Going From A 2D Drawing To A 3D Printed Part Tutorial using SketchUp

[thibaultron]

For my "stuff", I model it full size, then rescale it when I send it to the printer. I'll have to look into Blender.

 

My tutorial is intended more to teach how to use SketchUp, rather than as a drafting lesson. I wanted to show a few tricks I'd learned along the way, also.

 

Here's a shot of a piece of equipment I'm designing for one of my model railroad locos. It is a conversion set to modify a Bachmann 2-8-0 to a Santa Fe prototype. I could have built it long ago, but enjoy the challenge of CAding/3D printing it. If it works out I plan on making it available to others. It's an oil bunker for the tender, with a new dome for the locomotive. The second dome is for me to trial fit first, so I don't ruin the "good" one.

 

One thing that will come out of it is a set of accurate oil fill hatches for Santa Fe locos. Most production models have incorrect ones, even the Brass locos. I have several tenders that I need to upgrade. Also the 2 tool boxes are missing on most SF loco models. I will have to stretch/shrink some of the dimensions to fit each loco, but I have the basic models to start with.

 

It may be too complex, with all those rivets on the side, but I'm interested in seeing if it works.

[fnkershner]

I have recently gained access to a workshop with several 3D printers. They use TinkerCAD as the software. I have been playing with TinkerCAD. So now I have some questions and maybe you can help. Is there a way to scan a part of the plans for one of my model kits. then pull that scan into TinkerCAD or some other program and then convert to a 3D drawing so that I can try to print it?

[thibaultron]

I've never used TinkerCAD, perhaps it can import a JPEG, or other graphic file? You could then trace it, in the CAD, and go from there.

[fnkershner]

Ok so I can scan the plan sheet and create either a Jpeg or Pdf. then import to the CAD S/W. and you are saying that in order to convert to a CAD file I will have to trace the imported file. And then convert from 2D to 3D?

 

PS TinkerCAD is by Autodesk.

[thibaultron]

Yes. There is no usable software to automatically "trace" the graphic to a CAD format. There are lots of programs that say they will, but none that do even an adequate job of it.

[jud]

I used my 2D surviving software to generate data and rectangular coordinates in the following format, Alpha Numeric Point Numbers, X, Y, Z and descriptor to produce DFX drawings of Each Frame for my LST. I obtained my Z coordinates by rotating my drawing and manipulating the X and Y coordinates using different point numbers to keep it separate, then manually entered the Z component in my main data base. Question, these coordinates are useful to me using my 2D software, were I to upgrade to 3D software, is this data base and resulting 2D DXF drawings usable in such a program or do 3D programs use something other than a rectangular coordinate system for endpoints?

jud  

[thibaultron]

X,Y,Z in 3D, so your data will transfer.

[Nirvana]

Ron, thanks for the tutorial even though I have been using SketchUp ever since it came out and gone through several owners, Trimble the last one for now.

I have learned something new and will try to in-cooperate the 3D printing as well.  

 

[fnkershner]

Ron - Per is hiding his brilliance. He and I worked together yesterday. We installed TurboCad and we scanned the plans to a JPG and successfully imported to TC. Now I am told there is a Tracing function in TC. Now all I need to do is find it. Thanks for all your help.

Edited December 24, 2017 by fnkershner

[thibaultron]

Forget the "Tracing" function! My DesignCAD "Trace" (by the same company), is not usable, for precision work. No company makes one that works well, enough. Here is an example of a trace of part of a scanned drawing. The trace is shown in green. Its better to bite the bullet, and manually trace the drawing.

 

[fnkershner]

Rats, Ron you are correct. I have been playing with TurboCAD. I started with the 64 bit version. but I am told there is no tracing function in this version. So I began a wider search. My results agree with your comments. So given my goal of 3D printing what S/W would you recommend? I guess I will start over. no need to learn TC. It is a powerful program but it will not do what I need. Thanks for saving me $150.

Edited December 30, 2017 by fnkershner

[thibaultron]

I use DesignCAD 2016 for general drawing and non 3D printing, and SketchUp for the 3D printing. You really need a good regular CAD program for going from drawings to ship frames etc. I use the 3D features of DesignCAD to check that the frames are "fair", and to double check other features.

 

For example: Here is my redrawing of an old out of production kit. The frames as shown in the original drawing are very incorrect for the aft frames! I don't even know how anyone built the original kit, unless the supplied frames differed greatly from those shown in the drawing. Here are the before and after frames:

The colored lines are what I got after using the 3D features to layout and draw waterlines.

 

Here is the 3D layout with waterlines drawn:

 

One thing that most of the CAD programs have, that SketchUp lacks is the ability to draw a smoothed curved line to match fixed points. With SketchUp you can draw straight lines between points, but not a smoothed curve. That is how I got the final frames. With the frames laid out in 3D I drew the curve between the frames and looked for dips or bulges. I then moved the offending points in or out until everything looked smooth. I the case of this boat I generated the aft frames using the fore frames, the deck outline, and the transom as data points to start. Now that I have good water lines, I can also generate intermediate frames, if desired.

