scroll measuring problem

[ornamental4766]

Hi guys, i've been doing wrought iron work for years with all kinds of scrolls, twistts and etc and when i measure a space for a scroll to fit in i usually take a piece of stiff wire and wrap it around a scroll jig of the size scroll i want to use and then do the same thing on the other end and then straighten the wire out and measure the length of the wire to determine the length of flat bar needed for that size scroll. My question is this, what is the best way to measure a space for the length of flat bar needed to do a scroll for that space end to end, in other words, lets say i have a space 19" tall and i need to put a scroll in that space thats going to stretch the entire 19" space, whats the best way to determine how much flat bar i need to do a scroll thats going to fill up that 19" tall space. I really would appreciate any help because i've been doing it the hard way for so long that its starting to get on my nerves. Thanks guys.

[Glenn]

Use solder, a fiberglass seamstress (sewing) measure, or other soft flexible material to measure the line of the scroll you want. Remember that this is the CENTER LINE of the metal used for the scroll.

Some will make both ends, measure and cut at the overlap (in a straight or non-decorative section) then forge weld them together. Others just get close then open or close the scroll to make it fit.

[SoCal Dave]

One option is to look at a California Blacksmith Association Education video's. Mark Aspery has 4 videos that go over making a grill with scrolls for a level III project. In one of the video's, he takes measurements from a drawing and calculates the length needed in stock. By transferring you project to a drawing, or having the drawing first, you could use that method and come pretty close to what you need. Go to: www.youtube.com/user/CBAeducation I'm not sure if this is what you need but it might help?

[harrismetalsmith]

I do it a similar way. I use electricians pull line, and bend over a full size chalk drawing. I start at the end of the scroll and work my way back to a center mark and then measure the other side. But I hold the end back for whatever portion that I think the material will elongate for the taper on the end. Not very scientific but after allot of practice it works well. Sometimes taking a few more minutes in the layout saves allot of frustration in the process. If it saves mistakes it is not necessarily the the long way.

The electrician pull line is a braided nylon string. It is springy and will hold a curved line for about 6" as you travel along. Its easier than wire because of the spring in it.!

[NeatGuy]

A very simple way that I have used is to draw, in your case, a 19" square on a piece of sheet metal and use an opaque projector to project the desired scroll. I move the projector forward or backward until the scroll fits into the square. Once the scroll fits the square then trace it with soapstone. Now you can use the tried and true method of using a wire etc to find the length. An opaque projector is handy for making full sized drawings I bought mine at a swap meet fro $10.

brad

[Glenn]

Sometimes you can get trapezoid and parallax problems with a projector.
This can also be used to your advantage.

[clinton]

Are you making a C scroll or an S scroll?
Check this thread from Brian Brazeal- with a C scroll you can use math to figure out sizes.
http://www.iforgeiron.com/topic/13205-scrolls-and-collars/

[macbruce]

Small chain works for me............

[Frank Turley]

At the 1976 ABANA conference, Tom Bredlow gave away about 10, homemade, sheet-brass wheel travelers to various members. I still have mine; it has a 12" circumference. He scribed the inch and half inch lines, because chiseling them would have ruined the shape. I have used this in calculating length. If you draw the square or rectangular module in which the scroll fits, you can take an oversized scroll jig and rotate it until it appears to become smaller and fits inside the module. Then make it even slightly smaller in order to make allowance for the thickness of the scroll material. Make a soapstone mark on the jig where the scroll is supposed to end, the last place it will be tangent to the tool. This will be approximate, but will get you in the ball park. You can put the scroll jig on the layout table and draw around the scroll, stopping at the soapstone mark. Travel your wheel around the drawn scroll, making an allowance for scroll material thickness. You will be traveling outside the soap line ½ the thickness of the scroll stock. Youl'll be on the "neutral axis," the medial line of the thickness. This may not be perfect, but will get you close.

You don't have a wheel traveler? The old forged travelers did not have inches marked on them. It's not necessary.
The simplest forged ones consisted of a flat circle, forge welded. A flat cross member spans the diameter and is forge welded either end to the circle. The handle can be hot split so that each "tine" goes to the center and is riveted there. It should be free wheeling. If frozen, take a red heat and start rotating the wheel. In using it, make a mark on the circumference, and just count the rotations and partial rotation. Take the tool to a plane surface and rotate the same number of turns; then measure. Or if you're feelin' froggy, rotate and count rotations on the scroll material itself and go to work.

http://www.turleyforge.com Granddaddy of Blacksmith Schools

[nhblacksmith]

If you have a full scale drawing, it's easy. If not, sketch out the design full scale on a bench or piece of sheet metal (even plywood works) with soapstone or other marker. Set a pair of dividers for 1" and just step off the center line of the scroll. It will be pretty accurate. For small scrolls, use 1/2" instead of 1" because of the smaller radii.

[Francis Trez Cole]

Here is what you need to draw out your scrolls This is a Fibonacci gauge this will help with drawing out your scroll for a desired space here is a video and pdf plans for the project It will make it easier I use a length of bailing wire to measure mine http://www.woodworkingformeremortals.com/2011/03/phi-and-golden-rectangle.html

[Old N Rusty]

If you are doing scroll work understanding the GOLDEN SECTION is very helpfull. See "The Golden Section" `natures greatest secret` by Scott Olsen ISBN 1 904263 47 x This little book explains it.

[brianbrazealblacksmith]

whoops I used brians account by accident

[Blakksmyth]

The way I was taught was to draw out your pattern to scale on a concrete floor or steel top bench.You can then use a tailors paper tape, string or wire to work out the length. These days I use a cad program and print out the template full size. The computer gives you the length of stock down to the last millimeter although you have to allow for draw down or upsetting depending on what type of scroll form your doing. We even made jigged up rectangular boxes using any light scrap at hand, so that we could form the scrolls and then try them out in the jig. Very handy when you have a lot of the same form.
Have fun.

RobK

[Frank Turley]

Just a couple of notes.

Well made, proportionate, legitimate scrolls have different ratios. They are not all based on the golden rectangle.

Getting the length from a drawing is one thing. Nobody mentioned how difficult it is to forge a scroll to look like the drawing. That's why I recommended taking an oversized scroll tool and rotating it till it fits the projected module, leaving a thickness allowance for the scroll stock.

Getting back to the original inquiry re 19", I do have a scroll tool that has a diameter larger than 19".

http://www.turleyforge.com