Tradition Junk Frame Question

Hi,

I am planning on starting to mill lumber for a 28' junk.

I have been researching how the japanese frame junks and it has been very interesting.

I am looking at the plan Jiantou at

http://www.thomashoppe.net/Drawings_of_Chinese_Junks

On the 5th page there is a drawing of the main frame. Am I right in thinking that the frames are put together more like a timber frame. Like how you would build the stem?

I have never seen a boat built without either bent frames or double-sawn.

Also do you think all the measurements are in centemeters? Thanks ahead for any help you guys can give. I don't have any junks i can go look at up here in Tenakee Springs, Alaska and I really could use some help from somebody with some experience with traditional japanese junk boat carpentry.

thanks,
Sterling Chew

 

Sterling,
Predominantly the dimensions are in mm.
Use the context of the specification to determine whether they are mm or meters.
The frames appear to be sawn, and assembled in 3 or 5 futtocks with minimal overlap where they're somehow fastened (western standard would be through bolts).
The stem could be easily bent, or less likely laminated.

 

thanks

thank you,

One other question I have is about frame spacings?

There are ten lines drawn for the shape. So with sawn frames would that be 10 frames?

 

The scale is given on these drawings. You should print them at a large scale so you can use dividers to take the distance off of the plans and lay it on the scale provided. I did this on my computer screen and see that 3 of the frames are spaced approximately 650 mm (center to center), but it's not consistent. A couple have closer spacing. No idea why this is, but it's not abnormal. Sometimes function dictates. Note also that some of the futtocks overlap on the forward face and some on the aft face. Here also I can't tell exactly why. There are many reasons it could be (maximizing space for built in lockers, etc.).

 

This is Karsten Petersen's site that has 2 construction photos on page 2 that might help. You can e mail him at...
karstenp@post7.tele.dk
and he might be able to tell you some more detail.

http://global-mariner.com/index111ChineseJunks.html

 

Thanks guys. There are sure some cool pictures of junks on that site.

Another thing I am confused about is if they specify a centerboard or leeboards on those plans? it looks to me that the boat doesn't really have any kind of keel.

Do you know what the usual Junk's have??

So when out get to sawing out futtock's do you think I can cut those out of a timber? or am I going to have to get natural crooks?

They specify lumber size's for them and in the frame drawing they seem to be a dimensional board with the curve cut on the outside and the inside left straight?

I can probably find a fair number of curved spruce tree stems. And a few cedar tree's I have been keeping my eye on that grew in a real nice curve. But to get enough dry to build a boat like this I sure i would have to find and cut a lot of them.

What I would like to do would be to be able to frame the majority of this boat with lumber cut on my mill and then use the crooks i can find where they best meet the curve of the boat.
thanks,

 

Hi Swirlyboy, how is it going with the junk?

I am also looking at building a junk but having no previous experience I need something more than the diagrams on that site (thanks for posting it though) I am looking at http://www.jonquedeplaisance.net/index2.html for some plans, they are not cheap but there are enough of them around so I know it should float if I do it right.

After a google I found that a large rudder is used as a keel but on the old versions it would take the strenght of a few people to move the rudder it was so big, I also read that some have daggerboards or leeboards. Google and Wiki have lots of historical information on Junks and this forum can fill in the expert knowledge for the details.

Good Luck

 

The Karsten Peterson photos and texts are fascinating.

It would be interesting to know why you want to build a Junk rather than a more conventional design? Not challenging you here, just curious.

 

Apologies to those who have read my previous posts.

Messabout :

Back in the early 80s I had a calendar, I think it was a freebie because every picture had the phrase 'Anytime, Anyplace, Anywhere' on it. Apparently one of the places you could enjoy a Martini was in Hong Kong Harbour as they had a picture of the harbour with a very majestic looking orange sailed junk in the foreground.

Living in England my only experience of being on the water was the ferry from Dover to Calais, which didn't exactly instill a love of the ocean for me. I don't eat fish, I don't swim so pretty much 70% of the world is dead to me. The junk is pretty much the only thing about the ocean that looked worthwhile and I guess I was an early teen and very impressionable. It must have imprinted on my psyche.

However having come to Australia and been invited onto a few boats I can see that maybe it isn't all bad. I am joining a crew each weekend for racing and a bit of experience.

I am not competitive and having the boat on a 15% lean for most of the journey seems a little uncomfortable. They also seem to have a hundred different coloured ropes and ALL of them are important.

I am interested in the look of a junk, no other boats inspire me enough to want to own one. I am not interested in speed, an upright ride, is a fair compensation for less performance to windward. Sails that do not perform to the current possibilities is a fair compromise for losing most of the ropes, pulleys and cranks. The wood bit I could probably be talked out of, especially as it seems hard to get.

I have been given plenty of advice not to get a wooden boat and certainly not to get a junk.....but how many people pay attention to free advice?

I am sure that I will spend a few years struggling to keep it clean and maintain it... a few years struggling with poor performance trying different sails to find if there really is a modern cambered solution to a centuries old problem. And after that I will probably concede that all the sailors who have been sailing for years and have plenty of experience were right. It will take about 15 years for me to build the junk, just in time to retire, I should be able to sail by then. I will sail around until I run out of money or get bored and then find another junk fanatic to sell it to and back inland.

I can't speak for anyone else though, they are probably just mad.

Mark