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Need CAD type program

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Honestly, i'd just use a polygon modeler like Blender or alike. A polygon modeler takes more time to learn, but faster, especially with stuff that doesn't require straight lines. CAD programs are nice, but one thing i've learned is that I get way to fixated on precision. Real ships aren't hundred percent perfect nor are the plans you might use, because those are likely made by a fellow artist as well.

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CAD  =  computer aided design  * (the verb may be a different one)


You are starting with an existing plan and lofting hull components from it.

The actual design has been done.  You wish to replicate parts of that design at you target scale.


Lofting In Painter

I having been doing a lot of this (frame patterns for over 70 hulls).  I use a raster based program.  It does not do smooth curves as such. It does line segments.  The more segments, the smoother the curve.

Theoretically, what I get is a series of facets.  I patterns that I print out look smooth enough to begin with and even if it were facets, I can not get anything but a smooth curve on the wood from my sanders.

I use Painter 19 -  I already had an earlier edition from my time with 3D CG.  I could not justify the expense of Painter for just this part of its functions, were I just starting out.

GIMP is free, but it is a Photo Shop clone and brings a heavy load of functions with it.  Photo Shop will do it, but is not cost effective as a stand alone and a money sink on the Cloud if this is to be a continuing enterprise on your part.   Paint Shop Pro is about $50 +/-  and provided it can handle the potentially huge number of layers and large file sizes should be enough.

Painter 12 could not handle my file size in a single file - it added random green blocks when some threshold was exceeded.  Several smaller files solved that = Fore alone - one series, Aft alone  another series- lofting at 1:48= one file ,  reduction to 1:60 in another,  cutting the 1:60 frames into timber patterns a separate one or two files.

It makes a big difference depending the size of the ship.  A 118 gun liner stresses everything - all the way.  A pilot schooner is a snack.

Irrespective of your choice of raster program,  you will only be needing a relatively few functions.

SAVE - a function you will wish that you use more often than you do - unless you enjoy plowing the same furrow over and over.

COPY, PASTE,  CUT, SAVE   - big help is having a gaming mouse with programmable buttons for these.  I burned out the left click on several expensive brands.  I am getting excellent use out of a Redragon M711 Cobra Gaming Mouse  @ $20  I can burn thru a lot before I equal what a Logitech cost me and it is lasting longer to begin with.

For a brush - a thin line - (Painter buries finding a useful brush within an incredible number of options.)

Paint bucket fill tool - having frame lines as different colors helps in seeing what to cut -

With two timber faces on a pattern I cycle just 3 colors  R G B - in that order.  I know if it is R G,  red is always the midship face,  if it is G B , green is midship,  if it is B R , blue is midship. 

The placement  of the floor timber matters.  It is easy to get confused at the sander,  A system helps idiot proof things.

Rectangular Selection tool and Polygon Selection tool  cover this function for me - plus any erase needed

Magic Wand -  good for removing the background from a scan and making a layer transparent except for the lines of interest.

SCALE is vital  so is Rotate selection

I do not use many more functions than these.  Not much of a learning curve.


To begin, to save what I aim to print, I had select a canvas size that Windows Photo Viewer all not "adjust" for my printer.  I use pixels as the dimension units.

Home scanners to do not provide a 1:1 copy.  I had to determine an adjustment factor for every scan.  For MY Brother machine it is 102.5%.  The first thing I do to any scan when I import into Painter is to SCALE 102.5%. Before I do anything else - bad results if I miss doing this. 

Once I found a page size that Windows will leave alone, I scanned a transparent metric ruler and printed copies at ever more precise scale adjustments until I got an exact match.  This is tedious but necessary.

After importing a scan, adjusting the scale, removing the background,  the next fun ting to do is to rotate the scan back to vertical with your base  vertical Y line and X  baseline. 

The only concession I have made to CAD  is that I saved a long thin vertical  line using TurboCAD that I bought from an end cap display.   The finest line that Painter will do is 1 pixel wide.  I wanted thinner for within the program and a PNG import from TurboCAD provided that.  The patterns that I work with can't be any finer than what a point is from my ink jet printer so the precision is limited to Painter.


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Traverse PC and Generic Cad is what I have used for a very long time, Started out with a COGO on an IBM 1130, writing the program, punching the cards, feeding them into the card reader, waiting for them to reach the machine, monitor the printer as the program ran, tear off the printed sheet, recover the punch cards, debug and run it again, magic it was. We even acquired a drum plotter that printed all diagonal lines like a stair step, what a wonderful machine Punch Cards on an IBM 1130. The programs I first noted work for me and I have owned them a long time. You are getting some good ideas above, I stick to what I have, it is paid for and I am familiar with it, follow the above advice. Whatever you choose, it will be obsolete soon along with the software and data storage media, Store important stuff on acid free paper, you will be able to read it in 10 years, I expect a huge hardware change soon, it is past due.  image.jpeg.9e33ff6e29e82c50c2d5a2194a143052.jpeg


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I would definitely avoid the image editor (pixel) type programs like Photoshop, Paint, etc!


