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I Forge Iron

Frazer

2021 Donor
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Everything posted by Frazer

  1. Glad I could be of some help, though there are others here much more qualified to give advice on knives than I am. Regarding the photos, I'm likely just being lazy/picky. There's nothing wrong with a link. If you do choose to embed them in a post just double click the image and reduce the size to reduce bandwidth. Oh, the fun of computers . I can relate I think Frosty is referring to grain boundaries and slip planes. My basic understanding is that there are more grain boundaries in a structure with smaller, more uniformly sized crystals. As you bend the material you are temporarily (elastically) or permanently (plastically) deforming each crystal. I'm not going to go into what dislocations are* but basically once a dislocation reaches a grain boundary it has no where else to go. By increasing the amount of grain boundary you are limiting the ability for these dislocations travel which increases the strength of the material. Each grain also has a particular plane where these dislocations like to move somewhat freely. This means it can be strong when force is applied in one direction, but weaker in another. If you imagine you have a vein of larger crystals that, on average, are oriented where these slip planes run part or all the way through your knife you now have a weakness where a crack can more easily form when force is applied in a certain direction. Smaller grains tend to be oriented more randomly which makes the material stronger in all directions. This is certainly a simplified version of what's going on. *If you're interested in looking at a 2D representation of dislocations and how they travel there is a cool video on youtube called "Experiments with the Bubble Model of Metal Structure 1952".
  2. I'll make the same comment here as I did there, take a (through hardened) file, break it and take a look at the grain. That will at least give you a reference. It's not my picture, but I think your 1-2x assessment is about right. The only trouble with assuming the grain you have now without normalizing and what you will have 5 knives from now will be the same is you may do more forging on the next one, you may get one hotter than than the previous one etc, etc. Unless you're making the same knife every time and your heat control is impeccable there is going to be variability in the forging process. When refining the grain you are trying to correct that variability with a definite, reasonably repeatable, process. Just my, non-bladesmith 2c. PS you can share your images by clicking the "choose files" hyperlink at the bottom of the editor. There's nothing wrong with sharing via Google images like you did. However, being selfish, it's easier to look at all three images in the same place rather than 3 separate links in different tabs and such. Not a big deal.
  3. George, I guess hardening and tempering your touchmark depends on the details that are there. Since Chimera's doesn't have too fine of details (that's not a critique, sometimes simple is good) I expect it would be just fine. The way I see it it doesn't hurt to harden and temper to brownish-purple. I stamp either a Z or my initials with little 3mm letters with a bit of a script font. I've used the B F and Z on hot steel most often by far. All of them will still stamp cold steel, which is their intended purpose. The key is to get in, get out, and cool. Don't let the punch sit there. (I know you know that, I'm just rambling...) I'll probably make my own touchmark someday, but I haven't come up with anything that I like yet. When I do I'll probably make it out of S7 or H13.
  4. I took a road trip down to southern PA to pick up my anvil. It seems they are less expensive by you, especially compared to NY. Given the condition and assuming the face is still hardened* I think a fair price would be in the 2-3 dollars per pound range. $3/lb is probably pushing it IMHO. That being said I'm sure you could find someone willing to pay more. The 1-0-3 stamp is the weight using the hundredweight system: 1-0-3 = 112lbs + 0 + 3lbs = 115 lbs *To test find a ~1/2" ball bearing and drop it from ~10" and see how far back up it comes in it's first bounce. This is generally expressed as a percentage. If you don't have a ball bearing tapping the face with light ball peen hammer can at least give you a rough idea how "bouncy" the face is.
  5. To my non-expert eyes it looks like you had voids in the canister. Use vibration to settle the powder into all the nooks and crannies. Vibration can be lots of taps on the side with something or other or, better yet, a sawzsall (with no blade) or other reciprocating tool pressed on the side. You'll be surprised how much stuff will fit into things when properly compacted.
  6. Ah, so a skewer of sorts. 316L is what we use at work for long term exposure to salt water. We electropolish everything, but that's overkill for what you're doing. I hand sanded the chopsticks I made with 304 (which is less resistant than 316 which is less resistant than 316L) and they have been fine so far, dishwasher and all. The higher the grit the better, but I think I stopped at 1500.
  7. What are you poking? How important is the corrosion resistance to you? There are many different types of stainless out there. The most common austenitic alloys are 304 and 316 and if you don't plan on doing any sort of heat treatment anyway it seems like a decent place to start... Maybe? It will be delicate at ~1/16" though.. Regardless, keep in mind you'll have to passivate the stainless after grinding to bring back it's stainless-ness. I use a 10% by weight solution of citric acid in water. Heat the water to ~140F, stir in the citric acid and soak the part for ~7 minutes. EZPZ.
  8. Agreed, what a tease! I actually talked to Dick about that one and 300lb #57 he had in stock back in January, but I'm holding out for something a little different. It will probably be a while. Anyway, congrats! I'm looking forward to hearing more about your experience with it.
  9. Makes sense to me. In certain instances you can get the thin toe of the top half to stick but not the rest. Particularly when the bottom half has more mass than the top, but more often than not you know within the first hit if it's going to weld or not.
  10. I would take pieces out of the scrap bin, scarf the ends and weld them together, grab another piece, weld it on, etc, etc. when I was done I would toss the bar back into the scrap pile from whence it came. The upside of this is not every piece is the same cross section, length, etc. do what you need to do to make the transitions smooth even if the bar itself wont be uniform. If you're having trouble, especially with smaller pieces, use a pair of tongs to squeeze the two pieces together while they're still in the fire. It helps if the tong jaws are hot as well. One thing I've said many times is flux isn't magic nor is it glue. If your welds wont stick it probably isn't because your flux doesn't have cockroach killer (boric acid) or metal filings or some other magic component in it. Other than practice it all comes down to 1) fire control 2) patience to let it get hot enough and (perhaps most importantly in the early stages) 3) Restraint to avoid the "just one more hit" urge when you still want to weld but the steel has fallen below the necessary temperature.
