can't make a good handle for your razor? take just the razor part and call it "kamisori".
can't make a good knife blade lock mechanism? make a metal tab that people are supposed to hold with their thumb at all times and call it "higonokami".
can't make nails or screws? join pieces of wood with splinters and call it "ishitani".
can't make glue? fold paper so it just about holds its shape and call it "origami".
do you only have literal mud at your disposal? make a ball out of it and call it "dorodango".

remember kids, when a subpar thing is called a western name, it's frowned upon. but if the subpar thing is from japan, weebs will drool over it and buy it. simple as that.