nose diving riveira

Discussion in 'Powerboats' started by aussiebrian, Feb 25, 2010.

  1. tunnels

    tunnels Previous Member

    I hear what you are saying !! I drew all out full size and just shifting the prop back was a significant change in angle But if the hole has to be redone then its best to do everything possible to get the shaft down as lower angle as possible all at the same time . Its taken the guy 2 years to build so another few months to correct things will be a blessing to see it go good !!!
     
  2. rasorinc
    Joined: Nov 2007
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    rasorinc Senior Member

    On the Glen-L website under customer photos there is posted 18 different builder photos for the Rivera. As I mentioned in an earlier post why don't you contact them on the Glen-L forum and see if any of them had similar problems? Nothing I see there mentions your problem so talk to the 18 people who have built your boat with out your problem. Is there a reason you do not want to contact the very people who have built the very boat you have?????
     
  3. Hunter25
    Joined: Mar 2006
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    Location: Orlando

    Hunter25 Senior Member

    He did contact Glen-L directly and got a poor reception. Maybe their forum would be better.
     
  4. tunnels

    tunnels Previous Member

    I have a Glen -l book from 1959 and even way back then you couldnt get much satisfaction from them !!Had a friend that built a Tuffy but had a inboard . sOME THINGS NEVER CHANGE !!
     
  5. rasorinc
    Joined: Nov 2007
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    rasorinc Senior Member

    Both Glen L Witt and Ken Hankenson, Navel Architecs, have retired. The man who built the test boats and kits has retired. All requests for building information now go through the forum and have for some time. It is a very active forum with a large group of very helpful and knowledgeable people who will go way out of their way to assist other builders.
     
  6. Oyster
    Joined: Feb 2006
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    Oyster Senior Member

    Please clarify this comment. The group has a full service forum with builders actively participating. The company has been run by the same family since 1953 and actively participates each day in attempts to help builders.
     
  7. Oyster
    Joined: Feb 2006
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    Oyster Senior Member

    A little bit of followup for anyone paying attention, a complete and thorough attempt has been taking place for a long time with the builder. Glen L does its best to reply to any and all correspondance and there are plenty of varifiable details avaliable. If you would like to discuss the details and specifics of your setup and build beginning with some hard numbers fore and aft with your running gear, we can actually compare the real numbers to the plans and see if in fact or eliminate a deadweight issue in play here. Then we can also look at the bottom of your boat with substantive exchanges in hopes that we can figure out where we are here. There has been 18 completed boats of your design documented on the site and has not experienced your problem from what I have gathered in exchanges since this has been brought to light in the Glen L forum. Looking foward to some solid and substantive exchanges here.
     
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  8. TollyWally
    Joined: Mar 2005
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    Location: Fox Island

    TollyWally Senior Member

    That seems like a pretty good initial response to me.
     
  9. rasorinc
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    rasorinc Senior Member

    Nice posting Oyster. Stan
     
  10. Nova SS
    Joined: Mar 2010
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    Nova SS Junior Member

    Brian, I read your posts on the Glen-L site and here and this is what I think. Your prop is in the wrong spot. It is way too far forward it should NOT be 310 mm from the rudder. (this assumes the rudder is in the right location) That is over 12" which is way too much space(you only need enough space to get a prop puller in there). You drilled the shaft hole in the wrong spot. You need to re-drill the shaft hole, in the right spot, and re-rig the boat accordingly.(this will/should move the motor to the rear by about 8") I would have to believe that some of your imperial to metric conversions are a little bit off. This can cause little errors to stack up on each other creating a large error.

    So how did you drill the shaft hole in the first place? Did you mount the strut first and use it as a guide for the drill? Did you just measure and drill a hole without using the strut as a guide? How did you do it cause something was wrong. By drilling the shaft hole in the wrong spot that would put EVERYTHING else in the drivetrain in the wrong spot as the motor goes on the end of the prop shaft in this design.

    BTW, I also posted this on the Glen-L site as I'm not sure which one you will see first.
     
  11. Oyster
    Joined: Feb 2006
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    Oyster Senior Member

    One major advantage when doing business with Glen L, you are talking directly to the owner of the business or with a simple request on the phone to the receptionist, you can talk directly to the individual that when she was young and the business was up and coming was wearing diapers around the office and has taken over the reigns from her father. There is no one better to deal with. You will be talking directly to the person that has vested interest in sucessfull conclusions even when dealing with such a wide range of abilities of folks that build their own boats. If she does not know the answer, there are some yahoos that have passed the same route willing to answer any and all questions as long as folks reply in kind.
     
  12. rasorinc
    Joined: Nov 2007
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    rasorinc Senior Member

    I wonder if a simple set of electric trim tabs and some dead weight near the transom might allow this boat to reach speed.
     
  13. Nova SS
    Joined: Mar 2010
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    Location: Bedrock, Ontario

    Nova SS Junior Member

    I believe he said he has tried 150kgs (336lbs) in the rear and that didnt help. Possibly the tabs would make the difference but the "right" way would be to fix the rigging issues. Again this is JMHO
     
  14. Oyster
    Joined: Feb 2006
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    Oyster Senior Member

    Well the worse thing that someone can do is to add extreme amounts of additional deadweight to a small craft. Seas change each time someone takes a boat out. So how a boat handles on a certain day may also change on another trip. This is not a one off hull. I think we must stick to the known design and numbers, loads included. So there is plenty of presidence and proven builds to compare this particular hull to if we can just go back to the basics. Even with prior postings, sometimes its best to step back and then start over in an attempt to see the differences. Nova speaks about the differences and we need to actually confirm each part of the running gear once again including the motor slowly and compare IMO.
     

  15. Oyster
    Joined: Feb 2006
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    Location: eastern United States

    Oyster Senior Member

    I have been looking at the painted waterline on your photo thats been posted. You state in the photo that you have additional balast aft in the shot. If you look at the waterline thats showing slightly foward, with the balast in the boat in the stern, the waterline foward appears to be submerged. I am wondering if you have not placed the engine and running gear too far foward and you state that things are correct, and your waterline is below water with the stern balasted, its quite possible that you have some additional deadrise in the bottom and or your beam may be narrower than speced out around the windshield area. The boat also appears to have more flare in the windshield area which also may reinforce the notion that your bottom is narrower. This will cause the boat to sit down at the nose too which also causes some loss of lift in the bow or resistance when running on plane, getting worse the faster you go, causing the nose to surely steer the boat all over the place with less boat in the water aft.

    [​IMG]

    This is a sistership with a painted line.

    [​IMG]

    [​IMG]
     
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