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Rob Blackburn

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Rob Blackburn last won the day on November 28 2017

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About Rob Blackburn

  • Birthday 01/01/1

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    Lennox Head Australia

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  1. Yes, great weekend for sure. Weather was perfect and we came across about fifty, or more... Dugong out on the sand banks. Really amazing. Why did we add a mizzen, well basically I think the honest answer is in two parts. 1...I put the mainmast in the wrong spot I suspect. I think it should have been about 300mm further aft. This has corrected the very neutral helm, bordering on lee helm at times. and 2... Friends have a Bayraider 20 and I just loved the way they can drop the main, sail on jib and mizzen and put in water ballast and keep their hair on. So have put a pump in with some plumbing to fill the side storage tanks if needed (together or singly) and can take on 340 litres which makes a difference. The other third part to the answer is I am a bit of a tragic and love mucking around with it all. All good fun and if nobody sees the bills then it did not cost anything. Rob ps Drew, give us a hoy when you are up this way. Love to see the new improved version III.
  2. Thought you may be interested in seeing Allecat (vs 3.0 with new mizzen) on a boys weekend in Moreton Bay Australia. Great weather, great sailing and good company. https://photos.app.goo.gl/78CcxBKOXJenZORj1
  3. Thought you may be interested in seeing Allecat (vs 3.0 with new mizzen) on a boys weekend in Moreton Bay Australia. Great weather, great sailing and good company. https://photos.app.goo.gl/78CcxBKOXJenZORj1
  4. Well, sea trials have finally been had on the new arrangement and I am pleased to report it all worked a treat. The aft side lockers on our boat take exactly a hundred litres so started by filling them with a bilge pump dangled over the side with a hose attached. Immediately settled the boat. Then filled the forward lockers as well, another 65 litres per side. So all up 330litres on board. Perfect. Balanced nicely fore and aft and just was not bothered by the gusts coming around buildings etc on the river. The boat was so much more stable with just the wife and I aboard and did not heel much at all with the gusts. We did not have a lot of time so then did a few runs with only water in the windward side and that too worked a treat. I can't believe I have not tried this at some point in the past 14 years we have had the boat. All you really need is a bucket to fill it really. Was standing in the queue at the hardware store looking at the display of bags of cement. Each 20kg. So sixteen bags of cement on board was effectively the load, down low and out of sight. It is a worthy experiment. Rob
  5. The first day of our trip to Tasmania we had 2 Bayraiders on the raid arrive. (Tawe Nunnugah 2017... google it https://goo.gl/photos/mQsctBKu1TNzgcma6 ) (We also had a CS 17 along and they were great company. (Wyvern)) Here is a set of photos I sent to the owner of one of them that I took of them sailing in a fairly strong breeze. https://goo.gl/photos/eyLCiGTTmDSBJqr86 The video in this set is instructive. They put the water in and if you look at the video the boat just sits in the water. We would have been on our ear I suspect. Mind you I have come to the conclusion we have made a fundamental error when we put the sloop rig on the boat. We should not have put a fully battened main on. I think the BR yawl would have been better (bigger main, small self tacking jib, mizzen). With a soft main, so it is easier to feather etc in stronger winds. (we are approaching 60 years) I loved our cat ketch but for down in places like Tasmania with very variable and gusty cold wind it was just a big ask for the two of us to be reefing it the way we had it setup. We did not put tracks on the masts and paid the price. It was a pity I did not understand it all better at the time. The day after that was taken we sailed up the coast and the wind came out of the NW at 35 knots after lunch. We had 2 boats swamped but the Bayraiders dropped their mains and sailed up on jib and mizzen with the water in without a care in the world. So which rig is best, that is an impossible answer but I guess all I saw was the effect of the water going in, the boat stiffening up and the crew looking cheerful. (The hull really does not know what sort of rig is on top IMHO, it is the sum of the forces that count.) We put the motor on in the end that day, served out rum and raisin chocolate and glasses of Liqueur Muscat. So it was still a fun day. Won't forget it for a while.
