Thread: Hardening of sawplates

Originally Posted by D.W.

S



Here's the quote of yours:



That's just not true. That's the issue.

...

Now, could it be that disston's saws changed after the 1930s when handsaws were in the death throes? I don't know. I don't buy those saws, their aesthetics are terrible and the golden era saws that most other folks have tested in the 40s hardness range lack nothing. Compared to the new backsaws, I find the old disston/atkins/etc. saws a bit lacking. Not because their steel is softer (though it feels so when filing), but because they have poor aesthetics but fat plates.

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David,

From the testing I've done and the limited testing done by others it seems that there are roughly three eras of Disston saw hardness. The pre-golden age, a time of minimal instrumental testing, the golden age where a great deal of expertise, experiential expertise that is, was applied to making Disston saws, and the last age where apparently aesthetics and to a degree functional performance suffered. The Disstonian Institute mentions a very brittle but not too hard backsaw that made just after the Civil War, well before Rockwell testing and only about 15 years after Disston started making steel. The golden age saws seem to be in the high 40's to low 50's and the last age runs a couple of points higher with some areas of exceptional hardness.

The Disston saws in my collection are all later saws. One was made sometime between the end of WW1 and 1928 and the others are WWII or later. These saws are all harder than the saws you sent me for testing. What happened at Disston to cause the changes? Was it sloppiness, cost-cutting or an intentional but misguided attempt to improve the products?

I find it very interesting that the 'golden age' of Disston saws started just before the introduction of instruments for hardness testing. Apparently Brinell testing came around 1900 followed in 1914 by Rockwell testing. I'm sure, given the interests of the Disston company, that they did at least some testing but I haven't been able to find any reports of what those numbers were. Just some anecdotal comments on the Internet.

As to the issue of 1095 I haven't found any rationale offered for it's selection. Perhaps somebody did some research that informed the choice but they apparently haven't published it very widely if at all, more likely in my opinion it was selected for it's combination hardness, price and availability and it was found to work well. Apparently no further questions were asked until I started looking into the issue.

The carbon content of 1095 is a bit higher than the Disston saws for which we have analytical results. The silicon content of 1095 is much lower than the Disston saws, effectively zero, and the manganese content is about double that of Disston steel. All of these factors will markedly change the performance of the steel. In fact, 1070 appears to be a better match for Disston steel than is 1095, (http://www.steelforge.com/aisi-1070/).
At this point I have no objective information supporting the choice of 1095 over any other similar hard steel alloy for use in hand saws. The first step in understanding this issue is taking measurements and I am grateful to you for providing the saws for testing. More testing is needed and it's within reason that more can be done.


Cheers,
Rob

Originally Posted by rob streeper

Hi Ray,

I found this: http://www.popularwoodworking.com/wo...history-lesson. Sounds about right to me.

I also found this: http://www.wkfinetools.com/contrib/c.../wenzloff2.asp

So really, the industry of custom saws is a very recent development. As to Disston's '52' I haven't found anything that they put in print on the issue.

Cheers,
Rob

In the states, a few people bought the independence saws, and then as a follow-on from Lie Nielsen. A LOT of people bought saws made by Mike Wenzloff.


George Wilson was making saws out of 1095 for the museum because out of the tools he made, it made the best backsaws (and apparently the professional craftsmen at wmsbg also felt that they were the best saws they had ever used, they've made that comment in public - and that includes the long saws). George was probably making backsaws out of 1095 before any of the boutique makers were out of frustration with the saws from england that were soft and of lower grade steel (because sharpening the saws fell onto the toolmakers - which was George or someone working for him). That would be why George would've (and did) hardness test old saws and new 1095, and why he has such a strong opinion, because he's seen more of the old tools than most of us ever will, and he's made more of the new ones than most of us ever will. I am not leaking anything from conversations with george, he has said all of these things openly on forums, and he provided the manufacturer that he was unhappy with, which I will not do on his behalf. (Also, George could've bought anything, he was working on the museum's dime with the ability to try anything he wanted from anywhere he wanted to get it.)


