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  1. #61
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    Quote Originally Posted by pmcgee View Post
    (Disston 240 median s/b 52)
    Interesting isn't it? The 240 looks like a very late product. The etch actually looks like it is printed on the surface of the blade.
    Innovations are those useful things that, by dint of chance, manage to survive the stupidity and destructive tendencies inherent in human nature.

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  3. #62
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    Quote Originally Posted by planemaker View Post
    Hi Rob. What does concern me greatly is that by not naming Maker 3 your unfairly clouding the reputation of other Boutique Saw Makers (including myself).

    Whats relevant is that you also making backsaws for sale. Now I personally believe its far from the case, but there may be other saw makers asking if your primary motive is more geared towards raising your own saw making profile.



    On the Sawmill Creek Forum where you also posted this data, you stated;

    Hi David,

    People are getting sued by companies here for writing negative comments on the Internet. See: http://www.forbes.com/sites/investop...eview-on-yelp/

    Speech is still free in America as long as nobody objects to what you have to say - that's why I have to be careful.

    As to Maker 3 and the results I got, who knows. Maybe it's a one-off problem. Maybe one lot of steel was unevenly hardened. As to Maker 3 and the results I got, who knows. Maybe it's a one-off problem. Maybe one lot of steel was unevenly hardened.

    While on this forum you are heading in a totally different direction by insinuating Maker 3 was aware his saw plate was below spec.

    My suggestion Rob would be to email a copy of your data to Maker 3 and note your concerns. My bet is Maker 3 will be in contact with his saw plate supplier asap.

    Nothing personal Rob.

    regards; Stewie.
    Hi Stewie,

    I posted the results to Sawmill Creek because 1) I'm angry that I've been taken advantage of and 2) I feel that the community needs to know that there's a potential problem.

    Maker 3's saw has other problems which I've detailed here on other threads suggesting that he or she knows what's going on with the product so contacting him/her would likely only lead to an angry response. Gappy inletting of the back to the handle and generally poor wood to metal fit, cosmetic problems with the metal work and poor performance relative to other custom makers. A saw made by another maker was recently sold on eBay that had obvious QC problems.

    Don't forget that Maker 2 is also making saws with plates that are softer than Disstons optimum 52 and nobody has commented on that set of measurements. What about Maker 4 with the exceptionally hard blades? I haven't (yet) heard any comments of "That just can't be, you're crazy/mean/insane".

    It seems my inquiry into this matter has divided the community into two groups, those that have chosen to attack me and those who thank me for my effort. I think that those who are on the attack may be motivated, at least in part, by a desire to not know what the facts are.

    The community's unquestioning acceptance of Disston's "52" benchmark is an illustration of this kind of willful ignorance in my opinion. Would it be possible that the number "52" Disston threw out might be a red herring designed to throw off the competition? Maybe the truth was closer to 54/55 as my measurements indicate. Rockwell tester's weren't even available until the 1920's meaning that Disston could only have known about the magical 52 for the last 30 years or so that the company was in business.

    As to the issues of liability, they're very real in America today. Might, in the form of money, makes right here and the link to the Forbes article above is an example. In your country I gather that there are pretty strong consumer protection laws in regard to 'fitness for use'. We don't effectively have such laws here. The laws are on the books but they are rarely if ever enforced. Thus, if you're a custom saw maker selling into the Australian market I think it would be advisable to test your raw materials to make sure that they truly are what you and your customers think they are. It's not very expensive or difficult. I've received a couple of private inquiries about the results and I've made offers to test questioned materials but notably nobody has taken me up on it yet.

    This is not the first time or field in which I have knowingly published results that are contrary to what a community might prefer and it's not the first time that I have taken flak for it either. Given the comments I've received regarding my other experiments I've done I'm beginning to think that there is a fraction of the community of saw aficionado's who strongly dislike innovation and refuse to question cherished myths. I strongly disagree with this approach to life.

