I've checked the weights of the spools at my distributor, and yes their scale is legal for trade. I've done this many times with different sized spools and compared it to the weight on the bathroom scale I bought, and they're exactly the same. That to me is quite accurate.
"As for weights and measures certifying a scale they are just going to laugh at you if you bring them a bathroom scale. Even if you are able to adjust it to display the correct weight it will never be repeatable and will change all over the place with temperature and movement."
Who says I'm planning to take this to weights and measures? Are you saying movement won't affect the more expensive scales? How about temperature or how level it is? Even if I bought an expensive legal for trade scale it would mean calibrating and leveling at each jobsite, otherwise the readings would be inaccurate.
My point is it's accurate enough for my purposes, and I don't think that one would benefit by purchasing a more expensive scale when you take into account movement, temperature, elevation and levelling.
One more note, the $500 wire meter that I chose not to purchase was also not legal for trade, probably because it's not 100% accurate.