Until those guys came around, it appears that general perspective was that if you wanted a nice saw that was new, you had to buy a japanese saw. Something that would not fly in a museum that both:
* required craftsmen to use reproduction tools by rule, so as not to "use up" antiques
* required craftsmen to use period tools (using japanese saws would've been out of the question)


When I got into this stuff a decade ago, I recall most of the older members talking about using zona saws, japanese saws, etc, because the boutique saws were not yet widely used (even in 2005) and they had no had exposure to them, and some of them not being toolmakers were offended by the price that wenzloff was making saws (which in my opinion was low to begin with because he was doing an incredible amount of finishing work on them and working himself half to death). Several of the members on other forums (who are still on them) have described starting in the 70s and getting into japanese saws and planes because otherwise you could not get good new tools at the time.


The boutique thing is recent, and it seems to have exploded with the internet because people got the boutique backsaws and liked them much better than anything else they've had (i'm sure there are exceptions, but that's been the reaction of most).

Originally Posted by rob streeper

As to the issue of 1095 I haven't found any rationale offered for it's selection. Perhaps somebody did some research that informed the choice but they apparently haven't published it very widely if at all, more likely in my opinion it was selected for it's combination hardness, price and availability and it was found to work well. Apparently no further questions were asked until I started looking into the issue.

I don't know if you're going to find it. Anything Mike Wenzloff would've said is probably gone in the history of archives and difficult to find.

I think the question came out before about old saws being hammered and tensioned, and why wasn't that done on the 1095 long saws, and George or Mike W could give you an answer for that. Mike tapered long saws, something a lot of people don't do, and at least at one point, he was doing it with a tormek (stone). I know this only because he was brought up as being the only person to ever actually get a tormek to wear out - and only because he was using it in a manner that they couldn't have seen.

You could ask George over on SMC why they didn't tension and hammer saws at the museum, they'd have done probably whatever was done to seaton chest saws. People are using those saws professionally to do paid work, though, see mack headly's shop via google, and I believe Mack may have been the one who said in a presentation that they were the finest saws he ever used.

As to disston, I refer to the golden era because it would've been a very competitive time between saw makers where disston was making both files and saws, and they would've needed to please on average a professional user rather than a homeowner who would be more likely to buy based on catalog spec. A lot of later disston 2nd line saws that were pretty gross were sold to homeowners (I can recall two that my dad had). The golden era saws, even without commercial availability of hardness testing, would've been developed based on whatever pleased professionals at a given price point, and from the standpoint of context of use would be the best barometer.

It's my opinion that the saws before then are inconsistent and you'd need a larger sample. Of all of the long saws I've used, the ones right around the turn of the century seem to be (to me) the most practical, and almost to a T every one of them is consistent as long as they are first line saws of a comparable model.

Originally Posted by D.W.

In the states, a few people bought the independence saws, and then as a follow-on from Lie Nielsen. A LOT of people bought saws made by Mike Wenzloff.


George Wilson was making saws out of 1095 for the museum because out of the tools he made, it made the best backsaws (and apparently the professional craftsmen at wmsbg also felt that they were the best saws they had ever used, they've made that comment in public - and that includes the long saws). George was probably making backsaws out of 1095 before any of the boutique makers were out of frustration with the saws from england that were soft and of lower grade steel (because sharpening the saws fell onto the toolmakers - which was George or someone working for him). That would be why George would've (and did) hardness test old saws and new 1095, and why he has such a strong opinion, because he's seen more of the old tools than most of us ever will, and he's made more of the new ones than most of us ever will. I am not leaking anything from conversations with george, he has said all of these things openly on forums, and he provided the manufacturer that he was unhappy with, which I will not do on his behalf. (Also, George could've bought anything, he was working on the museum's dime with the ability to try anything he wanted from anywhere he wanted to get it.)


Until those guys came around, it appears that general perspective was that if you wanted a nice saw that was new, you had to buy a japanese saw. Something that would not fly in a museum that both:
* required craftsmen to use reproduction tools by rule, so as not to "use up" antiques
* required craftsmen to use period tools (using japanese saws would've been out of the question)


When I got into this stuff a decade ago, I recall most of the older members talking about using zona saws, japanese saws, etc, because the boutique saws were not yet widely used (even in 2005) and they had no had exposure to them, and some of them not being toolmakers were offended by the price that wenzloff was making saws (which in my opinion was low to begin with because he was doing an incredible amount of finishing work on them and working himself half to death). Several of the members on other forums (who are still on them) have described starting in the 70s and getting into japanese saws and planes because otherwise you could not get good new tools at the time.


