Shellback troubleshooting

[Clinton B Chase]

Hello Shellback builders:

Did anyone find the fact that the bottom panel is a little wider (up to 1/4") than the bottom facets on the molds to be a problem? The lofted widths for the bottom panel are actually wider than the lofted widths for the molds. Is this deliberate? Seems like it would not allow the garboard to lie on the mold flush and meet the bevel on the bottom panel flush. The solution was obvious: I have remarked the bottom panel and will rebatten it and trim it to a new fair line that is closer to the molds. Was just curious if others found this discrepency and if they worried about it. In hindsight I rememember this occurring on my small Nutshell, too, but didn't think anything of it; indeed it was tricky to plane the bevel with the bottom panel sticking out from the mold.

Cheers,
Clint

[willmarsh3]

Hi, I built a Shellback dinghy back in 1997 or so as I mentioned on previous threads. I'm extremely happy with mine.

What I did was to loft the bottom per the plans so as to keep the batten curve on the inside of the boat. After permanently mounting it to the stem, transom, amidships frame and moulds I ran a temporary stringer from the stem to the transom at the line defined by the top of the garboard plank. I beveled the bottom to keep that batten curve line intact. I used a short piece of wood against the bevel and the stringer as a guide to how much bevel to make. The moulds didn't fit perfectly but as long as the amidships frame fit perfectly that was ok.

As a side note, in my case I discovered that I had lofted the bottom wrong when I tried to fit it for the first time. The stern end was one inch off the centerline. I was just able to get a second bottom out of the remaining 1/2" plywood.

Hope this helps and we'd sure like to see pictures.

Will.

[Jeff Benagh]

I noticed this on mine too. Since the center frame was perfect, I thought that had been careless with the molds.

It kind of continued a little through the rest of the planks but it did get better. The upper edge of each plank was always right on so I assumed this was the intent. It seems that you would almost want to design the molds this way as it can get the boat shape right but an error in the other direction would make a gap in the planks.

I may have some pictures with just the bottom on. I can only find later pictures right now which don't clearly show what you mention. If I find the other ones I can post them.

Good luck with the boat!

[Clinton B Chase]

TX guys...I think that is the right call to go with the midship frame points as the most important...I'll see if I can get a fair line with a batten through the new points but my bet is that some of the points will still be wide and that that was the intention.

I'll have to take some pics...I am not a great documenter but will shoot the the set up before I plank.

Cheers,
Clint

[Clinton B Chase]

Another Question: Did folks find that the garboard planks did not lie flush on station 1/2? It is dead on accurate to the lofting and checked out ok with a batten but I think due to the twist of the garboard did not lie on the station. I decided to just shim the mold to the plank rather than tack the plank to the mold (that caused a flat spot). What were other's experiences?

Cheers,
Clint

[Jeff Benagh]

I had exactly the same experience. There is not much bearing area at that station so I ignored it. The garboard seemed like it could only make contact the 1/2 station mold for half the width of the plank anyway since the sweep of the sheer falls way below the mold there (upside down).

I never found the photos I mentioned earlier. I did find two photos that illustrate this though.

It sounds like you are making rapid progress.

[Jeff Benagh]

Clinton,

<not sure about etiquitte here but...> check your private messages...

Jeff

[Clinton B Chase]

Question: Any tricky ideas on how to attach a very thin rub strip to my sheerstrake. It is a half round that is only about 1/4
thick x 1/2" wide. I'd like it to be finished bright.

Update:

http://img2.freeimagehosting.net/uploads/th.01ffe1d57a.jpg (http://img2.freeimagehosting.net/image.php?01ffe1d57a.jpg)

http://img2.freeimagehosting.net/uploads/th.8542726fc8.jpg (http://img2.freeimagehosting.net/image.php?8542726fc8.jpg)

Cheers,
Clint
PS That IS Steven B in background.

[Rick Starr]

I've always stuck mine on with 5200, held in place temporarily with small brads as necessary. I did this first time because I wanted it painted dark, and around here dark things get well up above epoxy-softening temperature. It worked well.

Good luck,

Rick