The best-known non-impact printers are the inkjet printer, of which several makes of low-cost color printers are an example, and the laser printer. The inkjet sprays ink from an ink cartridge at very close range to the paper as it rolls by.
Here is an easy way to find your draw length, simply stand upright with your hands stretched out (hold naturally, do not hyperextend) and measure your arm span from fingertip to fingertip. Take this measurement in inches and divide by 2.5. This will give a good working draw length for your bow.
Many bow string material manufacturers will provide a chart on the product spool to tell you how many strands you'll need depending on the weight of your, so you won't have to make any of the calculations. Use a serving jig to keep the tension of the jig and strand materials while making your string. String your bow.