Thanks Thanks:  0
Likes Likes:  0
Needs Pictures Needs Pictures:  0
Picture(s) thanks Picture(s) thanks:  0
Page 1 of 3 123 LastLast
Results 1 to 15 of 34
  1. #1
    Join Date
    Feb 2011
    Location
    San Diego, CA
    Posts
    236

    Default GIS repair recommendations

    Howdy,
    I bought a GIS thirdhand, and love the boat. It is lightly used, fits all my needs, and is kind on the eyes. I took it sailing in the ocean out of Oceanside Harbor in northern San Diego the other day. The conditions were a bit choppy with long swells in the 2-3 foot range. We did a bit of pounding working upwind. When I had brought the boat home, I noticed a dark area along the seam where the side panels meet, on both sides of the boat close to the bottom of the hull. On closer inspection, I noticed that the paint in that area had a fine crack along the seam. The darkness was I assume water that had worked in through the crack. I also assume that the crack formed from flexing the hull when working through the waves. When looking at the inside part of the seam, I noticed that the overlapping piece of plywood does not extend down all the way to the bracing wood (see photos to make up for my lack of correct terminology). I wonder if it should for maximum strength.

    I sealed the crack with urethane, but I'd prefer a more sturdy long term solution, as I like ocean sailing! Any ideas would help, and thanks in advance. I have attached a picture of the inside, and outside of the area where the cracks are.

  2. # ADS
    Google Adsense Advertisement
    Join Date
    Always
    Location
    Advertising world
    Posts
    Many





     
  3. #2
    Join Date
    Nov 2008
    Location
    Salem, Mass, USA & Co. Sligo, Ireland
    Age
    82
    Posts
    38

    Default

    While this is definitely an engineering question for MIK, I am curious...

    From the outside picture, can you confirm that the crack stops at the top of the stringer?

    Looks like there is f'glass on the exterior of the chine, but cannot see if the full height of the side is glassed as well, can you tell?

    Does the crack stop at the chine stringer?

    Do MIK's plans call for glassing the exterior in that area?
    ----
    Does look like a case study on why scarfs should be used, unless there's no glass where glass was called for by MIK.
    ----
    The small gap between the bottom of the butt block and the stringer shouldn't be the real problem IF the exterior surface, obviously overloaded in tension, was up to the loading, more likely the whole joint is not up to strength for the usage you're giving it.
    ----
    Without the plans in hand, and not knowing MIK's thoughts: I would plan on taking the sides down to bare ply and adding f'glass at least in the area where the side panels join (maybe 6" on each side of the crack).
    The fix would include routing out the crack completely, through to the butt block (skill saw) to the bare wood on both sides of the crack and first coating/soaking with straight epoxy before adding an extended structural filler.

    Will be interesting to hear MIK's assessment of whether the boat would be expected to survive your conditions -or- perhaps it was not built to his specs correctly.

  4. #3
    Join Date
    Aug 2010
    Location
    New Jersey, USA
    Posts
    767

    Default

    Quote Originally Posted by tommyboy View Post
    Do MIK's plans call for glassing the exterior in that area?
    They don't. The GIS plans call for glass tape on the chines only. Some builders ask about glassing the bottom and MIK normally concedes that rocky local conditions might warrant that precaution, but he's usually reluctant to agree due to the added weight. But there's been no discussion of a need to glass up the sides.

    Callsign222 put his Goat through some serious weather last summer along the coast of Maine. I'm not sure if he was hitting chop that warm beer describes, but he certainly did take on green water underway. His Goat is a touch un-fair at that joint--in the right light the seam shows distinctly--and he's made mention of addressing the cosmetic flaw. You may want to keep tabs on his findings to see if he's experience a structural issue too. I'll add the link to his thread shortly.

    Callsign's thread
    Callsign's blog

    Good luck and keep us all posted on your findings and progress.
    Dave
    StorerBoat Builder, Sailor, Enthusiast
    Dave's GIS Chronicles | Dave's Lugs'l Chronicles | Dave's StorerBoat Forum Thread

  5. #4
    Join Date
    Apr 2009
    Location
    Hunter Valley NSW
    Age
    69
    Posts
    1,759

    Default

    Yes, no glass is specified here. (My GIS has no glass at all as it’s not essential to the structural integrity)

    The butt strap not meeting the chinelog is not an issue. The butt strap join is very strong and not usually a problem if it is made correctly, so my guess is that this join was not made with epoxy glue. If it is epoxy, then perhaps the glue mixture wasn't thick enough. This would account for the joint flexing and opening up a crack which may have let moisture in. I’m assuming that the swelling is due to moisture, but it may be filler or glass tape. Does it feel spongy when you press your thumbnail into it?

    How is the joint on the other side? Any signs of the same swelling?

  6. #5
    Join Date
    Jun 2009
    Location
    New Hampshire
    Posts
    960

    Default

    HOLY COW I AM NOT ALONE THANK YOU WARM BEER!

    I feel somewhat redeemed now. YES.

    Here is a good picture of said problem.


