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Alan Longmire

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Posts posted by Alan Longmire

  1. 21 minutes ago, Pieter-Paul Derks said:

    At my recent trip to the US

     

    What did you think?  Feel free to start a separate thread if you want to share your experiences/impressions, and feel free to not say anything. I'm just curious. B)

     

     

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  2. Drilling problems are usually due to improper post-forging heat treatment and/or drilling technique.

     

    How are you normalizing/stress relieving the damascus after forging, and what alloys are you using?  If there's any 5160 or 01 in there you'll need to do a subcritical anneal, aka overtempering.  Alloys with chromium, molybdenum, or tungsten tend to air harden a bit, which means the usual carbon steel normalizing process of heating above critical and cooling in still air doesn't soften them enough to drill.  To do that you need to heat it up to a low red, below critical but way too hot for tempering, and then air cool.  This will solve most problems with ornery non-stainless steel.

     

    On bits: I like Irwin cobalt bits (I think they're M42 HSS?).  They're hard enough to drill tough steel, but not as brittle as solid carbide.  If you use a lot of one particular size, go to an industrial supply place like MSC and order a dozen of the same size, in cobalt, in "screw machine" length.  These are shorter than standard bits, which translates to more rigid, which equals less breakage and staying sharp longer.

     

    On technique: Always use lube of some sort when drilling steel.  Water, Windex, oil, spit, whatever.  It will help.  Do not step-drill.  Start with the size you need and drill it in a single press. If the drill isn't making chips it's just dulling itself and making a hard spot in the steel. Don't get too worried about rpm. Modern bits can take fast speeds and high pressures. I do holes from 1/16" up to 1/4" with the drill press running at about 1500 rpm, the middle step of the step pulleys.  Those old speed-feed tables are useful for plain carbon or M2 HSS bits, but not as relevant with the newer stuff. 

     

    Natural gas forges:

     

    They exist.  You'll need a blown burner, though. House pressure (11" water column, 0.4 psi) isn't enough to run a venturi to forging temperatures.  a 1/4" gas line dumping straight into the mixing tube with no regulator is best, but since house gas has to pass inspection you probably can't get away with that.  A potter friend of mine had the gas company put in a high pressure line to run venturi burners in his kiln, because that's the only way they'd allow him to do so in city limits.  This was not a fast or cheap process.  

     

    Since codes and insurance in this country will insist a natural gas appliance that is hooked to the municipal lines has to be UL listed, that leaves only the giant Johnson trench forges.  These are designed for heating up a few dozen jackhammer bits at a time and are terrible gas hogs and all but useless for bladesmithing, but you can find them cheap.  

     

    Member Chris Price figured out how to run a ribbon burner on city gas, IIRC. He doesn't hang out much anymore, but you might ask him.  Geoff Keyes runs his propane forges off a big whole-house tank, which might be another option for you.  Certainly cheaper and faster than getting an exception from the gas company.  You still need refills, but the truck comes to you.

     

    I look forward to everyone else's input on this!  I love to be wrong about things, that's how I learn new stuff...:lol:

    • Like 1
  3. Jim Austen uses a drawplate (much cheaper than a rolling mill!) and draws his silver to size.  At his 2013 hammer-in he had a bunch of guys doing it for him.  It was fun to watch, especially since the guys didn't realize they could stop at a few feet of wire. At one point they had it stretched about 40 feet, from the back of the shop out to the street. 

     

    Anneal first, use lube on the drawplate, and anneal after every pull.  

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  4. I love Wyoming.  Laramie is cool, as are most small college towns.  Thermopolis is a groovy hot springs town, Cody is home to a great museum (and amateur rodeo), Jackson is too expensive and full of tourists and rich people, the scenery is magnificent and changes on a regular basis. Everything from alpine to high plains, with badlands and canyons for good measure.

     

    Cons: Everything is at least three hours from everything else and there is no public transportation except for buses in Cheyanne and Laramie.  Also you have northern midcontinental weather, i.e. HOT summers and COLD winters with serious snow. Like, can't leave the house for weeks snow.  

