My 25D has a pre-release dimple on the port side of the hull and I am hauling this Oct to fix. Anyone out there have a similar experience that could lend some information. It should be an easy fix by removing the through-hull under the galley, fashion an oversized plate to suspend some weight from this area and hope to relax the dimple. I can then glass in an athwartships wood beam to hold the shape. Sound about right?
Tom McClarren
25D #4 "Caile"
Pre-release dimple
Moderator: Jim Walsh
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Ken Coit
OK, I can't stand it,
what is a "pre-release dimple?"
I have no clue as to how to fix it, but I'd sure like to recognize one the next time I see one.
Thanks.
Keep on sailing,
Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC
parfaitNOSPAM@nc.rr.com
I have no clue as to how to fix it, but I'd sure like to recognize one the next time I see one.
Thanks.
Keep on sailing,
Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC
Tom McC wrote: My 25D has a pre-release dimple on the port side of the hull and I am hauling this Oct to fix. Anyone out there have a similar experience that could lend some information. It should be an easy fix by removing the through-hull under the galley, fashion an oversized plate to suspend some weight from this area and hope to relax the dimple. I can then glass in an athwartships wood beam to hold the shape. Sound about right?
Tom McClarren
25D #4 "Caile"
parfaitNOSPAM@nc.rr.com
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Smiley
Re: OK, I can't stand it,
Maybe its a dent in the hull that appears just before you smileKen Coit wrote: what is a "pre-release dimple?"
Ken Coit wrote: I have no clue as to how to fix it, but I'd sure like to recognize one the next time I see one.
Thanks.
Keep on sailing,
Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC
Tom McC wrote: My 25D has a pre-release dimple on the port side of the hull and I am hauling this Oct to fix. Anyone out there have a similar experience that could lend some information. It should be an easy fix by removing the through-hull under the galley, fashion an oversized plate to suspend some weight from this area and hope to relax the dimple. I can then glass in an athwartships wood beam to hold the shape. Sound about right?
Tom McClarren
25D #4 "Caile"
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Tom McC
Re: OK, I can't stand it,
A pre-release dimple is an indentation on the hull. It can vary in size and is caused by the premature release of the hull in that area as the rest of the layup is still bound in the mold. It is not a structural issue but more of a cosmetic one. Luckily for me it is at the aft part of the hull where the layup is not as robust as it is in the forward section, and there is a through hull in the area of this indentation. I am hoping that by hanging some weight (say 50 to 100 lbs) this will relax the area and allow me to glass in a member inside the hull to hold the shape.
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John R.
Re: OK, I can't stand it,
Tom,
I have worked for a few different builders in the past and I have never heard of the term "pre release dimple" but I do understand what you are talking about in so far as a concave anomaly in the hull fairness is concerned. That isn't all that rare in hull production work. Usually non releasing sticking layups in the mold create the majority of problems. In virtually every case of a hull recess that I have ever witnessed the problem usually occured in appendage areas which are difficult to lay up unless it is a two piece hull. those cases were very rare. In every case the usual remedy was to simply fill and fair if the defect was shallow in nature. If it was of any significant depth the hulls were removed from the assembly line and either cut up with a chain saw or auctioned off at a later date. I can't say that I've ever seen a CD with a hull deformity like you mention that was obviously not corrected by the factory. Something doesn't sound right with what you are describing. Are you absolutely certain this hull was never damaged in some way. If I were you I would do a very close examination and sounding of the immediate area on the hull and hire a skilled surveyor for another opinion in case you are not positive about your examination results.
