Conversion To Junk Rig
Conversion To Junk Rig
Your website has dispelled many of my prejudices regarding ferrocement construction, and I would now be prepared to consider buying a s/h yacht with such a hull. However I am a junk rig fanatic, and might need to convert to this rig, using unstayed mast(s). Are there any particular problems associated with ferrocement construction regarding relocation of the mast/ stresses at the partners, etc. ? BTW - useful site ! Regards
hi colin and thanks for the very quick response, the reason we mailed you is because we are planning to buy a fijian here in the uk the "westaway", and there seems to be some debate by us from different documents as to its length, it has also been rigged out as a 2 masted junk and we wondered what (if any) effect this would have to the design. it is a lovely boat but we have heard many times that a ferro boat needs to be "poured in one hit" and we can only think that that means you pour the cement over the frame all at once then shape out and smooth over. however from pictures of the build they are plastering the hull in the same way as you would a wall, trowel and board. once from the outside and again from the inside, please can you rest our minds at ease? we have atached a pic of her for you to see.
Hi, I have also today received another enquiry regarding 'junk rig', so I thought it appropriate to post Lee Hilliers question and picture and then answer both yours and Lee's together.
Hi Lee, There are two reasons why you should be very wary if considering purchasing this vessel. The 'Fijian', was not designed to be junk rigged. There are two factors that must be taken in to consideration a/ The balance of the rig. b/ The stress of the rig on the hull. Even though I do not have access to the sail plan of the Fijian in the picture, I am fairly certain that the rig as shown will not balance on that hull with her underwater shape. With regard to the the stress of the rig on the hull. Whatever material the hull and deck is made of, special considerations must be put in place to successfully transfer the loading to the hull. In this particular instance the forefoot is in my opinion unable to take the compression unless dramatic changes to the hull design have been undertaken. The design of both the deck and hull in way of the masts must also undergo major alterations. I voiced my opinions with regard to another Fijian similarly altered to junk rig two years ago, while I was inspecting her. She has since been lost whilst in the hands of a very experienced ocean sailer. The sad part about it is that there is nothing to be gained by using the junk rig, infact it's quite the reverse. The junk rig has but one advantage.....that the sails can be hand made out of small pieces of cloth (the only reason why the rig has lasted in the poorer areas of the world). Regards
dear colin, i have just read your mail in the forum about the stress loads on the hull of the Fijian from a junk rig, the decks of westaway are ferro also and were strengthened by a solid ring for the mast to fit into then metal spars leading away from the ring in all directions that are worked in with ferro, the boat was never converted but built from new as a junk rig, however she has not been sailed in heavy seas as yet so not proven. i have no idea as to what if any extra re-enforcement has been made to the steps as the builder/owner sadly died. my next question is from my surveyor as to the draft, she is about 7.2 ft and he told me this is a ft too deep, he also would like to know how much dry draft aft and forward there should be? the transom is dragging very close to the waterline and she looks low at the bow. maybe re-enforcement has made her slightly heavy? just to remind you her LOA is 47ft. ps she is out of the water until monday.
Hi Lee, this now comes back to one of my previous statements about the dangers of unqualified alterations. The more you tell me with regard to 'Westaway', the more horrified I become. Obviously there have been dramatic changes to the designed underwater shape of the hull, your surveyer is correct (and obviously concerned), in pointing out to you that her draught is1ft different than designed. With regard to extra re-inforcing causing her to be lower in the water, I would think that highly unlikely. Let's face it...on her size hull I would estimate off the top of my head that even 1 ton extra would still represent less than an inch increase in draught. On the 'Fijian', the waterline aft is at a point approx halfway between the bottom of the transom and the top of the rudder post. The very tip of the top of the rudder just shows. You say the boat has not been converted. You are right Lee....she is not a 'Hartley Fijian'. She has a different shape, rig, length and construction......the only point in common is that she is a ferroboat....and I can only wonder how that might have been modified from our plans! Looks to me like another ferroboat by an 'amateur expert' !!!!
For those considering a junk rig, there is a book titled "Practical Junk Rig" by HG (Blondie) Hasler and JK McLeod that ranges from technical engineering design to practical plans for rigging. It's as great a book on junk rigs as Colin Brookes is on ferrocement. It is being reprinted by Tiller, St. Michaels in Maryland USA and is available through them or Adlard Coles at about $75 US. One advantage with the junk rig is ease in sail handling for those of us getting beyond middle age. Blondie Hassler founded the first single-handed transatlantic race and came in second to Francis Chichester in that race. In Chichester's account of the race he often comments on being too tired to make sail changes while Hassler alters his with so little effort. Thanks for getting the forum going again Colin.
Ellis Bloomfield.... firstname.lastname@example.org
Hasler certainly gained some experience with his rig in the Trans Atlantic Race. But the crucial bit you left out Ellis my friend, was that Chichester was not only old enough to be Hasler's father.... but Hasler's boat was just a mere dinghy in size comparison to Chichester's. A 16 year old boy sailed the oceans for 5 years with ease in a boat similar to Hasler's with a Bermudan sloop rig.