Instructions For Making Sharpness Tester.
First thing i want to say is, this will only give you a gauge of your blades sharpness, it is not a tuned tester such as the Bess Tester. From the testing i have done, it is will give a fairly good indication of your blades sharpness though, it can help you improve your sharpening by giving you a number to go by. It can also help detect very fine burrs and wire edges. If you have sharpened a knife and you think it is really sharp but when tested gives an abnormally high reading, good chance it has burr/wire edge. There is a very good Youtube clip by Stroppy Stuff called Why Your Knife Isn't Sharp Even After Sharpening. I cannot do links, but i highly recommend you watch this, there is a very good tip with a small torch on detecting a minute burr and how to remove it.
So, first thing you will need is a set of small scales, i bought mine on Ebay for $20 delivered but you will have to access your own. There are 2 types, the cheap one that i purchased which will only give you a reading but not record it, the better quality ones record the weight, these would be the better option, but that is up to you. But try and get a set with roughly a 4 by 4 inch weighing plate to spread the weight.
You will need a testing medium, the recommended one is fishing line, it is supposedly more accurate, but is a pain to attach because it is so fine. So i went on the hunt and found some 1 strand paracord on Ali-Express. I got the multi-coloured to make it easier to see, work with and attach, and it works a dream, so much easier to work with. I would suggest getting both, then if you ever want a more accurate reading use the fishing line, or just get some single strand para-cord. But see if you can get the multi-coloured. If you want me to i can give the place where i bought mine from.
You can see the diameters of the 2 different mediums i use here, the fishing line is much finer so i suspect would give a more accurate reading, but the para-cord works well too. I tested both with brand new razor blade out of the wrapping. On the fishing line was 20 grams, with the para-cord was 38 grams. According to the Bess tester chart, a new razor blade should be 50 grams or under. So that was my original guide to see if this was close to being accurate. I think it is.
The last thing you will need is a base to hold the testing medium. This was easy to make, i used balsa wood simply because i had some lying around. I think the lighter you can make the base, the more accurate the reading may be, but that is only my opinion. Smarter minds than me may have a more informed opinion.
All i did was cut a square piece of balsa, cut 2 equal length arms and glued them upright to the square base. i Then drilled a hole through the uprights close to the top and put a small bolt through, screwed it tight with a nut, the put another nut on to tighten up when you wrap the testing medium around the bolt hard up against the first tightening nut. I scored a line across each upright just so the line sits in without moving. This only has to be a shallow score, i did it with a small hacksaw i have.
The one thing about the base is, it has to be all square, so the beauty of balsa is, it is so easy to work with, and you can sand it easily if your cut is a bit off.
This is the score line across the top of the uprights, does not have to be deep, it is just a guide to hold the line in place.
This is the testing medium screwed into place. One thing most important though is, it has to be tight, any slack and it won't work. It takes a bit of practice, but once you work it out is a breeze.
Hope this helps anyone interested, if you have any questions just ask, and if you have some ideas for improving this please post them. There are some very bright minds here who may have some good ideas about this.
Have a good one.