    Here's an example of what may happen when we choose to be ignorant.
    Years ago as part of my work I became aware that a certain grocery store chain had a program in place to test all incoming fruits and vegetables for the presence of pesticides exceeding government specified limits. Laboratory staff would go to the warehouses of the chain early in the morning and pick up sample lots of all incoming produce. This operation ran 7 days a week and the sample collectors were in the field at 4 in the morning. The produce specimens were taken back to the laboratory, processed and analyzed. The results were reported back to the QA department at the grocery chain. While the samples were in testing all of the produce was quarantined on the trucks - nothing was unloaded until the results were in. Lots that were accepted were then unloaded and distributed. Rejected lots were, according to my information, taken to the warehouses of other grocery chains and sold.
    The end result of this was that the first grocery chain was ensuring that it's customers were not exposed to produce having illegal pesticide levels. Any and all of the other grocery chains in the region were therefore more likely to have produce on the shelves that did have excessive levels of pesticides.
    The chain doing the testing was thereby taking a good step in the interests of it's customers, but only it's customers get the benefit, everybody else gets the dregs. The chain never spoke of the testing it was doing so the general public had no knowledge of it's screening program. But what about the larger problem of contaminated and possibly unsafe produce being in circulation? Don't people have a right to know of such issues?

    If anybody who makes saws want's the results that I obtained in testing their saws only I'll tell them privately on the condition that they release me from all liability - in writing of course.

    Cheers,
    Rob
    Innovations are those useful things that, by dint of chance, manage to survive the stupidity and destructive tendencies inherent in human nature.

  4. #63
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    Hi Rob. In my opinion you could have approached this subject a little more tactfully. Most boutique saw makers IMO are doing an excellent job with the overall quality of their work.

    regards; Stewie

  5. #64
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    Quote Originally Posted by planemaker View Post
    Hi Rob. In my opinion you could have approached this subject a little more tactfully. Most boutique saw makers IMO are doing an excellent job with the overall quality of their work.

    regards; Stewie
    Stewie

    In the case of the saw in question it is very pretty, but the beauty fades on closer examination.
    This issue of saw plate hardness has taken on some of the characteristics of a religion - something that everybody accepts but that nobody is willing to question. Debating the relative merits of saw plate hardness in the absence of measurements is like debating how many fairies are dancing on a pin head.
    I spend my hard earned money on the saws I buy and I expect the best in craftsmanship, performance and materials.
    From my data it is clear that three of the four custom saw makers represented in my collection are not using 1095 steel. The numbers don't lie.
    If the problems with the Maker 3 saw are common to their other products then the truth will eventually out. If not then this saw is a unique problem and the boutique makers, users and collectors have no worries. Nonetheless my study points out the fact that improvement across the community is needed. Testing of raw materials is important and I see it as my duty to those I sell saws to.
    I use 1095, which I now know is somewhat softer than the average for Disston. However I seem to be alone in trying to advance the field.

    Cheers,
    Rob
    Innovations are those useful things that, by dint of chance, manage to survive the stupidity and destructive tendencies inherent in human nature.

  6. #65
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    To be clear, if there's anybody who would like to have their raw materials tested before being used to make a saw I'll do it at no cost and communicate the results confidentially to the requester. All you need do is mail me a flat piece about 2 cm on a side of the material in question. I won't test saws that you own from other makers because of liability issues. Send me a PM for my address.

    Cheers,
    Rob
    Innovations are those useful things that, by dint of chance, manage to survive the stupidity and destructive tendencies inherent in human nature.

  7. #66
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    Quote Originally Posted by hiroller View Post
    Interesting findings. Are you going to share the results with the saw makers?
    I think you should give the problem saw maker the feedback.
    The saw in question has some pretty obvious workmanship issues in my opinion suggesting, considered in light of the technical problem, at least QC issue and at worst a disregard for customer satisfaction. Defects obvious on casual visual examination should, for luxury items like boutique saws, be grounds for rejection of any particular item in my opinion.
    If the defects in the Maker 3 saw are willful or the result negligence then contacting them may provoke a bad response.
    Innovations are those useful things that, by dint of chance, manage to survive the stupidity and destructive tendencies inherent in human nature.

