Bike Mike Posted December 10, 2009 Report Share Posted December 10, 2009 There has been much debate for some time of the metal used in our reps, or at least what the dealers claim, verses what a reps are really made of. I know recently Lani has posted reviews about his new DSSD made from 316F. Also, about a month or so back there was a thread in the general discussion area regarding 316L vs. 316F, which I chimed in on regarding myself being able to run a full battery of metallurgical tests during first part of December....well that time is here.... Disclaimer: These test were run using the watch case and components that I have. These results do not reflect what “ALL” reps are. There very well could be a whole mess of different grades, types, formulations that are used by each manufacture. It would be nice to do whole range of test on the different piece, form different watch brands, from different manufactures, claiming different metals, ie. 316F, alignment of the plants and time of manufacturing. But this was not the case, so please take this information as you like, but my finding are not necessarily going to reflect the material type for the watch(s) you own...I will say, that I hold little doubt that the lack of QC correlates to different material formulations relative to each batch! I am going to run both PMI (Positive Material Identification) as well as destructive testing to confirm the results on the bracelet clasp, bracelet links, case and case back. I will apologize now as I will not be able to post pictures of the tests being run, we have a very strict NO Camera policy unless you have authorization. Well I don’t have authorization and I do not want it. I would love nothing more to show videos of the testing process here as some of the reactions during spark and acid testing can be pretty cool. I will posts pics of the aftermath once I get the samples home. I will post links to some of the testing so you can read about how a specific test is done if you wish. So here is what I have...A full case and bracelet set from a my dead Daytona, purchased from one of our dealers who will go unnamed. Case and Bracelet material is, as stated per website "316L". Lets find out...Case Back first. What is this sticking to the case back? Magnet! 316L stainless steel is Austenitic. The Austenitic family of Stainless Steel (SS) are generally non-magnetic. Now you can trigger a magnetic response in this family of SS through cold working (think bending a soup can lid back and forth until it breaks), however 316 is resistant to this effect due to the high levels of Nickel. So we have already established this is not 316L, what is it? Being that it is Magnetic and I know that the forming of these case backs is not by cold forming, that moves us to the Martensitic or Ferritic family of SS. So we move from 300 series to 400 series. Don’t start thinking this is a good thing because 440 falls into this series and 440 SS is used in all things great. So the next test is Spark testing. This produced whiteish sparks, almost like comet tails. This points me towards the Martensitic family. I skipped the hardness testing and move right into the fun Hydrochloric Acid test. A few drops of HCL, caused a quick reaction creating greenish solution. Now we are getting some where. 409 or 410 SS it is. PMI scan testing showed 11% Chromium, 0.048% Nickel and 0.084% Carbon. Reference my Machinist Handbook and SAE book.....409 SS it is! What else is made from 409 SS? Automotive exhaust. Basically one of the cheapest SS you can purchase. CLASP: I am calling the clasp, this piece. So after finding out that the case back was made from 409 SS, I already began to set my assumptions for how the rest of this was going to turn out. So following the same process cadence of the case back I took my magnet to the clasp. No magnetic attraction what so ever. This was encouraging as this keeps us in the Austenitic family of SS. This family most consists of 300 series, with some 200's and the famed 904L. Onto spark testing, which yielded very short sparks that were red in color along with a couple of forks. Forking, is the splitting of the spark. So instead of one comet like tail, you have one that branches of into a few, like a fork. Looking at my SAE references, this cover 308 and below grades along with 316. Oh things are looking up. Onto the HCL Acid test. A couple drops of HCL onto the clasp and....waiting...more waiting...went for hour-and-a-half lunch and finally some minor attacking of the acid that was very sloooooow. If the reaction was fast producing a green solution or a nasty smelling gas, this would have meant the SS was 308 or below. Since we got a nice slow reaction, this mean the clasp is 316! You can see the acid etch on the top surface of the clasp here. Fingers crossed for low carbon content. PMI testing showed 16.5% Chromium, 10.2% Nickel and 0.075% Carbon. Very low carbon but not low enough to be 316L. So 316 SS it is! Really this is not surprising, the clasps are formed using simple stamping tools, punch & die, that form and trim these out of 316 SS sheets which is readily available at low costs due to it popularity. It is probably easier for the manufactures to get 316 then anything else. BRACELET: I used 2 links of the bracelet. 