Parts: 3 (4 with extension) - high impact plastic

Instructions: Well-illustrated quick start guide, plus web site

Quality: 10 - durable and easy to use

MSRP: £11.95 GBP (~ $21.55 USD/$ 27.12 CAN/ € 17.22 EUR ) plus postage, available from Circle Scribe

Overall Rating: 10 - simple to use, rugged and effective - well worth the asking price.

One of the more difficult scratchbuilding techniques for me has been cutting circles and arcs. I've tried all the standard methods - templates, chucking a scriber in a drafting compass, even the circle cutters you can get at craft stores. All have their drawbacks - especially the circle cutters I've used, all of which were designed for paper and choked on styrene. So, I was quite interested when Bill Harper at Circle Scribe introduced me to his company's flagship product.

What You Get

The basic system includes the scribing disk, a packet of № 10 surgical blades, two blade holders for thick and thin materials, a mechanical pencil, a ruler and a single A4 “Quick Start Sheet” showing you how to use the device to cut a perfect circle. The disk and blade holders are made of a sturdy clear plastic material. Additional items you can get include an extension piece for cutting larger circles, a blade holder for making bevelled cuts, and several booklets showing how to make different shapes and designs.

The smallest circle you can cut with this system is 5mm in radius; the largest with the basic system is 100mm radius (in inches that's roughly ½" - 8" diameter circles). The new extension piece doubles the maximum size to 16" diameter. The circle radiuses go up in increments of 1 mm so you can cut any whole number of millimeter radius between 5 and 100. The system is designed to use the toughest shapest blade in the UK - the Swann-Morton Size 10A Scalpel Blade. Bill reports one blade will last "a whole day cutting card constantly at exhibitions, or for the duration of a job when we're cutting tough acrylic plastics". The blades are easily replaceable and inexpensive - in the UK anyway (more on that in a moment).

In Action

I found the system quite easy to master. First you slide a blade into place in one of the two blade holders (which one you use depends on the thickness of material you're cutting). There are pegs on the bottom of the blade holder that fit into the holes in the disk. You put the blade through the appropriate hole, then slide the pegs in place. Locate the center of your circle and place the pin at the center of the disk there. I found it easiest if I used a scribing tool or compass point to poke a small hole at the center point to ensure the pin went in the right location. With one hand resting on the blade holder to keep it in place, use the other to turn the disk. You don't need to push down on the blade holder - in fact, that just makes things harder.

I tested the system on .030" styrene sheets from For Sale signs. I was able to quickly and cleanly cut out circles, half circles and arcs. I found that scribing the shape with the sharp edge of the blade first, then reversing the direction I was turning the disk so the back of the blade became the scribing edge helped prolong blade life. Actually, the blade seemed to work better after the tip had been dulled a bit. The extension was just as simple to use - just fit its slots into the appropriate holes on the disk, tape it in place, and locate your blade as before. This made short work of a shroud I've bee trying to make that is too big for any of the templates or compasses I have on hand. I also found that the tip of one of my engraving tools is just long and thin enough to fit through the guide holes. This will enable me to scribe arcs and circles larger than the templates I have available.

How does it compare to the circle-cutting tools you can find at craft stores? In my mind, there is no comparison. Every one I've used comes with a small blade that is prone to instant breakage when used on styrene. None have a positive alignment guide like the Circle Scribe's center pin. None will allow me to use any of my scribing/engraving tools. All have cost the same, or close to it.

The only drawback I can see to the Circle Scribe system is the use of the № 10 Swann-Morton scalpel blades. I have not been able to find similiar blades in the usual places around here, and the standard US № 11 blade for sure does not fit. However, a quick check online indicates several model supply retailers, including Micro-Mark, stock " № 10 surgical blades", which may work. When I brought this up with Bill, he said "I'm not sure about availability in the US ... but that wouldn't be a problem since they are so cheap to post." so it may be best just to source replacements from his company.

Editor's Note: I've since been informed that Cincinnati Surgical imports these #10A blades to the 'States. If all else fails, you can visit their website to order them in blocks of 100 blades.

Conclusions

I'm hooked. The Circle Scribe is a great addition to my scratchbuilding arsenal - easy to use, precise, and durable. The price is comparable to what you'll find in the stores - here in the US, anyway. It's well worth getting for anyone who has the need for doing what the system enables you to do.