Blame Mister Lurie

 CAUTION: there is brief mention of self-harm in this post

 I've been asked how I got into machining (please remember, I'm a bodger, not a real metal-worker at all.)

 There is no simple answer, but roughly: A) high school metal shop, B) a friend who was an aerospace mechanical engineer, C) another friend who was a tool & die maker with his own shop, and D) reading books.  More recently, also watching certain parties on YouTube.

 But it was Mr. Lurie, my shop teacher in high school, who really put the bee in my bonnet, even though I wouldn't actually pursue any metal working for a couple of decades later.

 The shop itself dated from the post-war 1950s, when a large percentage of our four year high school graduates were expected to go into vocational careers, rather than college.  I went through high school literally at the end of Peoria's metalworking industry, as Caterpillar pulled up stakes and move their manufacturing, assembly, and warehousing somewhere else.

 The votec shops in my high school were epic compared to what I can find online today.  We had a completist shop for woodworking, for metalworking, and for both auto and small engine repair.  These were not safe spaces if you clowned around.  I took half a semester of wood shop and weirdly I thought, graphic arts, as prerequisites to metal shop.  The machines in wood shop were more dangerous and frightening than those in metal shop.  Also, the graphics art class included learning how to do mechanical drawings, ta-daa!  That was immediately useful in metal shop from the start.

 So our metal shop was informed by the local labor market...

 We had a foundry for aluminum with a gas-fed muffle furnace, using big crucibles and two-part molds, green sand, parting powder, the whole bit.  The ingots we cast were cut into blanks, then turned into pulleys by senior students for their belt sander project. (I still have mine, I use it routinely.)

 We had all the welding things: gas, AC stick (SMAW), TIG (GTAW), and MIG (GMAW/FCAW), plus several heat-treating ovens.

 We had the usual rows of small South Bend lathes, and a handful of enormous WW-II government surplus machines, including: a gigantic drill press with a five or six inche wide leather belt, an engine lathe ten feet long with 18in or so chuck that was a production to mount or unmount because it weighed half a ton, a big turret lathe, one antique horizontal mill, one antique vertical mill, a Bridgeport no one was allowed to touch, a gigantic cast iron surface plate... and all the smaller supporting machines and tools.  A tool crib you had to sign tools out of, just like real world shops... it was brilliant.

 Mr. Lurie, the instructor, somehow had me and a handful of others picked out as being likely to succeed, and gave us extra tutelage.  Of course he had a safety story - and a film - for everything in the shop.  Colorful character, with boundless knowledge if you just asked questions and then listened.

 Hand craftsmanship was emphasized; one of our first projects was an "exhaust port cover" (for an engine). In the real world, if you banged one out, it wouldn't need to be pretty or precise.  But we had to read a mechanical drawing, make the part to the right dimensions and shape (with curves), and except for drilling the two holes, it was all made by filing and belt-sanding.  The point was not to obtain something useful, the point was to learn skills. 

 Then I decided computers were where I wanted to go, I joined the USAF, and forgot about metal working or machining or welding for about ten years.  But high school was definitely where it started.

 I redeveloped interests in mechanical design and metal fabrication when The Denver Mad Scientists Club, of which I was a founding member, came up with The Critter Crunch, the first true fighting  robots competition, which eventually inspired the ones you saw on TV.  Once I started hanging out in my friend's shops, and seeing the fabrication capabilities they had, my old metal working joy resurfaced, and I started thinking about collecting tools.

 It turns out tools are expensive, so that took a few decades, but I am mostly content with what I have, for now.  There are one or two machines (band saw, sheet metal machine) which I need but haven't got room for at my current location.  The only tools I'll be shopping for forever are tooling for the machines.  I've bought the accessories and tooling I needed, starting with the most basic things I would use the most often.  I don't buy tools I don't yet need, just "because it seems like it would be nice to have some day" - homie can't afford that. ;)

 When I'm down to "nothing I own will let me make that feature" then I start shopping for a new tool that will.

 It took years before I found a lathe I could afford, and despite that it's a clapped-out 1970s pile of Chinesium, I have made it do what I needed it to do, right down to holding less than a thousandth for things like shrink fits.

