Hull alignment and crossbeam position - Wharram Builders and Friends2024-03-29T14:27:46Zhttp://wharrambuilders.ning.com/forum/topics/hull-alignment-and-crossbeam-position?commentId=2195841%3AComment%3A127825&feed=yes&xn_auth=noExcuse me before I began bui…tag:wharrambuilders.ning.com,2015-03-19:2195841:Comment:1280082015-03-19T02:33:17.287Zjohn jameshttp://wharrambuilders.ning.com/profile/johnjames
<p>Excuse me before I began building a James Wharram catamaran I did not know a millimeter from a centimeter and I still don't very well, I was thinking 12 mm alignment rather than centimeters. Certainly as a builder this is probably too much of a an error And as a builder I would not tolerate it However that's not exactly the question;Cute is not building a boat he's got it hauled out in Malaysia somewhere The temperature is probably 80 or 90° Probably his box of hand tools sitting in the…</p>
<p>Excuse me before I began building a James Wharram catamaran I did not know a millimeter from a centimeter and I still don't very well, I was thinking 12 mm alignment rather than centimeters. Certainly as a builder this is probably too much of a an error And as a builder I would not tolerate it However that's not exactly the question;Cute is not building a boat he's got it hauled out in Malaysia somewhere The temperature is probably 80 or 90° Probably his box of hand tools sitting in the sun are too hot to even touch. He's doing maintenance work. As long as he owns the boat he'll do maintenance work, I believe the boat is quite a new to him ,It's a piece of maintenance that would be extremely aukward and time-consuming to repair. Personally I don't think it would make much difference anyhow. That's why I say go sailing don't worry be happy.</p> It might be that the hulls w…tag:wharrambuilders.ning.com,2015-03-18:2195841:Comment:1277622015-03-18T15:03:45.104Zboatsmithhttp://wharrambuilders.ning.com/profile/qe0j3ojqb10
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<p>It might be that the hulls were planked up with a twist in 1 or both hulls. This might make it impossible for everything to line up. </p>
<p>If you can't plumb up the stems and stern posts at the same time this would indicate twist in the hull. </p>
<p>Then you will have to decide what to favor. Nothing is ever perfect and these boats are more tolerant of poor craftsmanship than some others.</p>
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<p>It might be that the hulls were planked up with a twist in 1 or both hulls. This might make it impossible for everything to line up. </p>
<p>If you can't plumb up the stems and stern posts at the same time this would indicate twist in the hull. </p>
<p>Then you will have to decide what to favor. Nothing is ever perfect and these boats are more tolerant of poor craftsmanship than some others.</p> i would change it. you are si…tag:wharrambuilders.ning.com,2015-03-18:2195841:Comment:1279452015-03-18T12:18:52.162Zwakataiteahttp://wharrambuilders.ning.com/profile/wakataitea
<p>i would change it. you are since a few years now on this boatyard. this little more work will not change a lot but i belive that the boat will be better .... just do it... and don't worry after it anymore..</p>
<p>hans</p>
<p>i would change it. you are since a few years now on this boatyard. this little more work will not change a lot but i belive that the boat will be better .... just do it... and don't worry after it anymore..</p>
<p>hans</p> The 12cm off parallel over 46…tag:wharrambuilders.ning.com,2015-03-17:2195841:Comment:1279282015-03-17T13:16:48.823ZRob and Beth Boasehttp://wharrambuilders.ning.com/profile/RobandBethBoase
<p>The 12cm off parallel over 46ft is 12cm too much in my view. That amount of toe in or toe out must affect performance and if nothing else would create some interesting whirlpools behind the boat at speed! </p>
<p>To set our Tiki 30 hulls square and parallel we first marked out a square on the floor(using the 3,4,5 method).</p>
<p>Then marked out the required measurements on the floor and used a plumb-bob suspended from each stem and stern post to line up with the marks. Our building frames…</p>
<p>The 12cm off parallel over 46ft is 12cm too much in my view. That amount of toe in or toe out must affect performance and if nothing else would create some interesting whirlpools behind the boat at speed! </p>
<p>To set our Tiki 30 hulls square and parallel we first marked out a square on the floor(using the 3,4,5 method).</p>
<p>Then marked out the required measurements on the floor and used a plumb-bob suspended from each stem and stern post to line up with the marks. Our building frames were on castors so it was easy to manoeuver the hulls around. We managed to get the hulls square and parallel within a couple of millimetres. I admit it would be more difficult with the hulls of a tiki 46.</p>
<p>Rob</p> Hello cute
Sorry but I can't…tag:wharrambuilders.ning.com,2015-03-17:2195841:Comment:1278252015-03-17T09:32:41.054ZBertrand FERCOThttp://wharrambuilders.ning.com/profile/BertrandFERCOT
<p>Hello cute</p>
<p>Sorry but I can't understand exactely the modifications of the builder. Can you post a few pictures?</p>
<p>For me 12cm is too much but to reduce it you have to modify all the beam holes!</p>
<p>As I explained in my Tiki46 building blog, I think more logical to have only holes (reinforced by a stainless tube) in the beams instead slots and to have the slots in the bulkheads. Since her launch I sailed 18000NM mainly offshore without…</p>
<p>Hello cute</p>
<p>Sorry but I can't understand exactely the modifications of the builder. Can you post a few pictures?</p>
<p>For me 12cm is too much but to reduce it you have to modify all the beam holes!</p>
<p>As I explained in my Tiki46 building blog, I think more logical to have only holes (reinforced by a stainless tube) in the beams instead slots and to have the slots in the bulkheads. Since her launch I sailed 18000NM mainly offshore without problems.</p>
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<p>Bertrand</p>
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<p></p> Lining up the hulls parallely…tag:wharrambuilders.ning.com,2015-03-16:2195841:Comment:1276402015-03-16T23:11:19.560Zboatsmithhttp://wharrambuilders.ning.com/profile/qe0j3ojqb10