  8. #67
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    Rob, I think part of the issue is everyone is guessing or presuming who these saw makers are. Most of us are probably wrong. You have your reason for not declaring this which is fine. However if we were in the market for a saw we are now suspicious of all sawmakers but most likely none have access to test the saw prior to purchase. This is damaging the whole of a small industry rather than helping advance & improve it as your obviously passionate to do.
    He is an example. A bunch of thirsty people walk out of a desert and you put a table of glasses of water in front of them and say one glass is safe, most of them have a bit of poison and will make you very sick for months, but one will kill you. How many of those will want to drink? They will however want to know which will kill them, and which is water. They won't be happy knowing that you know & won't tell them, they are thirsty. All water is poison is the perception until more info is available.
    ..Live a Quiet Life & Work with your Hands

  9. #68
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    Quote Originally Posted by DSEL74 View Post
    Rob, I think part of the issue is everyone is guessing or presuming who these saw makers are. Most of us are probably wrong. You have your reason for not declaring this which is fine. However if we were in the market for a saw we are now suspicious of all sawmakers but most likely none have access to test the saw prior to purchase. This is damaging the whole of a small industry rather than helping advance & improve it as your obviously passionate to do.
    He is an example. A bunch of thirsty people walk out of a desert and you put a table of glasses of water in front of them and say one glass is safe, most of them have a bit of poison and will make you very sick for months, but one will kill you. How many of those will want to drink? They will however want to know which will kill them, and which is water. They won't be happy knowing that you know & won't tell them, they are thirsty. All water is poison is the perception until more info is available.
    Hi again DSEL,

    In principle I agree with your sentiments. However I have learned that creating, publishing or posting information that challenges broadly held ideas about reality is often hazardous. Wouldn't it be great if people were fair and objective? Unfortunately they're not. The bad saw in my collection may be a one-off, I don't know. I've always made it clear that this single saw has problems. I discovered the problems the moment I opened the box. The functional problem became clear the first time I used it. Being possessed of an inquiring mind I wanted to know what was wrong with the saw and now I think I've proved it, at least to my satisfaction.
    I posted this information over on Sawmill Creek despite a certain degree of trepidation because of things I have read about the users of that site. The majority of those who responded to my post decided to attack me as a person and dismissed my data. The reputation of that site is the primary reason that I post the vast majority of my hobby work on this site - Australians seem to be more open minded.
    As I wrote above, if you're worried about a saw you are thinking of buying ask the seller what type of steel they use. If the saw you receive doesn't meet your expectations then I think my work here may be helpful. In the alternative go out and get a tester. They're not that expensive and I'm finding mine to be extremely useful. Maybe something for the governing bodies of your Men's Sheds to think about if there are enough interested members.
    I think knowing is preferable to ignorance, even if the information is unpleasant.

    Cheers,
    Rob
    Innovations are those useful things that, by dint of chance, manage to survive the stupidity and destructive tendencies inherent in human nature.

  10. #69
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    I'd like to see some more extensive testing before making any firm conclusions - certainly before naming any manufacturer.
    If one of my students was doing this as an undergraduate material science project I'd say even though 5 measurements might satisfy a standard procedure I still think 5 test points per saw is on the slim side to demonstrate hardness is normally distributed, especially if normal stats are going to be applied.

    The first thing I would ask the student to do would be to demonstrate the method can generate a normal distribution on a reference material, both in several locations of the material and then using a reduced sampling regime across the surface of the material i.e. a hardness map. i.e. 20-30 measurements in a few locations and then 5 measurements at points event distributed across the material

    I would then ask the student to to the same (hardness map) of at least one saw using the same method..
    The surface finish issue can be addressed by sanding to the same level of smoothness.

    The other concern is that typical "consumer testing" issue of just testing "one" of anything can be problematic. I would suggest the student investigate at least 5 saws of the same make and model from at least one manufacturer. i.e. no map but at least 20 measurements per saw.

