Leaking Garboard Plank

[RIWATER]

Launching our boat each season is always an exciting experience. I have to run two pumps to keep her floating, but after a good nine hours of swelling she stops leaking enough to where the bilge pump is enough to keep up. Mid summer her pump kicks on every 12-20 hours. I know she is not the tightest boat but all in all not too bad.

When I sail her in heavy conditions she will leak a fair amount. I had the opportunity go below in a race this summer and observe the leaking and it looks like most of the water is coming beneath the Garboard. The boat is a Concordia Yawl built in 1951.

I have read about another Concordia that used a system to tie the floor near the mast step to the chain plates to prevent the boat from flexing thereby reducing the leak along the garboard.

My question to the group is has anyone used this type of fix on a boat to prevent the flexing of a boat? I guess there would have to be some engineering to make this work.

Any info would be helpful.

Thanks
Dave

[Ian McColgin]

Many older sailboats have this issue. On Goblin - my old Alden 43' schooner built in the late 20's - someone in the 60's or so tried to fix this at the foremast with tie rods from the partners to the step. It helped but was not attempted at the mainmast as the trunk cabin there would not have supported such a strain without a compression post and it was feared it would lead to hogging.

I played with the idea of extending the chainplates but figured, after much consult at Benjamine and Gannon that I ought to first attend to the frame hood ends and make sure the garboards were well fastened. That massive job never got going, so I just pumped a lot after a hard beat.

Nat and Ross were not really sanguine about the utility of chainplate extension, certainly not as an alternative to popping the garboards and getting the frames happy. I don't know for sure if this is a general rule or if it only applied to Goblin as they saw her.

Assuming a proper chainplate pattern, which your boat has or at least had as built, a bit of frame repair and perhaps extending and beefing up the mast step are the likely best solution.

Whatever you do, make sure that you get the garboard fastened to good wood first.

[RIWATER]

I re-fastened the boat two years ago and it seems to me that I had solid wood to secure the new screws along the garboard. My mast step was beefed up too approximately five years ago. I know I have flexing going on in the area of the mast as my paint job is starting to fail only in that area. (hence new paint job every three years) The seams have worked a little bit. I have seen this in other boats.

Well once my budget will allow I guess I will have to bring her over to Concordia and see if they can help.

Thanks
Dave

[felthamscruiser]

when screwing the garboard plank do you put them at the lowest point on the plank or in the centre??

[rooster]

I worked on some IC class boats in S.F a while back.Alot of them had tie rods running from the mast step up and out to the chain plates.It was o.k for a race boat but might be a problem in a cruising boat. I don't think I would like tie rods running diagonaly thru the cabin.:rolleyes: rooster

[sawcutmill]

Call Jim Titus at Mount Hope Boatworks. His shop is located on Third Street in Newport, right off the Rotary, and he specializes in that sort of Repair, as well as much other structural work. His shop did Dorade 2 years ago, and now has just completed a 1926 Alden schooner, and is in the process of rebuilding the 80' Black Knight, some 90 pairs of frames, new planking etc....both .at the Newport shipyard.
Seriously call him, he is very agreeable and willing to get you the best your boat deserves.

[Dan McCosh]

Using tie rods from the mast step to the chain plates does work, but it is not that simple a solution. The tie rods take some of the compression load on the step, but also produce compression at the mast partners--effectively squeezing the hull together. This means something to take the transverse compression load also is needed, and a tension rod from the deck to the step as well. This does not help hull bending much, however, which needs a relatively long, stiff mast step that distributes the load fore and aft as well. What you aim for is a kind of metal truss that supports the rigging loads.

[Hank Bornhofft]

Dave, "Magic" is a Concordia 41 and I have installed a mast step tie rod system and it helps alot. She would leak when beating to windward but stop off the wind or on the mooring where the bilge is bone dry. These boats will always flex driven hard to weather but settle down when at ease with no resulting damage. My direct mail is yachtmagic@comcast.net-I don't regularly monitor the forum.
Hank Bornhofft

[felthamscruiser]

im not familiar with this tie rod system any pictures of this set up would help a great deal

[Jay Greer]

On my Common Sense Sloops, I designed a structural bulk head just fwrd. of the mast. This gives a supporting diaphram to panting of the section in way of the mast. In addition there is a tie rod from the deck through the mast step, just fwrd of the mast. Lastely, the upper shroud chain plate has an extension down the inside of the the hull that wraps and connects to a bronze plate saddle under the mast step. I have found this system to all but eliminate garboard and fore foot scarf working in this area. The boats do not leak on the wind or off of it.
Jay

[peter baker]

Hi Riwater

My boat has some arrangement of what you are thinking of.
It has been done about ten or more years ago.
It’s quite a pike of engineering but basically its some kind of a cage arrangement connected to the mast step, which has been tied in with a steel frame. The cage also connects to the chainplates, which are interconnected with each other through a big backing plate arrangement. I could go and get you some pics some time this week to make it a bit more visual.
As to how good it works I cant really tell you any thing, as I have never had her under sail so far. Bought her as a project boat and didn’t quite know what I was in for, so three years later I'm still a good way of. It's a Charles Nicholson south coast one design
26 feet.