Large Cutters - 2 brands, Glastar & Inland (Also a Fletcher, but not familiar with it)
Glastar has a 3 wheeled cutter head, Inland uses your Toyo cutter. Glastar cutter head better fixed in a vertical position. Using your Toyo cutter in the Inland model, be careful to maintain the cutter in a vertical position, but the quality of a Toyo cutter wheel is superior to the wheel on the Glastar cutter, plus more functions (marker or X-acto) on the Inland model. Easier to center the Inland model due to tripod base. The Inland model is cheaper than the Glastar model.
Size of Circle:
Glastar: 5" to 24", Inland: 5" to 26"
Small Cutter:
DiamondTech Lens Cutter
Size of Circle: 1/2" to 5"
More expensive than the larger models
Can only cut circles within 6" of edge of sheet of glass due to support arm. Can only use Pinwheel or Morton to break out circle.
Measuring the circle accurately:
Use the marking on the cutter arm to get close to the desired size, then set the cutter up on the outer edge of the glass sheet. Score a short length, about 1", on one side, then the same on the other side, which will give you the diameter of the circle about to be scored. Measure and adjust your cutter to get closer, and re-score, but not in the exact same place, move over 1" or so. Repeat until exact diameter is test-scored.
Scoring the Circle:
Set the cutter up on the glass where you want the circle to be scored. Make sure there is at least ½" to 1" on each side of the circle, and that the glass is large enough. Test rotate the circle cutter, make sure there are no obstructions that will stop the arc of the cutter once it is in motion scoring the glass. Start with the cutter at an 8 o'clock position, (for right handers, 4 o'clock for lefties), press down on the base with your non-dominate hand, grasp the cutter part with your other hand, and make the score in one smooth motion until you have gone all the way around.
Breaking out the Circle:
3 styles: Pinwheel, Flip & Break, or Morton Safety Break
Pinwheel:
Make 4 to 6 relief scores out at a shallow angle from the edge of the scored circle to the edge of the sheet. Start a run with running pliers in all the scores, break off and then use groziers to remove the triangular points left on the circle. Use the Aanraku Ultra-Fine grinder bit to smooth out any rough spots and ensure a clean fuse after.
Flip & Break:
Make sure there is only 1" of glass on the outer edge of the circle first. Then flip the sheet over and press down with the base of your palm on the corner of the glass, directly over the score. Lift up the glass sheet in the opposite corner until you hear and see the score run, (or crack), repeat at each corner. When the circle has been completely run, but is still inside the sheet, make relief scored directly out to the corners and break with running pliers.
Can also use Morton Safety Break to assist in running score line. This is easier to do with Cathedral glass than Opal, as you can see the run in the glass.
Morton Safety Break:
Place the red button part in the middle of a Morton Maxi or Mini board. Align any part of the scored circle directly across the top of the button. Press down gently with the Red Handle part, with it centered across the middle of the score. You should be able to feel the glass start to run along the score. Move the glass to a part of the score line that hasn’t separated, and repeat with the Red Handle. Repeat until the circle has been completely run. Make 4 relief scores from the corners directly to the circle. Break out with running pliers one at a time. After the second line is broken, that piece of glass will fall out so make sure you’re holding it.
Patty Gray Donut Border Break:
Check out http://www.system96.com/Pages/CircleDemo/Rim1.html
Ovals:
The only one is the Fletcher Circle/Oval Cutter. It is very expensive, but is the only option for ovals. Score and break out the same as a circle.