Currach building

oscarthefuzz · Post by **oscarthefuzz** » Sun Jul 01, 2012 6:22 pm

First time posting any of my projects so not sure it's acceptable to just post a link but let me know...
First time building a boat, think there's a few people on here who are interested in that kind of thing

http://naomhog.blogspot.ca

lightnin · Post by **lightnin** » Tue Jul 03, 2012 1:56 am

Nice work. Both of my grandfathers built boats.

JPG · Post by **JPG** » Tue Jul 03, 2012 11:44 am

oscarthefuzz wrote:First time posting any of my projects so not sure it's acceptable to just post a link but let me know...
First time building a boat, think there's a few people on here who are interested in that kind of thing

http://naomhog.blogspot.ca

We like links where we might learn something.

PM Shipwright for advice re 'pointy end' splitting.

Or if ya be lucky, he might respond to this thread on his own so we all learn!

shipwright · Post by **shipwright** » Tue Jul 03, 2012 1:03 pm

Yes I'm still here. I had a look at the blog and if I were being asked "how it's done" or why did the pieces split, this would be my answer.

Simply put, you bent the piece in the wrong plane. The normal way of forming this part of any boat is to start with a "sheer clamp" which is a bent piece like the one you show but it is never bent the way you bent it. What you did is what boat builders call edge-setting or trying to bend a piece on the plane of its greater dimension, its width rather than its thickness. Sheer clamps are always bent on their thickness with the width being the vertical side. On larger boats (or if you want a wide flat gunwale on a small boat) there is another piece added on the top of the sheer clamp. It is called the shelf or beam shelf indicating its use in larger boats. On small boats like yours it would be the rail cap.This piece is always sawn to shape, never bent.

Secondly, breasthooks are usually attached with through bolts or some method more substantial than glue as the mating side of the breasthook itself is mostly end grain and there may be substantial forces at work against the joint.

I hope this of some help. If you want a good resource on all facets of wood boatbuilding there is none better than Howard I. Chapelle's "Boatbuilding" first published in 1941.

Paul M

JPG · Post by **JPG** » Tue Jul 03, 2012 1:18 pm

Paul:

I am glad you took the time to help him.

There was no doubt in my mind that you would understand why he was having the problem and how to avoid it!

When one has the expertise(as you have) and a novice cries for help(as he did) a personal 'invitation' to help is not necessary, but volunteering it is I am sure much appreciated.

Again the craftsman responds!!!!

Kudos!

And thank you for the open response so we all learn.

foxtrapper · Post by **foxtrapper** » Tue Jul 03, 2012 1:37 pm

Something else to consider with that piece, is that normally it is not a single board, but a laminate. The pieces are bent, then joined. On small boats, the common example of this is canoes and their rails. A thin inner piece, spacer blocks, and another thin outer piece.

Another thing is steam bending. I didn't see it mentioned on your blog, but this is a very important bit of board bending. You steam the piece to make it pliable, then bend it to shape and let it cool and set. With a steam box, you could flat bend a wide board. Still wouldn't be easy, but it becomes a lot more possible.

oscarthefuzz · Post by **oscarthefuzz** » Tue Jul 03, 2012 10:15 pm

@shipwright

Thanks for the input, what we are going to try next to fix it is along the lines of what you are suggesting with the cap rail, maybe more like a gusset? Kinda like a plate underneath the joint to hold it altogether, it's going to be set back a little bit and the stringers will run on to it and get nailed to it. On this type of boat the gunnels are always bent that way and never on edge, it's the same method that has been used for 200 years in their 'modern' incarnation so I am trying to keep it as true as possible to this type of boat.
Thanks for the suggestion on the book, was looking for a general boat-building book for future projects and have seen that suggested on forums so will see if I can pick up a copy.

@foxtrapper

There is actually quite a lot on steam bending in the blog. we have made some mistakes on it but we're learning every time we do it, thanks for looking everyone!

oscarthefuzz · Post by **oscarthefuzz** » Tue Jul 03, 2012 10:27 pm

@Shipwright

Just picked a 1941 copy of Chapelle Boatbuilding for only 23 bucks, thanks for the suggestion once again...