 It took years before my Bridgeport fell into my lap, and it was entirely because I'd developed a treasured friendship with a guy who owned a machine shop.  When he traded up, I got the old machine at a very good price.  It came with no tooling, not even a vise.

 I still don't have a lot of machine tooling; I have exactly what I've needed to do stuff I couldn't do otherwise, and nothing more.

 When it comes to hand tools, and assuming you have a job/income, I recommend budgeting $100 / month.  In a year you will have every hand tool you can use, then you can start saving up for a tool chest.  For me, a tool chest wasn't a big priority; for most of my life, I kept my most-used tools on a pegboard backboard of my workbench, with the remainder kept in a Craftsman (Kennedy) "machinist's chest" sitting on a wooden chest of drawers that smelled bad when it rained.  A "machinist's chest" is one with the funky shaped middle drawer which is sized to hold a copy of Machinery's Handbook.

 It wasn't until my mother died and I received a small cash inheritance that I finally bought a quite large, professional grade tool chest.  I think I've written up the path to my purchase choice but even if not, I'm planning to do a "ten year review" or however long it's been, so I'll revisit that stuff then.  I haven't done it because I really want to go to a Home Depot that has the Husky Industrial line in stock, to see if they still measure up.  They could have changed anything at all since I bought mine, for better or for worse.

 I was at peak performance before I got the fancy tool chest.  Doing citizen science, over-employed as usual, ball of stress.  Then one day I had a record-contending fever that confounded everyone from Denver Paramedics to the ER doc, and left me with some drain bwamage.  Suddenly I couldn't figure things out in my head any more.  I couldn't remember anything.  In short, I had become slow, whereas before I'd been well above-average.  I almost did not live through the period that came after.  My intellect was all I had, all I was.  I didn't have personality, I didn't have charm, I didn't have looks, I had BRAINS.  And then suddenly, my major self-identity was gone, along with my day job career.

 "Improvise, adapt, and overcome."
- an unofficial slogan of the USMC
inspired by Clint Eastwood's movie 'Heartbreak Ridge'

 Suddenly we  were very broke.  I sold all my pulsed power / science kit for a pittance to a liar in my extended family.  I couldn't see any future at all.  For a while, I intended to tidy up my life and then kill myself.  I was in a very bad way.  Fortunately, I got help.  I am in a less-bad way now, and probably forever more.

 A reasonable question I asked myself then was: "whither the shop?  If I don't need machine tools to fabricate advanced switches or other pulsed power parts, then what DO I need it for?"  For a while, I considered selling the remainder of the shop, and most of my tools.

 After some years, especially after I had to go work in retail (BRAINS) for a while before being forced to retire fore real but early, one of several answers came to light:

1) The rise of fascism.  If you believe serious civil unrest and/or government totalitarianism is on its way, metal-working shops can be handy, 'nuff said

2) It doesn't matter!  So long as you're doing something, anything, with your hands and your tools that you enjoy, it doesn't matter what you actually do, if you're not hurting anybody

"Do What Keepeth Thou from Wilting Shall Be the Loophole of The Law."
-- J.R. "Bob" Dobbs

 And that is where I am at now.  I putter.  I fiddle with my not-quite-banned 3D printer.  I make tools both large and small for the shop itself.  Once in a while, I fix something for the house or for a friend.  I don't have goals or interesting personal projects.  I am no longer able to do science or even much in the way of engineering or electronics.  I have CRS real bad.

 On the other hand: my hands don't shake unless I've had too much coffee that day.  I'm still articulate even if I sometimes can't remember a word.  My health is not terrible for my age; I will breathe hard on a hike these days, but I can still go on a hike- a short one.  At altitude, I mean, not in town where we're only a mile high.  I don't have hypertension, the diabeetus, CPD, or organ trouble.  If cancer wasn't a thing, I would live forever.

 And you know what?  At the end of the day, pointlessly puttering beats the roiling tar-muck out of drinking myself to death, as some of my brothers chose to do.

metal-urgy, the method of working with metals

 Before I start, know that metallurgy can be pursued by average people without any college degree, nor prior schooling in the subject!  There will be unfamiliar words at first, but you can figure it out if you try.

