Omer

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About Omer

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  1. Omer

    everybody doin' it?

    In my opinion, raking the mast forward a little (as shown in the picture) is also beneficial for the Dragons. Star boats do it regularly and succesfully.
  2. Omer

    Varnish peeling off in patches.

    Just the contrary. She was kept under canvass all the time except a month or two in summer.
  3. Omer

    Varnish peeling off in patches.

    I doubt it is epoxy. The guy who built it would not spend money on that :-) On the other hand i thought bare wood would absorb some of it so that when it peels off you would not be staring at bare wood. Or would you? Many thanks for all the good advice.
  4. Omer

    Varnish peeling off in patches.

    I have no experience with heat gun and i am afraid of scorching the wood. Since it is all in patches how do you apply a heat gun to an area where you have bare wood just next to it? Mind you if that was all uniform you would have bare wood next to it as you go along wouldnt you? ─░s there a safe way of handling a heat gun? Any info on two types of incompatible varnishes? What is a synthetic or urathane base varnish as opposed to natural resin based ones. I have an unopenned can of ─░nternational brand which i have mistakenly bought. What is it good for? After cleaning the mess should i use that? And if i do can i use a conventional varnish on top of that?
  5. I have a wooden dinghy built some 10 years ago. It has mahogany skin over plywood. I varnished it every other year with conventional varnish. Since last year all varnish is flaking and peeling of in patches like a skin, revealing bare wood. I do not know what kind of varnish was used originally and what is causing it to peel off. Could it be that it was a urathane based varnish and applied incorrectly? could it be that the conventional varnish i applied over it was not compatible with the original one? Since the parts not peeling off yet look good enough, i am not able to peel all of it and start from bare wood. so what can i do to get rid of it? The patches coming off is as thick as paper. so sanding it all would be quite an effort. Any suggestions?
  6. We are accustomed to boats being faster with longer LWL for displacement sailing conditions. This is a well understood subject of wave making resistance etc. Therefore rating formulas do take LWL as an iportant parameter. But with todays racing boats so eager to get up on a plane and given the right conditions, it is quite likely that a race can be sailed where boats are planing most of the time if not entirely. This is theoretically where LWL ceases to be a parameter for calculating potential speed. If this is so, what replaces it as the single most important factor? In other words for all sizes of boats in planing conditions and assuming they all have the same sail area to displacement ratio why should a boat with longer LWL be faster? Can a boat 30 or 40 ft overtake a 60ft boat, boat for boat? How can a planing windsurfer be as fast as a modern racer? Is a line honour possible for any size of boat in those conditions? How do rating formulas cope with that? If the wind speed is constant for all the boats, and if you can only go as fast as a percentage of it, or exceed as a percentage of it, then the smaller boats with lower ratings should have a huge advantage based on size. But that is not my point. If line honours are still with larger boats there should be some other important factors still. In short, is this also as well an understood subject as ''the bigger boat is faster in displacement mode'' as we are used to? I am certainly lost in this argument.
  7. Omer

    Which yacht is this?

    Hi JM, there seems to be some complicated gadgets hanging around the bow. The picture is not clear enough. What are they there for?
  8. Omer

    Bottom paint for fresh water

    What kind of a slime release agent out there to get rid of this?
  9. Omer

    The Curlew Restoration

    I am glad for that. Is there any reason why the other side doesnt come out as well?
  10. Omer

    The Curlew Restoration

    With all that beautiful mahogany it is a shame not to finish the hull 'Bright'
  11. Omer

    R2AK 2018

    RickW, as i remember from my Fluid Mechanics lectures some 20 years ago, the maximum power recoverable from the wind or any other fluid (coefficient of power) is limited by BETZ coefficient which is 59.3 % of available kinetic energy. This is the max. theoretical energy before all mechanical losses and electrical losses due to energy conversion. All wind turbines strive to get as close to this as possible only with high aspect 3 blade configurations. Also if i remember correctly 3 blade configurations are the only way to achieve max. efficiency and in reality it does not exceed 45-49 % Therefore, if the fluid mechanics theory has not changed in the past 20 years, i am intigued about your 84 % efficiency measure achieved by two blades. Are we talking about different criteria when quoting efficiency? I believe recovering energy from a flowing fluid is just the reverse of putting enegy from an outside source to a static fluid and the theory remains the same.
  12. Omer

    R2AK 2018

    Very nice. But i am puzzled by the choice of propellers. To me they are built for air not for water. I have never seen a slim two bladed outboard engine propeller . What is the theory behind them?
  13. Omer

    Trying to Buy a Boat

    I personally think this is stretching the ''insurable Interest'' too far. I would not want my employer or shareholders to have a policy on my life. Imagine the company is not doing good in any way for a number of reasons. Results are not there yet but waiting to happen. And the only way to save them is an untimely death of your darling yourself!
  14. Omer

    Trying to Buy a Boat

    No You cannot. The main issue is this. You can pay the premium of a policy on behalf of somebody else. But you cannot be the beneficiary if you do not have an insurable interest. You can pay the premium of a life insurance policy of a complete stranger if you want to. But you cannot collect anything upon death of that person. The same is true for a yacht insurance.
  15. Omer

    Trying to Buy a Boat

    First Law of insurance is that ''you should have an insurable interest.'' Just as you cannot have a life insurance based on somebody else's life other than yourself, you cannot insure a property which does not belong to you. It is quite likely that the seller no longer has a valid insurance and does not want to pay for it for a boat not used and not certain when to be sold. Ask him to get a policy. If the deal is done you can change the title of ''insured'' to your name, keep the policy and refund/pay the policy premium to the seller. If the deal is not done the seller can cancell his policy within 30 days and gets his money back. (or whatever the cancellation terms dictate)