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Cutting a curve in cedar
Andrew 2/25/03 11:36 p.m.
I am not sure if this qualifies as finish carpentry, but I figured if anyone could help me you all could.
I am helping to build an arbor to display at a home and garden show. It includes a curve(arch) made out of full dimension 2X cedar. I will have to glue at least two 2X12 edge to edge to get the width I need. What is the best way to glue up the boards and what is the best way to layout the arc that I need. I know I have not been very detailed, but thanks in advance for your help.

Re: Cutting a curve in cedar
Gary W. 2/26/03 12:27 a.m.
Let me take a stab at this. Glue and clamp the boards with good carpenters glue like Franklin, Titebond, Elmers etc. After it dries scrape the dried glue and sand.
To cut the radius you could just find the radius and scribe it on the board and cut. However, I learned a new way about 6 months ago, this by far is the fastest and easiest, first find how high you want the radius and how long. Then find the center of the board and mark the desired height, drive a nail in as a guide. Next mark each end with a nail as well. Now find a scrap piece of lumber that is as long as the length of the radius, on the left side mark the height of your radius from the top down. Measure from that edge towards the middle, half the length of the radius or cord an mark this on the top edge. Scribe a line from one mark to the other. Cut that angle. At the middle mark make a notch to keep a pencil lead in place while you scribe the radius. Place this board with the pencil notch at the middle mark with the nail. The cut you made on the scrap will slide along the nails and the pencil will scribe the radius. Turn it over and do the other side of the radius, now just cut and sand.
Hope you can understand this, it’s a little wordy, but it does describe a very easy way to scribe a radius.
Gary W.

Re: Cutting a curve in cedar
Gary Katz 2/26/03 1:01 p.m.
Gary,
If it were anyone else, I'd say phooey, that idea sounds nuts and I'm not going to try and understand it...but seeing as how it's you--
Please try and explain this a little better? It sounds like something we need pictures for. If you can help me understand it and you can't draw or get pics, I will.
Thanks,
Gary

Re: Cutting a curve in cedar
Kelly 2/26/03 1:15 p.m.
I tried and tried, but I can't see it either, Gary.
CX

Re: Cutting a curve in cedar
Gary W. 2/26/03 5:39 p.m.
Trust me; it’s a real neat trick. Your right I need to get a picture of this so I can explain it better. When I was told, I didn't believe it either, but when I saw it in action I was a believer. One of the guys I work with told me about it, in fact he had to tell me two times before I got it.
I will draw something up tonight and post it when I can. If that don't clear it up I will take a camera to work and put it on film.
Gary W.

Re: Cutting a curve in cedar
GACC Dallas 2/26/03 6:40 p.m.
You should use a good exterior glue. I'd say either Plastic Resin or Titebond 2. West Systems would be best. I'd dowel, spline or biscut the joint.
Then I would make a pattern with with router and a swing arm out of 3/4" plywood. Lay that over the finish stock, draw it, and then rough cut out the shape to within 1/8" with a jig saw. Then I would tack the pattern back on the finished stock and take a router with a pattern bit and finish it out.
Make as many as you want, they will all be the same.
That's what I would do.
Ed. Williams

Re: Cutting a curve in cedar
Joe Fusco 2/26/03 8:37 p.m.
Gary W,
It’s great when you discover something new only to find out it’s been around for centuries ;-).
Gary K,
Take a look at the “model”, it’s crude, but it gets the point across.
Stick Jig

Re: Cutting a curve in cedar
Gary W. 2/26/03 9:34 p.m.
Yep, I knew somebody saw this done before.
Joe, I knew you had this hiding in your vault of tricks that you keep to your self ;-) Its one of those tricks of the trade that almost got lost forever.
Just think, I would pull my tape measure out 30 feet to scribe a 30 foot radius. What was I thinking ;-)
Gary W.

Re: Cutting a curve in cedar
Joe Fusco 2/26/03 9:55 p.m.
Gary,
About two years or so ago, there was a pretty good conversation on how to draw/layout big arcs on BreakTime. A lot of good ideas (and graphics ;-]) got tossed around then. This was just one of the solutions.
Joe.

Re: Cutting a curve in cedar
Andrew 2/26/03 9:56 p.m.
Thanks to everyone for helping. I will pick up the lumber tommorrow and see how I do. I think I will biscut, glue, and clamp. The visualization rally helped Gary. At first I thought you were crazy.
Andrew

Re: Cutting a curve in cedar
Gary W. 2/26/03 10:17 p.m.
Andrew, I knew my description was lacking, but I had to give it a shot.
Joe, what do you use to make up your graphics? I have something to animate GIF's that I use for my screen shots on my palm programs, but it doesn’t do things like yours.
Gary W.

Re: Cutting a curve in cedar
Gary Katz 2/27/03 12:26 a.m.
Wow. I feel like I have cottonmouth.
Maybe I watched that drawing a little too long.
Okay, Joe, you got me.
I'll go out in my shop tomorrow and see if I can figure it out.
From the moving drawing, it seemed to me that the circle top was actually an ellipse. Is that true? What were the notches for that Gary was talking about? I've never been able to draw a radius without a tramel arm. I'd really like to learn how to do this.
Gary

Re: Cutting a curve in cedar
Aaron Foster 2/27/03 2:09 a.m.
Joe or anyone - does the stick jig work with a router instead of a pencil?