  6. Yes Graham, I'm still extant as they say. The boat is going fine and bang for buck I have never had such a good return over the years. It has been a great asset to the family and has been a 'passport' to other things/people/places that would have been denied to us with a smaller one or a bigger one. So very happy. Still think it is a bit wet though... lol. I think the bit you have pointed out about the moving water around is really what I have in mind if this all comes together. The jabsco wake boat pump is reversible so I figure a set of 3 taps to direct the flow, a battery, solar panel and regulator which I have will be about all it needs. http://d.pr/i/sgg6 It was just so apparent to us the difference 300kg made some days on our friends boat. If you have the 3 separate blocks of water you could run with bow and windward side on a tack. Open the remaining tap for the empty tank, run the pump and fill the leeward one when you are approaching the tack, then tack, then pump out the new leeward tank. 100 litres will only take a couple of mins to shift too with the pump. So you are not vulnerable to having weight on the wrong side. Same with downwind, don't fill the bow one if it is boisterous. Anyway will see how this all pans out. Rob
  7. Thanks for that. It is all very confusing to a non naval architect. I guess the proof will be to get the boat back in the water and simply try it. The only cost will be the plastic bags for the wet sand. I am proposing an R and D budget here of about $20. I get what you are saying about the freeboard but when I watch the Bayraider in action, the key thing is that it seems to sit about 1 inch deeper in the water and stiffens up. So a gust won't put it on it's ear as much. If a capsize is looking imminent, then the freeboard is definitely an issue. I guess the other question is really, would the CS 20 be an easier boat to live with for a middle aged couple in gusty conditions if it had 300kg of ballast aboard. I suspect the answer will be yes. The boat won't know if the resulting mass increase is from water, boxes of wine, lead, spent uranium etc. I get the feeling that 300kg of lead in two ingots bolted to the sides of the centreboard case would alter the boat's response quite a bit so shall see. We had 12 people aboard to ferry them to boats one morning (see attached) and the boat was anchored in the water. That would be about a 1,000kg with outboard and jumpers and clothes etc that day. It floated lower of course but not diabolically. Anyway. Thanks for the reply, will report back after sea trials. R
  8. Evening All, I have a CS 20 and recently was sailing in company with a Bayraider 20 in Tasmania in gusty and windy conditions. What really struck me was when the going got tougher ie over 20knots with gusts, my friends filled their tanks with 300 litres of water and sat back to watch us carry on reefing etc as they sailed away victorious. We soon lost sight of them as the wind got stronger. The wife onboard was calmly knitting a woollie hat just to rub it in. Has anyone had a go at retrofitting water ballast to one of the Core Sounds? ie version one, (the classic original flavour). I have looked at our boat and can fit a hundred litres in each aft side locker and another 100 under the foredeck in front of the centreboard on the cockpit floor. I was thinking in wake boat ballast bags, nicely plumbed in and pretty much hidden. Jabsco wakeboat reversible pump to do the work. My distant university physics lectures suggest to me that the combined centre of mass of such an arrangement would be 2/3 of the way along the axis of the boat about 100mm off the floor of the keel. ie 100kg fore and 200kg aft. Pretty much perfect. So would it work? Reading on the Swallow Boats site it seems to me that Core Sound, having a hard chine out wide would be a prime candidate? What is the thinking here or have I missed an obvious point? It is just that at 56 I am trying to find a way to extend the comfortable use of our boat for the pair of us. We are not 25 and bulletproof anymore. My next plan is to simply try it with a 100kg of wet sand in the front on the floor in bags and fill both aft lockers with a bucket but I wont be able to for about 5 weeks. Rob Have attached a pdf on the topic. (And a shot of our daughter at the helm down at the bottom of Tasmania in Feb.)The Physics of Water Ballast - Swallow Yachts Association.pdf
