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Peter HK

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Everything posted by Peter HK

  1. Displacement at designed water line. The total weight of boat, crew and gear for which the boat is designed will result in the boat floating at that waterline. It indicates what the designer thinks is a reasonable load for the boat as designed. Obviously this is a guide not an immutable law. Heavier loads (to some degree) would be OK especially in more protected waters. Lighter is always better for performance. Of course sailors always want maximum speed while taking along the kitchen sink. Cheers Peter HK
  2. I had the same problem. I think it is more likely now that we use non stretch line with small diameters- it cuts through the ply lamination more readily. I have a breakaway cleat on the downhaul and have adjusted it to let go a little earlier. I repaired it much as Paul described above but did add an extra. My rudder has a routed groove for the downhaul and it split at the base of the groove where it met the drill hole leading to the hole for the knot. At that point where the crack started I drilled a hole through the ply and epoxied in a piece of 6mm pultruded fibreglass rod (very tough stuff), thus preventing the line from easily getting into the laminations. Probably overkill. Cheers Peter HK
  3. In general pram dinghies offer the best load carrying/stability for length. The spindrift would be a better sailer but if you are going to motor/row then the catspaw would be a better choice...lighter & shorter. Coming from an inflatable however you might appreciate the catspaw 9- same weight as the spindrift but better load carrying and probably better suited to the 4hp motor. Any hard dinghy will less stable (in terms of initial stability) than your avon (for standing in to lift up the dog for example) so the bigger catspaw would again be a better choice from this point of view. Always compromises. Cheers Peter HK
  4. I'll try to help but hope I don't confuse you. On my boat I have permanent reefing lines - this includes a downhaul to the reef point on the luff. In the photos below you will see 4 lines led aft to cleats from blocks at the base of the mainmast. The one at the front of the mast (white/ red fleck) is the snotter...led all the way back to the aft cockpit. The one aft of the mast on the port side is a double standup block for the downhaul and reefing line...with just a downhaul to the tack this only needs to be a single block... blue line led aft to the cockpit. The one aft of the mast to starboard is the main halyard(yellow)...led aft to the forward cockpit which is where I reef the main. Ignore the black/red fleck line which is a reefing line. Cheers Peter HK
  5. I had a few drips of epoxy on the paint after painting and removed them easily with a scraper used gently. They weren't very adherent as the surface was smooth. Using a little heat (heat gun on lowest setting) can help if they are more firmly stuck. Cheers Peter HK
  6. Chick Ludwig said Designer, understood. Just want to clarify the reefing situation for Thrillsbe and others. On a boat without the third mast step, what would you do? Someone was telling me about a sleeve luff sail with a very deep pocket that would allow the sail to be lowered enough to reef. I have built a boat with the Wharram style large luff pocket...a gaff rigged schooner...and it certainly works well with the sail cloth collapsing into little folds very well. You can't use it with a sprit boom though because the snotter connection gets in the way....it only works with a standard boom (and is better with a gaff rig). Any sleeve arrangement around the front of the mast can't work well with a snotter attachment. You also can't have full length battens with such a pocket. Overwhelmingly the best arrangement to reef with a sprit boom is with sail track. My 2c worth Cheers Peter HK
  7. Dnjost said while we are discussing reefs and rigs, I am installing the rig with track and slides. Since I will have two reefs per sail, will i ever really be using the alternate mast step position? I now have two lovely mast/mizzen tubes, and am considering not going with the alternate position. Opinions? Does anyone use the third position? There is no point in the third position with proper reefing of main and mizzen. The ability to have a low COE rig will give more drive with less heeling force and you can still adjust for balance and heave to with the mizzen in tight. Too many advantages to consider the third reefing position not even thinking about the difficulty of dropping masts and shifting one on the water in 30 knots! Cheers Peter HK
  8. It possibly might do so. From the Gougeon brother's book: Plastic—Adhesion varies. If a plastic is impervious to solvents such as acetone, epoxy generally will not bond to it. Soft, flexible plastics such as polyethylene, polypropylene, nylon, and Plexiglas fall into this category. Hard, rigid plastics such as PVC, ABS, polycarbonate, and styrene provide better adhesion with good surface preparation and adequate bonding area. After sanding, flame oxidizing (by quickly passing the flame of a propane torch over the surface without melting the plastic) can improve bonding in some plastics. This suggests that chemical effects could be similar. I suppose a test bonding would give the answer. Flaming costs nothing and takes next to no time and comes with a recommendation from experts so I'd probably stick with that. Cheers Peter HK
  9. From memory the Gougeon brothers of WEST fame have recommended flaming the surface of pvc as well as sanding prior to epoxying. It only needs a few seconds (not burning). I have done it in the past and it seems to remove the waxy feel from the plastic. So far none of the epoxy/pvc bonding I've done has failed- about 15 years so far. FWIW Cheers Peter HK
  10. I would suggest ordering sails with reef points initially as it's easier and cheaper when making the sail rather than adding later. Then they are there if and when you want them at a later time. Cheers Peter HK
  11. ?Lagavulin- one of my favourites Cheers Peter HK
  12. The only 2 reasons I can see for the coaming to be above deck height are; 1 Aesthetics- I think it looks better 2 To keep rain out of the cockpit when camp cruising- otherwise, even with a cockpit tent, rain will track from the foredeck down the side decks and onto the cockpit seats and wet everything. This really only applies if you are trying to stay/sleep/cook etc onboard which I have not yet done (but intended to when I put the coaming on). So far I've always camped on shore with a tent rather than sleep onboard. Lennie - that cloth looks like chopped strand mat with a cloth backing- not something I'm familiar with. Cheers Peter HK