1 link will be used for material testing, the second link will be used under a high powered microscope to show everyone the grain structure. Like the case back and clasp I started out with holding a magnet up to the links with the steel pins removed so not to create a false positive. No, magnetic properties for the links so we stay in the Austenitic family. Again 200 to 300 series SS. Spark testing, which did not yield any results, as the stone grabbed my unsecured sample and riffled it across the lab. Good thing I had the rest of the bracelet with me. Sample now secured and...nothing....WTF! After a top off of my coffee and a few phone calls to find out what college noob was in the lab doing what to the equipment. Come to find out one of those fresh out of college noobs took it up himself to clean the stone and did not like how fast a rake stone was working for him. So he helped it with a little release agent (used for sample release from Bakelite, the stuff is slicker then greased owl sh!t) that was in the lab!!! SOAB! Another coffee later, and about 15 minutes of cussing changing the stone, dressing it, etc. I was ready to go. Like the clasp the sparks were red in color along with a couple of forks. Oh kind of promising for 316! The HCL test at first seem promising with no reaction, split second later, gas was forming with one hell of a pungent smell. Almost like bad eggs. So I poured on more HCL and called over the college noob that thought he was doing me a favor cleaning the spark stone. Unfortunately he was smart enough then to listen to me telling him to stick his head inside the ventilation hood. Knowing how the HCL test with the clasp went, this was not 316. I cleaned up the sample and exposed the other side to Sulfuric Acid. Very fast acting attack with small dark crystals forming. 304 SS! PMI testing gave me 18% Chromium, 8% Nickel and 0.08% Carbon. Some of you maybe more familiar with the other calling of 304 SS which is 18/8. These results are not surprising either as 304 is the most common grade of SS. Almost 50% of all stainless steel made if 304 being used in applications such as forging, machining and can be further enhanced for welding with the further reduction of carbon. You can see the left over effects from the spark test and acid burning. The second link was taken and encased in Bakelite. This is like a half-dollar sized hockey puck that holds the sample for hardness testing and other testing. The puck is cut down the middle through the link and polished to a mirror finished. Think of cutting a frozen jelly donut in half. The cooked dough is the Bakelite and the metal is the jelly. The final phase of polish involves adding a very small amount of ridiculously over priced diamond paste to perfectly flat horizontally rotating polishing stone. This further enhanced the metals polish allowing us to see the grain structure. What appears to be about 1/2” in distance is really about 1X10^-6 meters. From this we can see the grain structure of the SS. Not to get into too much detail, but the heavy areas of black are carbon inclusions. The almost shiny particles in the lower left of the picture are Chromium. Over all looking at this micro-structure, I can tell you the manufacturing process had no control over their temperature as the grain structure show indication of phase transformation. CASE: The final piece. Will we get lucky and get what our dealers have claimed (well at least for my watch anyway), or will it be yet another piece that is made up of a stainless steel other the 316/L. So I popped the crystal out as I doubt that is going to tell me anything and cut the case in half. One half will be used for my standard battery of testing and the other will be used for hardness testing. I elected to do HARDNESS testing as some members have attested here that while working on their pieces they have found it difficult to cut or drill into some areas of the case. I suspect carbon inclusions, which are essential clumps or carbon deposits that can form during manufacturing especially with poor QC and over heating the metal taking it through phase transformations. I will explain phase transformations in another update to this post at a later time as it is relevant to the properties of our watches. So mixing it up a little bit so not to keep anyone is suspense, I jumped right into the PMI testing. The results were Quote Link to comment Share on other sites More sharing options...
gioarmani Posted December 10, 2009 Report Share Posted December 10, 2009 Interesting. Keep 'em comin'. Quote Link to comment Share on other sites More sharing options...
