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Thread: How do you guys get Aldi chisels to hold up?

  1. #151
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    Presing and sintering, primarily multi-level parts made from carbong steel, nikel steel and copper infiltrated. About 70% of our parts go into new cars. If you have bought a new car in recent years, you have parts in it we have made. If you drive a F150, in the tailgate, there are 8 parts we make, for the torsion bar system.

    My gut feeling, as I have said, is the steel is basically re-melted, imported from wherever, scrap that could have anything in it., hence the variability, with some superb and others, bleh!
    If the thunder don't get you, the lightning will.

  2. #152
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    Quote Originally Posted by John C Cox View Post
    I did a quick bit of math on the Aldi chisels... I have no idea how they can make anything to a spec for that price.
    $7/4 = $1.25/chisel retail price.
    Was in Walmart a month ago to get clothesline. Cost a dollar. More clothespins than I am ever likely to need were three dollars. Picked up a pair of cheap ($.98) flip-flops. Can’t send a letter to China for a dollar, but somehow the market figured out how to not only get flip flops made, but here for less than that.

    Called capitalism.

    Good essay out there called “I, Pencil.” All about the incredible complexity involved in making something as deceptively simple as a pencil and how it happens without central planning, direction, or a single mind who can understand all of the individual skills involved. Modern (shorter and more readable) update on many of the same basic ideas laid out in Wealth of Nations.

  3. #153
    Quote Originally Posted by James Pallas View Post
    John, it would be interesting for you to say what conclusions you can draw from the weight of shavings. I can follow distances planed and thickness of shavings. You could in fact take three shavings and get the same weight as fifty shavings. The iron or blade would be cutting through the same length of glue (you said you used plywood) with each stroke for instance. Please help me understand what conclusions you can draw based on weight of shaving.
    Jim
    Here's some nice bedtime reading.
    https://www.srs.fs.usda.gov/pubs/rp/rp_so146.pdf

    It says that the cutting force increases more or less linear with the chip thickness.. So assuming typical friction - the friction wear would be proportional to the chip thickness assuming the chip thicknesses aren't too far out of bounds. At that point - you start splitting out the wood rather than slicing.

    But it's pretty tough to actually push cut too-thick end grain shavings in plywood.... The cut just stops because of the alternating grain layers...

    I suppose you could try it and see how it goes... For example - can you shave off 2x as much wood with a chisel (assuming a similar sharpening/edge prep starting from a freshly honed and deburred edge) by increasing or decreasing the chip thickness assuming you control the cut so it's not splitting or tearing out...

    My own experience with hand planes is that you really mostly save time because of taking 10x or 20x fewer shavings when you take nice thick shavings rather than whisper thin ones... You still need to resharpen at the end.
    Last edited by John C Cox; 06-14-2018 at 9:07 AM.

  4. #154
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    I do not know where people get the idea that remelted steel has bad properties and variability. Steel is a very recycled product and a lot of it is made from scrap melted in an electric arc furnace. Steel is carefully tested to meet chemical requirements and composition adjusted. If there is high variability it is because of poor quality control and not because it was remelted. Many parts of cars such as springs, gears, axles and lots of other parts are made from scrap melted in an electric arc furnace.

  5. #155
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    I'm not sure anyone alluded "bad properties", but rather variability. It's not poor quality control, but more of limited or no quality control. There are some elements that can be problematic to the end recycled product, such as silicon, phosporus and a host of others that can contirbute to less than desireable results, such as the product being prone to corrosion or worse.
    If the thunder don't get you, the lightning will.

  6. #156
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    I guess my metallurgy and steelmaking is different. In an electric arc furnace the silicon is oxidized out during the process and is essentially zero when you are ready to tap the heat. Phosphorus is not usually a problem because most scrap has fairly low levels. The exceptions are with grades made for machining and some other special grades.

    Uncertain about the corrosion comment and what elements make it more prone to corrosion. Yes, you can add elements like chrome and nickel to make steel more corrosion resistant.

    I made steel for a lot of years and there is always some mis-information going around about steel, how it is made and properties.

  7. #157
    I would think that remelting the steel would make it too expensive.

    It would make a lot more sense to me if I found out that they were made from forged drops or seconds out of somebody's chisel making process.... Often as not - there are plenty of drops from setups or whatever other hiccup that comes along... Parts falling out of the machine, too many made for an order, training a new operator, or whatever... And having a secondary market for stuff that's not necessarily 1st quality is a good thing. It helps recoup some of the sunk cost.... And then the stuff gets sold somewhere rather than being carted out in a dump bin to be remelted....

    I also noted that these were sort of odd size for metric... For example 8mm instead of 6mm.. 18mm instead of 19mm, etc.. Perhaps that's the sizes you get if you want the boo-boo's ground off - so grind down a 12mm to 8mm and viola - dings and bad grind marks are gone....

    Branded 1st quality China made chisels runs 10x the price (retail). No doubt there's more in those markup - but still....

  8. #158
    Larry,

    Good to see you commenting on this thread. I always wondered, how do they "purify" the scrap metal? Say, you want a high carbon steel with hardly any alloys, how do you get rid of chromium, vanadium etc that is inevitable in scrap? Or are those concentrations in the usual scrap steel very low anyway?

  9. #159
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    In my business (powder metallurgy), scrap is handled multiple ways: melted/atomized, then additional elements added for certain properties, or melted/atomized as is, or pulverized, sieved & reused and pulverized, sieved with additional elements added. From people I know in the steel industry (was actually out with two last evening, that produce and supply wrought material and not powder metal), the Pacific Rim uses similar methods to America, with the end result directly correlated with the quality desired in the end product, which correlates with the accepted quality level ($$$) of the purchaser of the resulting steel.

    To John, steel is melted, used, scrapped, re-melted many, many times.
    If the thunder don't get you, the lightning will.

  10. #160
    Yeah, adding alloys ain't too difficult, but removing them! I googled a bit and it seems they have some processes to remove valuable alloys, but mostly because those are very valuable and not to make pure iron. i doubt there is much market for pure iron these days.

  11. #161
    Kees.

    I am sure it's possible to purify recycled steel to get something along the lines of Hitachi White. It may be easier though to start off with good quality clean ore... If you look - W1 is basically that with a bit higher allowance for P or S... No doubt some of the proprietary versions of W1 would qualify as "high purity high carbon steel"...

    The thing is demand... The demand for tool steels seems to be more in alloyed steels that are far more forgiving in high volume industrial processes fed by unskilled labor.. So for example - adding a pinch of V or Cr or whatever to help retain a finer grain structure, a more forgiving window for heat treatment, dimensional changes, easier manufacturability of parts, or whatever...

  12. #162
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    Where is Patrick when we need him so much? This topic is right in his wheelhouse.

  13. #163
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    Maybe he went with Gilligan, on a three hour Tour.....
    first mortise.jpg
    Still using mine.....

  14. #164
    Larry is (or was) an actual professional metallurgist... I believe Patrick is a software developer...

    I was hoping we could goad Larry into offering up some opinion on what is going on with these chisels... But so far he has resisted strongly....
    Last edited by John C Cox; 06-15-2018 at 3:21 PM.

  15. #165
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    My resistance is actually a lack of information available. If we knew the chemistry and microstructure, we could make informed comments. Without a good lab investigation, it is just conjecture or guess as to what is going on.

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