Right then, this guy's very thorough web site on knife metallurgy, holy wow:
 https://knifesteelnerds.com/2024/04/22/wootz-the-true-damascus-steel/

 Dunno if anyone else has a passing interest in knife-making; I only have a passing interest- no intention of actually doing it, but the metallurgy interests me.  The origins of steel, and the ancient Wootz process (Southern India, 400 BCE) also interest me, especially because quite subtle differences in chemical makeup, temperature control, and grain structure make the difference between pig iron and the "best" steels there are.

 I learned of the existence of Wootz steel by reading Neal Stephenson's "The Baroque Cycle", which is like eight thousand pages or something, but I absolutely love it because of all the fascinating "nerd history" and "emergence of scientific thinking" stuff which is er, rather the point.  Stepheneson is smarter than I am, and I don't say that lightly, LOL.

 ANYWAY, the above-linked site, videos, and book, appear to be the bee's knees when it comes to knife metallurgy.  The focus is on metallurgy not the mechanical process of knife-making.  I'm more about questions like, "why doesn't low carbon Chinese steel from the hardware store weld as nicely as low carbon steel from the scrap yard?" (spoilers: it's because Chinese export steel is hot garbage with massive inclusions throughout the material)

 The author drops many useful hints, like describing which metal features dictate "toughness" for example, or allow for fine grain structure at the cutting edge, and other attributes of steel and how they are informed by the metallurgy.  That was the most useful part of reading his site.

 One of the ways a budding metallurgist examines grain structure, which has a lot to say about overall steel "quality", is to cut, polish, and etch a sample, then look at it under a halfway-decent (digital camera type is fine) microscope- anything capable of 100X - 500X magnification.  (up to 1000X is even better, but unlikely to find.)  This is almost easier to do than describe, although the polishing part does require a few hours' time.  Looking at a monitor beats hell out of looking though an actual microscope.

 For steel, the etchant is frequently "2% Nital" (2% nitric acid in 98% ethanol.  Methanol can also be used but of course it is toxic.)  You can buy Nital solution premixed all over the web.  All metal etchants are selective etchants which increase contrast by etching one component of the steel more than others.  Specifically, Nital reveals the ferrite grain boundaries and cementite.  Other etchants will reveal other features better, but watch out, some of the etchants for stainless and superalloys - especially those containing hydrofluoric acid, such as Kalling's No.1 and No.1.  Look up the poisoning effects of HF acid just once, and you will definitely wear your PPE, or more likely, choose not to mess with it.

 Here is a good intro/summary for 'metallographic' etching:
https://www.buehler.com/blog/metallographic-etching/

Here is another:
https://www.metkon.com/metallographic-etching/#

 The following weighty tome is a general text on etchants vs. all metals plus the elements used in chip foundries.  It is primarily oriented around chip foundry etching needs, but it does cover just about every metal etchant known to man, and what the hey, it's free and takes no shelf space:

https://vector.umd.edu/images/links/Handbook_of_Metal_Etchants.pdf

 That is all for now.

EDIT, LATER: No it's not, LOL.

This is also educational on the basic grain structures of steel, short, easily digested: 

https://www.youtube.com/watch?v=0SIr2sBHxA4

it should not be possible to make these for $40.

 I am pondering the mill arbor (generally).

Clearly runout is bad, since runout at the arbor is going to be larger at the saw or gear cutter OD.
Well I can't measure any so I've got that going for me, which is nice.

 But-but-but, those pesky spacers!  In order to - again - not have our saw OD waving up and down, the spacer ends need to be ground flat and parallel with each other.

 On the other hand, I'm not sure concentricity to the arbor matters much at all.  These are part of a clamping mechanism.  Having a really close fit on the arbor would be nice, but the fit of the saw ID onto the arbor surely matters much more.  However, it very much looks like their OD was ground with all of them mounted on the arbor.  Not sure.

 All of them are keyed, but the last few won't pick up the key unless you put a thick one at the bottom.  The more of the arbor stub sticking out past the cutter, the harder life becomes.  Doesn't matter to me yet, as this saw is not keyed.  Set things up so that sawing tends to tighten the nut and you're golden.

 If there is a burr on the end of a spacer, it shows up dramatically on the saw OD.  Found the ringer by checking all of them on the plate one at a time.  My cost on this arbor is no longer $40 is what I'm saying.

If there is shmutz on the end of a spacer, it shows on the saw OD.

