Norwegian built Kombi Jolle dinghy with lug sail

Hi Folks,
I have recently acquired a 1960s (Norwegian)Kombi Jolle Lug rigged dinghy. The boat has a rigging design I have not seen before. The lower boom is not lashed alongside the mast but is inserted through the mast with a couple of inches protruding at the front. The foot of the sail obviously cannot extend in front of the mast. I am assuming that the mast must rotate under pressure from a filled sail. I would be grateful if anyone is able to assist me with my dilemma. I am attaching photographs showing how the boom fits through the mast.

 

For the sail to work as intended, the mast must be able rotate easily. There are many boats that use a rotating mast.

The pictures suggest that you have the sail strung up much too tightly. Adjust the ends in such a way that the wrinkles in the sail go away. Also ease up a bit on the line that lashes the foot of the sail to the boom. There are more desirable ways to lash the sails to the spars than the spiral winding that I see in the picture.

I like the boat. It is a classic. Do some work on the sail, that is going to be a fun little boat.

 

Hi Messabout,
Thanks for your response. I have absolutely no knowledge of how this dinghy should be rigged, so your advice is welcome. I have never used a lug sail. I will experiment with the set up. As shown is how the sail was attached when I got the boat, less than a week ago. You mention that there is a more desirable way to lash the sail to the spars. Arer you able to point me to a source where I can find out how to do it properly? I would be grateful for that and any other knowledge that you can pass on.

I'm glad you think she's a classic. That was my thought when I first saw her.

Many thanks.


Grant

 

I had a rotating spar on my vattern snipa, which was sprit rigged. The mast foot will be either be in a small "cup" or will have a pin that mounts in a hole. I did away with the sprit after a while and went to a balanced lug sail which improved ability no end. Your boat should perform well with that rig. Those wrinkles will most likely disappear when the sail is full of wind. It is a very adjustable sail.

 

Hi Grant, that's nice looking woodwork on that boat, keep any varnish chips and scrapes sealed and it will remain beautiful. Messabout is right, loose the spiral lashing on the boom, and just have the sail attached to the boom at the tack, (front eyelet by the mast) and at the clew (rear most eylet on the sail foot), so the sail foot can have some curvature, called a 'loose foot', giving it a more aerodynamic shape. Have a basic out haul on the boom to loosen or tighten the clew rearward along the boom to adjust foot shape, and another loop of cordage through the clew eye and around the boom to keep the clew from lifting up too high when the sail is slack and baggy. Slack baggy sail foot in light winds, and pulled tight in strong winds. Keep the spiral lashing on the yard, and make that fairly tight. You may benefit from a simple loose parrel holding the yard near the mast, so it doesn't swing out when raising and lowering the yard; just a length of cordage half around the mast above the yard, then both ends over the yard, back under between yard and sail, and then loosely tied around the mast below the yard, tied with a reef knot. Loose so the yard slips up and down the mast easily. With your boom setup, the sail's up haul needs to be very tight to give you a straight luff (front of sail), pulling the sail tight up from the boom tongue notched in the mast end. Make sure the mast / boom rotates freely, without binding or boring a hole into the boat's bottom; some lard or wax on the bearing surfaces may help. Make sure the mast and sail can't be lifted up out of the hole if caught by a swift gust.
As skaraborgcraft mentions, the sail wrinkles will be less obvious when filled with some wind.
See my lug sail dinghy on here in a post called" 'Jack Holt Heron re-imagined Part 5', I think it's called.
There are some lug sail tips at : LIST of WOODEN BOAT PLANS - By Michael Storer https://www.storerboatplans.com . Wear a buoyancy vest and have fun.

 

Hi Skaraborgcraft
Many thanks for your help. I will do my best to follow your advice. I am a RYA power boat instructor but have little experience in sailing. I also have a gunter-rigged clinker-built Tideway but she is too heavy for me to manhandle into the water on my own. So my new boat will be my focus. The mast foot sits in a small cup and the mast rotates easily in it. I will try to adjust the sail as suggested. I will use the spar as it is at the moment, i.e. set into the mast and see how that goes.

