I use a kitchen baking scale which can weigh upto 12.5lbs. Kitchen scales tend to accurate and have a nice sized bowl, large enough to balance the fuselage on. I also have a competition fishing scale (calibrated) which I can only use if I suspend the plane from its nose or tail; it is not practical for me as most planes I have have long 6ft or longer fuselages(I could stand on a chair or something). I find most use fishing scales of suitable sizes 0-15lbs, 10-25 lbs etc. The 50lb scale you saw (I wish I could catch that size of fish off the surf) is probaly not suitable for most planes in the 6-12 lb range.