 

If TurboCAD costs $150, check out DesignCAD, I think that it runs around $100. I've been using it, in various versions for the last 20 years or so. You definately what a 64 bit CAD.

[Nirvana]

Ron, 

open up the extension library, there are tons of add-ons for various "curves".

As for inspiration here is a yacht done in SketchUp

 

There are a lot of tutorials in this matter, Bing or Google it.

I found many doing so.

Edited December 29, 2017 by Nirvana

[thibaultron]

I know there are a lot of curve extensions, but I haven't found one that actually creates a smooth curve that follows a set of points. Lots of Besler curves, but not a spline type. Do you know of a spline type extension?

[Maury S]

TurboCAD has a spline function.

Maury

[fnkershner]

Ron - I have an update on my journey. As I mentioned I was trying to find a way to 3D print my Carronades on my Syren. I started by scanning the plans into Turbo CAD 64 bit. I would have used Sketchup but it did not have a tracing function. In the process of learning how to do this. I learned that first Turbo CAD did not have a tracing function. And 2nd as you mention, the tracing function is not very good anyway. But as part of my Research I joined a Forum on Turbo CAD to ask questions. One respondent asked me to post my JPG so he could see what I was trying to do. Yesterday I went back to the forum to see if there was any more suggestions. And I found that some one had taken my scan and created the 3d picture. Now all I need is his file and I can do my 3D print. It will also be a good chance to learn what he did.

[fnkershner]

Ok further update on my journey. I attended my class yesterday. The class was billed as Tinker CAD & 3d printing. I found that all 3 of the printers in the workshop were down for 1 reason or another. I also found that the TinkerCAD training was geared for a beginner. Someone who had never seen CAD or a computer. So frustration for me. I explained my project. I also asked why TinkerCAD instead of SketchUP. He said tinker CAD was easier to learn and teach. But he agreed SketchUP was better. Then he tried to sell me his services. He offered to design my Carronade and print it for a price. That was not my plan. I wanted to use this opportunity to learn CAD and 3D printing.

 

So My question to you is can you suggest SketchUP training. Most of what I see on the web is intended for a business and priced accordingly. I don't see much for the hobbyist. I will continue my search for access to a quality 3D printer. Grrr

Edited January 7, 2018 by fnkershner

[Nirvana]

Floyd, there is a whole bunch of free classes on-line to learn SketchUp and be efficient in it. But for what we are doing go to Sketchucation.com,  sign up and you have access to a huge library.

Many of us using SketchUp learned it by trying by error. Many (not me) are today professionals in various design fields.

SketchUp program cover a huge field other 3d program cannot compete with.

Maybe I should set up an on-line class for you 

[CDR_Ret]

Floyd (fnkershner),

 

I would be happy to provide some Sketchup coaching for your project at no charge. I am a retired professional educator and enjoy helping people learn new things. What you want to do utilizes just basic functions of Sketchup. Solid objects created in Sketchup are inherently manifold and 3D-printable unless you break the envelope or introduce extra geometry in an uncontrolled fashion.

 

Please PM me with your email address if you are interested.

 

Terry

Colorado Springs, CO

[thibaultron]

Latest 3D printing project:

An oil bunker for an Bachmann Spectrum 2-8-0 HO locomotive, two tool boxes for the tender, and a new dome for the boiler. This model has two domes, the 2 part on is for initial fitting, and the complete dome for the final install. Over a thousand (1 1/2" diameter scale) rivets, and yes the total length of the parts as shown is 3.56". The slots in the side of the bunker are to fit over the existing "walls" of the coal bunker (after the bottoms are cut out of the slots). This leaves the ability to change it back to coal, much as the Santa Fe railroad did in real life. The oil bunker was a tank that sat in the coal bunker, instead of the coal load. I've spent waay too long designing this, but it was an interesting exercise. This is version 2.0, the first part was just for a trial fit, and ended up needing a few dimension changes, as expected.

The first printed part had damage to the rivets were the Shapeways tech pried it out of the printer. In the end the 3D printed part is probably too fragile for production selling. If I decide to sell this, I'll probably have to use the final part as a master for resin casting.

Why the 2 part hatches (base and cover)? I plan to sand the cover to a scale thickness, hence the recesses in the bottom of the covers.

[fnkershner]

I want to Thank everyone who has contributed to this discussion. For me it has been an exciting and steep learning curve. but very rewarding. Terry - I want to apologize I did not see your post until recently. If you go to my Syren build log you will see that I have temporarily solved my immediate challenge. But I have dove much deeper. I am now using Fusion 360 to make designs for 3D printing, CNC, & Laser cutting. I have become a member of the local Maker Space where they have all the tools I could imaging. They even have a CNC lathe where I could turn my cannons out of metal rod. I look forward to many long hours in that workshop building a multitude of different projects.

Edited February 2, 2018 by fnkershner

[Tim Murphy]

I came across this topic on Chuck's Medway Boat build.

I am not a computer adept person. Being 68 years old 

it is very hard to understand this stuff!

 

Your topic here has given me a chance to understand how

this is done. Thank you! Tim Murphy

[thibaultron]

Your welcome!