okay so I guess I am a little less worried now... At least my 38 is not the only one and it does not appear to be structural but it sure is diturbing to see. I agree that it appears as though the cabin sole is sinking away and I am left with a 3/4 inch gap. I guess I will monitor it and see if it get larger. Any thoughts on how to fix? Even if it ends up moving again when I haul I would rather not see the gap. Its rather unnerving and surely does make me question Ericsons integrity. I thought rather highly of the structural grid but if the hull is in fact flexing like it appears to be than that old grid aint all that great. I like to sail my boats pretty hard and if this is what happens well I don't know...

 

[Geoff Johnson]

There is no similar sagging on my 32-3. I inspected a 35-3 recently and was struck by how narrow the "stringers" in the grid were compared with my boat (you can see a photo og my grid in the "removal of glued down cabin sole") thread.

http://www.ericsonyachts.org/infoexchange/showthread.php?t=1526


Possibly, therefore, the grid on the larger boats was underdesigned.

 

[escapade]

The Gap

I also noticed the galley cabinet seperate from the sole on my E34 (1988) when I first purchased her. I found amoung other things that the rods that connect the rig attachment points to the TAFG were loose. Tightening them to snug +1 1/2 turns & making sure that the deck turnbuckle (between mast & deck) is good & snug before putting any rig or halyard tension on has cured the problem. My galley cabinet & stainless cabin-top support no longer seperate from the sole. Like Geoff, I've spent way too much time in the bowels of Ericson sailboats and even with their flaws I feel that they are amoung the best production boats ever built. Yes there were compromises made but as compared to some other boats they are minor.
Well, so much for my $.02 worth.
Have fun & sail fast
Bud E34 "Escapade"

 

[ted_reshetiloff]

Sailed the boat fairly hard yesterday and did not notice any change in the gap that opened. I am a lot less concerned about it now. When I replaced all of the standing rigging I did not make any adjustments to the rods below decks as they felt pretty tight. I also checked this when the boat was out of the water. As much of a PITA as it will be to pull all those cotter pins slack off the rig completely and check the tension on the rods I think I will give it a go. (Man that job could take a 12 pack...) I do need the rigging shop to shorten my forestay anyway so maybe I can get this all done at the same time. Thanks for the help here and I swear I will get some photos up soon. Been too busy sailing the boat. Wife is due with baby #2 August 11 so I am trying to get as much crusing and dinghy racing in as I can. BTW BIG BIG raft up party with several bands playing on the foredeck of 2 large powerboats along with mostly other sailboats from 28-48 feet this coming weekend in the West River near Annapolis MD. Sovereign Nation will be there should be a hoot all are welcome.

 

[u079721]

My experience too

Ted, that was my experience as well. The gap would form when the boat was launched, and the aft part of the hull seemed to settle down about that 3/4 of an inch. After that it was stable. We also sailed our boat very hard, and survived a storm or two on Lake Huron with 8 foot seas on overnight passages, and the gap never widened. I doubt you will see any difference or effect of adjusting the tie rods, as I adjusted mine, but still saw the gap. Partly that is because the tie rod anchors are several feet forward of the point where the gap is the worst, and also because the gap is down low, and the tie rod anchor points are at the sides of the hull. On a smaller hull there might be more of an effect.

The one thing I did notice was that the settling did take a few days after each launch. If I tuned the rigging right after launch I had to redo it a week later after the hull had reached equilibrium. After that it was stable.

 

[Geoff Johnson]

Seems to me that trying to use tension on the tie rods to lift the grid would be self-defeating because you would be putting more tension on the shrouds, which, in turn, would increase the downward force on the mast, in turn pushing the TFG down. You would also be transfering some of the load to the deck which is not meant to serve that function.

 

[ted_reshetiloff]

Yeah I am not certain that adjusting the rods will solve the problem or make it worse. Boats move in funny ways in the water and increasing or decreasing loads can have effects that are almost impossible to predict. All I was thinking here was that I never really checked the tune of those rods prior to tuning the rig other than to grab them when the rig was down and note that the felt snug, and after tuning I did not note the deck deflecting up. So my checking the tune of the rods was a seaparate concern from the hull flexing, but one that I thought could possibly contribute. Something I should probably check regardless. I would not propose trying to tighten the rods beyond the specs of 1.5 turns past snug with the rig unloaded. I hope to get some pictures today to post and get some ideas of what I can/should do about the cabinet/floor movement. Thanks guys.