    To demonstrate "between sample" reproducibility I'd like to see the student repeatedly measuring the reference material between each different saw measurements to show there is nothing wrong with the apparatus or method. I'd also like to see one saw measured multiple times and in between revert to measuring the standard. A more representative value of the hardness would then be the external (or average of average values)

    Although this might be difficult for you to do to further increase the confidence of measurements I'd also ask the student to perform sone repeat tests using a different apparatus. Ultimately a completely independent set of measurements would be useful.

    I appreciate the time required to perform these measurements but I think even doing some of these it is one way to help reduce bias and hence criticism of the results

  11. #70
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    Hi Rob,

    I've been following your hardness testing with interest, I have some real concerns about the conclusions you are drawing. I also have some concerns about validity of measuring the hardness of thin plate.

    First off, Rockwell 60 is so hard that a file would skate off it... I get chisels hardened to 60-62 and there's no way that would be suitable material for saw plate. No I don't doubt that you are reading those numbers on your tester, what I know is that they can't be correct.

    Second, 1095 maximum surface hardness in the "as quenched state" is around 66 Rc, that is as hard as you can get... and at that hardness it's as brittle as all get out, spring temper is usually down around 50 Rc... If you have a saw that's 60 Rc, I bet the teeth will snap like crazy.

    Third, You seem to be suggesting that 30-40 Rc is too soft for saw plate... I disagree, I think it would be fine, while it wouldn't be my choice. Promoting the idea that the sawmaker is using sub standard material is a bit of a long bow to draw...

    My hardness tester is an Avery 6402 , while I think I'd have trouble measuring 20 thou plate hardness accurately I'd still be able to get relative readings to compare with some of your results.

    Ray

  12. #71
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    Quote Originally Posted by BobL View Post
    I'd like to see some more extensive testing before making any firm conclusions - certainly before naming any manufacturer.
    If one of my students was doing this as an undergraduate material science project I'd say even though 5 measurements might satisfy a standard procedure I still think 5 test points per saw is on the slim side to demonstrate hardness is normally distributed, especially if normal stats are going to be applied.

    The first thing I would ask the student to do would be to demonstrate the method can generate a normal distribution on a reference material, both in several locations of the material and then using a reduced sampling regime across the surface of the material i.e. a hardness map. i.e. 20-30 measurements in a few locations and then 5 measurements at points event distributed across the material

    I would then ask the student to to the same (hardness map) of at least one saw using the same method..
    The surface finish issue can be addressed by sanding to the same level of smoothness.

    The other concern is that typical "consumer testing" issue of just testing "one" of anything can be problematic. I would suggest the student investigate at least 5 saws of the same make and model from at least one manufacturer. i.e. no map but at least 20 measurements per saw.

    To demonstrate "between sample" reproducibility I'd like to see the student repeatedly measuring the reference material between each different saw measurements to show there is nothing wrong with the apparatus or method. I'd also like to see one saw measured multiple times and in between revert to measuring the standard. A more representative value of the hardness would then be the external (or average of average values)

    Although this might be difficult for you to do to further increase the confidence of measurements I'd also ask the student to perform sone repeat tests using a different apparatus. Ultimately a completely independent set of measurements would be useful.

    I appreciate the time required to perform these measurements but I think even doing some of these it is one way to help reduce bias and hence criticism of the results
    Hi Bob,

    I agree. I'm willing to make a controlled experiment on one of my saw plates, I don't really want to put prick marks all over a saw that I've paid hundreds of dollars for you know. Given the problems with thickness I propose to use a piece of 0.035" 1095 in it's as delivered state - no blue removal, and measure 25 or so test points with a distance between points of at least 5 mm. What do you think?

    Cheers,
    Rob
    Innovations are those useful things that, by dint of chance, manage to survive the stupidity and destructive tendencies inherent in human nature.