Ronin Posted December 10, 2009 Report Share Posted December 10, 2009 Cool... I love science! Quote Link to comment Share on other sites More sharing options...
KB Posted December 10, 2009 Report Share Posted December 10, 2009 This is very interesting, hardly surprising knowing China's all consuming quest to make things as cheap as possible, but still it is interesting to have it confirmed like this. Ken Quote Link to comment Share on other sites More sharing options...
krpster Posted December 10, 2009 Report Share Posted December 10, 2009 Great analysis. Cool to have access to this kind of testing equipment. Now don't keep us hanging for the rest Quote Link to comment Share on other sites More sharing options...
Guest techlogik Posted December 10, 2009 Report Share Posted December 10, 2009 So you are going to leave us hanging with that?!?!!? We need to all pitch in, donate a few bucks, get a Josh 316F DSSD, have it evalauated....I will ROFL if it isn't...just as I think it isn't. Quote Link to comment Share on other sites More sharing options...
Samurai Posted December 10, 2009 Report Share Posted December 10, 2009 Interesting stuff. Quote Link to comment Share on other sites More sharing options...
lanikai Posted December 10, 2009 Report Share Posted December 10, 2009 Good stuff.. regardless it could be a rock from Mars.. but whatever they are using is sure looking good (in the new steel).. as I noted in my review.. to me it has more chromium in the steel, thus it's brightness and sheen... whatever it is I like it for it's aesthetics.. colour wise .. I'm glad they came out with it(316f).. it sure beats the old steel they were using. for visual closeness to the gens. as I don't plan on getting these close to water except in the rain.. thanks for sharing AC/Lani Quote Link to comment Share on other sites More sharing options...
AllergyDoc Posted December 10, 2009 Report Share Posted December 10, 2009 Very interesting stuff. Quote Link to comment Share on other sites More sharing options...
maxman Posted December 10, 2009 Report Share Posted December 10, 2009 Nice job Mike, well done Indeed, thanks Mike Quote Link to comment Share on other sites More sharing options...
Bike Mike Posted December 10, 2009 Author Report Share Posted December 10, 2009 So you are going to leave us hanging with that?!?!!? No I am not going to leave you hanging like that! This just takes time as I have "real work" that I am doing. The case and bracelet will take longer as I want to get some microscopic images of the grain structure that shows the Carbon inclusion, which is why some members are having issues when drilling lug holes and such. Quote Link to comment Share on other sites More sharing options...
FxrAndy Posted December 10, 2009 Report Share Posted December 10, 2009 Great work Mike Quote Link to comment Share on other sites More sharing options...
Member X Posted December 10, 2009 Report Share Posted December 10, 2009 This is great stuff! It's good that we have members of the community able to do this for the benefit of all Will look forward to the rest of the tests! Quote Link to comment Share on other sites More sharing options...
slickdick Posted December 10, 2009 Report Share Posted December 10, 2009 Excelent info. I run the mangnetic test on serveral watches i have at my work. Breitling BCE v1: Bracelet: magnet wouldnt stick. case: magnet sticks although not very solid a bit of a shake and the magnet drops. WM9 yachtmaster: case and bracelet same as the BCE case, sticks though ever so slightly DSN PAM 27b: Same as with the WM9 and BCE case. The buckle however would not know nothing from the magnet. Looking forward to the next episode of mythbusters. Quote Link to comment Share on other sites More sharing options...
