Barmaley's Aggregated Questions Thread

Discussion in 'Maintenance, Tinkering & Embellishment' started by Barmaley, Apr 21, 2020.

Tags:
  1. Dogdrawz

    Dogdrawz Gold Member Gold Member

    Aug 15, 2016
    I use Mothers Alum. polish only cuz I had it for my wheels & it works really good on a leather strop.
     
  2. Barmaley

    Barmaley

    130
    Dec 31, 2016
    If I use 0.125" blade what cutting angle should I do? Does it depend on steel as well?
     
  3. Barmaley

    Barmaley

    130
    Dec 31, 2016
    garry3 likes this.
  4. Ourorboros

    Ourorboros

    419
    Jan 23, 2017
    Yes, Damascus is only for the look and for sales talk. Shun's 63 layers or whatever don't really help.
    Way back when, from the Middle East and points west, they didn't know metallurgy. They didn't know how to really purify iron and add measured proportions of carbon. But they figured out that they could combine two steel that had complimentary strong and weak attributes and get something in the middle.
    But now we can just pick a good steel and do a good heat treatment.
    If you ever watch Forged in Fire, notice how a guy with just a few years of experience can use the steel they have around their shop and make a weapon in 5 days that passes all the tests. In the old days, a fair amount of swords shattered. Now a no name 'smith can make a katana that can split a .45ACP fired at its edge. A simple mono steel blade. Or make a scimitar (something actually made with Damascus steel back then) that crashed through bone and still keeps and edge.
     
  5. Contact cement or spray adhesive works well for attaching the denim to the wood.

    The white compound will yield a slightly more polished finish than the grey, but both will work well. Your choice, as to which you try first.

    Green compound works well with simpler carbon steels like 1095 or CV, and with low-alloy stainless steels like 420HC. For anything more wear-resistant, the aluminum oxide compounds (grey, white) will handle those better. For steels containing much vanadium carbide (S30V, etc), diamond or cbn compounds will handle those better than will the AlOx compounds.
     
    Barmaley likes this.
  6. Barmaley

    Barmaley

    130
    Dec 31, 2016
    I still have a scientific question: Is the a way I can tell if the blade was made of VG10 or not?
     
  7. Blues

    Blues Lapsed SuperMod / Cattle Knife Rustler Staff Member Super Mod

    Oct 2, 1998
    Yeah, send it to a metallurgist and spend a lot more money for the analysis than you paid for the blade.
     
  8. Barmaley

    Barmaley

    130
    Dec 31, 2016
    It is the only way?
     
  9. Barmaley

    Barmaley

    130
    Dec 31, 2016
    Can I use wood glue to attach leather to substrate making a leather strop? Do I use soft side of the leather up?
     
  10. Barmaley

    Barmaley

    130
    Dec 31, 2016
    Can I use a compound test: if a green compound does not work on an unknown knife its hardness is over 56(or 58?) RHS?
     
  11. Blues

    Blues Lapsed SuperMod / Cattle Knife Rustler Staff Member Super Mod

    Oct 2, 1998
    VG10 has the following chemical composition: VG-10 – Made up of Carbon: .95 – 1.05%, Vanadium: .10 - .30%, Chromium: 14.50 – 15.50%, Molybdenum: .90 – 1.20%, Cobalt: 1.30 – 1.50%, Manganese: .50%, Phosphorus: .03%

    You can either have it analyzed...or you can buy blades made of VG10 from reputable dealers or manufacturers that are known to work with the steel. There are several steels the composition of which vary very little from VG10. How would you propose to distinguish them?

    At some point you are going to have to trust someone. You won't get a kit from amazon that lets you take an eyedropper with some reagent or chemical which will turn pink and tell you the steel is VG10.
     
    MolokaiRider and Mr.Wizard like this.
  12. Has more to do with the steel's hard carbide content, and not the Rockwell hardness of the blade itself. Rockwell hardness doesn't account for or measure the hardness of the carbides within the makeup of the steel, but only the hardness of the 'matrix' steel (iron + carbon) itself.

    If it's just simple carbon steel with no hard carbides, like 1095, it could be hardened up into the 60s and the green compound would still work just fine, because the compound is still hard enough to cut the steel and there aren't any other hard carbides there. Low-alloy stainless like 420HC also doesn't have much hard carbide content, and green works with it as well.

    However, with steels containing much chromium carbide, tungsten carbide or vanadium carbide, the green compound is less hard than those carbides and would struggle with them. These would be steels like 440C, 154CM, D2, VG10, etc, and beyond.
     
    MolokaiRider likes this.
  13. Mr.Wizard

    Mr.Wizard

    Feb 28, 2015
    How else could it be done, unless there is some unique property of VG-10 steel that would let you apply a kind of litmus test?
     