  13. #72
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    Quote Originally Posted by rob streeper View Post
    Hi Bob,

    I agree. I'm willing to make a controlled experiment on one of my saw plates, I don't really want to put prick marks all over a saw that I've paid hundreds of dollars for you know. Given the problems with thickness I propose to use a piece of 0.035" 1095 in it's as delivered state - no blue removal, and measure 25 or so test points with a distance between points of at least 5 mm. What do you think?

    Cheers,
    Rob
    Sounds good. I wouldn't do the saw map on a good saw, I'd just use an old or cheap saw.

  14. #73
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    Quote Originally Posted by RayG View Post
    Hi Rob,

    I've been following your hardness testing with interest, I have some real concerns about the conclusions you are drawing. I also have some concerns about validity of measuring the hardness of thin plate.

    First off, Rockwell 60 is so hard that a file would skate off it... I get chisels hardened to 60-62 and there's no way that would be suitable material for saw plate. No I don't doubt that you are reading those numbers on your tester, what I know is that they can't be correct.

    Second, 1095 maximum surface hardness in the "as quenched state" is around 66 Rc, that is as hard as you can get... and at that hardness it's as brittle as all get out, spring temper is usually down around 50 Rc... If you have a saw that's 60 Rc, I bet the teeth will snap like crazy.

    Third, You seem to be suggesting that 30-40 Rc is too soft for saw plate... I disagree, I think it would be fine, while it wouldn't be my choice. Promoting the idea that the sawmaker is using sub standard material is a bit of a long bow to draw...

    My hardness tester is an Avery 6402 , while I think I'd have trouble measuring 20 thou plate hardness accurately I'd still be able to get relative readings to compare with some of your results.

    Ray
    Hi Ray,

    I just posted some results of preliminary testing on one of the plates on the D-8 post that I hammered on. The hardness readings came out at roughly 63 in the region hammered and subsequently ground. Seems hammering has an enormous effect on the hardness.
    The thin material concern is why I bought this tester - it is designed specifically for doing tests on thin hard materials. Most of my measurements have been on the 15N and 30N scales with 45N measurements only where the thickness of the test article warrants.

    Cheers,
    Rob
    Innovations are those useful things that, by dint of chance, manage to survive the stupidity and destructive tendencies inherent in human nature.

  15. #74
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    Just to refresh everyones memory, here is the NIST guidance on hardness testing, including for thin materials.

    Rockwell Hardness Measurement of Metallic Materials.pdf
    Innovations are those useful things that, by dint of chance, manage to survive the stupidity and destructive tendencies inherent in human nature.

  16. #75
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    Quote Originally Posted by RayG View Post
    Hi Rob,

    I've been following your hardness testing with interest, I have some real concerns about the conclusions you are drawing. I also have some concerns about validity of measuring the hardness of thin plate.

    First off, Rockwell 60 is so hard that a file would skate off it... I get chisels hardened to 60-62 and there's no way that would be suitable material for saw plate. No I don't doubt that you are reading those numbers on your tester, what I know is that they can't be correct.

    Second, 1095 maximum surface hardness in the "as quenched state" is around 66 Rc, that is as hard as you can get... and at that hardness it's as brittle as all get out, spring temper is usually down around 50 Rc... If you have a saw that's 60 Rc, I bet the teeth will snap like crazy.

    Third, You seem to be suggesting that 30-40 Rc is too soft for saw plate... I disagree, I think it would be fine, while it wouldn't be my choice. Promoting the idea that the sawmaker is using sub standard material is a bit of a long bow to draw...

    My hardness tester is an Avery 6402 , while I think I'd have trouble measuring 20 thou plate hardness accurately I'd still be able to get relative readings to compare with some of your results.

    Ray
    Hi Ray. On Sawmill Creek George Wilson and David Weaver raised similar concerns regarding the validity of the test results.

    Having little knowledge on the subject of Metallurgy I am not in a position to form an opinion.

    Stewie;

    http://www.sawmillcreek.org/showthre...w-plates/page2

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