Blades do wear out.
Aluninum, brass, copper, plastics are all soft and the blade can be run fairly fast.
Steel, sst are harder and the blade must be run much slower.
Also on thinner materials make sure that there is at least 2 teeth making contact on the cut or more teeth per inch on thin materials but you can run coarser teeth on thicker material.
I cut everything except hardened steel on my band saw, adjust speed and make sure I do not cut thin material with a skip/coarse blade.
Bud
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