Jump to content

Recommended Posts

I was able to buy the student version of rhino with proof I was taking a class with udemy.com . If I remember correctly the class cost me like 20 bucks

  • Like 2
Link to post
Share on other sites

Autodesk Fusion360 is pretty good and has decent terms for personal use / hobbyists.

https://www.autodesk.com/products/fusion-360/personal

If you can prove some type of student status (or have kids that are middle school to college) then the student version is free too.

Alternately SolidWorks for students is $99/year.

Unfortunately the best CAD for lofting and complex shapes is CATIA.  But I have not found any way to get that privately (besides some very shady stuff on Ebay).  The CATIA generative shape modeling capability is why most aerospace companies use it for external loft lines.  I have yet to see if they put any of that capability in Solidworks.

 

 

  • Like 1
Link to post
Share on other sites

If you want to go fully free, Blender is a potential option. Its got a ton of functionality, but most of it is geared towards 3D renders, and not CAD.

Another option that is more esoteric would be OpenSCAD - its a programming based parametric modeling software focused on making solid models for 3D printing.

And on that note, for generating 2D sections of a 3D model you might be able to use an open source 3D printing software like Slic3r or Cura.

I've never modeled a boat, but it seems like a fun challenge. Good luck with your project!

  • Like 1
Link to post
Share on other sites

I use Multisurf, which I first got back in 1995 and have done thousands of designs and half a dozen builds from Moths to a 30' catamaran.

It's survived upgrades from Windows 95 through Windows 98, Vista, XP, and now Windows 10 and is still performing like a trooper.

It has all the functionality I need and I'll be devastated when it finally looses it's compatibility! :wub:

  • Like 1
Link to post
Share on other sites

FreeShip

https://sourceforge.net/projects/freeship/

which I believe was turned into...

DelftShip

https://www.delftship.net/

Unless I'm mistaken, they're both built on SubD rather than NURBS surfaces. I believe Fusion also uses SubD surfaces.

 

Otherwise, if you're going to be done in 90 days, just get Rhino. The demo is fully functional, then after 90 days save/export is disabled. Rhino was built on NURBS and now includes SubD. Rhino is a very well regarded tool by nav archs around the world. Plus Rhino is cheap and the license is properly perpetual. You could walk away from Rhino for 10 years, come back and as long as you still have the license key it will work.

https://www.rhino3d.com/

 

  • Like 2
Link to post
Share on other sites

Looked at Blender, it's going to be a bit of a learning curve, so I fired up "CADENCE" Virtuoso, (Integrated circuit layout) as I am familiar with it.

 

here's basic concept:

a modular dinghy 3-4 meters, that can be

  • Rowed
  • Motored
  • Sailed with inserted mast/daggerboard module
  • Stowed inverted & nested as a hard dodger

 

image.png.0e1cff1e0b6a852df2f3a47b06af0016.png

 

Prototype in 1/8" plywood, Stitch and Glue, with glass over,

external center and chine strakes, internal joint spanning stringers

sail and stern modules skin has lap joints.

rib as shown to provide bolting surface for modules.

Glassed in foam for flotation/stiffness

Simple "leg o mutton" or Gaff rig with Carbon tubes that double as sweeps

Need to figure out details of the lap joints to minimize leakage

Link to post
Share on other sites
3 minutes ago, LionessRacing said:

Looked at Blender, it's going to be a bit of a learning curve, so I fired up "CADENCE" Virtuoso, (Integrated circuit layout) as I am familiar with it.

 

here's basic concept:

a modular dinghy 3-4 meters, that can be

  • Rowed
  • Motored
  • Sailed with inserted mast/daggerboard module
  • Stowed inverted & nested as a hard dodger

 

image.png.0e1cff1e0b6a852df2f3a47b06af0016.png

 

Prototype in 1/8" plywood, Stitch and Glue, with glass over,

external center and chine strakes, internal joint spanning stringers

sail and stern modules skin has lap joints.

rib as shown to provide bolting surface for modules.

Glassed in foam for flotation/stiffness

Simple "leg o mutton" or Gaff rig with Carbon tubes that double as sweeps

Need to figure out details of the lap joints to minimize leakage

Have you given up on 3d then? 

If you wanted something as simple as that then Sketchup will do a better job & its dead easy to pick up. 

Link to post
Share on other sites
11 minutes ago, MiddayGun said:

Have you given up on 3d then? 