  14. With leather, it's probably thick enough that the glue type doesn't matter too much. You don't want the glue leeching through to the surface. Wood glue will probably work. Or, even simpler, double-sided tape (like carpet tape) also works well, and is easy to do. With the tape, it's also removable, so you can remove and replace the leather if you need to. That would be impractical with something like wood glue.

    Which side of the leather you use, is dependent on the leather itself. Most would use the smooth side; but with some pieces of leather, if the sueded side is good enough (not rough, uneven or lumpy), it can be used too. With a lot of inexpensive cowhide leather though, the sueded side might be too rough or bumpy to work well.
     
  15. bgentry

    bgentry

    Aug 3, 2009
    Do you have a source for this claim? Amazon takes returns for sure. But they also sell "warehouse deals" which are opened items. Presumably a large number of these are returns. I don't think Amazon sells any returns as new. But I might be wrong, as I don't have a source. That's why I'm asking if you have proof, or if this is just something you suspect is happening.

    I had such a hard time with this when I was a kid. I wanted SOOOooo badly to get unbelievable deals on items with unbelievable claims (like X-Ray glasses for example). My parents tried to teach me "you get what you pay for", and "if it's too good to be true, it probably is." I think I finally got it after the 2nd or 3rd rip off item. I've been a firm believer ever since.

    Totally agreed. Why is Barmaley so interested in whether or not it's VG-10? It was $14. For an 8" knife with a nice looking handle that he says has an awesome edge and cuts well. That's the bargain of the week as far as I'm concerned.

    Brian.
     
  16. Blues

    Blues Lapsed SuperMod / Cattle Knife Rustler Staff Member Super Mod

    Oct 2, 1998
    [​IMG]

    "Yep, that's VG10 alright!"
     
    Danke42 likes this.
  17. Danke42

    Danke42

    Feb 10, 2015
    All you need is a handheld tester.

    You can get a starter one for $30-35000.00 US.

    Don't get a discount one from a place selling $14 "VG10" knives.

    X-ray fluorescence spectrometry works by emitting an X-ray photon beam that is incident upon the atoms of the sample being analyzed. The interaction of the primary X-ray beam with the sample’s atoms excites the sample’s atoms’ electrons, causing some electrons to be knocked out of their orbits; this leaves a vacancy and causes a temporary state of instability in the atom. In order to correct this instability, electrons from higher energy orbits replace the displaced electrons. An energy that is specific to atoms of each element is released when the higher energy electrons replace the ones displaced by the primary X-ray beam. The emission of unique energies by atoms of various elements allows an X-ray fluorescence spectrometer to determine which elements are present in any given sample; the number of energies of each type detected provides quantitative information.

    [​IMG] [​IMG]
     
    Blues likes this.
  18. Barmaley

    Barmaley

    130
    Dec 31, 2016
    I agree! Great idea!!! The trick is to find exactly there is that "some point" - LOL.
     
  19. Barmaley

    Barmaley

    130
    Dec 31, 2016
    I was thinking about indirect method or creative idea. I can give you an example from the area which I know a bit more than knives. LED lights can flicker which is very bad for your health. You may use light analyzer to get precise test for an LED lamp or you may use a kids spinner toy to check it to a degree. If you spin the toy under the light of the tested lamp and you see visible strips moving around at some moment of spinner loosing speed you get flickering for sure. You can not accurately predict frequency of flickering etc, but you know as a fact that it is there!

    I was thinking that may be using different paste of a strop you may find that the steel is softer than claimed 60-62 HRS, or some color test in an acid or something (I am not a chemist). I have not real need for that test, I am just curious, how come companies consistently claim things on Amazon which are very suspicious.

    At the same point I know that sometimes if something sound too good to be true it may still be true. I remember the about 6 year ago I was shopping for front rotor for my car and found on Amazon a good brand machined and drilled rotors for $9.99 a piece delivered, they had 4 in stock. I bought two thinking that something is fishy here. They came well packaged in retail box and they looked great. So I decided to buy two extra sets because of the price and to my surprise I found that precisely same rotors on Amazon were $139 a piece. I can not explain what did happen first time but it did work.

    If we want to return to the $14 knife I bought it just as a guinea pig for me to polish my sharpening skills. But I was surprises at the blade. It is the best blade to chop scallions and dill and many other things. I have hard time to dull it intentionally since so far it is my sharpest knife in the household LOL!
     
  20. Mr.Wizard

    Mr.Wizard

    Feb 28, 2015
    Of course 60 to 62 HRC is not unique to VG-10, but if that is all you want there are hardness testing files that can at least get a ballpark measurement that would let you know if it's actually ten points lower.
     
    Barmaley likes this.

Share This Page