Turning

Subject:
my initial thoughts *PIC*

John K Jordan
I think tutorials and ideas for using Sketchup for woodturning design would be useful to people. I've used it to visualize turnings myself and to create illustrations for documentaion. I watched most of your video, skimming through some parts for now since I'm late getting out to feed the llamas. I tried to imagine the video from the perspective of a beginner, new or fairly new to Sketchup and modeling.

BTW, a bit of background: I did 3D modeling and graphics professionally for scientific and technical applications for the last 15 years until I retired, using high-end software, creating many technical videos as well, some for broadcast, some for congress, a lot for technical use, and some for promotion and pursuing research and development funding.

I do use Sketchup some these days and it is useful, although it does have some major limitations compared to the professional software, especially in two areas: booleans (subtractions, intersections etc.) and the ability to go back and modify elements earlier in the design process, for example, modifying an early curve, primitive, or boolean and having the entire finished model update automatically. Unfortunately Sketchup instead requires starting over at some intermediate step and redoing subsequent edits, awkward but usable.

Some initial comments about the video:

Keeping copies of many steps of an evolving design is a good way to work in Sketchup since editing an early entity is not always possible without rebuilding subsequent steps as mentioned. However, having them all on the screen at once can be distracting. I think the first thing the viewer should see is a finished 3D model of the goal, rotated in view, perhaps fading between the cross section drawing and the 3D rendering to give the feel of the inner and outer shapes, foot, etc.

(Using light and shadows on the initial model might help show the compound shape better and applying a wood texture/material could help grab and hold the attention of a casual viewer.)

One way is to make the finished object transparent or translucent material/texture and embed one half of the cross-section drawing inside the model. Or embed the cross-section in the model and hide/unhide the 3D model. You could start by rotating the view on the model in perspective view, then switch to a non-perspective front view to show the embedded drawing. All this is easier "in post" if editing the video instead of shooting it "live." I think showing the finished piece as the goal would be very helpful at the beginning before doing any drawing/editing.

After the initial into, I suggest showing the drawing and editing steps from scratch. Having all the intermediate steps already there and visible was a bit distracting. I do work the same way in Sketchup (due to it's limitations) but I like to move intermediate steps out of the way and hide them unless needed.

For example, I was confused at first at about 4:30 when you drew the two curves for the inside and outside of the bowl while the curves were already on the screen. It might be better in that step to show the finished curves as the goal, then erase or hide them and redraw the curves from scratch in the empty box, still showing the horizontal lines, tangents, etc.

I was confused again at 5:25 with "and I want to add a foot to this." The drawing on the screen showed an intermediate step of creating the foot which I assumed was the final shape of the foot. You showed making an arc on the existing profile but never showed how to create that profile from scratch, starting with the previous curves.

At 7:30 you describe shortening the foot a bit by drawing a line saying "that gives me this" but don't show or describe the actions/tools used to actually remove the excess. Of course, if the video assumes the view already understands how to do this operation it showing it is not as important. I do thing it is important to show drawing that step.

I think a video like this would benefit from two additional things:
- One, a bit about making and using construction lines. I use these constantly in Sketchup.
- Two, show how to use the measuring and dimensioning tools to pull useful dimensions from a diagram. For example, when I turn a lidded vessel, such as for a Beads of Courage box, I do careful drawings in advance to make sure I don't come up short in critical areas such as my taper-fitted lids and especially on wall thickness since I glue up a stack of hollowed rings of dry wood to turn the body. I draw full scale then take dimensions directly from the drawings with calipers. If doing this in Sketchup I would take the dimensions from the drawing. Simply showing the ways to get these dimensions from the drawing might be useful. (A recent thread by a long time Sketchup user was revealing when it was discovered he had someone overlooked the dimensioning capabilities of Sketchup!)

It's completely out of the scope of a video like this, but I suggest new Sketchup users spend some time becoming expert at using the inference snaps - they are amazing although a little quirky at times if you don't understand the details. It might be useful for your video to end with an on-screen list of resources for getting started with Sketchup, with a teaser about this at the beginning so people won't miss it.

Inference snaps, BTW, were built into Sketchup from the beginning with the first version by the original authors, At Last software. These authors were brilliant - unfortunately you only have to compare the very early versions with the latest versions to see how little the newest versions have evolved in basic functionality -so little has been changed the book I bought 13 years ago is still perfect for for learning the software. It's almost like the new owners don't fully understand and are afraid to touch the core of the software. However, they have added plenty of fluff, inter-connectivity, and some higher-level of functionality. Ok, off my soapbox.

I am thrilled to see you working on this. There are lots of resources for using Sketchup for flatwood and construction but I haven't seen a lot relative to woodturning, especially added to beginners. I hope this doesn't sound too critical - these are just my initial thoughts. When I get time I'll take a closer look and try to give it more thought if you are interested. I'd be glad to bounce ideas around.

Just for fun, here is one little Sketchup drawing I did to illustrate a cheap sharpening system Josh Bowman wrote:

JKJ

Messages In This Thread

SketchUp for Designing Turnings
my initial thoughts *PIC*
Re: SketchUp
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