Notes on Metal Boat Building Methods

Steel and aluminum boatbuilding. See: "Boatbuilding Methods", in left-hand column of the Home page, for information about alloys.

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niko
Posts: 13
Joined: Fri Apr 20, 2018 7:20 pm

Re: Notes on Metal Boat Building Methods

Post by niko » Tue Sep 11, 2018 1:24 pm

to add my idea to the subject of floating chambers:
I am planning to put plastic bottles into the floor and the aluminium seats through openings after all the welding has taken place. thought of it as the most "eficient" way to not have to seal all chambers and not being stuck with heaps of wet foam if I will get a leak to repair.
just an idea but till nobody tells me I am a fool and gives me a reason I will stick to the plan.

by the way. thank you Kevin for all your help on my project in panama.
due to very limited time I had to get an fellow Austrian welder into the project who has done a few boats already and has a cnc-cutter. so the project is underway but not so much under my influence. we couldn't wait another year to start business, but as soon as I get some spare time I will start my model and will try to get a little experience myself, cause I really like metalwork. (i will ad a few pictures of the project in the next days)
one thing I really haven't understood so far is making fair chine strakes. its quite complicated

Kevin Morin
Posts: 739
Joined: Thu Jan 24, 2008 11:36 am
Location: Kenai, Alaska

Re: Notes on Metal Boat Building Methods

Post by Kevin Morin » Wed Sep 12, 2018 9:51 am

niko, I fully understand the constraints of time and building boats! I used to build full time - for years and so I have had to get a few fishing boats ready for the commercial seasons and understand that your business needs take precedence over a do-it-yourself build!

Good luck with the resulting boat. Chine strakes are just like any other hull curve- I think I've gone over, in detail, (my friend, Yofish, thinks I go into too much detail??) to try and illustrate how to obtain fair curves from a series of points or take-off points if you're using an existing build as the guide or "fit-too" shape.

Anyway, when you get the time: the Forum enjoys images of builds, and more so when you can provide a short text explanation of the view of that aspect of the build's progress to help orient the viewers' understanding of the images.

Glad to be of any help that I can, looking forward to image posts of your boat as it goes together.

Cheers,
Kevin Morin
Kenai, AK
Kevin Morin

Sampot
Posts: 3
Joined: Mon Aug 27, 2018 9:48 am

Re: Notes on Metal Boat Building Methods

Post by Sampot » Tue Dec 18, 2018 12:59 pm

Kevin,

Thanks for writing this very interesting and detailed series.

I read in some other thread that you had a beginners guide to Delfthip. I recently purchased the Pro version and I'm learning the basics now.

Would it be possible to get your guide for Delfthip? It seems a bit difficult to get started with. I've used Solidworks in the past, and for my new boat project (my first one) I purchased a license for Fusion360. I'm hoping it'll be a bit more practical in top-down design than Solidworks.

Best regards,

Sampo
Helsinki
Finland

Kevin Morin
Posts: 739
Joined: Thu Jan 24, 2008 11:36 am
Location: Kenai, Alaska

Re: Notes on Metal Boat Building Methods

Post by Kevin Morin » Tue Dec 18, 2018 7:34 pm

sampot,
thanks for the kind words and Welcome to the Glen-L Forum.

I'm willing to send the very (VERY) old tutorial but must warn you the software- DelftShip Pro has relocated all the tools to differently organized menus/drop downs and the entire look and feel of the controls/tools are different from the ancient version I used when I was creating that 10 lesson beginners guide.

I do not think it will help much with your current learning- to be completely frank- since the imagery of the icons, menu locations and organization of the interface is so different now. (?) I haven't updated the tutorial I wrote for a friend more than a decade ago, now.... so while I'm willing to forward the files- I do have doubts about their usefulness?

Fusion360 can be useful for boat design but the "marine design tools" are not built in. So if you want to see what a small change in waterplane immersion will do to the LCB or Displacement? You have to make the changes to the 'object' in Fusion and then make all the calculations- unless you linked to a spread sheet with preformatted links to the file?

Delftship Pro and other marine design packages do these routine calculations for you all the time- continually in fact.

Also, as I last looked closely at Fusion- there is no developed surface or 'unwrap' surface feature - the sheet metal module may allow a triangulation of surfaces along a curved edge and that may allow some hull panel (hard chine/non warped surfaces confined to flats-cones-cylinders) outlines?

If all you're planning to use Fusion to do is fair a set of frames to strip plank or multi-layer plank ? then Fusion will do fine work - but won't answer any marine questions automatically.

k.morin@kmmail.net for direct request if you want the ancient tutorial files?