  9. Hi Rob I see you went with the sloop rig. I must say with stays, topping lifts and lazy jacks integral with the stacking sail bag, a zip luff jib and full length battens I'm sure I could beat you in the race from stopping the car to sailing off the ramp. I only have 3 extra lines to clip on with snap hooks...the topping lift, the reefing line at the clew, and the reefing downhaul at the tack...compared to a standard CS17 with tracks. Everything else is permanently rigged. Certainly though a roller reefing jib is a terrific way to reduce sail area quickly. You are probably a bit quicker to windward which is always nice. Cheers Peter HK I guess when I say busy I mean that there is nowhere to put the sails if you go with the battened sails. My old rig was just wrapped up around the mast which was perfect at the end of the day etc so that you did not have a pile of sailcloth in the boat with you. I did agonise over the whole thing and I can see the merit in that approach, I just wanted the things out of the way when they were down. The main is all nicely zipped away and in reality it is two topping lift clips and the gooseneck fitting pin (which is one of those irritating split ring things... made by Bastards Incorporated Pty Ltd incidentally) You are totally correct on a race from the car park to the bridge and back. It does take more to do. I guess the bit that over rode that decision was the 'fright' I had out in Hervey Bay one day. It did not take much imagination that day to see me in The Courier Mail, page one. The other thing that beats me around the head on this is that we bought a couple of those Hobie Adventure Islands. If you have a few hours free, you just chuck them in the water and go for a sail and go home. The 'boat' has always been a bit of a bigger project and this has not helped. But when I get to Tassie or Fraser, it will be better. So compromise is the word I guess. Dunno as we say. I wondered about telling everyone about this but there may be something here that interests someone. The cat ketch certainly looks better! Rob
  10. John Welsford did the whole thing. I sent him the sail plan drawing that Graham supplied which shows the centre of effort and centre of LR. I also did a fair bit of amateur checking of it all and initially I thought that John had it in the wrong place...(don't you love the irony in that sentence?) He clearly knows more about it than me and it has worked out perfectly. Yesterday with all sail in about 10-12knots there is gentle weather helm hard on the wind which is as he predicted. When I say gentle I mean gentle. Not like a Laser etc. John made a remark at one stage that the form of the hull has a lot to do with the true balance of the boat as it heels and his take on this project was that he thought it would be spot on and he was right. So that was my big fear at the outset that I would be dragging the rudder through the water like a barn door. So all good.
  11. Hello All, I have been absent for quite a while from the forum but thought would send you a few pictures of our Core Sound 20 with it's new rig. I had John Welsford draw me up a new sail plan for the boat about 2 yrs ago. I initially thought I wanted a 'modern gaff' rig but John was busy at the time and by the time he got to starting my job I came full circle and decided on a standard sail plan. Largely due to the thought of having to deal with local mast and sail makers who would have no experience in that type of rig. (nor me for that matter) So, once I had the drawing I then started trying to get a mast section etc that would fit the bill but that proved a bit harder than I thought. Most riggers were in the big boat $20,000 per job end of the market at a starting point and all their gear and experience was built around that. So the sections they had were all bigger than I needed and it got a bit frustrating sending off emails/plans etc to finally get out of them that it was not their cup of tea so to speak. So, driving past the sailing club I spotted a couple of Nacra cats so rang the factory in Brisbane and after a bit of discussion they did a great job on the rig and also had their preferred sailmaker come and do the sails. So it all finished up well. The final product is exactly what I asked for and works perfectly now that I have my head around the rigging etc. It does take a bit more to rig though. The jib in particular is a bit of a pain to rig as it has a luff zipper and when the boat is on the trailer it is not easy to manhandle as you are working above your head. If you put the boat in the water first then it is much easier. But the sail then falls in the water or in the mud. It has the luff zipper so you can use the roller furler drum. The main has lazy jacks and pre-rigged reefing lines down to the boom, which go forward to the mast and jam cleats. It works really well and this is the main reason I did the whole exercise. The problem I had was that the boat was not easy to reef or drop sail when sailing by one's self or when in rough conditions. Getting up on the foredeck really is not an option if you are being thrown around a bit and the wind is building. I found that if you lashed the tiller and the mizzen and then tried to reef the mainsail on your own it really was not easy. It was inviting me to fall into the water in my opinion. There was a thing in SCA where some guys had that experience in that