The boutique thing is recent, and it seems to have exploded with the internet because people got the boutique backsaws and liked them much better than anything else they've had (i'm sure there are exceptions, but that's been the reaction of most).

David,

Yes, it's a bit surprising that this 'industry' is so young.

You don't know me very well so I'll give you some information about my work. I've been making precision measurements for better than 30 years. I've been involved in quality management for more than 20 years. I've done this work using devices ranging from the simple mechanical instruments like hardness testers to instruments that cost millions and fill a couple of large rooms. On the strength of this experience I'm comfortable saying that I know how to take measurements and I know how to analyze the results.
My professional work has taught me another thing about people: Many people will reject analytical results if those results don't fit with their prior expectations, I call them refuseniks. There is another group that accepts the unexpected results, figures out what happened, produces new samples and ultimately achieves their goals. I call these people scientists. The refuseniks often fail professionally and I've had the unique pleasure of seeing a few of them crash and burn first hand.
I can't tell you how many times I've had people say 'Are you sure that thing's calibrated...' or sum such garbage because the results showed something other than what they wanted them to show. I've learned to take precautions against challenges of that nature by always using calibrated instruments, always checking the instruments for proper operation and always repeating measurements, especially if the results differ from expectations. These practices are really just good science.
So for me, hardness measurement instruments don't present much of a challenge. They are very simple devices and though tweaking them up is time consuming it's very straightforward.
The numbers don't care whether or not we like them, they simply are. The tightness of my results also speaks to the quality of the data. Until somebody marshals the resources to do comprehensive testing of older saws my results are the best information that is freely available on this subject. It would be really good if somebody who has a tester would do some experiments with older saws and post the results on this site.

Cheers,
Rob

Originally Posted by D.W.

I don't know if you're going to find it. Anything Mike Wenzloff would've said is probably gone in the history of archives and difficult to find.

I think the question came out before about old saws being hammered and tensioned, and why wasn't that done on the 1095 long saws, and George or Mike W could give you an answer for that. Mike tapered long saws, something a lot of people don't do, and at least at one point, he was doing it with a tormek (stone). I know this only because he was brought up as being the only person to ever actually get a tormek to wear out - and only because he was using it in a manner that they couldn't have seen.

You could ask George over on SMC why they didn't tension and hammer saws at the museum, they'd have done probably whatever was done to seaton chest saws. People are using those saws professionally to do paid work, though, see mack headly's shop via google, and I believe Mack may have been the one who said in a presentation that they were the finest saws he ever used.

As to disston, I refer to the golden era because it would've been a very competitive time between saw makers where disston was making both files and saws, and they would've needed to please on average a professional user rather than a homeowner who would be more likely to buy based on catalog spec. A lot of later disston 2nd line saws that were pretty gross were sold to homeowners (I can recall two that my dad had). The golden era saws, even without commercial availability of hardness testing, would've been developed based on whatever pleased professionals at a given price point, and from the standpoint of context of use would be the best barometer.

It's my opinion that the saws before then are inconsistent and you'd need a larger sample. Of all of the long saws I've used, the ones right around the turn of the century seem to be (to me) the most practical, and almost to a T every one of them is consistent as long as they are first line saws of a comparable model.

The oldest comment on the issue I've found is the one linked above by MikeW from 2006. Remarkably hard to pin this information down and the difficulty suggests to me that the number wasn't the result of any kind of analytical reasoning.

Like I've said above, I use 1095 and I have saws that are made with 1095 and they work well for me. Can they be better? I don't know but I'm willing to ask the questions and do the work to find out.

The problem with sample size may never be resolved for the older Disstons. I can just imagine the response of a collector to a request to test a mint-condition golden era saw. The surface roughness and deformities of junker saws makes obtaining accurate readings much more difficult. Resurfacing the saws introduces problems as well.

The golden era may have come about because of Disston's policy of lifetime employment. As the workforce grew more experienced the products got better reaching a pinnacle before WW1. Then the business office got involved and started mandating shortcuts and / or some of the old hands stopped working and failed to pass on their experience to the following generations. Who knows? My goal is to do better and if there's a way I will. I'm going to start experimenting with cryogenic treatment soon...