    Yes, I have this same problem. It occurred first on the port side during construction, the starboard side stayed completely fair. It was a head scratcher. I sanded it down. Over the course of my season, the previously fair starboard side developed a bulge along the joint of the two pieces of ply used for the sides, identical to the one on of the port side.

    I chalked it up to crappy construction technique at the early stages of my gluing experience-- not enough glue evenly spread, not enough weight, perhaps not enough time before I stressed the pieces. But I do wonder about my plywood- I got some of the last batch of Shelman Okoume before they rolled over dead, maybe it was defective, maybe not....... Mik also hypothesized that it could be "epoxy creep" or something to that affect, I don't know either, because nothing else on the boat has moved one iota.

    The buttstrap does not have to meet the chinelog.

    I am about to embark on a repair mission on my boat. It will entail sanding, more sanding, maybe a Payson joint, and then repainting the hull. Stay tuned to my blog, and hopefully Mik will waltz in here and explain the Payson joint in detail.

    I too am Ocean-Goat-Sailor, so this concerns me as well, I definitely pounded the hell out of her last year, and this bulge creeped out as the season progressed.

    Oh, Congratulations on your new acquisition and welcome to the club!

    EDIT
    I do not have water infiltrating here. Yet. Everything is fine. I can see a small seam, but no crack, yet, and I plan to keep it that way.


  7. #6
    Join Date
    Jul 2005
    Location
    'Delaide, Australia
    Age
    65
    Posts
    8,138

    Default

    Howdy,

    We saw the red boat advertised some time ago - congratulations!

    It is often a bit hard to be really forensic about what causes what and also what is adequate construction.

    The crack in the butt strap could be the result of a collision or bump from inside or outside of the boat.

    The best type of proof that something is not adequate construction is a repeated pattern of failure in different boats. The Goat now has been around for about 15 years and some of the sailors here really push their boats hard. We haven't seen many structural failures of any type from any of the boats.

    So it is likely the main factor is that the gluing wasn't up to specification. But there could have been some damage or impact at some time.

    REPAIR
    I don't really like the Payson joint for boatbuilding because a lot of the people who propose its use don't scale the amount of glass to the amount of ply properly - but it really makes for a neat repair.

    The method is to use a sander to make a very shallow trench - usually less than one veneer thickness and lay a glass tape into the trench. The method was detailed when Koala dropped his Eureka Canoe and punched a hole in it.
    https://www.woodworkforums.com/f32/ho...ir-hole-74333/

    MIK

  8. #7
    Join Date
    Dec 2009
    Location
    Texas
    Posts
    319

    Default

    Welcome to the Goat Island Skiff family.

    I work up in Orange, California, but my GIS and family are back in Texas. Look in the Texas-GIS thread of this forum for what we did and are doing with our goat.

    My new work schedule has me working out here until the end of 2011. I will gladly drive down and look your GIS over. I still have not seen another GIS in person so I would love the opportunity to see one up close.

    I think the GIS is a great boat for southern Cal by the way.

  9. #8
    Join Date
    Feb 2011
    Location
    San Diego, CA
    Posts
    236

    Default

    Hey everyone,
    Thanks for the feedback and the welcome to the GIS club! I've read through pretty much all the GIS threads. Some of them took awhile, but definitely fun reading!

    After doing the research, I bought my boat off Craigslist in Klamath last year, and am enjoying it immensely. I had a fun time registering my boat with the California DMV, (my favorite part was the "alternative fuel technology tax"), and rigging the boat using the GIS rigging webpage.

    To answer your questions, my GIS has fiberglass on the bottom, wrapping up over the chines, and appears to end exactly where the cracks visibly start on both sides of the boat. They then extend about five inches upwards towards the gunwales. There appears to be no bulging at this time from water intake, the hull is not squishy, and the paint does not want to peal off. I'm hoping that a little internal strengthening will do the trick, combined with sealing the area from the outside

    I'm thinking of adding a couple of pieces of wood to overlap the bottom of the buttstraps, and cover the open seam area just above the chinelogs. Do you think this will help? Any tricks to epoxying these in place?

    John, yes, definitely a good boat for San Diego. No slip, fits in the garage, sails great, looks great, and you can row it. We don't have squalls here to speak of. The wind is consistent and predictable, though a bit on the light side. I've been wondering why there are not more small boats of this sort out there on a sunny weekend. I think the answer is the DMV ), and that most daysailers are either too small (laser), are not designed for rowing (all of them), or take over half an hour just to set the mast and stays (harpoon 5.2).

    It would be fun to have you down, and show you the boat. I'm still trying to figure out the best upwind tweaking for my dw vertical cut sail, (I think callsign had this issue as well), maybe you can help!

  10. #9
    Join Date
    Feb 2011
    Location
    San Diego, CA
    Posts
    236

    Default

    I've been thinking about what Mik said with regards to a collision causing damage. I did not have a collision, but it got me wondering if you can stress the butt of the buttstrap joint in other ways, such as when the boat is on the trailer. For my trailer, the hull is supported a few feet on either side of the buttstrap so:
    (1) climbing into the boat on the trailer and standing in the area of the buttstrap should load that joint with a good bit of weight.
    (2) driving over a big bump, like a speedbump, at a speed that might "hop" the trailer might load that joint.