RWG Technical Posted December 10, 2009 Report Share Posted December 10, 2009 Excellent info, thanks for this. Quote Link to comment Share on other sites More sharing options...
coolfire Posted December 10, 2009 Report Share Posted December 10, 2009 WOW.... Outstanding knowledge base building up on here...Thanks Mike! Once your thread is complete, I hope that this will be a sticky somewhere... Quote Link to comment Share on other sites More sharing options...
hackR Posted December 10, 2009 Report Share Posted December 10, 2009 Nice work, Mike!... I worked for a company that sourced ss products for consumer and food service markets (silverware/flatware/serveware/etc) from many different factories throughout Asia...even though these factories were "certified" we ran into mix issues...these factories made all sorts of items for all sorts of industries...so knowing the what/where of these factories and their capabilities is a piece of the puzzle...Mike's comment on ss automotive exhaust level steel could very well mean that there's a factory that makes exhaust and watch cases... Quote Link to comment Share on other sites More sharing options...
P4GTR Posted December 10, 2009 Report Share Posted December 10, 2009 This is very interesting! Now we're talking, I love threads like this! I have a very strong magnet here with me at my desk at work, and I'm wearing my Skyland V3. Bracelet (links) No magnetic attraction at all. Bracelet Buckle- light attraction, barely sticks. Watch case- no magnetic attraction at all watch case back- STRONG magnetic attraction. Quote Link to comment Share on other sites More sharing options...
Bike Mike Posted December 10, 2009 Author Report Share Posted December 10, 2009 This is very interesting! Now we're talking, I love threads like this! I have a very strong magnet here with me at my desk at work, and I'm wearing my Skyland V3. Bracelet (links) No magnetic attraction at all. Bracelet Buckle- light attraction, barely sticks. Watch case- no magnetic attraction at all watch case back- STRONG magnetic attraction. Neodymium magnet? If it is a rear earth magnet, there is a good chance you can magnatize your hair spring. Z, I think are going to have a sudden increase of watches in needing demagnetization and regulating! Working on the clasp buckle now. Should have it finished today and updated tonight. So far it has passed the magnet test, so we are batting for 300 series so far. Quote Link to comment Share on other sites More sharing options...
PeteM Posted December 10, 2009 Report Share Posted December 10, 2009 Thanks for your efforts Mike, thats a really useful thread look forward to the follow up - cheers Quote Link to comment Share on other sites More sharing options...
specialvat Posted December 10, 2009 Report Share Posted December 10, 2009 Top info, cheers for going thru it all with us. Quote Link to comment Share on other sites More sharing options...
andreww Posted December 10, 2009 Report Share Posted December 10, 2009 Neodymium magnet? If it is a rear earth magnet, there is a good chance you can magnatize your hair spring. Z, I think are going to have a sudden increase of watches in needing demagnetization and regulating! Working on the clasp buckle now. Should have it finished today and updated tonight. So far it has passed the magnet test, so we are batting for 300 series so far. LOL, I just remembered that I had a very strong magnet stuck to the side of my filing cabinet. I eagerly began touching it to the bracelet, case and caseback of the watch I happen to be wearing. No magnetic attraction whatsoever!!!!! Then it dawned on me that my chrono avenger is made of titanium. I'm just a f__king idiot sometimes Quote Link to comment Share on other sites More sharing options...
jmb Posted December 10, 2009 Report Share Posted December 10, 2009 Excellent information! I'm looking forward with great interest to your "carbon" tests. Quote Link to comment Share on other sites More sharing options...
Toadtorrent Posted December 10, 2009 Report Share Posted December 10, 2009 Excellent info Mike...right up there with the GGG thread...and that is no slight compliment!! Quote Link to comment Share on other sites More sharing options...
southcoast68 Posted December 10, 2009 Report Share Posted December 10, 2009 409 SS, she's real fine, my 409 Thanks for all the hard work on this, its fascinating reading, and I am looking forward to read the rest. Now correct me if I am wrong here, but just touching a caseback with a magnet to test attraction, I would imagine, is no good for a watch. However, since some casebacks are exhibiting magnetic properties, I would think that these watches would exhibit all kinds of weird problems even without being near a magnet. Think of it, your caseback is a magnet, and right up close to the movement 24/7, with no Faraday cage or shielding. Thanks again for the research. CHeers Quote Link to comment Share on other sites More sharing options...
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