Best wishes,

Grant

 

Hi Seasquirt,
Many thanks for your very detailed response. My background is with Motor boats and my sailing experience is almost nil so I have a lot to learn. You have given me a lot to digest but I will persevere. I will certainly wear a buoyancy aid, my club insist on that being done. I have already revarnished any scuffs and wear and Peanut is looking much better now. Your suggestion to grease the cup is one I had wondered about, so thanks for that. Do you advise that I continue to use the spar inset into the mast? The rest of your advice will take some time to get to grips with. A the moment I'm just trying to take it all in. It certainly looks as though I made the right choice when I chose this forum to join. The responses have been overwhelming. I'm still hoping to hear from another Komi Jolle owner. New images are of the

Best wishes,

Grant

 

To be fair, your sail looks old and stretched anyhoo. However with square sails you do have 4 edges you can adjust by various means. One of the better info sites on sailing with lug is from Mik Storer, which you might find some help/interest in.

20 ways to boost Lug rig and lug sail performance! Rigging and Tuning. - Storer Boat Plans in Wood and Plywood
.

 

Yes use the boom located in the mast as designed. If you try it as a balanced lug, with the boom alongside the mast and forward, with another parrel on the boom and mast, then the back end of the boom will swing down and be almost in your lap, due to the sail's shape. You could experiment with your existing sail as a balanced lug sail if you put extra eyelets in the luff and leech for reefing purposes. A sail maker can do that for you easily. There are suppliers of balanced lug sails you could buy from, selling generic shapes and sizes which will fit your mast size, and sail's area, but see how it goes as it is first. Don't do too much modifying until you have learned how it sails as standard, it might already be 'just right' for the hull shape. Be aware that the boom's slot in the mast is a potential weak point, and the mast could snap there if hit with a strong wind, or rough handling. Remember to lift up your dagger board before beaching it, or you may stop suddenly, and even snap the board or damage the centre case. The rudder will be pushed up by the ground in shallow water, and not be such an issue. Good luck with it, and get back with any other questions. And tell us how it sails. I'm sure another sailor will be glad to teach you how to operate it all easily, - 'show you the ropes'.

 

All points noted, thank you. I'll let you know how I get on.

Grant

 

Another boat that has Scandinavian origins an originally had a boom that passed through the mast is the OK.It might not be too relevant in this context but it might be worth seeking out a few pictures of the older boats to illustrate how they were intended to work.

 

Hi Thanks,
I'll do a search. It may be helpful.
Many thanks,
Grant

 

The information in my handy little Dinghy Year Book of 1962 shows that the Kombi originally had;

1- a rather shallow fixed rudder; yours looks better IMHO.

2- loops to hold the sail to the boom and the yard. The plan I has shows a series of individual loops rather than the lacing. A sail that is secured to the boom can have deep curvature if the sailmaker has chosen the curve in the relevant cloth seams and in the foot of the sail.

3- the boom going through a slot as in your boat and in the original versions of the Finn and OK dinghies. Finns (and I assume OKs) used to have a wedge that went inside the mast slot to hold the boom down.

4 - short battens in the plan, but long battens as in your boat in the photograph. Long battens were very unusual in European boats at the time and when I first saw your pics I assumed someone had designed a new sail. So apart from the rudder your boat looks original, which is nice.

As Seasquirt says, lug sails require lots of downhaul tension to keep the luff tight. On my 7'6" lugger I am going to rig up a 4:1 using roller-bearing blocks and non-stretch line because otherwise that can develop a nasty crease from the front of the boom to the back of the yard.

The creases in the bottom pic look to me to be mainly caused by the battens being too short; they should be a squeeze to get in. The two full battens would normally have light lines that go around the back of the batten and allow you to tighten the batten to take out the creases.