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John N

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Everything posted by John N

  1. Hi @Will Robertson - sorry for delay in reply, not been on forums much, life got in the way! Brief answers..... I cold forge stone cold after a full anneal. I drop my normalisation temps by about 20 deg C per cycle, so, for example 820, 800, 780. (or slightly below critical on the last cycle). I don't understand the science of this, but do it anyway, and it works for me! I don't use scrap steel for the core. The core steel is really cheap in the overall cost of things. Nowdays I use Aogami super blue from Japan. Its still only $15 a blade if you are forging to near finished dimensions (and it adds $100 to the sale price of a chefs knife) - O1 is an epic core steel, and costs virtually nothing. I soak the newly set weld at full welding temp after setting it. My forge is not that adjustable as it has a hard lining so a very slow thermal response! - guessing 1100c I use borax as flux, but I suspect its a placebo for me, and the weld would stick without it. My forge is pretty neutral atmosphere, and I can tweak it rich. If I am using pure Ni in the san-mai billet as a barrier layer I now seam weld it all to keep the air out. Ive had too many sneaky failures on final grinding to trust an 'open' to atmosphere weld. You don't need to knock cr*p out of a billet to weld it, just set the weld as you would normally forge, then give it a soak, and go at it! If the conditions are right it will pretty well weld itself. I dropped a billet once taking it out of the forge, and it all stuck together hitting the floor
  2. Its a sweet looking little anvil! - @Alan Longmire - Dudley is in the Midlands of the UK, not anything to do with Sheffield in Yorkshire! - Its the equiv of me confusing Canada and USA in terms of winding the locals up
  3. It looks like its got a forge stiffy When I mow though my other 200 unfinished projects Ill give this a try, Ta!
  4. Great you are healing well, and no horrible infections. Thanks for the update, I occasionally wondered how you got on! - you will be back to new normal in no time. I visited a factory once a few years ago to collect a job, and their van driver / labourer had no hands, just stumps. I watched him load a van with fork truck, and somehow do the ratchet straps up. I had a real good think that night that some of my life excuses for not getting stuff done were really not valid! I'm sure the chap would have been financially better off staying at home on welfare. Strong man!
  5. Sounds pretty crazy construction! If you know you can do it, you can. I've only made 1 sword, I just suddenly had to make it - and I did (12 years ago now) No way on earth I should have been able to make it with my skill set, but it just kinda emerged from the fire Not sure if the link below will work to take you to the instagram post, if not look up @non_jic and scroll back a lot on my feed if you want to see it. 10 bar construction. Funny thing is, i've not really wanted to make one since, even though I periodically find that one and cant believe I made it. I realise now, having handled other swords it needs to loose a bit more weight on the grinder, but the muse has not returned yet. Go for it! https://www.instagram.com/p/Bn9liUXgJ_d/?utm_source=ig_web_copy_link edit... I would leave the Ni out of the billet on an edge wrap. If you don't set the weld perfect, first time, no messing, I have found it will not stick whatever you do. I still mess up san-mai with pure Ni barrier in it. And your Ni would be very exposed to oxidation on an edge wrap, not saying you can't, but it would be tricky for sure!
  6. Crikey! hope you are healing up OK. That's a horrible accident. I wear a heavy cotton boiler suit when I work, I will be very careful to keep my sleeves pulled up when grinding from now on. Ive had a finger end dragged in before and that was bad enough.
  7. of course! chase the crack out and make a smaller blade You wont feel satisfied, and will have to start again though!
  8. If was forced to hand forge it, my starting billet would be 4" x 1.25 x .75 thick. With a bit of loss I would hope to get a decent sized blade from this stack.
  9. Glad the pointers were helpful! I have spent a lot of time chasing down the nuances on this type of blade. One thing I have come to accept now is you know in your heart of hearts when a blade is off to the scrap bin! there is a point its no longer worth working on it I usually kick off with a big billet, power hammer it down to a piece of stock, say 1 3/4 x 1/4, then hand forge it from there.
  10. Hope you are well Alan, all good in damp south Manchester! - i'm still not back to making as much as I should, but getting the odd bit of making time when the stars align! Easy to forget the things we do like soaking, if you do it without thinking about it! Wrought over high carbon is not an easy mix at the best of times as they do like to pull in different directions as they cool if they dont get a few mins to get to know each other in the forge
  11. as an addition, and I am probably teaching you all to suck eggs..... but i've found soaking the weld after setting it makes all the difference to it holding together without delaminating for further operations like drawing out. Set the weld solidly, put it back in the forge at a good welding heat for 4 or 5 mins before you think about hitting it again. (back when I used to be allowed to smoke, it was a smoke and a bit it just sat there in the forge!) I twigged how much stronger 'soaking the weld' made it when playing with mosaic feather patterns. No soak = failure. Soak = happy days forging against the welds.
  12. That looks like a hard way of doing it! I'm not sure I could get that to stick clean in a gas forge without a big brutal power hammer. More power to your elbow for trying! If you are going again, i've had good success stacking up a clean 3 layers, say 5/16" cladding - 1/4" core - 5/16" cladding. You loose cladding to scale so it all balances out by the time you are at blade profile! If you try with any thinner stock than this you cant really put enough reduction into the stock to ensure the welds.
