Un-stayed junk masts

Hallberg-Rassy

Active member
Joined
29 Oct 2020
Messages
246
Visit site
An unstayed mast is designed to resist bending, a cantilever as Little Sister pointed out.
I knew a guy whose boat came with a junk rig. He changed it back to a bermuda. He said the mast did tend to whiplash, the designer saying that this was supposed to be the way it absorbed wind shocks. I was surprised how slim it was, from memory about 150mm diameter in Alloy for a 25' boat. Needlespar made them.

I know nothing about them, but you do see a lot of unstayed trees and lamp posts, so I guess they are safe beyond a point most people consider sailing in.

I read up about Asian boats. Traditionally, there seemed to be a huge variety in rig designs but I can't say I remembered seeing anyone using them any more. One tactic was to have folding masts that they dropped to sit out storms with, so I guess they must have had some kind of stays to pull them back up with.
 

Bajansailor

Well-known member
Joined
27 Dec 2004
Messages
6,446
Location
Marine Surveyor in Barbados
Visit site
The Skye wing sail could perhaps be likened to a modern version of a junk rig?
Skye Wing - description

Skye wing sail.jpg

Similarly the Gallant rig which was first developed in the 1980's -
Home

http://www.voiles-alternatives.com/documents/ailes_souples/gallant/gallant_sailing_word_1991.pdf

Gallant Aphrodite.jpg

Here is an excellent article on the design of free standing masts, by Eric Sponberg (who is now sailing around the world, currently in Australia, on his 32' yacht which he designed himself - and she has a free standing rig).
https://www.ericwsponberg.com/free-standing-mast-designs/

I keep tabs on their adventures via his wife's excellent blog -
The Old Woman and the Sea – Arliss Ryan
 

LittleSister

Well-known member
Joined
12 Nov 2007
Messages
17,545
Location
Me Norfolk/Suffolk border - Boat Deben & Southwold
Visit site
I've sailed many miles in a junk-rigged schooner. It wasn't close winded, but I don't think you'll find anyone who claims junk rig is*.

It had some other drawbacks, too - e.g. weight; & miles of rope in the cockpit - but was excellent cruising rig - great downwind; reefing was easier than any Bermudan or (European style) gaffer (just ease the halyard); no sail flogging; no worries about gybes; running by the lee no problem at all (there's no shrouds, so boom can go right forward if need be); everything very low tension; and low tech so could be repaired anywhere without specialist parts, tools, skills or materials; etc..

*You can get a junk rig more close winded by making it more complicated - cambered battens, sailcloths both sides of mast etc., but to my mind each of these loses some of the simplicity and ease of use of the basic junk rig.

Clearly doesn't attract or suit most people, but vive la difference!
 

Laminar Flow

Well-known member
Joined
14 Jan 2020
Messages
1,843
Location
West Coast
Visit site
The Skye wing sail could perhaps be likened to a modern version of a junk rig?
Skye Wing - description

View attachment 101841

Similarly the Gallant rig which was first developed in the 1980's -
Home

http://www.voiles-alternatives.com/documents/ailes_souples/gallant/gallant_sailing_word_1991.pdf

View attachment 101842

Here is an excellent article on the design of free standing masts, by Eric Sponberg (who is now sailing around the world, currently in Australia, on his 32' yacht which he designed himself - and she has a free standing rig).
https://www.ericwsponberg.com/free-standing-mast-designs/

I keep tabs on their adventures via his wife's excellent blog -
The Old Woman and the Sea – Arliss Ryan
Thank you for that, excellent post.
 

scruff

Well-known member
Joined
2 Mar 2007
Messages
1,171
Location
Over here
Visit site
I've sailed many miles in a junk-rigged schooner. It wasn't close winded, but I don't think you'll find anyone who claims junk rig is*.

It had some other drawbacks, too - e.g. weight; & miles of rope in the cockpit - but was excellent cruising rig - great downwind; reefing was easier than any Bermudan or (European style) gaffer (just ease the halyard); no sail flogging; no worries about gybes; running by the lee no problem at all (there's no shrouds, so boom can go right forward if need be); everything very low tension; and low tech so could be repaired anywhere without specialist parts, tools, skills or materials; etc..

*You can get a junk rig more close winded by making it more complicated - cambered battens, sailcloths both sides of mast etc., but to my mind each of these loses some of the simplicity and ease of use of the basic junk rig.

Clearly doesn't attract or suit most people, but vive la difference!


I do have a hankering to try a junk. Do all sizes of rigg have similar attributes? By that I mean I might fancy* one for my next "proper" boat at circa 40ft, but would prefer to have a cheap wee 18-20fter with a junk to trial for a season or two before dropping serious cash on an experimental (to me) rig.

