Autodesk Inventor for Woodworkers: Gottshall Block Part Modelling Exercise.
Some of those old Woodworking exercises you did way back when you were just starting out might be just what you need to help you learn Autodesk Inventor!
In his series, Robert takes a drawing from Franklin Gottshall’s Making Antique Furniture Reproductions (suggested by Mike Wenzloff) and takes us through the various steps of the exercise from marking out to the finished block.
Of course I couldn’t help but whip up my own version of the Gottshall block!
How to create a 3D model of a Gotshall Block with Autodesk Inventor
Here’s Franklin Gottshall’s original drawing above…
And here’s my version below…
(you’ll notice I have dimensioned it with dual units, and used modern English terms).
There are many different ways that this item could be modelled inside Inventor. Just to keep it interesting I’ve tried to use some of the less obvious methods.
The first Job is to add some Parameters. Notice that even though my template file is in Millimetres, I have added all the values in Inches.
Tip: Type ‘in’ or ‘inch’ after the value to let Inventor know what you want.
Inventor will convert the fractional inches into decimal inches and will even add up values with fractions that have different denominators (That saved me a lot of headaches, I can tell you).
Here’s my master sketch. I’ve tried to use the minimum amount of geometry – so it looks a little cryptic.
Next job is to create some Workplanes. I prefer to use work planes rather than working off other features. That way, if I need to edit a feature, I stand less chance of messing up any other features that were depending on it.
I’ve created one more sketch here for the concave cut. Note that I have made one end of the loop into centre line geometry.
Creating a Base Feature
Rather than extrude the base feature I thought I’d show this technique. First I use the ‘Surface’ option in the extrude command to create a work feature…
Then I thicken the work feature to create the solid. The whole solid is based on one single line of geometry. No loops = no loops to fail!
Creating Cut Features
I’ve used The various flavours of the Extrude tool to create the Cuts features.
In this case I’ve used the ‘From to’ option– Using the work planes I created earlier.
I have formed this cut using the ‘Distance’ option, which is set to the ‘Thickness’ parameter value.
Pow! a Cut through all!
Finally a ‘From To’ cut, using the faces of the original block itself (Usually a bad idea…)
The fillet with the ‘Fillet’ tool…
…And the Chamfer with the ‘Chamfer’ tool (No surprises there!)
I created the concave cut with the ‘Revolve’ tool – which is what I needed that closed loop with the center line geometry for.
For my final trick, I created the rebate on the end of the block with the ‘Lip’ tool from the new plastic parts tool set.
You probably won’t learn as much from my tutorial as you would from Roberts! I hope that I’ve thrown in a few unusual suggestions, why not leave a comment and tell me how you would do it.
You can download the Part file and a PDF of the drawing here:[Download not found]
If you are so exited about this article that you decide to download the Inventor file – Please leave a comment!
If you would like to find out how to turn your parts into assemblies – read Assembly Techniques for Wood workers.