3D Versus 2D Drafting
The pros and cons of three-dimensional CAD drawing versus working in two dimensions. June 26, 2006
Question
I'm about to take a 3-D ACad class, since I just finished the 2-D class. Just wondering how many of you know how to use it and if it has been very helpful.
Forum Responses
(CAD Forum)
From contributor C:
3D Autocad has been great for me. It takes time to learn, but working 3D can be much easier than 2D more times than not, if you know what you are doing.
From contributor M:
3D is the way to go - it is real engineering. Real objects. 2D is just a bunch of lines.
From contributor W:
2D is a bunch of lines? Isn't 2D drawing how everything in the history of the world was defined and manufactured up until less than 20 years ago? Perfect your 2D skills, as they are invaluable. Those lines and arcs are how every CNC machine tool moves. The world of X&Y will never die! Learn 3D as well, but do it in a real solid modeler like Autodesk's Inventor or Solid Works. Then when you have a fancy 3D model, try and figure out how you can machine it as easily as a 2D drawing.
From contributor K:
"Then when you have a fancy 3D model, try and figure out how you can machine it as easily as a 2D drawing."
I do. I've been programming NC code since version 12 of AutoCAD. Just a year ago we moved to 3D (in AutoCAD) and love it. We tried other software and even had over $40,000 tied up into one package to find out it was worthless. Now an easy 80% of all of our NC programming is fully automated through feature recognition.
From contributor S:
Solidworks and Inventor are good programs, but they are mechanical engineering programs, they are not programs that were created for woodworking. Both of these programs are also quite difficult to use, with a learning curve of many months, maybe even years, depending on how committed you are to learning them. This is of course the case with any software. If you don't spend the time to learn them, it will take you much longer, but to suggest that someone use either one of these programs to manufacture woodworking, in my opinion, is not a good suggestion.
From contributor J:
Been using Solidworks since '98. It has been invaluable on complex architectural pieces, cumbersome for institutional products (read plam casework/repetition). Learning curve is 1/10, no, dare say 1/100, that of Autocad. Software is a tool, and as the cliché goes, use the right tool for the right job. The more tools you have, typically the easier your job. However, it all comes down to lines on a flat piece of paper, and how you communicate (with the AIA or the shop floor/subcontractors) with that piece of paper, is what's important. As for mechanical engineering specific programs, the computer doesn't know or care if it's glass, steel, wood, granite or titanium, and for most CNC's, they could care less if they're cutting 2D entities or NURBS…
From contributor E:
I have found drawing with 3D solids in AutoCAD to be very helpful. It is clear to me that CAD in general is going in this direction. In fact, it is already here, alive and well in the woodworking industry (yes, I use Smartlister). The sooner you learn 3D, the better off you will be. It is interesting to note that at AutoDesk University in Orlando last week, a major part of the Key Note Presentation was about the coming shift to 3D in all the design and engineering disciplines. They predicted that 3D will be the dominant drawing practice in the near future. They compared the shift from 2D to 3D to the change us old timers went through when we switched from the drawing board to the computer. So I recommend you go for it and keep an open mind. It is not hard to see the potential of it, and once you start to get proficient, you will see it even more.
From contributor I:
In the Key Note, did they discuss the differences between Auto Cad 3D Solids and Inventor? Where did they see that going?
From contributor E:
I do not recall them making a distinction between Inventor and AutoCAD at the Key Note. As you know, AutoDesk makes many CAD products, and they were all represented at AU. Their focus was on 3D in general, regardless of specific products. I would think that this could also include products outside of AutoDesk, although I am sure they would prefer it be theirs. AU was not geared for woodworking specifically. In fact, I did not meet anyone else there that was in our industry. By the way, AU was awesome, and I recommend it highly.
I would like to point out that Inventor may have its place, but I personally do not feel that it works well with the custom woodworking that we do. I have heard others here saying that it works well, and they like it. That is great. Custom is a very broad term, so I will define it as we know it. One of a kind, period. If you take a close look at Inventor, you will see that it requires constraints. For the items we build, the time to apply these is just not efficient for us. Then there is editing, which we have to do on a major scale at times. Again, I cannot see Inventor working well for this. It could be partly that I did not know the program well enough, but that takes us to the issue of learning curve. I could see that Inventor would take some time to learn.
