Q: What's a good number of teeth in one sided thinning shears to avoid thinning the hair too much?
A: Actually, the number of teeth in the thinning shears is less important than the number of passes made through the hair.
When selecting general purpose thinning shears, select a pair that have fairly finely spaced teeth that are fairly slim. Remember when using them that you want to make one cut along the hair length between one-quarter of the way from the scalp and one-quarter of the way from the ends. If the hair is extra thick and long, you can make two cuts along the length at one-third of the length and the two-thirds mark.
The way to avoid over-thinning the hair is to make one pass at a time with the shears. Remember, you can always remove more hair, but once it's cut, it's cut.
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