     

    If I were moving to the western US I'd think about northern New Mexico for the better artistic community and excellent scenery.  If I were moving to the eastern US I'd think about western North Carolina.  There's a huge artistic community there (just over the mountain from me) and land isn't too terribly expensive compared to some places, unless you want to be in Asheville, in which case good luck.  Bakersville, Spruce Pine, Black Mountain,  Waynesville, or Silva  would be ideal for what you're thinking.  

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  5. I don't have time for a close deadline, personally.  Maybe if y'all decide to have the deadline around December 20?  I still may not have time to make something, but it's a thought...  Or even New Year's Day. That way shipping wouldn't be as hectic.

  6. It's just practice.  Let up on the pressure as you reach the end of the fuller, and the cutter rises out of the groove.  Hard to explain, but you can feel it as it happens. It's not a lot of letup, just enough for the cutter to rise.

    • Like 1
  7. If I were in your position, I'd go with the Grizzly. If that had been on the market 20 years ago I'd have bought it in a heartbeat!  

     

    The only cons I see are the relatively low power and fact that the motor is open.  Low power you can deal with, just don't get ceramic belts and don't lean on it too hard. Once you've had it a while, see about making an adaptor plate to put a more powerful motor on. Just make sure the VFD can handle it.

     

    The open motor is why they burn out fast. Metal dust gets into the motor and shorts it out.  Something as simple as taping a double layer of cheesecloth over the air intake would solve that.  While you're at it, do that to the VFD if it's not sealed as well.  Those go POP! in a fairly spectacular way if they get metal dust inside.

     

    -Alan who's still running a step-pulley KMG basic chassis 2x72 from 2005 or so...

    • Like 1
  8. Never seen those, but they do look decent.  The best "cheap" forges and burners I've seen are on Amazon under the Mr. Volcano brand.  For $79 you get not only an excellent burner, but a whole stainless steel forge with all the fittings.  And no, they don't pay me to say that (although I'm open to offers!). The Vevor stuff is absolute rubbish.  

     

    And it is indeed the Forged in Fire effect.  Helpful in some ways, not so much in others!

    • Like 1
  9. Thanks to Dick for pointing me in this direction a couple of years ago.  I do it on the lathe with a milling attachment.  SLOW speed, about 60rpm, miniscule feed just like Dick said.  Slow and easy is key, especially since this setup on my lathe is about as far from rigid as doing it freehand. I do not move in the X axis, I set the radius of the cutter to change the length of the nick.  On 0.090" thick blades I find a 1.25" radius is about right.  Tried it at 1.5" and it was too long, any shorter and it risks cutting through the back of the blade.   That's embarrassing...

     

    20230311_162518.jpg

     

    I've since cut off the extra length on that cutter, it made it too hard to set up without hitting stuff.

    • Like 1
  10. When I was building black powder guns, I'd heat-blue the screw heads. Easy and remarkably durable, but only on small parts.  Polish the mild steel part, heat until it turns blue, oil quench to preserve.  Like Brian said, it's just a temper oxide color.  If you have an oven that maintains an even-enough heat it should do for larger parts.  Also like Brian said, it's greatly dependent on surface finish.  A rough finish tends to go darker than a highly polished surface at the same temperature, maybe due to the excess surface area getting more oxidized?  Don't know...  

    • Like 1
  11. 30 minutes ago, Matthew Bower said:

    Depending on how much propane you buy, amortizing the cost of a new cylinder over 10 years is likely to still be a better deal than paying the exchange program rates.  

     

    That remains a given.  :)  Exchange tanks are filled with 15 - 17lbs, never the full 20.  I'm fond of my 40lb, personally. 100lb tanks are bigger than I like to wrestle into my truck, especially when full.  

    • Like 1
  12. Metatarsal fragments from your foot injury?  :(

     

    Be careful degreasing if you use the strong peroxide. It can lead to a chalky surface if you overdo it.  It’ll be pure white, though!  

     

    If you do peroxide, get it at a beauty supply place.  They don't call it peroxide or label it by concentration, so here's the key: it's called clear developer, and 40 volume = 12%, 30 volume = 8%, 20 volume = 6%. The stuff from the drug store is 3%.  They also sell cream developer, which is great for hair, not so much for bone or ceramic. That's what I use it on. 18th century ceramics. They tend to soak up a lot of grease, oils, and coffee/tea stains. A month or two soaking in 40 volume peroxide and they're good as new.

