I am always asked whether you can sew leather and belts with household sewing machines. It depends ;-)
To show where the limits are, how much you can expect a household sewing machine to do and what the differences are to a commercial sewing machine, I made a comparison video:
I test webbing in up to 6 layers, truck tarpaulin in up to 12 layers, fire hose in up to 3 layers and both soft, thin leather in up to 8 layers and firm and thick shoe leather in up to 4 layers.
I test all 5 materials respectively on a relatively recent Brother MS-6 domestic sewing machine, a 30 year old Veritas Famula Elektronik domestic sewing machine, an approximately 70 year old Pfaff 138-115U commercial sewing machine, and an Adler 69-373 leather sewing machine that is still being built that way today.
The sewing machine directory is one of the most comprehensive sites on the subject of old sewing machines: http://www.naehmaschinenverzeichnis.de.
Attention: Video is 48 minutes long ;-)
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