On 10/13/17 8:14 AM, ScottWW wrote:
"-MIKE-"Â* wrote in message news https://photos.app.goo.gl/DqXrs5DI2roJTli22

I need to replace the white board above this garage door. The 2x12 is
rotted out pretty bad. It will just fall out when poked with a
screwdriver or putty knife, so I'm going to replace with a new,
treated 2x12.Â* (Client wants cheapest option.)

What I need help with is figuring out how to transfer that arch to the
new 2x12. This isn't an arch that was drawn with a radius or trammels.
If this was a perfectly cut arch, I could just determine the radius by
bisecting the chords and extending perpendicular lines to find the
radius.

If you look closely, you will see that it's not even and the arch
"flattens out" near both ends. So I believe I'm left with trying to
transfer the exact line of the bottom of the soldier course of bricks
to the new 2x12.

Remember, the existing 2x12 will not come out in one piece or even
several pieces which could be reassembled to use to trace the "arch"
onto the new board. It's pretty much, mulch, held together with paint.

Any ideas?


It appears as though the 'mason' used a springy board to scribe/cut the
field bricks, then again to support the arch bricks. This shortcut
explains the straight ends.Â* The tightest curvature at the apex is the
result of the flexibility of the springy board and the amount of
pressure applied from below.


That was my thought as well for the same reasons you described.


I think the best way to match the arch will be to scribe vertically with
a large compass as suggested by other contributors.
Scott in Dunedin

That's leading the field in my head right now.


--

-MIKE-

"Playing is not something I do at night, it's my function in life"
--Elvin Jones (1927-2004)
--
www.mikedrums.com