Cheers,
Rob

I think you are a bit hasty in assuming that your results are the best available. Your results may be the largest in number, but that doesn't automatically mean they are the best available.

I wouldn't fit your refusenik category, as I professionally work with data every day and one of the things that I have responsibility of doing is to decide whether or not the data is flawed or inconsistent. In this case, there is other data, and the other data is similar from other sources. Your initial data is not similar to those sources. Not knowing anything about the other sources, except that one was done by a professional (George) and the other was done under the supervision of a professional (can't remember who did the other set), it would be very unlikely that multiple sources of similar data would be incorrect and yours correct. The odds are against it and we'd have to figure out why.

Also, someone who had more experience with saws and less experience with "measuring things" is likely to have a much better chance of providing relevant data and drawing conclusions from it. They will immediately be able to spot problems with using a hardness number in the 60s and then recalling that they were able to file a given saw that is given that reading. I believe your inferences and use from the tools are likely to more reliable than someone who had knowledge of neither, but likely not as useful as someone who had long-term knowledge and experience in both, and probably unlikely to be as useful as someone who had long-term exposure to saws (and their being made professionally) and a year or two of experience with measuring devices.

Making a determination like that on a limited data set is my job. Literally.

I'm assuming that you are painting yourself as the scientist and me as the refusenik, but what you are doing is equivalent to being a measurement technician, and not a scientist (a scientist would have expert experience in whatever area they were drawing conclusions about), and I am certainly not a "refusenik".

Originally Posted by rob streeper

The golden era may have come about because of Disston's policy of lifetime employment. As the workforce grew more experienced the products got better reaching a pinnacle before WW1. Then the business office got involved and started mandating shortcuts and / or some of the old hands stopped working and failed to pass on their experience to the following generations. Who knows? My goal is to do better and if there's a way I will. I'm going to start experimenting with cryogenic treatment soon...

Cheers,
Rob

Again, you're insulting Mike by suggesting that his choice in saw steels was done based on limited analysis. I have not seen another person who was as practically involved in trying to make the best saw possible for a reasonable price as was mike.

I think if you're not trying to build saws out of 440C or something, people are going to lose interest when you start talking about cryogenic testing, because saws are used at a much higher state of wear in general than razors, knives or chisels. Even in planes and chisels, it's arguable that it's not very useful. Commercial knives in 440C are too hard to tell if it's useful, and only in razors would one suggest it's useful and the benefit of it needs to be at a hardness level that is not attainable for saws because they will instead be brittle.

In short, the size of the carbides is not going to matter much in saws.

Originally Posted by D.W.

Again, you're insulting Mike by suggesting that his choice in saw steels was done based on limited analysis. I have not seen another person who was as practically involved in trying to make the best saw possible for a reasonable price as was mike.

I think if you're not trying to build saws out of 440C or something, people are going to lose interest when you start talking about cryogenic testing, because saws are used at a much higher state of wear in general than razors, knives or chisels. Even in planes and chisels, it's arguable that it's not very useful. Commercial knives in 440C are too hard to tell if it's useful, and only in razors would one suggest it's useful and the benefit of it needs to be at a hardness level that is not attainable for saws because they will instead be brittle.

In short, the size of the carbides is not going to matter much in saws.

I'm not insulting Mike Wenzloff because: 1) I don't know if the 2006 MikeW is Mike Wenzloff and 2) I don't know that Mike Wenzloff made the decision that set the standard for the industry. I suspect it was done earlier, likely when Independence was working in 1996-1998. But again, none of us knows because the originator of the use of 1095 hasn't stepped forward.

Cryogenic processing works on many different kinds of steel. For instance it's very popular for gun barrels, knives, drill bits and myriad other steel products. I'm not after hardness, but scratch resistance. I anticipate cryogenic hardening followed by tempering to different hardness values around 50 or so.

Do dovetail saws 'need' to be better? Most of us don't even need a dovetail saw in the sense that we need air and water, we want saws and I want my saws to be interesting to me. I want to try cryoprocessing because I want to see what the results are. I suspect that the result will be better but I know that it will be interesting, if not to others, then at least I'll be amused.