Re: Cutting a curve in cedar
Derrell Day 2/27/03 6:56 a.m.
Mindboggling....where was I in math class?
Probably surfing. In the Gulf.

Re: Cutting a curve in cedar
Joe Fusco 2/27/03 9:11 a.m.
Gary W,
I use a bunch of different programs (I went for tool junky to software junky ;-])
I use Corel Draw the most to illustrate many of my Cad Drawings. I use Photoshop to edit photos and PhotoPanit to make the animations. I also have Fireworks and Illustrator, but don’t use them as often.
Gary K,
I said it was “crude” ;-). I really didn’t take the time to make it perfect. I just wanted to demonstrate the “movement” of the jig. When you make one you’ll see it works just fine.
Aaron,
My first impression was no and I started to type that, but then thinking a bit more about it, it might just be possible. You’d need to make a design change to make it safer to operate as it is there would be no support for the trammel points.
By the time I finished typing this I already have an idea and if I get sometime I’ll post it. Re: Cutting a curve in cedar
Joe Fusco 2/27/03 11:13 a.m.
Gary,
By no stretch of the imagination am I anything better then fair with any of these programs. I usual find the time just to “get them to do what I want them to do” and that’s it. So, take what I say with a grain of salt.
The first thing is that Illustrator is akin to Corel Draw and PhotoPaint is akin to Photoshop. The first are “vector” drawing tools and second bitmap drawing tools.
If you have Photoshop then you have ImageReady. That is the tool you want to use to make animated GIF’s.
I have and use Flash and Livemotion to make more complex animations, but I’ve found that for simple stuff the animate GIF works great. The file size is small and I can get my point across.
How I made this one was to first draw the main “scene/layer” in Corel Draw, you can use Illustrator. When I like it, I save it to a separate file like graphic_a.gif.
I then draw the next scene/layer showing some movement and then save that to a second separate file like graphic_b.gif. I do this until I completely show the movement I want. It can take as few as 5 separate file of as many as 20.
Then I go into PhotoPaint, and load the first file. There is a panel that says “Movie” on this it asks if I want to use the current document for the movie? I say yes and it creates the bases for the movie. The movie is actually an AVI file. I then add the “scenes” by load each separate file. Once their all loaded I save the movie to a GIF format and I done.

Re: Cutting a curve in cedar
Aaron Foster 2/27/03 12:29 p.m.
Joe - I was thinking about the router thing a bit more, and if the 'sticks' were stiff enough, you could run the router over the curve so the bit pulls the entire jig against the trammel points, which would need to be fairly secure. It might make sense to cut the angle in to a scrap of plywood and the bolt the router to the plywood. It would sure save some time and in theory be very accurate and clean on those large radius curves. Just a thought, anyway.

Re: Cutting a curve in cedar
clampman 2/27/03 2:16 p.m.
Aaron,
I cut my elipses (half an elipse that is) out of mdf with a makita plunge router without marking them first. I use a jig comprised of an extension of the centerline of the elipse as a guide for the elipse width peg to ride on. It takes two guys to do unless you get fancy and cut a dado in the centerline extension to capture the width peg. I make the first passes 1\8 th too big, then take one full depth final cut of 1\8 so the final deal is smooth.
I then use the mdf as a template for a pattern cutting bit to cut all the real elipses with.
Clampman

Re: Cutting a curve in cedar
Frank 2/27/03 4:51 p.m.
Look in the JLC CD 93 search Ellipses
Two article’s one on GaryW layout Feb.93
And Jig and router March 93.

Re: Cutting a curve in cedar
Gary W. 2/27/03 6:16 p.m.
Gary, their is only one notch and it is used to keep the pencil in place while you turn the jig.
Gary

Re: Cutting a curve in cedar
Derrell Day 2/28/03 6:09 a.m.
Joe,
Was your stick jig for an ellipse or a circle?
Like Gary, it looked mighty "ellippsey" to me.

Re: Cutting a curve in cedar
Joe Fusco 2/28/03 7:44 a.m.
Darrell,
LOL, like I said to Gary, I didn’t take much time to make it perfect. It does get a little “ellippsey” at the end there. . . ;-)

Re: Cutting a curve in cedar
Gary Katz 2/28/03 10:30 a.m.
Joe,
I wrote earlier but the board ate my message. Thanks so much for the drawing and the explanation. I didn't know what Imageready was for. I opened the image there and Wow, it looks very simple to do. I'll give it a try.
The nice thing about being naive is that there's so much to learn. I just wish I had more time...
Gary

Re: Cutting a curve in cedar
Andrew 2/28/03 4:31 p.m.
Thanks for everyones help. I new I could count of all of you to come up with an idea that would work. Time spent on these forums is priceless. I learn something new everyday.
Andrew

Re: Cutting a curve in cedar
Derrell Day 2/28/03 6:08 p.m.

That'll be $2.51

 
     
     
   
     
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