they put too much weight on the bow and flipped their Core Sound from memory. I just did not feel confident that I could sort it out on my own if I got caught. My option was to rerig the cat ketch with a mast track and halyards etc but I just did not have it in me to go down that road. It just looked too hard. Maybe I am wrong on that but I had a look at a 17 with all the reefing lines etc and it looked pretty busy. I puzzled over the rig on the Bay Raider ie self tacking jib, gunter main rigged a bit further forward ie at end of deck in current 3rd mast hole but then needed a mizzen and bumpkin and all that. Could not face that either. So in the end I let the easiest route become the one I would follow. I don't think the boat is any faster really, I had an increase in sail area but it does not feel any faster. Down wind the old rig would have to be quicker wing and wing I feel, but am doing a whisker pole to get the most out of that. The boat runs so well downwind that I think the performance would probably be very little different over the type of sailing we do. If the jib gets annoying you roll it in. I had the mast rigged with the fittings for a spinnaker/screecher but that will have to wait for next year. I am going to shamelessly copy the bay raider which I pored over at the Hobart Wooden Boat Festival. So, the reason for all this is simple. We are booked in the Tawe Nunnugah Sailing Raid in Tasmania in Feb 13. http://www.lbt.org.a...nugah_2013.html (I went sea kayaking down that area in January of this year and was amazed at the wind we had so hence the need to have good reefing I feel.) It should be a lot of fun for a week, then a few days of wooden boat festival... That in itself is fun but having your boat in the harbour and sitting on board having a few refreshments at the end of the day should be good too. Anyway, it won't suit everyone but I am just putting it 'out there for discussion'. Not sure if the attachments have worked so here is a link to download the photos off Droplr. http://d.pr/f/67fG Cheers Rob Blackburn Lennox Head Australia.
  12. We have a CS 20 in northern NSW if you are up this way and you want to come and see us/go for a sail. Rob
  13. We had sprits all along and they were fine. In many ways they are the best and easiest. The problem was we got caught out in deeper water by some wind and despite having 2 guys on board and plenty of weight we got a bit of a fright. We got the main away and then were on mizzen alone but we could not go to weather at all well with the mizzen in the middle hole and we had a long way to go. (We got to shore and moved the mizzen eventually) So it made for a long day. The boat seems to drive well to weather with the masts in their normal spots but with reduced sail better, than the mizzen sail in the middle hole only if you have a load on. Also it is not easy in 25knots and waves mucking around carrying masts about. It is all fun though, I have enjoyed the whole process but feel that this offers a "Sea Pearl" type solution to the reefing issue. Rob
  14. Hello Chaps, I can understand if you think I have been a bit of the long way around on this but that is what happens when you start in one spot and are too mean to chuck out the sails and masts etc you have made. Finally got the roller reefing working on the CS 20 and on the weekend had the chance to try it in a gusty NE wind here in Ballina. It worked a treat. I have put up some shots that may be of interest to someone. There is a video here too. http://gallery.me.com/blackburns#100532 The nice thing about rolling up the sails is that it is really neat and tidy and there is no sails in the boat. I just could not come at the mess everywhere getting muddy and having lunch spilled on them etc.. if you have to put them down in the bottom of the boat. I also like being able to transport/store the whole catastrophe easier. I think now I will start on getting a lighter set of masts working as the way I have it now it is rather heavy as I have sleeved the bottom 1.5m of both of them due to me breaking the first ones. It really is a two person job to get them up safely. But over all it is better than the two other bright ideas I have had!!! Cheers Rob
  15. Kel the stainless man has finished my fittings. So here are some shots of the hardware. Old Greg the retired butcher with a lathe has done me up some hardwood 'donuts' to for mast fittings. They are not finished as yet, they need tidying up... Here are some shots. http://homepage.mac.com/blackburns/filechute/BOOM%20FITTINGS.zip The booms I have made are straight until the last 20% so that you don't get that big gap between the bottom of the sail and the boom. Then the boom drops down to the mast. Should work. But the problem remains, how does one give the mast man the amount of load on the mast so he builds one strong enough? Rob
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