  11. I'm feeling a bit boulder now that he has a name. Perhaps he was a meteorite that fell and was struck by lightning thus fusing it to the surrounding stone? The fact that he has a long history is taken for granite. Mortar come later.
  12. I'm no rock-ologist, but could it be a piece of concrete with another rock embedded in it that was broken up for gravel? Okay leave the rock spotting to the rock spotters... I see sedimentary rock.
  13. We're out of sync Gravy! 4140 seems like a good choice, ~1040 would work just as well. By the way welcome aboard. Take a quick moment moment to read the following to get the most out of the site.
  14. Ok, so hold off for a year then. The pitting isn't going to make a difference during that time. If you have a welder, weld a piece of square tubing to a block of steel with 4 different radii on it and use it as an anvil block (as mentioned by Glenn). They are handy tools to have regardless. Though, I wouldn't make it as wide as your anvil face since for small pieces you sometimes need the far side of the anvil to come a little closer. If you don't have a welder, perhaps you know someone who may? The way I see it that is perfectly useful as is and is far better than I had starting out. Just my 2c. Edit: Missed your response. My anvil block is 4140, which works well. Hardening/tempering is suggested but optional. Even mild is harder than hot steel, so it will work, it just might need to be dressed more often
  15. I understand wishing to maintain some sense of anonymity, but as someone who has no smartphone and no social media (more to eliminate distractions than "fly under the radar") trust me, those who care enough to seek out your personal information already have the means to do so. I digress, to each their own. Do what feels comfortable to you. No judgement here. Back to the point. IMHO coal is a much more versatile fuel source and, at least by me, it's less expensive to run. Again, in my opinion, there are many things you can do with coal that you just can't do with a gas forge. The benefits to gas are the lack of dust/ash, (potentially) superior production work since there is less risk of burning up one of your pieces in the fire and the easy-bake oven aspect of "set it and forget it". Coal requires more maintenance, but comes with many upsides.... I cheat when staring up my forge. I lay down some paper and a handful of charcoal, pull the coke from my previous fire around that and light it up. I have hot steel in ~5 minutes. Much faster than waiting for the gas forge to heat up (at least the ones I have used which, admittedly, is very few). -- Okay, okay.. I'll admit I'm a little biased
  16. I buy my coal (Pennsylvania Smithing Coal) at the same place as the local blacksmithing school gets theirs. $12/50# bag (it recently went up from $10). The Coal Shop off 15A in Springwater.. NY is a pretty big place so that could be 10 minutes from you or 6 hours.. The NYSDB site is still down. We are having issues with reuploading the template after changing our hosting service. Hopefully it will be up in the next several weeks. If you let me know what region you're in I might be able to get you a contact for your local group at our next meeting (tomorrow). I don't usually track consumption per hour. I buy 10 bags at a time and go through them every few months, but I'm in the shop 5 days a week 4-6 hours per day.
  17. Thanks. The pattern is a relatively simple one, but I've gotten consistently interesting results from it. I draw the billet out into a roughly octagonal cross section and do a pretty tight twist. Then I flatten out the twisted bar, cut it into equal lengths and restack so a face with the twist going like this "\" is against a face like "/" and reweld. Then I forge the knife. I like the low layer patterns better than high layer billets. First because I'm lazy and second because you can see the interesting (random) features in the pattern when there are fewer layers. As you grind down through the layers you end up with, more or less, a V shaped pattern. The first picture shows the effect I was going for better than the second. It's not an exact science for me and the pattern always turns out a little different. I like to twist from an octagon rather than a square because I think it reduces the risk of cold shuts when flattening out the twists. The top and bottom of the first billet don't really get twisted so I always make sure those become the tang which is going to get covered up by the scales; it doesn't have to be very interesting.
  18. I use similar rods and have the same torch.. the petals aren't hot enough for the braze to wet out. Remember the base metal should ideally be melting the rod, not the torch (pieces breaking off is normal). It's possible to do, but barely. I would recommend forge brazing or buying an oxy-fuel torch. If you're forge brazing add some additional borax flux, the coating on the rods isn't enough. Save the bernzomatic for lighting the forge. Edit: I just read your next post where you used the forge, pardon my hasty response.
  19. Finished up a knife for my brothers friend. Stabilized zebrawood scales. The tang is skeletonized to bring the balance just in front of the foremost pin.
  20. According to my somewhat out of date version of NFPA 211 (2015) for unlisted caps the minimum distance between the underside of the rain cap and the top of the flue should be 0.7 times the long dimension (it assumes a rectangular cross section) of the covered flue. Applying this formula to a round cross section the pipe ID would be the long dimension. As an example my chimney has a 10" ID. So 10 * 0.7 = 7" which, coincidentally, is the same height as my store bought cap. -- Full disclosure, this number (0.7) is only specified for masonry fireplaces and my applying it to a round cross section might be misuse of the formula. Also, all of the caps for pipe ranging from 10-16" ID have a 7" gap (at least from the company that makes my particular stovepipe) so this formula, understandably, doesn't always hold up for listed parts. Just remember the higher you make the cap, the less precipitation it's going to stop (unless you make it bigger). 12" might be unnecessarily high, an 18-20" cap with an 8-9" gap seems reasonable IMHO. Just my 2c.
  21. CLB, what does the grain structure look like on the broken pieces?
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