I have worked for a few different builders in the past and I have never heard of the term "pre release dimple" but I do understand what you are talking about in so far as a concave anomaly in the hull fairness is concerned. That isn't all that rare in hull production work. Usually non releasing sticking layups in the mold create the majority of problems. In virtually every case of a hull recess that I have ever witnessed the problem usually occured in appendage areas which are difficult to lay up unless it is a two piece hull. those cases were very rare. In every case the usual remedy was to simply fill and fair if the defect was shallow in nature. If it was of any significant depth the hulls were removed from the assembly line and either cut up with a chain saw or auctioned off at a later date. I can't say that I've ever seen a CD with a hull deformity like you mention that was obviously not corrected by the factory. Something doesn't sound right with what you are describing. Are you absolutely certain this hull was never damaged in some way. If I were you I would do a very close examination and sounding of the immediate area on the hull and hire a skilled surveyor for another opinion in case you are not positive about your examination results.
Tom McC wrote: A pre-release dimple is an indentation on the hull. It can vary in size and is caused by the premature release of the hull in that area as the rest of the layup is still bound in the mold. It is not a structural issue but more of a cosmetic one. Luckily for me it is at the aft part of the hull where the layup is not as robust as it is in the forward section, and there is a through hull in the area of this indentation. I am hoping that by hanging some weight (say 50 to 100 lbs) this will relax the area and allow me to glass in a member inside the hull to hold the shape.
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Tom McC
Re: OK, I can't stand it,
Thanks for the reply. I have had the boat surveyed proir to purchase. I did have a tough time coming to grips with this issue but the price was such that I couldn't refuse the deal. The surveyor has a long association with the Gugeon brothers (West System) and is somewhat of a subject matter expert in these matters. He was their go to guy in this area and I trust him. The surveyor did not discover any damage or repair in this area that would lead me to think it was struck. I agree that that typically the hull would not have made it to the "show room", which leads me to believe that it was probably filled and faired and for some reason taken down to original finish during perhaps an aggressive bottom sanding by the previous owner. In any event, the fix was reccommended by the surveyor and it is in good enough shape to insure.
Wish me luck.
Tom McC
25D #4 "Caile"
Wish me luck.
Tom McC
25D #4 "Caile"
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John R.
Re: OK, I can't stand it,
Tom,
You clarified to me in the latest posting that the recess is below the waterline which I overlooked in your initial post. Since you had a surveyor do a complete inspection and he/she found no evidence of previous impact or other damage I strongly believe what you are faced with is a depression made from a boat stand support that occured when the boat was incorrectly supported by having the hull weight on the stand rather than on the keel or that the boat stand pad had been overly tightened against the hull, which is not that rare of a situation. When a boat is on boatstands and the weight is supported by the keel on top of a couple heavy timbers the stands should be in position to afford lateral support to keep the boat from tipping over. The stand pads should be tightened up against the hull only to a point where the pad can still be slightly moved (rotated snugly). Any further tightening of the pad against the hull beyond that point and you are asking for trouble. My belief is that those pads were incorrectly put in place under your boat at one time and it was probably stored that way too long and that created the permanent deflection in the hull. As long as you and surveyor find no sign of structural weakness in that area then all you need do is fair the depression in and use a long board to get the contour correct, you should also use a batten to help guide you to regaining the correct contour. If the recess is quite deep you may need to do a little glass lay up, ask the surveyor if you aren't sure. Good luck.
You clarified to me in the latest posting that the recess is below the waterline which I overlooked in your initial post. Since you had a surveyor do a complete inspection and he/she found no evidence of previous impact or other damage I strongly believe what you are faced with is a depression made from a boat stand support that occured when the boat was incorrectly supported by having the hull weight on the stand rather than on the keel or that the boat stand pad had been overly tightened against the hull, which is not that rare of a situation. When a boat is on boatstands and the weight is supported by the keel on top of a couple heavy timbers the stands should be in position to afford lateral support to keep the boat from tipping over. The stand pads should be tightened up against the hull only to a point where the pad can still be slightly moved (rotated snugly). Any further tightening of the pad against the hull beyond that point and you are asking for trouble. My belief is that those pads were incorrectly put in place under your boat at one time and it was probably stored that way too long and that created the permanent deflection in the hull. As long as you and surveyor find no sign of structural weakness in that area then all you need do is fair the depression in and use a long board to get the contour correct, you should also use a batten to help guide you to regaining the correct contour. If the recess is quite deep you may need to do a little glass lay up, ask the surveyor if you aren't sure. Good luck.