From contributor T:
Just a curious question to those that have become proficient with 3D. Do you find that the design lead time on your projects has become much longer as compared to the 2D layouts that you have done?
From contributor J:
A simple answer to your question is yes. The more complete answer is: from the 3D drawing I get a cutlist and parts ready to go to the CNC, and I do not create any more Escher drawings where the plan does not match the elevation, does not match the section... If I can design it in 3D, it works in the field, and there is no hand cutlisting, an operation that for me was prone to many errors.
From contributor P:
Ditto, especially the part about the Escher drawings. Because you are actually building the fixture, reception desk, etc. in the computer. If you can build with cabinets that are libraried and then just add in the custom parts, it saves some time.
From contributor M:
Contributor W, CNC is X Y and Z. Everything in this world is X Y and Z. Ability of some people to resemble shape of the object from three flat views (plan, Vsection, elevation) is exceptional. But almost everybody can see what object is if it is in isometric projection. Isometric projection has been around for centuries, before 3D modeling and computers came around. 2D is a bunch of the lines.
From contributor E:
Ditto, the design lead time can be longer. This is why I think it is harder to sell the basic idea of 3D. The mentality I have experienced is get drawings out for approval as quickly as possible, regardless of quality and accuracy and how something is really going to be built, with the premise that we will deal with that later. With 2D, that fine tuning of the engineering is often left up to the guys out in the shop who have to make it happen. With 3D it can sometimes take a little longer to produce those drawings, but in the end, they are much more accurate, and you get much more information from them than 2D, thus saving a lot of time overall. As mentioned earlier, you are building the product on the computer, not just showing a concept of what you want. This requires different skills than some are willing to achieve. This has been a source of much frustration for me in trying to prove the benefits of 3D. I am a firm believer of doing more work up front, and saving time in the long run.
From contributor K:
I personally can create new drawings faster in 3D than I can in 2D. Actually, must faster. Changes can sometimes take a little longer, however, our jobs are being milled within a few minutes of the customer signing off. There is no tooling to apply, cutsheets to create, BOM's to create, etc. It's all created for us.
From contributor T:
Thanks for the honest replies. As a designer myself, I found a problem with doing an initial design in 3D, mostly from not having all or exact information, but I still had to produce a preliminary drawing for the client, usually something quick. Then, as all the info and trades came together, I could make an accurate 3D model, but rarely have I seen a project that was perfect. To lay out a 3D drawing, the program is asking for exact info. I find a big conflict here.
But I see that making changes in a 3D format can eventually lead to very precise drawings and all the added benefits that come with it, so in the end I can see where the end product would be much better but for one-offs or custom. This longer lead time can cut into overall yearly drawing production numbers. How much more can you draw or how much more money can you generate with 3D? Did they discuss at the seminar that time is money? I think you get my point. With 3D I get great drawings, but how much more money can I make for myself and the company?
From contributor J:
If a job is already yours, you do the same thing regularly and you have all of your approvals. Obviously, quick production is the next step. However, if your drawings need to be approved by a non-architect or non-builder, the time you waste getting them to understand what you want to do can be great, with frequently two or three additional meetings per phase of production. With a 3D view, it's one meeting to see the concept and get the approval. Yes, time is money, but saving face is another. As I do mostly one of a kind items, it is embarrassing to go to a client once production is underway to admit that the sink won't fit, or I made some other conceptual error. (My employees have hung a picture of Sir Isacc Newton across from my desk to remind me to design things that can actually be built!) So yes, if you make stock items and deal only with builders and you have excel spreadsheets set up to quickly make cutlists, then 2D may be fine for you. For me, 3D is a must. I charge my clients more than my competitors, but the architect and homeowners are always impressed with my drawings, as they feel they look more professional.
From contributor P:
I think that most of the guys who use 3D are building store fixtures or really difficult to build monumental work. With store fixtures you can amortize the design time over many; consequently it is not as important on how much time you spend on the drawings. For one offs, I’m not sure 3D is worth the extra work. I have been using Solidworks since 98. Unless I’m doing store fixtures I generally don’t use Solidworks. That said, the days of doing a lot of repeats are over. So the more tricky stuff you can do quicker is definitely an advantage in the marketplace.