*Annie hill's books may have a lot to answer for!
 

Black Sheep

Well-known member
Joined
13 Nov 2005
Messages
1,958
Location
East coast, UK
Visit site
I do have a hankering to try a junk. Do all sizes of rigg have similar attributes? By that I mean I might fancy* one for my next "proper" boat at circa 40ft, but would prefer to have a cheap wee 18-20fter with a junk to trial for a season or two before dropping serious cash on an experimental (to me) rig.

*Annie hill's books may have a lot to answer for!
My first recommendation to join the Junk Rig Association - I think £7 a year.

A cheap wee 18-20 footer will be single masted. A 40 footer is pushing it for a single mast. One of the limitations is that because a junk sail is fully battened, and the battens need to be reasonably substantial to hold the shape, there's a maximum sail size that one person can reasonably raise. Normally quoted at 500-600 square feet but I don't know the working behind that figure. It will assume a multipart halyard, but may not allow for lightweight carbon battens. So you may just about manage a single mast, but more likely you'll be looking at two-masted.

The other big thing to watch is, if you pick up an 18-20 footer, to make sure that it has modern cambered sails. If it has flat cut sails (as they all did until 20 or so years ago) it will live up to the poor reputation with which some people still regard Junks.

As long as you're looking at cambered for both the tiddler and the 40 footer, the only major difference will be the number of masts. If you can manage just one, then no real difference apart from scale (especially managing the halyard). If you end up with two masts (ketch or schooner) it will be easier to balance the boat, but it's possible the sheeting arrangements might be more complex. One of the nice things about a junk is that the main has a single sheet (like a bermudian main, but unlike a genoa) so no sheet management when you tack. With two masts, you may be able to manage this (depending on the geometry) but you may need the forward sail to be double-sheeted (one sheet each side, more like a genoa). This would mean a little more work every time you tack... but not as much as tacking a genoa.

I hope that helps. Someone will be along in a mo to tell me what I've missed
 

Blueboatman

Well-known member
Joined
10 Jul 2005
Messages
13,717
Visit site
I would only add:
It is always fun to try a different type of sailing?

The combination of a simple una-rig and shallow draft can be brilliant for pottering up rivers right to the headwaters .. .
Real Swallows and Amazons stuff if that means anything .
And is brilliant for ‘’ touch and go‘’ sailing . Heading up the narrowest and twistiest of rivers tacking back and forth you just push the tiller over as soon as the leeward keel starts ‘sounding’, touching the mud..and sail off on the other tack without adjusting anything.
And with a full battened sail, one can make very ...s l o w t a c k s ...letting the flood tide carry the boat usefully along whilst head to wind.. all impeccably mannered and free of flogging sails..
They also don’t heel much either, which is.... nice?

Dinghy sailing really, with dinghy simplicity, dinghy running costs and dinghy fun ‘n smiles.

Gary Hoyt came up with a natty spinnaker and pole set up mounted on the pullpit in addition to the una-rig mainsail. I expect the OP is aware of these offerings too of course..
I think if I were ( now) looking at a small junk rig “ try one out” purchase, one might take a look at the Hoyt Freedom 25 too?


Coastal sailing wise, tides are your greatest ( perhaps , sometimes your only) friend for assisting flat panel junkrig to make satisfactory windward progress , particularly into any sort of a really lumpy headsea. That has been my experience .

Can you tell I remain a big fan??
 
Last edited:

Hallberg-Rassy

Active member
Joined
29 Oct 2020
Messages
246
Visit site
Those two sails are an almost perfect "Spitfire" wing. How does it sail? I wonder why, however. I suppose reducing the area at the top of the mast reduces the leverage forces where the mast is the weakest, but wouldn't it be the top where you wanted the most area for catching the lightest winds?

I've looked into this subject a little, as I like the simplicity angle. The practical problem appears to be finding an actual mast. I know some people have managed to use lamp posts, but it seems the suppliers really aren't interested in dealing with one off requests from sailors.

I also read that the carbon fibre masts used by the Freedoms use shatter with a great deal of force when they finally break, unlike wooden ones that splinter. But that alloy ones can just fold.

It strikes me a little extra weight would have a dampening effect on a boat's rolling and not be so bad.

 

Black Sheep

Well-known member
Joined
13 Nov 2005
Messages
1,958
Location
East coast, UK
Visit site
Those two sails are an almost perfect "Spitfire" wing. How does it sail? I wonder why, however. I suppose reducing the area at the top of the mast reduces the leverage forces where the mast is the weakest, but wouldn't it be the top where you wanted the most area for catching the lightest winds?

I've looked into this subject a little, as I like the simplicity angle. The practical problem appears to be finding an actual mast. I know some people have managed to use lamp posts, but it seems the suppliers really aren't interested in dealing with one off requests from sailors.

