tongue weight

Okay, I have a question. What is the best way to place the scale and brick to weigh the R-Pod? I tried it using blocks to elevate the scale and wood platform on which I used angle iron to support my beam and placed it directly under the socket where the hitch ball goes. I've also seen it where people leave the scale on the ground and set the jack's foot down on the beam. Given that the foot is behind the hitch socket, there is probably a slight inaccuracy introduced by using the jack foot, but is it significant enough to make the weight too inaccurate to use?

Thanks. So, if I understand the formula right, as long as the weight at the jack foot is under the hitch weight limit, the actual weight is okay since the actual weight is a smidge less than the weight at the jack. Thanks. I'll take the easy way out and use the jack leg and keep the scale at ground level. 

Charlie.   (Using your method which I like) The weight you record on the scale is the actual tongue weight correct?  That being so, I don't know if my bathroom scale is meant to handle 300 + lbs or am I missing something here.  Here I am looking at something simple and trying to make it complicated.

Okay, I'm a bit confused. In your example above, the weight at the jack (P) was 300 lbs. The result of your formula (W) was 285 lbs. Did you mean the weight at the ball will be slightly less than at the jack?

Those scales are about twice the price I want to pay. I picked up a digital scale at my local Re-Store for a couple of bucks. Add to that a couple of bucks for materials, and I will use that for a whole lot less than the $137.95 and up price of the Sherline and other brand models.

I keep looking at my local for sale advertisements to see if I can pick up a used one, but no luck so far.