  13. I made some hiking seats for mine. They do make hiking more comfortable but not completely comfortable. They are tapered and rounded and at the inner edge are the same height as the coaming, about 3/4 inch. If I were to do it again I'd make the inner edge of the seat a little higher than the coaming as currently I still feel a little pressure on the back of the thigh where the coaming is and I don't get the full comfort benefit of the rounded inner edge of the seat. They do keep the crew weight in the right position in the middle of the boat though. Cheers Peter HK
  14. I did keep track of the hours just for interest when I built my CS17- from memory it was about 460 hours all up including rigging. I imagine the lapstrake hull would take 10-20% more. Cheers Peter HK
  15. Are you sure that was biaxial knitted fabric? It looks like that was woven cloth with the way the fibres shifted although the pics are a bit blurry. When doing an edge with woven cloth the piece needs to be cut on the diagonal (45 degrees) when it will conform quite nicely and the fibres will stay together better. I can't imagine knitted biax falling apart as it's held together by the stitching. Cheers Peter HK
  16. Great post It's missing the smiley face though Since the centreboard case is in the way it could only improve the upwind performance on one tack Cheers Peter HK
  17. I think what is meant is the same thing you mean when you said sleeve. I'd extend the top where there is no concern about strength as there may be with an extension at the bottom. If I could get a piece of al tube that fitted inside the current piece I'd use that...if not I'd use the same size tube and cut it longitudinally and compress it a bit to fit inside the topmast and the piece of tube you want to extend the mast with and rivet it all in place. Cheers Peter HK
  18. The mechanical properties do vary quite a lot between alloys and tempers. As an example a common alloy for tube here in Australia is 6060 T5 which has an tensile strength of 150 MPa whereas 6061 T6 (the standard alloy for marine use) has a tensile strength of 260 MPa...over 70% stronger. Cheers Peter HK
  19. I have 139 sq ft of sail on the standard CS17 (according to the sailmaker's computer program) as I ordered sails with battens and quite a large roach. I don't feel it's overpowered. I'm sure the ballasted boat will need all of the extra area. Cheers Peter HK
  20. I marked the varying bevels, which I took from the plans and checked on the boat, as a line on each side of the keel batten and marked the centre line on the batten itself and then attacked it with the power plane (caution- some experience with power planes advised) and finished with hand plane /sander. Took a bit of time to accurately mark it and 10 mins to shape it. I had taped the centre seam first (which is not actually necessary) which meant I could screw through the tape from above to hold the batten in place which was a bit easier than crawling underneath and was easy to do single handed. The fit will never be perfect so plan for plenty of thickened epoxy when gluing it down. Cheers Peter HK
  21. To add my 2c worth re reefing a small dinghy, I have a few suggestions: 1 A standing lug is quite a good choice and reefing is relatively easy...see the photo below of my shortened Welsford Golden Bay dinghy and the link to a short video of demonstrating the reefing system. https://www.youtube.com/watch?v=pvCr8EBKS64 2 Zippered luff can be done 2 ways. One way was the way I did it on my Bolger folding schooner which was based on Wharram's soft wingsail. With this the luff pocket is large so it acts partly like a wingsail with an aerodynamic entry, but also is large enough to compress down on itself forming a lot of little folds. Thus it can be dropped/reefed without any unzipping. The downhaul and halyard are best attached to the sail at the front of the mast. Here are a few photos The top photo shows the dropped sails with the luffsock compressed, the second photo shows the size of the luff socks (and that we needed more luff tension that day) and the third photo is from a Wharram site showing how the large luff sock collapses when reefed - this is the 4th reef. From memory I think Graham chooses a zippered luff with only a small luff pocket and unzips up to the reef point when reefing. Another alternative is to have a sock from head to reef point and one or 2 loops around the mast below the reef so the sail can drop easily. No doubt there are other alternatives. Cheers Peter HK
  22. Hi Fishman38 As I see it the bow eye needs to accept force in more than one plane. For example it needs to accept the winch force when first being pulled onto the trailer...this is usually with the bow being lifted up high until the trailer can tilt (if a tilting trailer) or until enough of the boat is pulled onto the trailer to line up the boat with the winch line. Also it might be used for towing at some stage with commensurate side forces. I follow the view that it needs a big enough U bolt set into enough timber and backing plate that any foreseeable pull will not result in failure. Also drilling bigger holes and filling them with high strength epoxy/filler and redrilling to the right size is a good idea as the timber is not subjected to the forces directly and is extremely well sealed from moisture. I usually finally seal with Sikaflex as it remains flexible and is very durable. HTH Cheers Peter HK
  23. 304 is typically used for bolts/threaded components as it is slightly stronger and better with respect to wear compared to 316. It does tarnish however whereas 316 stays bright. Cheers Peter HK
  24. Hi Wojtek I'll add my 2 cents worth The crease at the inner end of the battens could be excessively stiff battens but could only be determined with pressure under sail- do you still have a sharp transition when sailing? The luff creases are common when the sprit is to leeward and there is no tension in the sail- if still present when sailing then more snotter tension and more sheet should fix it by inducing mast bend. If not then is the mast too stiff (or the sail might have too much luff round). The creases at the foot of the mizzen I'm not sure about. ?more snotter tension needed ?more luff tension. Cheers Peter HK
  25. Just to add another point with respect to reefing the main- if you set your boat up with reefing in mind there is never a need to go onto the foredeck (a common misconception) as it can be easily done from the cockpit as I showed in this old thread (with you tube video). I leave all my lines permanently run and simply clip on with snaphooks so rigging is little different in time compared to rigs without reefing lines. There is no need to run the control lines down both sides as reefing the main is done head to wind anyway. http://messing-about.com/forums/topic/7063-reefing-cs17/?hl=%2Breefing+%2Bcs17 Cheers Peter HK
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