Bruce Kieffer Posted January 25, 2022 Share Posted January 25, 2022 I'm trying to build a cedar strip canoe in Vectorworks using the same techniques that would be used in the real world. I do not want to take the time to try and create and add each curved 1/4" x 3/4" strip to the forms. I have the station molds created and mounted to the strong back, and I have created top view and side view profiles which I extruded and intersected solids. How do I take what I have and create an accurate plug (the shape of the boat as one solid object) of the boat? Quote Link to comment
markdd Posted January 25, 2022 Share Posted January 25, 2022 If you extract a NURBS curve from each of your “formers” and then use the Loft Surface tool in the first mode. You can select the create solid option when you have selected the profile curves. That should give you the main body of the boat. The bow and the stern segments can be made using extracted NURBS from the profile and each leading edge and then as long as they are connected, you can use the Create Surface from Curves command to give you what you need. Then you need to add them together and hopefully all will be well! (Hopefully!) 1 Quote Link to comment
Bruce Kieffer Posted January 25, 2022 Author Share Posted January 25, 2022 11 minutes ago, markdd said: If you extract a NURBS curve from each of your “formers” and then use the Loft Surface tool in the first mode. You can select the create solid option when you have selected the profile curves. That should give you the main body of the boat. The bow and the stern segments can be made using extracted NURBS from the profile and each leading edge and then as long as they are connected, you can use the Create Surface from Curves command to give you what you need. Then you need to add them together and hopefully all will be well! (Hopefully!) Thanks. I will give that a try. Quote Link to comment
Bruce Kieffer Posted January 26, 2022 Author Share Posted January 26, 2022 I've been playing with the lofting, and I'm not having luck. I have moved the loft points to get the best shape I can, but I cannot get it right. Maybe I need to create the NURBS curves differently? My NURBS curves do have different numbers of vertices. Quote Link to comment
Guest Wes Gardner Posted January 27, 2022 Share Posted January 27, 2022 @Bruce Kieffer I have tried from time to time to model boat hulls in Vectorworks and always had an issue at the bow and stern...you may want to try rebuilding your NURBS curves so that they do have the same number (and as few as possible) control points...honestly, I haven't tried it in a while... another trick is to only model HALF the hull and then mirror it over the the other side...another trick is to use as FEW stations as possible and still get the hull shape you're after... BTW, this is something Rhino does very easily and can produce some very good hull shapes (along with everything else on a boat) - here's an example of a design I'm working on... I haven't tried Blender yet but since it's open-source (free) it might be worth looking into... Wes Quote Link to comment
Bruce Kieffer Posted January 27, 2022 Author Share Posted January 27, 2022 I'm getting closer. This was done by lofting sections and then adding solids. It's close, but not perfect. I still need to try some of the suggestions you made @Wes Gardner. Thanks. 2 Quote Link to comment
markdd Posted January 27, 2022 Share Posted January 27, 2022 (edited) Hi @Bruce Kieffer Looks like you’re on the right track….. I’ve found as @Wes Gardnersuggests that keeping the vertex counts of the profile curves the same is the biggest way to get smooth results. The results you are getting look pretty good from here…. NURBS were conceived for just this kind of use so it would be gratifying if you felt that you were getting what you need. Edited January 27, 2022 by markdd 2 Quote Link to comment
Bruce Kieffer Posted January 27, 2022 Author Share Posted January 27, 2022 (edited) Benson S. is helping me with this too. He did a loft from polylines created with equal # of vertices, and his lofted shape looks real good. He split his shape down the keel line rather than across the beam as I have been doing. I think his way is better. I have more work to do. Edited January 27, 2022 by Bruce Kieffer 3 Quote Link to comment
Guest Wes Gardner Posted January 27, 2022 Share Posted January 27, 2022 @Bruce Kieffer ... yes, mirroring side-to-side is certainly the methodology that seems to work best! Looks good! You may also want to have a go at projecting waterlines, station/section lines and buttock lines onto the hull shape to insure a good fair hull that has no bulges or hollows like in the lower wireframe drawings... BTW, this was designed in Rhino and then cleaned up in Vectorworks for presentation... Wes Quote Link to comment
Bruce Kieffer Posted January 28, 2022 Author Share Posted January 28, 2022 (edited) I'm using a canoe a plan I produced for a magazine in 1991. That plan defines the shapes of the molds. That makes it very difficult to recreate a solid version of the canoe in Vectorworks. I was talking with Bryan G. tonight and I realized that this would be so much easier to start lofting the canoe shape, and then create the mold shapes. This is baby me back then! Edited January 28, 2022 by Bruce Kieffer 1 Quote Link to comment
Claes Lundstrom Posted January 28, 2022 Share Posted January 28, 2022 Using lofting of cross sections can be a nightmare in most NURBS based programs, and VW simply doesn't handle NURBS editing very well either, compared to most standard 3D CAD programs. No disrespect intended. VW's inability to nudge control points, and why you can't edit any number of control points in any number of objects at the same time remains a mystery. In my professional boat design program, I can easily tweak 500-1000 NURBS objects at the same time using a random selection of control points, and get an instant update of the lines drawing at the same time. Given the use of VW, you my consider using the following method: 1/ Generate some curves along the length of the boat, say three. 2/ Loft them into a a surface. Convert it into an interpolated surface having four by four controls in the grid (or thereabout) . 3/ Adjust the shape so that it looks reasonable. 4/ Add sectioning to see what the shape looks like. 5/ Repeat step 4 & 5 until the sections get close to the original cross sections 6/ Extract the cross sections to generate the updated buck shape cross sections. Quote Link to comment
Bruce Kieffer Posted January 28, 2022 Author Share Posted January 28, 2022 3 hours ago, Claes Lundstrom said: Using lofting of cross sections can be a nightmare in most NURBS based programs, and VW simply doesn't handle NURBS editing very well either, compared to most standard 3D CAD programs. No disrespect intended. VW's inability to nudge control points, and why you can't edit any number of control points in any number of objects at the same time remains a mystery. In my professional boat design program, I can easily tweak 500-1000 NURBS objects at the same time using a random selection of control points, and get an instant update of the lines drawing at the same time. Given the use of VW, you my consider using the following method: 1/ Generate some curves along the length of the boat, say three. 2/ Loft them into a a surface. Convert it into an interpolated surface having four by four controls in the grid (or thereabout) . 3/ Adjust the shape so that it looks reasonable. 4/ Add sectioning to see what the shape looks like. 5/ Repeat step 4 & 5 until the sections get close to the original cross sections 6/ Extract the cross sections to generate the updated buck shape cross sections. Great. This is what I'm saying. It would be easier to start by creating a boat shape, then create the mold shapes to match the boat shape you created. I did it the reverse only because I wanted to build my canoe in Vectorworks. Super hard to do. @Claes LundstromYour steps do give me a few ideas. Thanks. Quote Link to comment
VIRTUALENVIRONS Posted March 8, 2023 Share Posted March 8, 2023 Hello all, Coming to this post late, but it is an area I work in. The boat below was built in Vectorworks 2015 many years ago and rendered animated in CINEMA 4D. NURBS are not well documented and can be misleading. Extrude along a path and the 3D locus point are your friends in this area. Have you created what you need? 1 Quote Link to comment
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