Is Wobble of 2 to 3 Inches in Cal 28 Keel Cause for Concern?

Another Cal 28 flush desk owner called with the above inquiry. He's a member, but computer in the shop and information needed while on the hard. Crane operator called in a panic over a 2 to 3 inch side to side wobble in the keel. The owner's fiberglass guy looked at the boat and said he saw no need for concern, and that some boats just wobbled. There is no visible damage to the keel. No cracks of any kind. No stress fractures anywhere. I told the owner that Charlie and many others could better answer his question, and that I would relay the information once received. Any thoughts? Thanks. Bruce Stirling

blockquote, div.yahoo_quoted { margin-left: 0 !important; border-left:1px #715FFA solid !important; padding-left:1ex !important; background-color:white !important; } Sorry to just make a statement with nothing to back it up, but that can't be normal or safe. I wonder if outside damage was repaired but structural damage not fixed. There's a YouTube video I believe it's sailing uma or something like that. They had wobble with structural damage. Different boat but maybe worth watching. On the patio with a cold beer and that's my 2 cents. Sent from Yahoo Mail for iPhone On Monday, June 13, 2016, 6:48 PM, ca… [at] yahoo.com [Cal_Boats] <Ca… [at] yahoogroups.com> wrote: Another Cal 28 flush desk owner called with the above inquiry. He's a member, but computer in the shop and information needed while on the hard. Crane operator called in a panic over a 2 to 3 inch side to side wobble in the keel. The owner's fiberglass guy looked at the boat and said he saw no need for concern, and that some boats just wobbled. There is no visible damage to the keel. No cracks of any kind. No stress fractures anywhere. I told the owner that Charlie and many others could better answer his question, and that I would relay the information once received. Any thoughts? Thanks. Bruce Stirling -- {border:1px solid #d8d8d8;font-family:Arial;margin:10px 0;padding:0 10px;} hr {border:1px solid #d8d8d8;} #hd {color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px 0;} #ads {margin-bottom:10px;} .ad {padding:0 0;} .ad p {margin:0;} .ad a {color:#0000ff;text-decoration:none;} {font-family:Arial;} #hd {margin:10px 0px;font-weight:700;font-size:78%;line-height:122%;} .ad {margin-bottom:10px;padding:0 0;}#actions {font-family:Verdana;font-size:11px;padding:10px 0;}#activity {background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}#activity span {font-weight:700;}#activity span:first-child {text-transform:uppercase;}#activity span a {color:#5085b6;text-decoration:none;}#activity span span {color:#ff7900;}#activity span .underline {text-decoration:underline;}.attach {clear:both;display:table;font-family:Arial;font-size:12px;padding:10px 0;width:400px;}.attach div a {text-decoration:none;}.attach img {border:none;padding-right:5px;}.attach label {display:block;margin-bottom:5px;}.attach label a {text-decoration:none;}blockquote {margin:0 0 0 4px;}.bold {font-family:Arial;font-size:13px;font-weight:700;}.bold a {text-decoration:none;}dd.last p a {font-family:Verdana;font-weight:700;}dd.last p span {margin-right:10px;font-family:Verdana;font-weight:700;}dd.last p span.yshortcuts {margin-right:0;}div.attach-table div div a {text-decoration:none;}div.attach-table {width:400px;}div.file-title a, div.file-title a:active, div.file-title a:hover, div.file-title a:visited {text-decoration:none;}div.photo-title a, div.photo-title a:active, div.photo-title a:hover, div.photo-title a:visited {text-decoration:none;}div p a span.yshortcuts {font-family:Verdana;font-size:10px;font-weight:normal;}.green {color:#628c2a;}.MsoNormal {margin:0 0 0 0;}o {font-size:0;}#photos div {float:left;width:72px;}#photos div div {border:1px solid #666666;height:62px;overflow:hidden;width:62px;}#photos div label {color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}#reco-category {font-size:77%;}#reco-desc {font-size:77%;}.replbq {margin:4px;} div a:first-child {margin-right:2px;padding-right:5px;} {font-size:13px;font-family:Arial, helvetica, clean, sans-serif;} table {font-size:inherit;font:100%;} select, input, textarea {font:99% Arial, Helvetica, clean, sans-serif;} pre, code {font:115% monospace;} * {line-height:1.22em;} #logo {padding-bottom:10px;} p a {font-family:Verdana;} p#attach-count span {color:#1E66AE;font-weight:700;} #reco-head {color:#ff7900;font-weight:700;} {margin-bottom:20px;padding:0px;} #ov li a {font-size:130%;text-decoration:none;} #ov li {font-size:77%;list-style-type:square;padding:6px 0;} #ov ul {margin:0;padding:0 0 0 8px;} {font-family:Georgia;} p {margin:0 0 1em 0;} tt {font-size:120%;} ul li:last-child {border-right:none !important;}