Tom McC wrote: Thanks for the reply. I have had the boat surveyed proir to purchase. I did have a tough time coming to grips with this issue but the price was such that I couldn't refuse the deal. The surveyor has a long association with the Gugeon brothers (West System) and is somewhat of a subject matter expert in these matters. He was their go to guy in this area and I trust him. The surveyor did not discover any damage or repair in this area that would lead me to think it was struck. I agree that that typically the hull would not have made it to the "show room", which leads me to believe that it was probably filled and faired and for some reason taken down to original finish during perhaps an aggressive bottom sanding by the previous owner. In any event, the fix was reccommended by the surveyor and it is in good enough shape to insure.
Wish me luck.
Tom McC
25D #4 "Caile"
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Tom McC
Re: OK, I can't stand it,
John, I agree. This is more likely the reason for the deflection and I believe it can be repaired fairly easily. Thank you for your input.
Tom McC
25D #4 "Caile"
Tom McC
25D #4 "Caile"
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Kurt
Improper storage can leave dents in the hull
When I purchased my CD26 back in 1992, she had been out of the water for several years. The storage cradle had slowly sagged over time putting six dents in the hull...maybe a 1/4" to 3/8" deep. I used this as a bargaining chip to negotiate a lower price. Well, much to my surprise, after a couple years...the dents disappeared! Fiberglass boats are amazing at times.
kjlgpw@aol.com
kjlgpw@aol.com
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John Nuttall
You may need to use a DENSE fairing material if...
......the area to be faired is penetrated by the thru hull.
If you build up a significant thickness of fairing material you need to make sure it it strong enough to withstand the compression load when you tighten down the re-installed thru hull. Typical fairing materials are designed to be easy to sand, and are not suitable for a load.
Also, if the thickness of the material is great enough, you may not be able to get enough thread into the seacock. You should check that before you start.
Personally, I would take the approach that if it ain't broke, don't fix it.
Unless you think that the situation has the potential to sink your boat (say because panel flex in the area of the thru hull due to delamination and weakness in the panel section) then why mess with it? It is going to be more trouble than it's worth. You will not see any signifigant performance gain by fairing it out.
However if you do proceed, you are required to take and post lots of digital pictures of your progress so we can cheer you on !!! (Just kidding!)
Best of Luck
John
s/v Aimless
CD31 #28
Oriental, NC
If you build up a significant thickness of fairing material you need to make sure it it strong enough to withstand the compression load when you tighten down the re-installed thru hull. Typical fairing materials are designed to be easy to sand, and are not suitable for a load.
Also, if the thickness of the material is great enough, you may not be able to get enough thread into the seacock. You should check that before you start.
Personally, I would take the approach that if it ain't broke, don't fix it.
Unless you think that the situation has the potential to sink your boat (say because panel flex in the area of the thru hull due to delamination and weakness in the panel section) then why mess with it? It is going to be more trouble than it's worth. You will not see any signifigant performance gain by fairing it out.
However if you do proceed, you are required to take and post lots of digital pictures of your progress so we can cheer you on !!! (Just kidding!)
Best of Luck
John
s/v Aimless
CD31 #28
Oriental, NC
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Tom McC
Re: You may need to use a DENSE fairing material if...
John, Again it appears we are on the same wave length. The integrity of the hull in that area has not been comprimised. This is mearly a cosmetic issue and will not affect the performance of the boat. The only fix I am going to try is to see if I can SLOWLY relax this dimple by applying some weight directly to that area and let gravity do its thing. Then I would glass in that athwartships beam inside the hull to hold the shape. Even if I can get close to the original shape and fair in where needed. Good advise about the through hull. I will chronicle my progress with some pics and post them. Thanks again.
Tom McClarren
25D #4 "Caile"
Solomons Maryland
Tom McClarren
25D #4 "Caile"
Solomons Maryland