I also read that the carbon fibre masts used by the Freedoms use shatter with a great deal of force when they finally break, unlike wooden ones that splinter. But that alloy ones can just fold.

It strikes me a little extra weight would have a dampening effect on a boat's rolling and not be so bad.
I can't speak for the Gallant rig, but although you want lots of canvas high up in light winds (especially for a river boat, hence Thames Barge topsails), in heavy winds you definitely don't! With a normal junk, you reef the sail down such that the top panel or two constitute your storm canvas. You'll normally want those not too big.

You're right that sorting out a mast is one of the issues in converting to junk (another is fitting it in the boat... on a sloop it will be forward of the bermudian mast and normally in a very inconvenient position!). Don't be too disheartened by all the tales of how every material known to man is unsuitable and dangerous! Depending on your vessel you've got...
* lamp posts (don't tell them it's for a mast)
* straight alloy tube
* steel tube, straight or tapered. Only for the larger boat, because of weight, but cheap and easy to work
* solid wood. Again for the larger boat. Something very satisfying about a grown wood spar
* hollow wood. Birds foot and other constructions. Cheap materials, more or less complex to make depending on design
* carbon fibre. The Rolls Royce of masts with a price to match. The raw materials are hugely pricey, but I don't know of any amateurs building their own carbon masts. But strong and light
* GRP.

And that's before you get to hybrid masts. A lower tube of alloy with a solid wood tapered topmast is a popular design. Or two alloy tubes of different diameter with various ways of bridging the gap (I have a mast where the narrower topmast is sheathed in wood tapering out to the diameter of the lower mast)

There's a lot of scope for imaginative design, if that takes your fancy. Or buy something already converted and in commission.

The simplicity of sailing (especially single handed) is what does it for me.
 

DownWest

Well-known member
Joined
25 Dec 2007
Messages
12,860
Location
S.W. France
Visit site
On wooden masts..all the spars on my little boat are birdsmouth. I can get nice Douglas Fir in 6mt lengths. So, based on experience, I expect I could build a 11 mtr mast in around three days, not counting glue setting time, to a stage ready for sanding and finishing.

Over on the Duckworks site, there are links to DIY carbon masts with kits supplied. Not big ones, but might be OK for a 20ft fun boat. The kits didn't look that expensive.
 

Buck Turgidson

Well-known member
Joined
10 Apr 2012
Messages
3,125
Location
Zürich
Visit site
Those elliptical wing sails look like a good idea. We all love the spitfire and the book quotes about elliptical plan forms giving optimum lift distribution therefore minimising induced drag. however, it is not correct for a vertical wing because of the wind gradient close to the ground.
there is probably 20% difference in wind speed from the top to the bottom of that sail making it very tip loaded.

A perfect example of only applying part of the equation.
 
Last edited:

Hallberg-Rassy

Active member
Joined
29 Oct 2020
Messages
246
Visit site
What does that mean, and what might be the optimum shape?

Black sheep, do you know a lamp post supplier who sells one offs?

I did find a perfectly shaped tapered lamp post for a 20-something boat that "fell off the back of a lorry". Or rather, in this case, had probably been hit by a lorry and was destined for scrap. Unfortunately it was made out of steel and fairly heavy unless you had an old wooden or steel boat. No such luck with alloy.

Recently, I had a chance to look at a traditional Thames barge. I thought they were gaffs but actually you don't pull their booms/sails up, rather let them drop down.
 

Black Sheep

Well-known member
Joined
13 Nov 2005
Messages
1,958
Location
East coast, UK
Visit site
I'm afraid I've never actually chased lamp posts (or lighting columns as they prefer to call them) enough to investigate. But I think I heard that Marwood Electrical would www.marwoodelectrical.co.uk. Unfortunately they've taken all their products off their website! But I did hear anecdotally on the JRA forums that if you tell any supplier you want to use it as a mast, they get very worried about liability and clam up.

Yes - the Thames Barge is a Spritsail rig. Another rig I'd love to have a play with! Reefing the main is a matter of brailling it up. They often use just their topsails for close quarters manoeuvering. They can make sailing the Thames Estuary a delight!
 

JumbleDuck

Well-known member
Joined
8 Aug 2013
Messages
24,167
Location
SW Scotland
Visit site
I also read that the carbon fibre masts used by the Freedoms use shatter with a great deal of force when they finally break, unlike wooden ones that splinter.
Although very strong, carbon fibre is also very brittle so yes, when it breaks it tends to shatter into lots of sharp-edged shards. For this reason glider cockpits made of cfrp also have glass or kevlar layers - carbon on its own is horrible for crashworthiness.
 
Top