I just watched all 11 videos re the restoration of a donated Cal 40. Episode 6 talks about "keel wag," and mentioned it was a common finding. Based on what I heard, it sounds fairly normal and nothing to get too upset about, assuming no structural issues. See, https://youtu.be/-VQMvskYXCk?list=PLNvA533t8aT4yDqt7xNJVl5il42oscn6- https://youtu.be/-VQMvskYXCk?list=PLNvA533t8aT4yDqt7xNJVl5il42oscn6-

All I can say is mine does more then that on my 29. If you sail in confused seas that are high, maybe cause for concern. if you sail in moderate or consistent seas, probably wouldn't worry about it. No can say definitively without seeing it, but there are many out there that wobble. The laminate is getting weaker w age. as it flexes more and more, micro cracks begin to allow water into the laminate. The water eventually degrades the resin and the laminate eventually will be resin starved. Sounds scary but the process seems to take a very long time. Here is an except and link... http://www.zahnisers.com/wp-content/uploads/2014/01/Repair-Blisters.pdf The effects of hydrolysis on the resin, however, are of more concern than blisters. The hydrolysis process softens, weakens and removes the resin from the laminate, thus reduc ing the rigidity of the laminate. As rigidity is reduced, the amount of flex experienced in portions of the bottom increases. With increased flexure comes increased risk of fatigue failure. Most yacht hulls have a considerable safety factor built into the construction, leaving quite a bit of room for deterioration. These safety margins, however, vary widely and are constantly under pressure to be reduced in the name of performance. If a hull is of cored construction, serious structural damage can occur quite quickly. Large scale core saturatio n is largely irreparable at a reasonable cost. It should be noted that the presence of water alone in a glass laminate, even when no hydrolysis damage has been done, significantly decreases laminate's resistance to structural fatigue. You might ask how long might it take for the deterioration to become a structural concern? This cannot be answered categorically. The truth is, to date, little research has been done to establish deterioration rates and quantitative strength losses over time. Complicating fac tors include the thickness of the hull structure, the intended use, the surrounding water temperature, the degree of water absorption, the degree of blistering and hydrolysis, the age of the laminate at the time of blister onset, the materials used in cons truction and the design of the vessel all have a bearing on the rate of deterioration and the effect of deterioration on the structure. In 1991, Zahniser's commissioned Comtex Laboratories to analyze the physical properties of laminate panels removed from the bottom of Gulfstar 50. The laminate was highly hydrolyzed. The bottom was clearly deforming from water pressure due to immersion suggesting low laminate rigidity.. Test results on these panels showed a fifty percent reduction in rigidity from the new condition. Tensile strength, however, was not greatly affected. The loss of rigidity is significant as the bottom will flex ("oil can") more over bulkheads and other hard spots and eventual time to fatigue failure will be shorter. We also tested a "repaire d" panel, using the methods discussed in this paper and achieved rigidity approximately 130% of the theoretical new condition. East coast cal 29 sailor On Mon, Jun 13, 2016 at 6:48 PM, ca… [at] yahoo.com [Cal_Boats] < Ca… [at] yahoogroups.com> wrote: > > > Another Cal 28 flush desk owner called with the above inquiry. He's a > member, but computer in the shop and information needed while on the hard. > > > Crane operator called in a panic over a 2 to 3 inch side to side wobble in > the keel. The owner's fiberglass guy looked at the boat and said he saw no > need for concern, and that some boats just wobbled. There is no visible > damage to the keel. No cracks of any kind. No stress fractures anywhere. > > > I told the owner that Charlie and many others could better answer his > question, and that I would relay the information once received. > > > Any thoughts? Thanks. > > > Bruce Stirling > > >