Originally Posted by D.W.

I think you are a bit hasty in assuming that your results are the best available. Your results may be the largest in number, but that doesn't automatically mean they are the best available.

I wouldn't fit your refusenik category, as I professionally work with data every day and one of the things that I have responsibility of doing is to decide whether or not the data is flawed or inconsistent. In this case, there is other data, and the other data is similar from other sources. Your initial data is not similar to those sources. Not knowing anything about the other sources, except that one was done by a professional (George) and the other was done under the supervision of a professional (can't remember who did the other set), it would be very unlikely that multiple sources of similar data would be incorrect and yours correct. The odds are against it and we'd have to figure out why.

Also, someone who had more experience with saws and less experience with "measuring things" is likely to have a much better chance of providing relevant data and drawing conclusions from it. They will immediately be able to spot problems with using a hardness number in the 60s and then recalling that they were able to file a given saw that is given that reading. I believe your inferences and use from the tools are likely to more reliable than someone who had knowledge of neither, but likely not as useful as someone who had long-term knowledge and experience in both, and probably unlikely to be as useful as someone who had long-term exposure to saws (and their being made professionally) and a year or two of experience with measuring devices.

Making a determination like that on a limited data set is my job. Literally.

I'm assuming that you are painting yourself as the scientist and me as the refusenik, but what you are doing is equivalent to being a measurement technician, and not a scientist (a scientist would have expert experience in whatever area they were drawing conclusions about), and I am certainly not a "refusenik".

Technicians do what they're told to do, scientists decide what to do.

It's going to be hard to tell if they're better with cryo, but 50 is a good target. Scratch resistance may make them a bit tougher to file, but I don't think at 50 that it'll be too much of a problem.

As for what type of things you test, certainly you can do whatever you'd like. Proportion is something I would like to see studied, and before Mike burnt himself out to some extent, he was obsessed with making a good saw and how he could do it for less.

Good often being proportions, as the saws before the boutique re-start were pretty bad in proportions, in my opinion. You can see it looking at a lot of them, and some of the makers of those saws still are making them the same way (I don't know who the saws sell to, I've never seen on in person, and they may not care if they don't sell many in the first place).

If you can make a saw that:
* feels good to use
* works at a good rate through wood
* gives good results
* looks good
* has easy maintenance

That will be a ...well, not just a good saw, but a great one.

Originally Posted by rob streeper

scientists decide what to do.

As do tinkerers.

You can define a broad range of scientists, but those who are regarded as professionals usually have a very great deal of background in what they're talking about. Your focus is to make a better saw, and you're an expert in measuring. This would be more scientific in a narrower sense if your focus was to better use measuring tools and the saws just happened to be the subject.

Because scientists can be such a broad range of things, but often involve people who are more tinkering or measuring, it's more practical to use an applied sense here and a narrower range. In credentialed science, the context has to be not just measurement of data, but that there is an obligation on the communicating scientist to be definitive (not speculative, unless definitive is not available) and an obligation to provide data in such a way that the end user is going to draw the correct conclusion for what it was intended.

Originally Posted by D.W.

It's going to be hard to tell if they're better with cryo, but 50 is a good target. Scratch resistance may make them a bit tougher to file, but I don't think at 50 that it'll be too much of a problem.

As for what type of things you test, certainly you can do whatever you'd like. Proportion is something I would like to see studied, and before Mike burnt himself out to some extent, he was obsessed with making a good saw and how he could do it for less.

Good often being proportions, as the saws before the boutique re-start were pretty bad in proportions, in my opinion. You can see it looking at a lot of them, and some of the makers of those saws still are making them the same way (I don't know who the saws sell to, I've never seen on in person, and they may not care if they don't sell many in the first place).

If you can make a saw that:
* feels good to use
* works at a good rate through wood
* gives good results
* looks good
* has easy maintenance

That will be a ...well, not just a good saw, but a great one.

I'm going to use one of my heavily taper ground tenon saws for a test subject so that setting the teeth is not needed. I plan to test it before cryo, after cryo and after tempering.

Give it a shot on hardwoods and softwoods and let us know how it goes.

Originally Posted by D.W.

The level of discussion here is higher and the average reader in this thread more experienced.