Latest Discussions : Tools & Workshop


03:44AM | 06/03/05
Member Since: 05/23/05
24 lifetime posts
I'm going to make an octagon around a round column using crown moulding and want to know how to determine the angle to use on the mitre box. Let's just say for this example the column is 12" round.

I can somewhat figure out that it is probably half of a 45degree angle used for 90degree inside/outside mitres on 90degree walls, and making the same angled mitred cuts on both ends should get me the results i'm looking for.

Q#2: If it was previously done and one section needed to be replaced how are the mitres degrees,angles determined for the piece being replaced.

Is their a tool that will give me the angle?


03:59AM | 06/03/05
Member Since: 04/10/03
116 lifetime posts
360 degrees in a circle divided by 8 for your octagon is a 45 degree angle divided by 2 for your mitre cut is 22.5" on your saw. doesn't matter if its a 2" circle or a 22" circle. you just need to determine the length of your parts. I suggest drawing it out on paper first so your not cutting up your wood figuring it out

doug seibert

04:07AM | 06/03/05
Member Since: 08/10/02
842 lifetime posts

....Compound Miter or the Polygon.......


09:56AM | 06/03/05
Member Since: 06/23/04
161 lifetime posts
A common problem for first timers is laying the crown molding flat on its back when making the cut. This requires a compound angle saw and multiple angles.

Lay the crown molding against the saw fence at the same angle as it sets on the wall (or column). Clamp a strip of wood to the table to maintain that angle. When working with crown molding you must pretend that the saw fence is the wall and the table is the ceiling. The 22.5 degree cut is made without tilting the blade.



01:51PM | 06/04/05
Member Since: 05/23/05
24 lifetime posts
Thanks, yea some years ago i did cut a crown mould a few times before i figured out how to place in in the box, then it was

Thanks for the help.


06:29PM | 06/07/05
Member Since: 12/27/02
543 lifetime posts

You'll find a full tutorial on my site for installing crown.

Plus charts, a crown angle calculator, flat & in position step by step photos, all free.

The direct link is:

...any further questions use the dedicated crown molding forum onsite.

Alter Eagle Construction & Design


03:00AM | 06/10/05
Member Since: 04/10/03
116 lifetime posts
i'm sorry i misinformed you. I never saw the words crown moulding. i thought you were just replacing a piece of the column.


12:30PM | 01/04/22
octagon is 37.4 inches diameter, what are the length of the sides?

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