Select a cheap/free vector image program. This will allow you to adjust line widths and colors, and scale the drawing easily. They all will output images for printing/plotting at any scale.


There are basically two types of vector drawing programs. There are programs designed to make pretty pictures, with a minimum of precision drawing functions. Then there are true CAD (computer aided drafting/design) with a full set of precision drafting tools.


If you intend to build a historically accurate model use a CAD program. If you just want to throw something together that "looks like" a ship use a drawing program.

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Got ya beat, jud! I did the "punch card two-step" as an operator on IBM 360s on one of my working-my-way-through-college jobs at Standard Oil about 50 years ago. I remember, in those pre-internet days before "sexual harassment" and "hostile work environments," the programmers would work up printouts of the Playboy Playmate of the Month foldouts using ASCII characters as a "dot matrix" and print them out on tractor feed paper and pass them around. On a later college job, working for ITT Telecommunications when ITT was setting up the DARPA-net, the operators were sending that "ASCII art" out on the 33 and 100 KSR teletype terminals of what eventually became the internet. "Computer graphics" have come a long way since then, and I can't claim to be a CAD maven by any stretch of the imagination, but for modeling purposes, I find the old-time "ducks and battens" drafting technology is easier and faster for me, at least as far as what I need for ship models. I suppose it's different for younger folks who never learned "mechanical drawing" in high school when is was taught everywhere and for those who have mastered one or another of the CAD programs and kept up with their developments, often on the job, but when the contemporary hand drawn lines of period ships scale up to an inch or more wide at full size, I'm not sure I understand the point of trying to work with them at the "space age" tolerances of today's CAD software. 

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  • 4 weeks later...

The free version of Draftsight will cease to run after 31 December 2019... they have decided to charge an annual fee.

The hobby version will be $99 and does not do 3D.  It is strictly 2D

If you are able to spend more money there is a version that will do 3D.

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The main thing you need to understand about CAD programs is that they all have a steep learning curve. It will take months to become reasonably proficient with a new program. This is especially true with 3D CAD! If you have used a CAD program before it will be easier, but no two programs work the same way.


I have been using CAD programs for over 30 years - several different programs - so I am quite proficient with my favorite program (DesignCAD). But for simple things I still just make a sketch on paper rather than take the time to start the program. But for complex multi-part assemblies I always use CAD. Perhaps the best thing about working in CAD is that it allows you to "test fit" parts before actually building them. This has saved me a lot of time, materials and frustration!


To answer a point that was raised about the scaling of line widths when drawings are enlarged, it is true that the line width often scales pretty wide, decreasing the precision of the drawing. But, in most cases the ship builders used standard measurements (feet/inches/meters/millimeters). When you scale the drawing you can be sure that the dimensions are multiples of some basic measurement. And designers tended to use whole numbers instead of random fractions of the basic unit. After working with the drawing for a while you learn to guess the actual precise measurements from the overly wide lines. This is especially true when you have multiple drawings of parts that have to fit together. So the precision of a CAD program is useful even when the original drawing you are working from is a bit "fuzzy."


The same is true when you are trying to determine dimensions from photographs.

Edited by Dr PR
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  • 5 weeks later...

Re “I got you beat, Jud” from Cleet, I was punch card coding an IBM 1620 in 1962. Didn’t do any CAD but I developed a symbolic algebraic interpreter that would manipulate polynomial expressions. It was very slow! But then, the computer only had 64,000 bits (not bytes, bits) of memory. I was a sophomore math major at UNH  at the time.

And I had to hike uphill both ways in the snow to get to the computer center. And fend off dinosaurs at the same time. LOL


old yankee,

Ron Gove

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I've used DesignCAd for a couple decades, not nearly as long as the others. It is a reasonable price and offers discount on future upgrades. I generally upgrade about every 4 years. It does have a steep learning curve, but so do the others. I started by just leafing through the manual and seeing what each command could do, then start simple.

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I have been using DesignCAD (ProDesign) since 1988 in my work and for hobbies. I have also used about half a dozen other CAD programs, and they all have a steep learning curve for someone who has never done computer aided drawing. Check either of the links below to see how I use CAD in ship modeling.


The best thing going for DesignCAD (or any CAD program) is the free user forum. It is monitored by users all around the world and there are a number of us that check it daily. New users can post any question and get quick responses from very experienced users. And if the question stumps the users technical support will chime in.


I would advise anyone thinking of getting a CAD program to first look for the user forum and see how good the advise is and how fast it is forth coming. Are bug fixes and upgrades available free of charge, or do they cost as much as the initial program? Avoid any program that requires an annual fee for you to be able to communicate with other users on a forum or to get tech support (some programs charge thousands of dollars a year for forum access, tech support and updates to fix bugs).




Having said this, I must give a warning about DesignCAD right now. I am a beta tester for the program, and it is having problems. The best version in my opinion is the 2016 version (V26). The parent company fired almost all of the US programmers and developers a few years back and hired programmers in Russia! About the time those guys became familiar with the program they were fired and now the programmers are in Elbonia or somewhere. They are introducing bugs faster than they fix them, so the latest version (2019 or V29) really isn't useable.

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I see V25 is available on Amazon for $80..  Does that sound like a good deal?