If you wanted something as simple as that then Sketchup will do a better job & its dead easy to pick up. 

Not given up, just did the 2D top down first to visualize the basic nesting geometry, and start thinking of the placements structure joints etc.

The screen shot is of several 100Vpower IC process layers, and scale is 10,000:1 (micron = decimeter) which is hilarious in itself.

I'll take a look at sketchup and see if that's a faster learn.

Link to post
Share on other sites
4 minutes ago, LionessRacing said:

I'll take a look at sketchup and see if that's a faster learn.

Sketchup is pretty awful at curved surfaces, but you could probably make it work for a chined dinghy with no rounded surfaces. 

Link to post
Share on other sites
1 minute ago, MiddayGun said:

Sketchup is pretty awful at curved surfaces, but you could probably make it work for a chined dinghy with no rounded surfaces. 

If I'm doing stitch and glue the surfaces will be pretty simple, could be flat to prove concept. I'd prefer something a bit prettier in long run.

in an ideal world, somebody competent would appropriate the design, make it more elegant and either publish plans or sell them.

in a really ideal world, I could just order it built, giving some basic dimensions such as the length/ width of companionway, offset and available "landing area" on cabin roof.

 

I've had a fabric dodger, which was $3k replacement quote.

I've had a 3.5 m RIB which I could wrestle up with a halyard and put on the foredeck. replacement quote $2-3k

if I could bash this together, and have it on a float to avoid fouling, tow or stow aboard for cruises that would be a good compromise.

Link to post
Share on other sites
4 hours ago, LionessRacing said:

so I fired up "CADENCE" Virtuoso, (Integrated circuit layout) as I am familiar with it.

Lol, i love it! Designing a sailboat in a pcb layout editor.

If 2D is your thing, QCAD is pretty good and has a cheap license. Great for working with or cleaning up DXF files.  We used to use it a lot for the lasercut parts in our 3D printers. 

Link to post
Share on other sites

I'll put in a plug for Fusion 360 as vastly more capable than Sketchup and easy to pick up, especially if you have any CAD background at all. An incredibly supportive community via the F360 forums is an advantage, as is being completely free for amateur or hobby use.

This guy uses the combination of Fusion and Meshmixer to unfold stitch & glue panels to make cutting patterns for a boat. Not too sure about the design example, but the method looks sound. 

The PCB layout program is a hoot- as it turns out we are here tearing our hair out trying to find someone to do the PCB layout for our newest design, hopefully in Altium but we can be flexible. Everyone in that business seems to be overwhelmingly busy. 

Like your idea- I'm interested in having something similar in a nesting dinghy & would like to see more. 

  • Like 1
Link to post
Share on other sites

I assume by motor you mean "motor will a small outboard" - because any boat that sails and rows well won't plane with a big motor.  I designed (many decades ago now in 1994) a nesting rowing/sailing dinghy that motors well with the smallest motor you can buy. At the time a 3.3 HP 2 stroke Mercury but now the 3.5 4 strokes are so heavy I'd recommend the noisy Honda 2 HP motors.

I'm not sure how the hard dodger over the companionway would work. Because think of the bow and stern sections as inverted boxes. If they connect just with a lip, then you have to work harder to make a watertight gasket and will need many fasteners. Maybe a recessed surgical tubing gasket will compress enough to be a gasket.

Here's a version of my design. I don't know what the builder did with the 2 lower fasteners - but it is held together by 4 x 5/16" bolts with wing nuts and rubber washers on both sides. The 2 upper fasteners are around the waterline if heavily loaded and the 2 bottom ones are of course well under water. The top of the bulkhead is well above the waterline. So you don't have to keep water from getting in between the 2 halves, just keep it from getting through the fastener holes. To work as a dodger you'd have to cut away to the red line or so, and then it becomes hard to keep out the water.

I think the extra section for a daggerboard is just extra work, but maybe it works for your idea of hard dodger. 

image.png.eaea6f53c0a8dbd07d42427682dd2f29.png

 

I sell plans (through an intermediary) for this nesting 11' dinghy. Feel free to steal ideas.    https://www.boatbuildercentral.com/product/nesting-dinghy-11-boat-plans-fb11/.  It rows really well. The sailing rig used was about the size of a Sabo or El Toro; about 35 sq feet. Any bigger and you need to hike and you can't hike on this boat without side decks.

image.png.0839b20dc0aa87a628d3f251fa81554b.png

I use Rhino because it tells me if a surface is developable enough to build from plywood. Any other CAD program that shows Gaussian curvature would do but Rhino allows me to loft a hull with just a few curves. If you use curves to loft a hull make sure they extend across the centerline, create the surface, and then trim to centerline. Makes much cleaner bows.

