I'd like to start a thread here dedicated to providing "quasi" technical information regarding appropriate wire for foam cutting. There are several other wire threads but seem to lack in any discussions or info on comparisons of the physical properties of the various wire types available. We all want to use the best wire for our machines, but everyone seems to recommend a different wire or supplier.
To start off let me state what I believe the parameters for the ideal (best) wire are:
A - Resistance to breakage
B - Resistance to bending (bowing)
C - Uniform heating
D - Minimal current needs (high heat/current ratio)
E - Minimal stretching (elongation)
F - Modest tensioning force requirement
G - Availablity and reasonable cost
There seems to be two types of wire in use: Resistance and non-resistance (for lack of a better term) wires. Perhaps another appropriate terminology would be semi-conductor and conductor type.
Resistance wire (NiCr - Nickel/Chrome alloys) heats proportionately to the current (amperage) running through it and uses relatively low current. As most substances, it stretches (elongates) when heated and placed under tension. It is widely available in various gauges and alloy mixes.
The non-resistance wire that seems to be used by some here includes piano, guitar, leader, and other mostly steel alloy types. Correct me if I'm wrong but these require higher currents (dangerous and require more robust/expensive power supplies and VERY precise current control?), but offer an advantage over resistance wire in terms of higher strength, breakage resistance and minimal stretching.
I've always used NiCr wire for its availability and simple/low current requirements. It does seem prone to breakage however. In my mind, NiCr wire that rarely breaks would be ideal.
Feel free to post any corrections or additions to the preceeding
AND any wire technical specs/info or links to such info.
PLEASE NOTE: Please only post messages of technical or quasi-technical info regarding wire for foam cutting.