    Maybe it is not a bad idea to extend the chine fiberglass a bit (six inches) towards the gunwales to reinforce this area?

    Here's a couple of photos. In one I'm checking out the sail with the lower batten removed and loose outhaul. I did not like this configuration, and have stuck the lower batten back in, and tightened the outhaul. The other is of my son learning what "come up", and "fall off means".

  11. #10
    Join Date
    Feb 2011
    Location
    San Diego, CA
    Posts
    236

    Default photos for the last post


  12. #11
    Join Date
    Jun 2009
    Location
    New Hampshire
    Posts
    960

    Default

    Maybe. A good theory, but maybe. Really tough to tell, I would think. The chine and the gunwale with the inwale stiffening system really cranks this whole area in nice and tight.

    One thing I'm wondering-- I took a big spill in my boat one day (falling, not capsizing) and I almost put my foot through the ply near BH2. It actually seriously checked the exterior of the ply in this spot. Bruce (woodeneye) asked me to check the area around BH2 because I could have separated the hull there. No dice. However, I may have loosened the bad glue job back at the joint instead, but didn't see it since for me it's light-sensitive, as in, I need a sun low on the horizon to cast a shadow just so.

    Don't know. Lots of theories. The buttstrap is such a huge gluing area, if glued right, in combo with the chine and inwale and gunwale, nothing should really move.

  13. #12
    Join Date
    Jun 2009
    Location
    New Hampshire
    Posts
    960

    Default

    You have a picture of the boat, from a distance, so we can see it? I don't think this was the one for sale in San Francisco, is it? You said Klamath? I'd love to see it. EDIT I missed the craigslist ad that was posted here, apparently. I think the one in SF was solid red, Mik, no stripe.

    BTW, I don't think standing in the boat when it's on the trailer is a good idea, at all, ever. But I'm paranoid about these things.

  14. #13
    Join Date
    Jul 2005
    Location
    'Delaide, Australia
    Age
    65
    Posts
    8,138

    Default

    Howdy,

    My guess is that it either was one time damage or the gluing job wasn't up to spec. Just because this type of joint has been fine for so many other boats over the years - not just my designs either.

    If it is from an impact then it has damaged the buttstrap bond slightly. But the Payson joint type repair will fix it permanently. You could just dry it out and sand and put some epoxy over the area.

    Have a close look at the crack and lean on the join from outside the boat and inside the boat and see if the crack changes width. If with hard normal pressure there isn't a change you could just let it dry out, sand and put three coats of epoxy on it wet on wet.

    Allow it to cure, light sand and some sort of undercoat or primer or paint over the top to protect the epoxy from UV and sail out the rest of the season.

    If the seam moves then you will need the glass tape type repair I mentioned, but just undercoat over the top and go sailing for the season. Worry about the cosmetics later.

    MIK

  15. #14
    Join Date
    Apr 2009
    Location
    Hunter Valley NSW
    Age
    69
    Posts
    1,759

    Default

    Yep, second the not standing in the boat on its trailer, or on the shore for that matter. That would be very bad for a boat of this light a construction, and likely to cause some damage. However, in this case I don't think that's the cause of the side joint failure.

    Another possible cause not yet mentioned is turning the boat on its side to drain when too full of water, especially if the surface is uneven or there was an object on the beach that would put pressure on the joint. I went to do this once, and quickly realised that the weight of the water in the hull was too much, so bailed most of it out first.

  16. #15
    Join Date
    Dec 2009
    Location
    Texas
    Posts
    319

    Default

    This is how my trailer supports our GIS.

    I do not get in the boat while it is on the trailer because I weigh just over 210 pounds. If I walk in the boat while on the ground I step directly over the bottom runners.

    Woodeneye may of touched on the cause when he mentioned rolling the boat over. If the gunnel wood type is a soft or flexible wood the hull could deform enough to flex the butt strap. If the butt strap was not bonded well, rolling the boat over on it's side could work the butt strap loose.

    The other picture is to show that the butt strap can be very carefully chiseled away if need be. I cut mine long to get them right next to the chine without any gap.

Page 1 of 3 123 LastLast

Similar Threads

  1. Any Recommendations for new DGH
    By cathymac1 in forum PLUMBING, ELECTRICAL, HEATING, COOLING, etc
    Replies: 2
    Last Post: 9th April 2008, 02:05 PM
  2. Air gun recommendations pls
    By pomp in forum HAND TOOLS - POWERED
    Replies: 12
    Last Post: 16th March 2008, 12:33 PM
  3. Recommendations??
    By Krunchynuts in forum SCROLLERS FORUM
    Replies: 1
    Last Post: 5th December 2007, 05:15 PM
  4. Recommendations Please
    By DPB in forum BANDSAWS
    Replies: 3
    Last Post: 16th October 2001, 11:46 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •