SketchUp Rules For Making Changes

Robert Lang Stickley Build Alabama Woodworkers GuildThe biggest advantage of SketchUp (or any other CAD software) isn’t in making an initial plan. That takes a while no matter what method you use. But if you want to change something, or make new design that is similar to an existing one, SketchUp lets you do that very quickly. I’ll be building the smaller of the two bookcases in a few weeks for the Alabama Woodworkers Guild. The guild wants to see a good representation of how Craftsman furniture goes together, and someone in the audience will go home with this project.

The main event is Saturday and Sunday, April 9 & 10, 2016. On Friday evening I’ll be given a demonstration of using SketchUp as the ultimate planning and problem solving tool for woodworking. One of the things I plan on showing is how I modified a classic design (the Harvey Ellis designed Gus Stickley No. 700 Bookcase) that piece is in my book “Shop Drawings for Craftsman Furniture” and you can find large format printed plans for the No. 700 Bookcase at this link.

BamaBlog_02The design problem presented by this guild presentation is typical; we like the look of a certain piece, but we want it in a different size. Perhaps we also want to change a few of the details. One of the rules I follow when using SketchUp is this:

Don’t draw anything if it’s possible to copy and change something that already exists.

I happened to have an existing model of the No. 700 bookcase on hand. As a side note, I made that model by importing my original CAD drawings from my book into SketchUp, that saved time and ensured that the model would match the book drawings. There are tons of models available on the 3D Warehouse, so it’s always worth a search before you begin.

BamaBlog_03Another rule I follow in SketchUp is this:

Any part of the model that is a distinct piece of wood (or other material) in real life is a distinct component in SketchUp.

When that’s the case, you can copy parts, as seen in the image above and modify them to suit your new project. I copied the case side, bottom, face frame, rails and trim off in empty space in the model. I could also have copied the entire model and deleted parts I didn’t want to deal with in the early stages.

Because all my parts are components, extras exist in the Components window, and in the original model. The bunch of parts in the image at left determine the size of the remaining parts. Before I made any changes to the components I selected them, right-clicked to bring up the context menu and picked “Make Unique”. That prevents changes made to the unique components from showing up in the original model.

BamaBlog_04Because I’ve made a lot of SketchUp models, (and I’m always looking for the easy way out) I use some unorthodox methods for changing things. With a good understanding of how the geometry in a model behaves you can grab 20 shelf pin holes at once and slide them into a new position, neatly centered on a case side that is about to become shorter.

I also grabbed all of the geometry at the top of the case side (including a dovetail socket for a back rail) and moved it down to shorten the side. For the arched rails at the bottom of the case, I selected the shoulders and tenons on the ends, then used the Move tool to change the length of the rail.

If you want to read more about stretching parts that contain complex geometry, this blog post explains the process in detail.  My SketchUp books also discuss how to do this and it’s a popular part of my SketchUp classes.

BamaBlog_05In just a few minutes I was well on my way to modeling an alternate version of the original Stickley bookcase. In my presentation on April 8, 2016 I’ll walk through the process of changing the entire model. I will also show all the ways to extract information from the completed model; really useful drawings that I can print and take out to the shop.

Making a 3D model is essentially pretending to build it. When complete, that model contains complete information about the exact size and shape of each and every part. That’s valuable stuff to have on hand if you want to be efficient in the shop, or on stage in front of a group of woodworkers.


— Bob Lang


SketchUp Rules For Making Changes — 3 Comments

  1. I looked at sketchup a few years ago and honestly didn’t think much of it but now you’ve got me intrigued. I’m wondering is it at all possible to import .dwg files, is it possible to to use reference pictures to trace patterns and so forth. Even though Inventor Professional is the perfect bit of software for mechanical designs and furniture designs the learning curve is huge and at my age and time constraints is proving to be almost difficult to grasp. I think I will give sketchup a go and have a little play with it. If it works out happy days. Thanks Bob Linkedin proved to be useful for a change.

      • Thanks for the reply Bob, I can use AutoCad but can’t model in it only 3ds max but max is not designed for accurate technical modeling on the fly unless you import everything from autocad and you are happy with the dimensions and when is anyone happy with their first design so changing dimensions on the fly like dado location or making a 45 or any other deg angle is not something you can do in max accurately which prompted me to look at Inventor but I’ll try sketchup pro for 30 days and if it can do what I want it to do then happy days. I’m sure one can import sketchup files in max for rendering purposes as 3ds max has photo realistic rendering capabilities with real world lighting and so forth.