 

[escapade]

the rod's

Ted
You are correct in believing that the rod's may or may not help your problem. My point was that it's an often neglected item and should be looked at along with everything else. They tend to form a tri-angle with the hull/deck joint, deck, hull, & hull/rod attachment point. If you change the length of any side of the tri-angle you affect the coresponding angles. By keeping the rods PROPERLY tensioned you will maintain the correct relationships between the deck/hull/TAFG. This way the rig loads are distriubited the BK intended them which is a good thing for your hull. The bottom of the hull sagging away from the cabinetery may be OK on the 38 design (as noted by other owners) but I don't blame you for being concerned. That type of thing scares me. Well I hope this clears up the tie-rod question.
Have fun & sail fast
Bud E34 "Escapade"

 

[ted_reshetiloff]

Pics finally

Finally took some shots of what I am seeing. Hopefully thisis what the others have seen. It is disconcerning to see and I not sure if there is anything that can be done. I am hoping to replace the cabing sole this winter and rebed the keel. I wonder if there is anything that canbe done then?

 

[u079721]

Yup - looks like mine

Yup, that's sort of what mine looked like. (Though my cabinets were oiled, so I didn't have that unfinished varnish line all along the cabin sole.)

What the engineer with whom I spoke at PS suggested was that it was possible to add a steel beam athwartships, anchored at the side edges, and then tied into the TAF in the middle, as a way to keep the hull from sagging. Sounds as if at a minimum you would have to remove or alter the cabinets and cabin sole.

Sounds like a LOT of work and expense to fix a problem that none of us are sure is more than cosmetic.

 

[ted_reshetiloff]

I Emailed Bruce King about this yesterday and he got back to me this morning. I include his response below.

Dear Ted,

I am sorry to hear you are having problems with your Ericson 38. It has been a long time and I am not certain if I can remember exactly how everything goes together on the Ericson 38. We designed the layout and geometry of the boat but the structure, including the "triaxial force grid", was engineered by Ericson and Dave Pedrick. As I recall, when the model change was made for the 200, the original force grid was utilized and the bulkheads around the galley were not structurally attached to the grid, as evidenced by the separation that you are experiencing. If I am correct regarding this, there might be some sort of separation between the grid and the hull. I am not certain how these two were joined, but I believe the grid was set inside the hull with fiberglass mat as an adhesive between the faying surfaces. There may be tab bonding along the grid edges as well. I would recommend that a surveyor ascertain whether the hull and grid are structurally attached or whether the grid is floating loose from the hull. If this were the case, or if it was never adequately attached from the beginning, I could see a case where the grid would sag over time.

With regard to your listing problem, as you know, this is a result of a laterial weight imbalance. If you do not wish to relocate equipment such as batteries, then ballast is the only solution. The ballast should be located to not only correct any listing problem but also any fore and aft trim problem. Without actually knowing the exact details, it is impossible to give you a specific location and amount of ballast. The optimal place would be not too far from amidships as weight in the ends is detrimental.

I hope this information is helpful.

Sincerely,
Bruce King

 

[Geoff Johnson]

Ted,

If you look at the photos from the thread on my replacing the cabin sole you can see clearly how the TFG was tabbed to the hull on the 35-3 and the 32-3 (at least in 1985). If you can pull up your sole, it should be easy enough to see if the the TFG has pulled away from the hull. However, I am a little puzzled by Bruce King's explanation, because if the TFG has broken away from the hull and the keel is being carried by the hull, the TFG would presumably suffer no deflection.


http://www.ericsonyachts.org/infoexchange/showthread.php?t=1526

 

[ted_reshetiloff]

I agree. Seems like if the grid was not attached to the hull then it would not be moving. I sincerely doubt the grid is not attached. The best answer to this issue i have gotten thus far came from another E-38 owner who emailed me:


We too experience this phenomenon when hauling out to the hard—the hull subsidates about ½ to 5/8 inch at the aft edge of the keel immediately beneath the galley sink (1989 38-200 so we have the transverse galley, older versions are laid out in a different orientation).


I asked Don Kohlman of Pacific Seacraft/formerly of Ericson Yachts about this and he said it is normal and not a problem. The issue is that the entire weight of the vessel compresses the hull structure when sitting on the keel. The tri-axial grid absorbs this movement and the cabinet is constructed to allow for this subsidation. In rough sea conditions, this compression would be spread over the entire hull. In a grounding, this compression would be distributed through the keel as in sitting on the hard.



If you look at the new Pacific Seacraft 38’s, there is a SS pipe from the end of the galley to the cabin top that is rigidly bolted to the galley cabinet and back-plated to the fiberglass structure in the cabin top. I asked if there was any structural benefit to this design (we considered modifying our boat to include this rod). He felt that it provided no additional benefit for subsidatation (the technical term for what we are talking about) but it was added for an additional handhold and other purposes.



In truth, I feel that there is some structural benefit to adding this pipe since that span of hull is the longest unsupported section of the boat. It does add about 5-10lbs and it is above the waterline. Plus you have to construct a heavy backplate in the cabin top to prevent the rod from pushing through in a knockdown. We are still considering doing it but have not yet decided.



I hope that helps, Don is usually very busy so I was very lucky to get a response on this issue.