Cheers,
Kevin Morin
Kenai, AK
Kevin Morin

Sampot
Posts: 3
Joined: Mon Aug 27, 2018 9:48 am

Re: Notes on Metal Boat Building Methods

Post by Sampot » Wed Dec 19, 2018 1:39 am

Kevin,

Thanks, I think it might be still useful to go through you guide, even if it is dated. I'll send you an email.

Thank you for your comments on Fusion. I'm planning a wooden boat, so I won't need the sheet metal tools. My idea has been to model the hull in Delftship and import it to Fusion. And do the scantlings and all other internals there. I know in Solidworks I can treat the hull as a solid, split it at the waterline, and evaluate the CB, waterplane and displacement from the split solid. A bit cumbersome, but manageable. If that is not available in Fusion, I'll have to look at other options. I'm assuming Fusion would be able to give me the center of gravity of the completed CAD model with the materials assigned. The engine and other mechanics would only blocked in and their materials assigned to get the correct weight and center of gravity.

Would you have a recommendation on a software combination or a single marine design software? I can still get access to Solidworks as well. I have looked at some of the full marine design packages, but their pricing was (understandably) geared towards the professional naval architects.

Thanks again for your quick reply,

Sampo

Kevin Morin
Posts: 739
Joined: Thu Jan 24, 2008 11:36 am
Location: Kenai, Alaska

Re: Notes on Metal Boat Building Methods

Post by Kevin Morin » Wed Dec 19, 2018 12:06 pm

Sampot,
I understand your work flow using D'ship for the surface modeling and moving out to Fusion/AutoCAD to do the various structural details. And like you and many other personal use- marine software users- I'm always moving from one environment to another to do the full work of a design.

Low cost solutions will always be the various drawing environments that stand alone but have common file type outputs and inputs so the work done with tools only available in the 'other' package can be used to work (to some degree) on the files created or edited in the other.

So, by drawing in D'ship Pro and exporting various file types you can get that file to be "read" into AutoCAD, Fusion360, Solidworks, Rhino, and even Sketchup! I'm sure there are many other applications we could list that read in *.dwg or *.dxf files, but for the sake of discussion- as an example these are all separate products as you've noted. I've used D'ship into Acad, Fusion and Rhino but not always in the same time frame- so the file types out of D'ship were slightly changed- what exact 'export' type from D'Ship I used differed and so did the planned work flow.

I have not used a single, uniform method of work flow and have not had a single work flow method do all I wanted- so I've continued to experiment.

Now the HIGH end solutions. The boatdesign.net used to have a listing of all the marine design software which I recall but don't read that site much anymore. The conclusion I have now- is that buying the Rhino Marine add-in and buying Rhino would be the lowest cost dedicated - all in one package for marine design. If I were going to be doing full time design work- that's where I'd research first.

There are other integrated applications where all the various modules needed for the professional design office are incorporated - even DelftShip Pro offers various add-in modules for the professional designer. So the other lower cost route to the High End software is to explore buying only the base module and seeing how many features are currently offered for what cost.

In the mean time; I use D'shipPro for the lines and main surfaces and export to SketchUP to do the CAD work. But... i have not tried to provide 'cut files' for NC equipment from this combination. To do that you'd have to confirm the lines' end points were close enough for NC or CAM interpreters' recognition- another entire discussion.

Cheers,
Kevin Morin
Kenai, AK
Kevin Morin

Yofish
Posts: 98
Joined: Wed Jul 04, 2018 9:40 pm

Re: Notes on Metal Boat Building Methods

Post by Yofish » Sat Dec 22, 2018 1:12 pm

FWIW, I'll toss in my two penny's and make a pitch for ProSurf from New Wave Systems (http://www.newavesys.com/) for hull design, which employs NURB's. Maybe I already have, but don't remember....

I've used it since 1998 and I don't have anything bad to say about it. The GUI hasn't changed an iota since. It is not free, but rather inexpensive for what you get considering Rhino doesn't do anything better for the small builder. Having said that. I've built from 8' to 40' using it. Of course, as Kevin mentions one needs a 'general purpose' CAD program if you intend to plot anything complex like plating with piercings, layout lines etc. I use DesignCad by IMSI as it is cheap and more than capable. Sketcup 7 (the last free capable version) is nice to view simple renderings.

ProSurf basic is 95 bucks, DesignCad 2-D, 50 bucks and Sketchup 7 for free. Sometimes more is not better and much can be obtained for little.

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