Not only do I not have one of these, I've never *seen* one of these. At the very least can you tell use where you got it?
Anyway, put a scale on the bottom board. Put the follower on top of the scale. Screw down the bar all the way. Note the amount of weight.
Having said that, I've never once tried to measure the amount of weight I have on a cheese. You need enough weight and no more. The definitition of "enough" depends entirely on your make and no recipe can tell you what that is. All I can say is that most recipes wildly over press their cheeses anyway, so you will be better off ignoring those instructions in virtually every case.
For normal pressed cheeses, you initially want enough weight so that whey beads up on the outside of the mold, but doesn't run at all. If whey is running, then you are probably over pressing. Over pressing early will close the rind before the whey has drained. Whey will drain without any weight at all (make cheese curds to convince yourself of that). The reason for pressing is to close the rind, not to drain the whey. Normally most of the whey is drained after about 2 hours so that's the target for closing the rind.
Because cheeses are usually draining freely as soon as you put them into the mold, for the first 15 minutes you should not press them at all. Then flip and while doing so inspect the rind. For very dry curds, you will want a little bit of weight, but basically just until the whey beads up. Again, if it is draining freely without weight, then leave it. Flip again after 15 minutes and inspect it. Then do a 30 minutes and flip 3 times (total time 2 hours). Each time, adjusting the weight until you are just getting whey beading up, but not running. After 2 hours, if the rind isn't closed to your liking, then you can put on as much weight as you want. Basically put on enough so that the rind is closed before you need to salt it.
The real exception to this is cheddars which is already drained (and salted) before going into the mold. You need a *lot* of weight (up to 8 psi). Your press is unlikely to be able to generate enough pressure with those thumb screws to close a large cheddar (unless you have super strong fingers). You may need hundreds of pounds. When doing a cheddar, you probably to replace the thumb screws with real nuts and then use a heavy duty torc wrench to see if you have done enough weight. You probably don't want the springs at all in that case (they will definitely not be strong enough). I make *very* small cheddars, so I don't need much weight. Again, I've never found the need to measure the weight. I just look to see if the rind is closing and if it isn't I add more weight. Using a wrench, you can feel how much resistance you are getting and you can get used to it really quickly. I've never actually used a torc wrench because there really is no need to know how much force you are using.
The main reason to record weight is if you are making the same cheese over and over and over again with the same equipment and the same conditions. You can record weights and hire someone who doesn't know as much as you to make the cheese. If it's a cheese you have never made before, you will always do better to think about it than to blindly follow what someone else has done.