     

    That's my other hobby. I have a cupboard full of 200 - 250 year old English ceramics accumulated over the last 35 years or so. Buy it cheap stained and filthy, bleach it clean and display!

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  13. Ron, maybe he wants to sell you a new tank?  The date is stamped on the collar, or on the shoulder for larger tanks.  

     

    I bought my 40lb tank in 2004, the guy at my old refill place put a recert sticker on it in 2014 since it still looks brand new.  That place no longer exists, and the next guy I took it to wouldn't fill it in March of this year. So I found a place that doesn't check closely. 

     

    When my 20lb grill tank went out of cert I just exchanged it and took the loss. The exchange place will either recertify it or scrap it.

     

    I know why they do it, and it makes sense for tanks that see hard use.  My gently treated indoor-only tanks should be treated differently, but oh, well.  The 40lb will make a nice forge when it gets decommissioned. 

    • Like 1
  14. 14 hours ago, Bob Ouellette said:

    Thanks for all the tips. I'm very wary of sending the bones through the mail on account that they are irreplaceable.

     

    Understandable.  As long as they're degreased and properly dry they will last a very long time (several hundred years) in the usual household environment.  Stabilization is just a nice bit of insurance in case of damp or desert-dry.  

    • Like 1
  15. It's ten years unless recertified, but yeah, it sucks.  It costs roughly the same to recertify an old tank as it does to buy a new one.  The trick is to find a refill place that doesn't care.

     

    What Carlos is talking about is the initial "purge" of a new tank.  New tanks are not empty, they're full of air at atmospheric pressure. If this is not purged during the first fill, it makes for assorted hard-to-pinpoint problems during use.  Like, sometimes it works, sometimes nothing happens, sometimes it runs intermittently, and so on.  If you buy a new tank, be sure the fill person opens the purge valve and leaves it open during the fill until propane vapor is screaming out of the purge valve.  This ensures you have no trapped air in the tank.  

    • Like 1
  16. You might be surprised.  As long as you keep the sandpaper on a hard backing board and be sure to cut in one direction only (don't rub back and forth, just one way) you can certainly lay perpendicular sanding lines if you're starting with a surface that's finished to an equal or higher grit to begin with.  It does take longer by hand, of course.

     

    I see no problem with machine grinding it, just be sure to keep things cool.  If you can slow down the grinder that's best, otherwise grind wet if possible.

  17. 11 hours ago, Bob Ouellette said:

    do you have any stabilization tips or preferred products you've used for stabilizing bone?

     

    Send it to K&G.  Home stabilizing with Cactus Juice is too iffy for relatively nonporous stuff.  

     

    10 hours ago, JPH said:

    that is what I do with my bovine ivory

     

    I was hoping you'd chime in!  Being the master of bone and all.

     

    Gazz: Ooh, I don't have that one.  I have the other big Untracht book, though.  Metal Techniques for Craftsmen, I think...

  18. Bone can indeed be stabilized like wood, and probably should be.  

     

    The main problem with fresh bone is degreasing it.  Whole bones are tough to do, slices are much easier.  A long gentle simmer in water treated with about 1 tablespoon of washing soda (sodium carbonate) per gallon is a good start. Do not boil it, they'll crack and splinter.  Let dry under very low heat, like a food dehydrator. Follow that with a few acetone rinses. Once no more grease comes out, stabilize ASAP.  

     

    I bet some hunters or other bone collectors may have better methods, that's just what I learned for preparing zooarchaeological specimens. I never prepped the human forensic cases, but we didn't boil or acetone them for Reasons, and they stayed greasy for years.  

    • Like 1
  19. Yep, that's a classic case of fraud. :angry:  Yet another small-timer who bit off more than they could chew and gave the rest of us a bad name.  I've seen that so many times since the rise of social media.  Some guy comes up with a great marketing scheme and spends all their time and effort on that rather than actual product, then loses their shirt when they realize they have to pay for this stuff somehow.  Then they up stakes and disappear, leaving honest would-be customers out of pocket.  Prior to Facebook and Instagram, that almost never happened.  Now it's more common than a success story. 

     

    But yeah, it's not really a show-and-tell.  I'll put it somewhere...  

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