designing square tapered column

[Christopher Kanda]

How do I determine the angles of the sides of a square tapered column? I want to make a 4" high column similar to the arts and crafts style with mitered corners. Am i over-thinking how to do this? Any help or links would be appreciated. This is what I want to make

[Jason Strauss]

Christopher,

I just constructed tapered columns for my porches last summer (see pic).

First off, I hope you meant 4' (feet) and not 4" (inches). I couldn't imagine what on earth you would make 4 inch columns for, but hey, not my project.

Second, I would seriously reconsider the use of mitered joints, particularly if the columns will be installed outside. No matter how tight you can get them, they will open up eventually. I used butt joints with biscuits, glues, and screws. The transitions between the stone bases and the columns themselves are pressure treated.

I used Gary Katzs' method and found it to be very simple with great results.

http://www.garymkatz.com/TrimTechniques/tapered_columns.html

To answer your question more specifically, I think my columns ended up having a 4 or 5 degree taper. However, I didn't determine the degree and work from there. I determined the necessary height, and then the width of the base and width of the top (to whatever was pleasing to my eye) and went with that. Of course, you'll need to know the degree to cut trip pieces.

My columes are made of MDO (medium density overlay). You can pick this stuff up at Menards for about $50-55 a sheet. it's very nice to work with and takes paint very well. I calulated my columns to cost about $85 each vs. the $500 for pre-made.

Good luck!!

[Rob Wright]

I made a spreadsheet to do this for me:
143199

I hope this helps - Rob

[Prashun Patel]

That's a great little tool, Rob. Thanks!

[Rob Wright]

Shawn - your welcome. I did that after arguing with my father that a tapered stave for a 4 sided column is not 45degrees when ripping it on the table saw. He still doesn't believe me even after I did the math!

[Tony Perrone]

That is the bomb. I have been dreading making the two colums for the front of my house because the wife didn't like the two I made using butt joints and I just didn't feel like doing the math :)
Thank you

[Christopher Kanda]

Thanks for the spreadsheet. I just need to figure out how to make the cuts now.

[Don Whitten]

Wow, thanks for the spreadsheet. Just made life so much easier.