View Full Version : Sketchup users

John Coloccia
08-13-2010, 1:59 PM
So I decided to use Sketchup to model a guitar for the first time. Normally, I'll make prototypes, draw stuff out, and work out all my problems in my head (hopefully) or in prototypes 1, 2 and 3. This time, I spent 3 full days in Sketchup and worked out all my problems there (hopefully). I printed out full scale patterns and we'll see how it goes. When I printed the patterns, I also printed a 5" square witness to that I could measure that on paper to see what kind of distortion I'm getting.


I printed out at least 3 copies of everything. Usually, 1 was a bit messed up and distorted slightly, and the other 2 were well within acceptable margins. Anything that needs to be precise or to an exact dimension will be done precisely, not by following a pattern, so being off 1/128" or 1/64" is not a big deal. Some of the bad print outs were off by over 1/16". That's noticeable to the eye, so I use those copies for markup.

Sketchup is OK by itself for designing, say, a square box, but it comes to life with all of the free, Ruby plugin scripts. The Bezier curve plugin is a Godsend.

If you spend time learning how Sketchup likes to align parts to each other, you will save yourself a lot of headaches. For example, if you grab a part at a centerline, it's trivial to then "snap" it to another centerline on another part.

If you turn your various parts into components, you gain two things: First, when you join two parts, you won't join their faces....you can still move and modify them separately. The REAL power, IMHO, though is that when you change one, you change all copies of that part. So traditionally, when you make a body shape that is symmetrical, you will make half, and then flip it along a centerline. Nothing ever looks like you thought it would look once you see the whole thing, so you do a lot of iterations. A far better way is to enter something that's sorta close, turn it into a component, copy a paste that component, flip it and attach it to the original. Now, as you tweak one side, you're automagically tweaking both sides and you can see what you're doing in real-time. Talk about powerful.

Their guides are fantastic, especially with the Bezier tool. I can setup all of my guide lines and I can immediately see where the body shape is going in relation to the guides. I can nail my points precisely and easily.

I'm a Software Engineer by trade, so I can very quickly and easily write whatever Ruby scripts my heart desires to give me anything I wish.

Still, it's not a full blown cad program. I've fooled around with other CAD programs, Alibre in particular, and they are clearly far more powerful than Sketchup. Sketchup is Free, and to get a full blown version of Alibre is about $1100.

The Question: Does anyone see any reason in particular to switch to Alibre's CAD offering? I'm not a CAD jockey. I don't really know what I'm leaving on the table and I don't really have the time to spend weeks just studying what I'm giving up by using Sketchup. Maybe the full version of Sketchup includes enough additional functionality that I should go there instead? All I know is I don't think I'll ever design anything on paper or in the shop ever again. Doing it on the computer is orders of magnitude faster and cheaper! I'm sold :)

What do you guys think?

Mitchell Andrus
08-13-2010, 3:37 PM
Hard to argue with a program that lets you do this in about 5 minutes:

David G Baker
08-13-2010, 4:21 PM
I took drafting in college back before Auto Cad, etc. Later in life after the military I would draw my projects on a drafting board. I did this several times before I realized that if I did a rough sketch with dimensions it would be done in a few short minutes and my project could be done long before I would have had the precision drawing completed. I have Auto Cad and Auto Cad Lite, I tried to learn to use them but didn't have the patients to stay with the long learning curve so I still use rough sketches. I took a look at Sketch up and a few other drawing programs but like the Auto Cad experience I went back to sketches.