Hole Cutters are very useful Tools

Hole Cutters

Inspiration

I have a lot of types of hole cutters in my life - only some of them are suitable for cutting holes for hobby purposes.  When I cut a disc, I want to keep the part of the hole that is cut out and am not interested in how nice the hole that is left turns out.  I wanted to go over some hole cutters so that others could avoid wasting money trying different types.  The main problem with using hole cutters, however, is that the central drill bit will drill a hole in your material, but some of these can be adjusted to keep from having to use the drill bit as a pilot. Caution must be used if you are going to do so as the hole cutter could "travel", or move, across your material.

Materials

Here are the hole cutters I have used most recently. From the right, they are 1) Milwaukee thin wall hole cutter, 2) Vermont American hole cutter, 3) Bulldog hole cutter, 4) hole cutter of unknown make, and 5) Great Neck hole cutter. Numbers 1, 2, and 3 are recent purchases, while numbers 4 and 5 I have had for many years.  The key to a good hole cutter is more teeth per inch, or tpi, especially for harder, more brittle plastics.

Number 1 is a very good disc cutter, however, because of the thin wall, they are only made in "relatively smaller sizes - the one pictured is 1 3/8ths inches and was the largest one I could find at the local Home Depot.
Number 2 may be very good at cutting holes when you want a nice hole, but is horrible for cutting discs. This is primarily due to the very low tpi.
Number 3 is the most typical type of hole cutter I have owned.  It is nicely designed to get a nice hole, but not so nicely for the disc.  One reason is because the teeth alternately are bent inward and then outward, which causes a lot of waste for the materials you are using.
Number 4 is a very nice hole cutter even though having low tpi.  There are only three cutting blades on this hole cutter, but the nice thing about this hole cutter is that it is adjustable from 1" to 2 1/2".  I am sorry that there is no manufacturer markings on it, but I bought it about 20 years ago at a discount hardware store which no longer exists.  If storage or cost is a problem or it is important to have sizes that are not determined for you, then this is the hole cutter for you.
Number 5 is probably the best hole cutter I have if I want to keep the disc, which is my goal. The rings in front of the hole cutter are the blades and they fit into circular grooves of the piece that holds the blades.  I originally thought that this would be a very poor hole cutter, but it is probably as good, or better, than Number 1 (the Milwaukee).  The discs end up being very smooth and very round, and for storage, all of the blades can be inserted back into the holding device.