Drawing Precisely

comments (0) October 9th, 2011 in blogs

Killenwood Tim Killen, contributor
thumbs up 3 users recommend


In Chapter 12 of my book, I show the modeling for a Shaker Step Stool. A reader sent me a note with an attached SketchUp file showing the step stool at Step 8, page 82. At this stage of the drawing process, the Stretcher is complete with the half-dovetail at each end. The reader was having trouble pushing out the waste matching dovetail in the Side component. Here is the drawing as sent…..

 

Step 8 in the book says to open the Side component for editing and with the Line Tool, trace over the angled line at the bottom of the dovetail. This operation is shown below. Unfortunately, the line was not placed precisely at the correct endpoints.

Note the flag or labeled tag that SketchUp displays when placing the line - "Endpoint Outside Active". This is an important indication of a problem, but sometimes not recognized.

 

Although the line "looked" good, it was not good enough and when trying to push out the waste material with the Push/Pull Tool, the entire front edge of the Side highlighted as shown below. Therefore, the matching dovetail waste could not be removed.

 

So what happened here, and how do you find the problem? This is when you should put on your glasses and begin a close-up inspection, zooming in very close and orbiting around the problem. Here you can quickly see what happened. The Stretcher was installed so that its front face was not flush with the Side, leaving a very small offset. When placing the line, SketchUp grabbed onto the endpoint on the Stretcher not on the Side. (There was an indication of this earlier when placing the line - the flag and label telling you that the Endpoint was Outside Active.)

 

Often when I'm doing an inspection, I will make a copy of the component and pull it away from the assembly.


Since close inspection is critical with the Zoom Tool, you may need to change the camera's Field of View. Often, you can experience "clipping" of the view as you zoom closely. Changing the Field of View to 3 degrees, rather than the default 35 degrees, solves that problem.

Here is the angled traced line that was placed earlier on the front edge of the Side. Note the failure of the line to intersect with the left edge. Here is the problem and it is quite evident under close inspection.

 

To place this line properly requires zooming in closely. Below the Line Tool shows that it is connecting to the wrong endpoint (Point Outside Active). Again the flags will help.

 

Now I'm connecting to the right endpoint.

 

And here is the proper endpoint at the other end of the line. This line will now allow the removal of the waste material.

 

Often I catch new students trying to draw in SketchUp with the model zoomed way out, and getting very poor results. Once students get on to zooming with the mouse scroll wheel, they have much better success.

Tim
http://killenwood.com



posted in: blogs


Comments (0)

You must be logged in to post comments. Log in.

Advertise here for as little as $50. Learn how

Save up to 51% on Fine Woodworking

 

Become a Better Woodworker

About Design. Click. Build.

Learn the art and science of designing furniture in SketchUp with Fine Woodworking's official blog. Moderated by a devoted community of woodworkers, we feature step-by-step SketchUp tutorials on designing components, downloads of pre-built 3D models of furniture parts, and news and information about the evolving world of digital furniture design.

Buy the Video
Don't miss Dave Richard's brand-new DVD/video download, The Basics.

Buy the Book
Get Tim Killen's popular eBook, the Google SketchUp Guide for Woodworkers.

Basic SketchUp Tutorials 
Learn the basics of building furniture in SketchUp with these classic posts from the Design. Click. Build. blog.

Creating a Project Plan in SketchUp
How I Draw in SketchUp
Axes in SketchUp
The SketchUp Move Tool
The SketchUp Rotate Tool
The SketchUp Scale Tool

Materials, Colors, and Textures
Applying Wood Grain Skins in SketchUp

Easy Dovetail Joints in SketchUp

Digital Project Plans


Download and modify SketchUp files for select projects from Fine Woodworking. View all.

Top Sellers:
Matt's Monster Workbench
New England Pine Cupboard
Garden Bench

Meet the Authors

DaveRichards

DaveRichards

I am a Biomedical Equipment Technician. I maintain anesthesia and respiratory equipment for the largest medical facility in southeast Minnesota. I...
view profile
Killenwood

Tim Killen

I am retired from Bechtel Corporation after 36 years in Engineering and IT management. I grew up among woodworking machinery in...
view profile
FineWoodworkingEditors

FineWoodworkingEditors

...
view profile