On 6/14/2016 3:26 PM, 'sailor7312 .' sa… [at] gmail.com [Cal_Boats] wrote: > > Theeffects of hydrolysis on the resin, however, are > of more concern than blisters. The hydrolysis process softens, weakens > and removes the resin > from the laminate, thus reduc > ing the rigidity of the laminate. That explains what happened to my other boat, built to pretty high standards in 1961 (early fiberglass). A two years ago I discovered a large amount of water in the bilge. Eventually I traced it to a tube between hull and cockpit sole in which the rudder stock ran. When the boat was hauled for the season, I discovered that the resin had just disappeared, leaving fiberglass mat. That stuff isn't too waterproof! The fix was simple: add epoxy, add another layer of fiberglass (cloth), add more epoxy. Problem solved. But apparently it would have been hydrolysis that evaporated the resin. Maybe the tubes were made separately; maybe some worker in the Netherlands wasn't attentive to resin and hardener ratios that day; maybe it's bad luck. But the hull seems to be durable, luckily. Chris Campbell

My understanding is back in the day the ratios were not well controlled. Also, the engineering was fairly crude, so for the most part, hulls were way over built. if they were not, then we would be seeing far more failures. I have seen the resin starved look in some laminates and until I began to understand hydrolysis, I always thought it was sloppy layups. I have seen small boat hulls where water was left in them and they just turned to mush. The key is be knowledgeable but not fearful. Recognize that the boats are getting older and keep an eye on some of the critical areas. My 29 is one ugly boat, in desperate need of attention, but she sails well, I just don't pull on the backstay as hard as I might like. Some day I plan to fix all that ails her, but for now, I am just happy to have what I have. East Coast Cal 29 sailor On Tue, Jun 14, 2016 at 4:50 PM, ccampbell <cc… [at] lsnm.org> wrote: > > > On 6/14/2016 3:26 PM, 'sailor7312 .' sa… [at] gmail.com [Cal_Boats] > wrote: > > > The effects of hydrolysis on the resin, however, are > of more concern than blisters. The hydrolysis process softens, weakens and > removes the resin > from the laminate, thus reduc > ing the rigidity of the laminate. > > > That explains what happened to my other boat, built to pretty high > standards in 1961 (early fiberglass). A two years ago I discovered a large > amount of water in the bilge. Eventually I traced it to a tube between > hull and cockpit sole in which the rudder stock ran. When the boat was > hauled for the season, I discovered that the resin had just disappeared, > leaving fiberglass mat. That stuff isn't too waterproof! > > The fix was simple: add epoxy, add another layer of fiberglass (cloth), > add more epoxy. Problem solved. But apparently it would have been > hydrolysis that evaporated the resin. Maybe the tubes were made > separately; maybe some worker in the Netherlands wasn't attentive to resin > and hardener ratios that day; maybe it's bad luck. But the hull seems to > be durable, luckily. > > Chris Campbell >

Just noticed the recent coverage on this issue originally posted on May 24 by David Field re his Cal 27. Sorry for not checking archives first. Thanks to all who replied. Adding link here to David's post to make part of this one. https://groups.yahoo.com/neo/groups/Cal_Boats/conversations/topics/41480?reverse=1 https://groups.yahoo.com/neo/groups/Cal_Boats/conversations/topics/41480?reverse=1