<p>Lining up the hulls parallely, plumbly, and square is a bit of work. It is certainly possible that someone stopped at fugingudnuf.</p>
<p>120 mm is 4+ inches is way more than I would allow. We plumb up the sternposts and stems. We measure elevations and centerline beams at the 4 corners. Then we measure the diagonals for squareness. Sometimes it is a little fussy. We usually are under 1/8" 1.5mm. </p>
<p>It looks better when things are straight. Probably faster…</p>
<p>Lining up the hulls parallely, plumbly, and square is a bit of work. It is certainly possible that someone stopped at fugingudnuf.</p>
<p>120 mm is 4+ inches is way more than I would allow. We plumb up the sternposts and stems. We measure elevations and centerline beams at the 4 corners. Then we measure the diagonals for squareness. Sometimes it is a little fussy. We usually are under 1/8" 1.5mm. </p>
<p>It looks better when things are straight. Probably faster too.</p>
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<p></p> One cannot build a boat perfe…tag:wharrambuilders.ning.com,2015-03-16:2195841:Comment:1278982015-03-16T21:10:30.899ZBradhttp://wharrambuilders.ning.com/profile/Brad
<p>One cannot build a boat perfectly. Errors in measurement will be made but most will cancel each out in the long run. That does not mean we should be sloppy in boat building. If the two hulls are aligned the boat slips through the water with the least effort. Does it matter if we can go a quarter knot faster? In a thousand mile journey? Does it make a difference?</p>
<p>One cannot build a boat perfectly. Errors in measurement will be made but most will cancel each out in the long run. That does not mean we should be sloppy in boat building. If the two hulls are aligned the boat slips through the water with the least effort. Does it matter if we can go a quarter knot faster? In a thousand mile journey? Does it make a difference?</p> Hi Cute,
you have about 0.5…tag:wharrambuilders.ning.com,2015-03-16:2195841:Comment:1278932015-03-16T14:00:22.236ZRoberthttp://wharrambuilders.ning.com/profile/RobertB
<p>Hi Cute,</p>
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<p>you have about 0.5 degrees of toe out, which is regarded as acceptable toe out for many cars, so I would not worry about that if it is going to be a lot of work to change. As far as I can tell there is no list of acceptable tolerances in the Tiki 46 plans; I am building hull number 43. I work to the tolerance of what is not easily visible on the scale of the boat, this helps to get things done and keeps one from going insane obsessing about the fact that things do…</p>
<p>Hi Cute,</p>
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<p>you have about 0.5 degrees of toe out, which is regarded as acceptable toe out for many cars, so I would not worry about that if it is going to be a lot of work to change. As far as I can tell there is no list of acceptable tolerances in the Tiki 46 plans; I am building hull number 43. I work to the tolerance of what is not easily visible on the scale of the boat, this helps to get things done and keeps one from going insane obsessing about the fact that things do not quite work as the plans describe (probably due to an earlier measuring error ).</p>
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<p>I would keep the interior level and forget about the stem and the stern being vertical. Do try to get all the beam pads to make contact, if needed redo or modify them. This is important to distribute the loads evenly into the beams and hulls.</p>
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<p>Robert</p> (A) Did you get the building…tag:wharrambuilders.ning.com,2015-03-16:2195841:Comment:1277062015-03-16T12:04:29.178ZGeorge Rayhttp://wharrambuilders.ning.com/profile/GeorgeRay
(A) Did you get the building plans with the boat and if so they should reveal the thoughts of the designers on appropriate alignment/precision. (B) there are a few members with very serious building/sailing credentials whose opinions I would particularly seek out ( Ann-Neville & BoatSmith come to mind) (C) Email designers<br></br>
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My personal thoughts: (1) parallel hulls require the least energy to push through the water , (2) plumb hulls with flat/horizontal surfaces at rest may not be…
(A) Did you get the building plans with the boat and if so they should reveal the thoughts of the designers on appropriate alignment/precision. (B) there are a few members with very serious building/sailing credentials whose opinions I would particularly seek out ( Ann-Neville & BoatSmith come to mind) (C) Email designers<br/>
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My personal thoughts: (1) parallel hulls require the least energy to push through the water , (2) plumb hulls with flat/horizontal surfaces at rest may not be best. Boat sail with slight heel and flat surfaces hold some water rather than drain<br/>
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John James has a point to consider, "don't let the perfect be the enemy of the good". The trick is knowing what is good enough. 1 CM serious I think Brad is…tag:wharrambuilders.ning.com,2015-03-15:2195841:Comment:1277922015-03-15T23:23:00.298Zjohn jameshttp://wharrambuilders.ning.com/profile/johnjames
<p>1 CM serious I think Brad is taking his James wharram plans a little too seriously.I dont Think the ocean is going to be that fussy 10 centimeters over the 46 foot lengths of the boat is not going to make any difference. I would think it would be a very time-consuming troublesome thing to correct---perfectionism is a particularly cruel form of mental instability</p>
<p>1 CM serious I think Brad is taking his James wharram plans a little too seriously.I dont Think the ocean is going to be that fussy 10 centimeters over the 46 foot lengths of the boat is not going to make any difference. I would think it would be a very time-consuming troublesome thing to correct---perfectionism is a particularly cruel form of mental instability</p>