 When everything has been cleaned as if it were going into a chip foundry, checked on the plate, assembled with the care of a deep space probe, and reinserted into Igor (the mill), the saw runs perfectly true.  Simple!

 I have also proven I can make deep cuts with it in aluminum, despite the lack of dishing or tooth offset.  I calculate the RPM from standard SFM, then reduce it to 1/3 of that.  About 60-100 RPM seems okay.  60 is as low as the mill will go.  Feed very, very slowly.  Patience is the order of the day.  Knock on my wooden skull.

 I really ought to fix the power table feed soon. @_@

wishy-washy washers and headbutt nuts

 Number A:

 That big damn nut on the end of the arbor makes it hard to saw something clamped in the vice.  I was just barely able to do the cuts I needed on two sides, but now it seems I'll need to be very brave (I am not brave on setups, I am conservative, as I dislike it when work flies out of the machine and tools break) on the next several cuts.

 And my sharpie marks wore off so I've gone back to the bench to use layout dye and scribe the marks I need in that.

  OH WAIT, my layout dye is nearly dried out.  Can be partially reconstituted with ethanol, but only partiall - it also wants butyl acetate, which neither you nor I have on hand.

 OH WAIT, my scriber is dull and chipped (when did I drop it on the point?) so I'll just hop online and... I'll just hop online and... I say, what the galloping F, I can't buy a scriber without a magnet, and if I do, the tip isn't replaceable?  And literally nobody is selling a nice unit with a brass or wood handle... with a conical scribing point.  There is one nice brass and wood engraving pen... but it hold carbide engravers knives, not conical scribing points.  FML

 But hey, at least the runout on the arbor is less than I can measure, which is nice.  Also I need a tenths indicator, LOL.   Never enough tools.


Letter 2: 

 What in the seven hells is going on with these "precision" spacers on the arbor?!? Check this out:

 

 Maybe it's only the chamfers which are making that weirdness apparent - which, I dunno, were maybe hand-ground before sending them to heat treat?  Remind to take a file to one when I got back out, I bet they aren't even hard.  Grump.

"Progress was alright. Only it went on too long." - Thurber

  I am outraged, outraged I say, that the $4 Chinesium "slitting saw" I bought off of Amazon is not properly dished for cutting clearance like a $400 made in the USA unit is. This means it can't be used for its stated purpose, if you try you will have a very bad day. (spoilers: it'll break)

 This was not a succulent Chinese meal for me.  Is this democracy manifest?!?  $400 quality cannot be had for $4??  I shall write my congress-critter! 😂

 Meanwhile, the saw arbor that was promised for Saturday before the sale, is now promised for Monday after the sale.

 Findmall (a store on Amazon) does this a lot.  Some other stores on Amazon do not.  Don't give your money to stores that pull any sort of bait & switch on you.  Don't reward bad behavior.

tool pr0n

 For some time, I have wished I had a slitting saw + arbor for the mill.  Slotting saw?  (there is some debate over which is which - textbooks don't agree) 

 Anyway, I've wanted to cut keyways in a shaft for instance.  I've wanted to cut a thin slit in a clamp with a round hole.  I've wanted to make deep grooves.  Try making deep 1mm wide grooves with an end mill.  That's not happening.

 Also, the arbor can be used with gear cutters too.  And probably some milling cutters I'm not even aware of.

 And hey, if you've ever needed to make your own heat sink with thin fins, this is how you do that - stack a bunch of thin saws with spacers on the arbor. You'll need a power table feed and patience... and ideally a lot of emulsion coolant... so you won't catch me trying it any time soon.

 I've been eyeballing these for more than a year.  I chose 22mm over 1in kinda arbitrarily because when I shop for saw blades, I see more available with a 22mm hole vs. a 1in hole.

 Now, I find I'm making something which would be seventeen times easier (I measured) if I had the darned slitting saw.

 Did I evaluate other options? Yes! Option one was to cripple myself trying to do the same work badly, with a hand saw.  It would have taken days or weeks, including time for recovery in between.  This is not a hand saw job.  Option two would be a five thousand dollar band saw.  Which I haven't got room for even if some rich uncle gave me one.

 So I think I'm gonna pull the trigger on a cheap Chinesium sample and see how bad its runout is, since they don't specify runout until you get into the hundreds of dollars for non-Chinesium versions. Will it be useable?  We'll find out tomorrow.  It will certainly be returnable.

