Why do models have black edges

Why do models have black edges scale from 1 to 0.3

this is mycode


It seems your codepen is broken. Here is a working live example:


The black borders are semi-transparent artifacts. You can avoid them by

a) modifying your texture or
b) by using alphaTest instead of setting transparent to true.

Updated fiddle: https://jsfiddle.net/ckb7vfuw/

thank very much