  13. I do quite a lot of wrought iron 'san mai' for my chefs knives. I cant recall how to upload pictures, but you can see examples on my instagram account ' @non_jic ' I forge very (very!) close to finished dimensions, down to a couple of mm, or less at the edge. This gives just a 'wipe' of core steel showing. I heat treat before grinding in the bevels (the profile is tidied up on a belt grinder before heat treatment) There are a few things I have found I need to do to be successful for a straight and true blade forging this close to finish - any warps or twists in heat treatment and the blade is junk. -If the bevels are not forged in evenly it will warp in heat treatment. -After hot forging I perform a full anneal. -After anneal I quite aggressively cold forge the blade to improve the surface condition - you can spend as long as it takes to make it look like a finished blade cold forging! -After cold forging, I Normalise the blade at least 3 times, reducing the temperature slightly each cycle. I hot stamp my makers mark on the 1st normalising heat. -The blade will warp a bit on each normalisation, and may need to be tweaked back true (cold) before the next cycle. Eventually it will 'settle down' and stay true. -Quench from an accurate temperature, into a commercial quench oil. Im sure there are quicker ways of doing it than my procedure, but I have got good consistency now and hardly ever 'burst' a spine etc! Forging this close to finish minimises the grinding time, but you need to go very slow with the grinding to make sure the core stays in the middle, its very easy to push it all off to one side. I often have to 'cheat' and reduce the depth of the blade by a couple of mm, and regrind the bevels in so the core is centred.
  14. Nice work, I built the same vertical HT forge about 10 years ago and never solved the temp gradient problem, so side lined it. I still have it and will probably make a long forge out of it when I get the rolling mill re-built.
  15. Would the outer faces of your blade not just be 1095 though, so you would mask quite a bit of the interesting stuff with mono-steel?
  16. good effort to take it as far as you have, but I think you know the answer! It looks too thin and wobbly to my eye. Ask yourself if you would be happy to see it again in a few years with your name on it? Even starting with thin stock, like you have, the tang transition is better 'bumped up' in forging to .160 / .200" where it enters the handle.
  17. go for it! Ive not done that much twisted patternweld, but if it makes a creak noise stop and re-heat!
  18. That may well be an option going forward! - Ive had people asking for power packs without the press as well Re the tonnage calc above, in Europe we work on 2240 lbs to a ton, so the Coal is sub 8 metric tons. Ive got some nice photos of the Massey '12' first batch in work, I've put them on instagram (@non_jic) - Ill post them up here soon. Im too tired to remember how to do it now! wife has the covid so cant do the school runs etc, so Im doing Daddying from shit o'clock in the morning - work for a full shift, then daddying to fall asleep time. grrrrrr
  19. I jump as many grits as possible. I regard each successive grit as only removing the 'ridges' from the previous one, not grinding 'virgin' steel, just knocking the ridges off. I dont see the point in doing this progressively. I don't get on with 24g belts, but never tried a quality one, on a suitable machine. 36g ceramics sometimes. I generally go 60 / 120 on the belt grinder. Its only a couple of passes at 120 to move the ridges from the 60 grit. All the work is done with the coarse belt. I then hand sand (or use a wet stone grinding wheel, but that's not relevant to this conversation!) A 120 grit 'hand sand' is a totally different finish to a 120 machine belt finish. The trick to efficiency for me is getting it 'true' and accurate with the coarse belt, everything else is a finishing operation, 120 machine grit is a couple of passes, and if your accurate, hand sanding takes no time at all. (ie, not chasing a wobble out of it for hours hand sanding)
  20. Knives look great (beautiful) - I'm in the camp that the edges are probably too flat for general purpose board work on 2 of them. (chefs are fussy buggers!) I played around with lots of edge profiles, and the ones that seem to work best are similar to all the popular and well regarded Japanese and European blade shapes (production and custom, they are similar). My opinion is they evolved over hundreds of years to that shape, as that's the shape they work best.
  21. I would 'buy and try' - it looks good to my (virtually) untrained eye. It can always be sold again, and you are only out the shipping!
  22. As has been mentioned, a hammer like that needs to be about 300 bpm. You have no real mass in the ram, so need to get some velocity into it to get forging energy. Spring rate is wrong, among lots of other things, but get it wound up to a decent speed, then address the other issues as they will make themselves known.
  23. thanks Alan! - if you push hard enough it will start to move eventually!
  24. I'm working on these two machines at the moment! they are just so pretty I thought they should get their own thread! The 2 cwt is my personal hammer, now rebuilt after the fire. The 1 cwt is off to a customer. In the UK both of these machines are regarded as 'Rolls Royce' Not often you see them side by side in nice condition They are both ready for testing next week. Busy busy!
  25. kind of agree (but disagree ) If they are going to be regularly used, use a bit of 'good stuff' for the dies if you can! You will get deformation, and scale is very abrasive. They will end up looking like a dog chewed them, after a while, if they are soft. Beauty of a press is you can get away with sub optimal dies for a lot longer than you will with a power hammer though!
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