 It's well under $50 for the package which is ridiculously low compared to name brand, but even that is a bit of an ouch in the wallet.  I hate being retired, unemployed, and broke.

 Update: Hah! I can check the runout of the arbor tomorrow, but I won't get to play with the saw until Sunday.

 

 Random thought: this probably won't fit in my existing collets-n-arbors holder mounted to the side of the mill; it will probably stick out too far and hit the table.  Another item to go in a drawer and get scratched up because it's in a drawer with other steel items.  Offends my delicate sensibilities, it does.

 Honestly, this is all Inheritance Machining's fault, as he has helped me start caring again about the quality of my work.  It's not my fault I'm spending money, it's his.

issues, I haz 'em

Issue Numero Uno

I need to weld two steel straps together, maintaining squareness and dimensional alignment over a length of 28in.  The smaller of my regular welding magnets are too large.  I went looking for tiny welding magnets and discovered that most vendors attitude toward "mini", "small" etc is, "dimensions? why would you want to know that?"

 Found some that might serve, but I really don't feel like spending money on a maybe, and maybe the return will be a hassle and maybe it won't...

 The next-most-obvious solution is a custom made jig.  Okay, I'm used to making those anyway, and this one would be small.  How-some-ever: it's "nominally 1/8in" material (actually as small as .113) and the only 1/8in cutter I have is a fancy solid carbide cutter with... oh hey, is that an TiB2 or TiCN coating on it, specifically for aluminum?  Perfect.  Except I have sh*t luck with tiny cutters; I break them.  I need a power feed and more patience, but until I'm able to acquire either of those, I'll just have to go a lot slower (feed rate/CPT) than I am used to.  On the plus side, carbide cutters go crazy fast in aluminum.

 The jig would be a T-ish shaped hunk of random aluminum, with two intersecting .125 slots.  The idea is to tack one end, then back the fixture away down the material, as I put tacks and then stitches down.  This gauge will need a small relief on the insides of the corners, for the fixture to be able to slide over the weld beads.  If I can swing it, that relief will be the same curvature and dimension as the corner radius of the steel that needs to slide through this assembly.  So if the jig slides, the actual sliding part will too.

 I could avoid that entirely by drilling a bunch of holes or slots in one piece and welding from outside, but this is not as strong unless I go to great lengths.  That would make two parts very "expensive" in terms of time and effort.  So I am not doing it that way.

 The order of assembly allows me to weld the "caps" on and if necessary, grind or mill, the welds in the  inside corners of the two channels before sticking the sides on.  The sides get welded on from outside.  Gee, it sounds good on paper...

Issue Numero Dos

Ace / Hillman: Worst. Steel source. Evah.

 Don't buy steel from Hillman!  I know I already pointed out that Hillman are cheating you on steel thickness, but check this out;

 Today I found a rough spot that I could feel but not see, due to the strange surface finish their steel has.  I had just finished getting their thrice-damned label off with a putty knife and acetone, so I thought maybe it was some hardened label adhesive or the like.  So I ran it over the deburring wheel, when suddenly -->

 That is deep rust pitting.  This piece of steel laid around in the weather and got rusted as hell, then they broomed it (w/ wire brush, convolute wheel, etc) and hoped no one would notice.

 This might also explain the reduced (deceptive) thickness, if they have to do it a lot.  Fook China and Hillman both.

 Strongly recommend you don't build anything important with their stuff... such as outriggers?  Well, the outrigger housing is so over-designed, I could lose 1/3 of the thickness of all of the steel involved and it would still be safe.  I try to build stuff that does not break.

Issue Numero Tres

Are You Fookin' Kidding Me?

 This fookin' ferrule for rack handles!  That price is not for the handle, it's just for the little ferrule where the handle joins the panel.  I need eight more of them. 

 I am not bloody well going to make eight fiddly ferrules from scratch, tho I certainly could.  I don' wanna.  So I look online and got some serious sticker shock.  They aren't on eBay either (at the moment).  I'll keep looking around the interwebz and watching ebay.

 I am not paying two bucks each for a fancy washer that has zero labor in it, since it is made on an automatic screw machine.  JFC.   Keystone Hardware, via Digikey is "only" $2.51ea in black, silver is a little less...

