Fitting chair rail to existing window trim

I know this isn't strictly a woodworking question but I thought someone might be able to answer this one.
I added a chair rail to a room with a window that has a existing stool and skirt. I'm placing the new chair rail to it matches the top line of the stool. The chair rail is a not quite as wide as the combination of the stool and skirt.
Seems easy right?
Now I already installed the chair rail around the other walls of the room. Everything is tight and looks nice. Only a few cuts to go or so I thought.
Wow, I tried using my profile gauge, made paper templates, made direct measurements and tried to duplicate the angles, tried holding up a piece of the scrap of chair rail with paper taped to create the profile I needed to make. (The paper templates always fit perfectly.)
I have nifty little scribe tools that work great when I'm scribing one flat object to another flat object. They weren't much help in this circumstance.
I have a scroll saw that I used to cut all kinds of test cuts. It seemed like the problem was that I couldn't draw the cut I need to make directly on the chair rail. I also tried taping paper down on the chair rail so it followed the same curves as the chair rail. Every time I tried to duplicate this cut it was always off. I just couldn't figure out what I was doing wrong. I tried breaking the cut in to different parts. I used different combinations of direct measurements and paper templates and my profile gauges.
(The profile gauge is the one with the little metal rods in it where you push it against the object you want to copy. The "negative" of the profile is copied from the opposite side of the gauge.) I even tried making the cut backwards on the flat side of the chair rail. (Thinking the curves were throwing me off from getting the correct measurements on the other side. Nope, that didn't work either.)
I spent hours making test cuts. I finally got something that worked but it was a fight all the way. I finally got it close and filled in the gaps with spackling compound and painted it. (I even called a molding shop where I buy trim and asked them if they knew a better way to do this. They didn't.)
Professional trim carpenters don't spend all day figuring this out. What do they do?
(Next time, I'll just move the chair rail up 3 inches and avoid the entire problem by placing a butt joint against the shutters that are right above the stool.)
Now that it is done, I still curious as to the best way to solve this or a similar problem.
Any thoughts?
Thanks.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
if I understand the situation right, I'd probably scribe the line with a pencil compass.
On Thu, 05 Feb 2004 03:04:16 GMT, "Carter"

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks for responding.
I tried that too. The metal point on my compass angled inward a pretty good bit. (So I couldn't put the point where I wanted to trace. I really wanted the point to be at a right angle.)
As I think of it now, I could have made a jig with holed drilled for a pencil in each end
(That way the pencil tracing the profile could have been inserted at a right angle.)
I wish I would have thought of it at the time.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Thu, 05 Feb 2004 04:06:37 GMT, "Carter"

sometimes I make special one-off tools for oddball scribes.one for that application might be a thin flat stick 2 or 3 inches wide, one end sharpened to a rounded point like a fence picket, with a hole near the middle that the pencil would press snugly into.     Bridger
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Thu, 05 Feb 2004 03:04:16 GMT, "Carter"

Not saying it's the best, but I might have removed the stool, appropriately notched it, and installed the rail behind it.
Another method, if possible, would have me slipping a piece of paper between the wall and the stool, tracing the profile, and using the paper as a template.
If I could see it, I might have other ideas, or simply use the same methods you did. <G>
Barry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks for your suggestions.
Your idea to remove the stool is one that I didn't consider. That's a good one.
Your other suggestion, about making a paper template - I tried that a number of times. The problem (at least for me) was when I made the template against the wall - it made an outline against the wall not the profile of the chair rail.
So when I tried to match the template that was drawn referencing a flat surface to the surface of the chair rail they wouldn't match up. (Because the total line distance of the paper template was shorter than the line that follows the contours of the chair rail.)
That's why the paper template always fit perfectly but it didn't give me a perfect cut when I transferred the line to the chair rail.
At least that is what I surmised when I kept cutting it and it was always off at least an 1/8".
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.