Anyone ever use Turbo Cad.   I have a pretty robust version but haven't taken the time to learn it..


Any opinions if it would be worth the effort?

Edited by Gregory
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15 minutes ago, rshousha said:

I think it would be simpler to send the plans to someone who does this on a regular basis. Save the cost of the program; spend the time working on the model, not a piece of software you're going to learn in order to do something once every two or three years. 



That is assuming that one is only going to " do something once every two or three years ", in which case I agree..


However, I am using a laser cutter to enhance the kits I build, and hope to work on a scratch project someday soon.  


I am exploring the use of a CAD program to enhance my parts creating tool box, even though 2D is all I need right now.


Relatively low cost 3d printers and CNC tools are already a reality, and robust 3D software is essential to using these tools effectively.

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DesignCAD V25 is a good solid version with a minimum of problems. It is the version I use most often, and I have them all from the latest beta versions back to V15.


For the last few years they have been adding new features to position the program as an inexpensive 3D printer driver program. They have also added a lot of file format input/output features to allow files to be transferred to other programs. So, when the new programmers come up to speed (the beta testers are helping them with this) it should be a very nice program. DesignCAD has far and away the best user interface I have seen in any program, and I have been programming and using computers for 43 years!


I have used TurboCAD - a "light" version.  But because I was already very familiar with DesignCAD I found it very hard to use. It seemed to me that everything worked backwards from DesignCAD and it was harder to use. TurboCAD is more expensive, and upgrades can become very expensive.


You can get a 30 day free trial version of DesignCAD and play with it a bit. The user Forum is free and open to anyone, and you can ask all the questions you want. You don't have to register and you appear as "guest." But registration is free and easy and allows you to create a unique "handle" to distinguish yourself from other guests.


Rick is correct, however, if you really don't plan to use the program regularly. Learning any CAD program is a time sink that could be used for modeling. On the other hand, you might become addicted to CAD modelling (it's fun, and the models don't need more shelf space)! See my USS Oklahoma City CLG-5 thread listed below to see what you could be getting into! You have been warned!!

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  • 3 weeks later...

I was reading post #19 above and immediately thought of all the different things I use my 2D CAD program for besides drawings for ship models.


You never stop learning, so I believe a steep learning curve is no excuse if creating computer 2D drawings tickles your fancy.


The only two good reasons for me not to learn something knew is 1) it doesn't interest me in the least, or 2) I suddenly stopped breathing (YIKES).... this one never happened as yet.

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Over the last 6 months I have been learning FreeCAD to develop a 3D rendering of a fishing schooner. The interesting feature of the software is that it is parameter driven in that you can develop offsets which can be used in a number of ways - read from a constraint in a sketch, mapped in and out of a spreadsheet embedded in he tool and used to calculate a constraint.


The image scanned line drawing was imported into FreeCAD and the stations were plotted so that the intersections of waterlines and station profiles became parameter controlled locations which could be used to plot points in any view including the generation of the offset table. The waterline offsets were generated from the station offsets and splines were drawn to fit the offsets and compared to the scanned drawing so that any difference could be investigated. I had assumed that the plans were coherent in that the lines actually intersected and this validated it.


I have been disappointed in the Spline tool integration into parameter constraints but maybe I don't fully understand it yet.


The learn curve as with other CAD programs is quite steep but the documentation is free and all on-line and is reasonably complete given that this is open source software. There is still quite a lot of trial and error to learning.


After getting the 3D wireframe developed I have used Loft and Sweep functions to generate the hull, decks, bulwarks (no stanchions yet!) and monkey rails. I have also developed a very small 3D printed model using Shapeways to prove out the file transfer process.


If I get more confident that the approach is sound I may start a topic.

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Hi TonyM,


I also have tried out FreeCAD to model a hull. But until now that was not very successful.

I even have problems of making points from the waterlines in the half-breadth plan to coincide with the same points viewed in the station lines of the body plan.


About the splines in the sketcher, it is a fact that you can only make constrains for the control points and not the points of the spline itself.

There is however a workaround for this and it is explained in this video: https://forum.freecadweb.org/viewtopic.php?f=10&t=9364&start=420

It seems a lot of extra work to me.


So if you start a topic showing some hints on how to construct coincident points, I'm interested.


best regards,


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Thanks Kris,


Yes the Sketcher B-Spline tool is not what I wanted either but I have used the control points in the plan view to coincide with construction points from named constraint values in the cross section view which is my authoritative value. I only use the waterlines in the plan view to verify that something is not adrift in the coherence of the original plan and they are not used to construct the hull and decks which are done only from the cross section sketches.  This coincides with the way a real ship is constructed - the planking will go where it wants regardless of the waterlines.


However if you are using FreeCAD to develop plans this might not be accurate enough and you might have to trace the B-Splines to these control points. This is not ideal either.


I think the problem is in the working of Sketcher B-Spline with constraints and it can't reconcile both types of point. The Draft B-Spline is a different animal and I have not got that working with constraints at all.


It seems it might be worth starting a topic on FreeCAD. There is a lot of capability there but it has different behavior in the different workbenches.









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