Sofa King Wee Todd It

high performance brazing with your MIG welder

 
 So I was today years old when I discovered you can buy ERCuSi-A Silicon Bronze MIG wire in three popular sizes, and with this wire, you can A) MIG weld high performance silicon bronzes and B) MIG weld galvanized steel.  (Cough, they say.  I'd want a positive flow mask or a reall good exhaust fan)

 It is well-known enough that even Amazon carries it.  This would have come up if I had been able to continue with my pulsed power work.  The fast Marx trigger generator had a coaxial copper housing with a bronze flange at one end for closing the ground end and their joining needed to be robust both mechanically and electrically.  At the time I was thinking silver solder.  Never got the chance to finish that project. 

buying steel

Two things.

Thing One
I'm still struggling with the design and materials for the hoist cart's outriggers.

• they need to extend far enough out that some kind of stowing means is necessary,
  otherwise, I'll be destroying my shins against them constantly

• from a mechanical strength view, a sliding/telescoping mechanism looks better than
   something that swings around on a pivot, and it occupies less space

• telescoping tubing is hard to come by, you usually end up fabricating at least one of
   the two pieces, and that is exactly what I intend to do.

obviously the parts aren't aligned or fixtured

• I have rectangular tube I'd like to use which is perfect for the outrigger arms, except I cannot buy a ready-made outer tube / shell / housing with the right ID

  I bought a lot of steel to weld up my own housings to fit the those two tubes I have on hand, but one dimension, which appears on two long pieces, is too small by about 1/16in.  I'm goingto try to fill it in with weld anyway.  Then comes the adventure of cleaning up the interior enough that the tubes will actually slide into it.  >_> 

 I've been planning on making the 'H' beam first, so it can be welded from inside.  If I decide I don't want to do that, I could also drill a series of holes or mill slots in the wide bit, and weld the center web from outside. Clearance is set with thin (.015

 Anyway, here's Wonderwall a lashup of my general idea:

But I paid for .125 thick, Hillman!

Thing Two
 Be careful when buying steel from hardware stores. They cheat you on dimensions like thickness.

 ie; you pay for 1/8in thick material, but it's really .114 or even worse.

the offending vendor (found at Ace Hardware)

How thick will this stick be?  How thick will that stick be?  Astonishingly, there is variation in a single short stick.  Yes, I checked my measurements several times.  The measurements at left were AVERAGE, not the smallest on the sticks.  The smallest was around .112 on both which is just ridiculous.

 When I buy steel from the surplus yard, and have to blast rust and mill scale off of it, it's right. on. dimension. Hot rolled, cold rolled, doesn't matter.

When I buy clean steel from McMaster, it is either right on dimension, or a few thou over.

 HOW IS THIS STUFF TOO THIN, THEN??  This stuff comes out of a rolling mill, for Ghu's sake.  What could someone possibly do to add variation in thickness?  It would seem impossible, but calipers don't lie, and neither does a dial indicator on my surface plate.

WTAF, Hillman?!?

 Parts of this assembly can see up to1,200 lb strain, and if it breaks, people could get badly hurt.
I guess I'd better re--figure the complex box beam calcs I already did once like half a year ago, to see whether I need to buy all new steel (and then throw this Chinesium garbage through Hillman's office windows - the one in Boulder).  Grump.

 Hillman would try to throw their "overseas partner" (China) under the bus, to which I would respond, "Don't you perform incoming QC? Don't try to tell us this is a one-off."

 I've seen this at two different Ace Hardwares, but oddly, I can't find anyone else whinging about it on Reddit or YouTube.  Obviously it's a secret conspiracy against me, then. =^_^=

nailing a few of my theses to the workshop door

 Regarding bans on 3D printing (additive manufacturing) and licensing or permitting or inspection of machine shops (subtractive manufacturing):

1. Get a (proper) warrant.

2. You can take my tools over my cooling corpse.

That about covers everything, I think.

 I will not comply with the law, should such legal experiments become the law of the land.
I will not meekly obey, civilly or otherwise.

Everything or nothing. All of us or none.
One alone his lot can't better,
Choose the gun or the fetter.
Everything or nothing. All of us or none.
 
-- from Bertolt Brecht's "Svenborger Gedichte"