Thanks bunches for the info gang. This is exactly what I had in mind with a lot of the examples already given.
I'll start sorting and compiling and then hopefully be able to have a complete chart.
Currently I own .13mm, .16mm, .20mm in Kanthal-D and .16mm and .0236mm in Nichrome. I also have the .15mm Nichrome? that Imeo sent out. Arriving tomorrow I'll have some 32 ga (.008mm) Kanthal-A at 13.96 oHm/ft.
I created about a dozen
coils the other day using .0236mm Nichrome for the NR/wire and .20mm Kanthal-D for the R/wire. I've found that the measurements Imeo gave at the very beginning of iAtty, that is, 10cm for the NR/wire and 5cm for the R/wire to be the perfect measurements to use so that is the basis for all the figures I'm going to calculate. I use 1cm at each end of the R/wire to created the twisted connection. Also, the wires.uk site has their stuff listed in meters of course and we in the US use standard measurement so I decided to go metric(ish) with my calcs. Most likely the chart will have figures for both metric and standard. I would like to include calcs/info for mm, SWG, AWG, and Gauge.
Problem I see is that some places selling wire use the SWG system, some use AWG, and still others use gauge or mm. This is my prompt to do this project because some folks, me included, can get confused when trying to get that certain oHm range in a coil. I hope to answer the question of "What wire is the best to create a 1.5 oHm coil"?
I'm calling 39" a meter, and 5cm to be 2". Close enough for gov't work. So using these figures, the
coils that I made were in the range of 1.7-1.9 oHm. The math I used was: .20mm Nichrome is 34.4 oHm/m, so divided by 39 gives .88 oHms per inch so 2 inches (5cm) is a coil of 1.76 oHm.
I want
coils to come in at the 1.3-1.5 oHm range so I will be ordering some .212mm Nichrome from wires.uk and that should give me a coil of 1.57 oHm because .212mm Nichrome is at 30.6 oHm/m so 30.6 (oHm/m) / 39 (in) * 2 (in) =1.57 oHm.
If I used my .0236mm Nichrome as the R/wire I'd have to also get some .25mm wire to act as the NR/wire. However a .0236mm R/wire would give me a 1.27 oHm coil which is way too warm for me.
Even though I mention that I want to use metric in my calcs I also use standard as that piece is easier for my mind to comprehend.
The math could easily have been: .212mm Nichrome is at 30.6 oHm/m so 30.6 (oHm/m) / 100 (cm) * 5 (cm)=1.53 oHm. The difference here, .04 oHm, is because of the rounding I'm doing.
Sound OK to everyone?
Repent