 

 

 

 

  • Like 3
Link to post
Share on other sites

The upside down middle seat on top, and aft seat on the bottom. When the 2 pieces are together the middle seat is a friction fit over the 2 joined bulkheads. The aft seat just sits on cleats in the stern.

Link to post
Share on other sites
14 hours ago, Zonker said:

I assume by motor you mean "motor will a small outboard" - because any boat that sails and rows well won't plane with a big motor.  I designed (many decades ago now in 1994) a nesting rowing/sailing dinghy that motors well with the smallest motor you can buy. At the time a 3.3 HP 2 stroke Mercury but now the 3.5 4 strokes are so heavy I'd recommend the noisy Honda 2 HP motors.

FWIW, the Suzuki 2.5 four stroke is only 30lbs, about the same as the Honda now-2.5 air cooled unit but much quieter. 

Link to post
Share on other sites

Interesting boat Zonker, the tubing gasket is an idea worthy of exploration.  
 

Haven’t done the structural engineering yet,  but was thinking of bolting through butted ribs much as you have done. 
 

willing to sacrifice ease of rowing, for better powered performance, happen to have a 2000 Honda 15 HP 4 stroke, at 100 lbs. 

had a further thought of a “console module” to allow wheel & controls vs. Tiller. 

Link to post
Share on other sites

If you want to build a planing hull, then it must be a fair bit stronger and stiffened. How to hold the 2 pieces together at high speed will be more intersting.

Shameless plug dept.  Take my GV10 dinghy design, fit a middle bulkhead and cut in two.

https://www.boatbuildercentral.com/product/fast-garvey-10-boat-plans-gv10/

Or just buy the plans and use them as inspiration and structural guidance. 

Link to post
Share on other sites
8 hours ago, IStream said:

FWIW, the Suzuki 2.5 four stroke is only 30lbs, about the same as the Honda now-2.5 air cooled unit but much quieter. 

The EPCarry electric outboard is about 15lbs and probably has enough power to push any 10’ light and well designed rowboat close to hull speed.  You can also position the battery for best trim.  I have over 3 hour runtime with a roughly 10lb battery (not the stock battery that they use). 

  • Like 1
Link to post
Share on other sites
13 hours ago, Zonker said:

If you want to build a planing hull, then it must be a fair bit stronger and stiffened. How to hold the 2 pieces together at high speed will be more intersting.

Shameless plug dept.  Take my GV10 dinghy design, fit a middle bulkhead and cut in two.

https://www.boatbuildercentral.com/product/fast-garvey-10-boat-plans-gv10/

Or just buy the plans and use them as inspiration and structural guidance. 

Had the thought of a mating bulkhead. Will look at design. Happy to buy plans. 

Link to post
Share on other sites
On 7/23/2021 at 11:31 PM, LionessRacing said:

If I'm doing stitch and glue the surfaces will be pretty simple, could be flat to prove concept. I'd prefer something a bit prettier in long run.

I don't think sketchup will unroll your surfaces to flat patterns, nor tell  you if the surfaces are developable.

Link to post
Share on other sites
25 minutes ago, Ncik said:
On 7/23/2021 at 9:31 AM, LionessRacing said:

If I'm doing stitch and glue the surfaces will be pretty simple, could be flat to prove concept. I'd prefer something a bit prettier in long run.

I don't think sketchup will unroll your surfaces to flat patterns, nor tell  you if the surfaces are developable.

Correct, it will not.

Not a difficult exercise to do a projection onto a flat surface though; or to set up a series of triangles for the panels.

-DSK

Link to post
Share on other sites

Just use Rhino, the skills are the same but Rhino is better for this sort of project, including the ability to unroll your surfaces very easily.

Commands to use...

Line (to setup an overall grid and any straight features)

Curve (to create plan and profile outlines of gunwale, chines, keel, etc))

Crv2View (project plan and profile views to create a 3D curve)

DevLoft/DevSrf

UnrollSrf

DupBorder (to create an outline curve from unrolled surfaces)

OffsetSrf (to give your surfaces some thickness)

RebuildCrvNonUniform (to simply the crv2view result)

Fair

CurvatureGraph (to see how fair your input curves are during point editing)

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...