Let me toss in a suggestion- a machinist degree only takes a couple of
years to earn, and there's a shortage of qualified people just about
everywhere from what I can see. It's not much like the old days,
either- the hardest part about the job is dealing with boredom when
you're running a long job. But, depending on your area, it generally
pays pretty well, especially compared to unskilled jobs- and often
presents a lot of opportunites for scrounging scrap material and
running parts you may need on the bosses' machines (if you get the ok
first, of course!)
There's a lot of math, but the schooling also involves a lot of
hands-on with machinery.
Yep. I was dealing with a seasonal layoff in the spring last year,
and I know exactly what you mean. Give me 70 hour work weeks over a
layoff or unemployment any day- it's all a matter of momentum, and
once you loose it, it's tough to get going again for anything, no
matter how simple.
I just finished a job for 10 holding springs for a certain make and
model power chair folding foot plate. The OEM ones are about 20 maybe
22-gauge and break within a few months, maybe because they're formed
with a beautiful stress riser built in. :)
I made these replacements of 16-gauge 1080, quenched and then drawn to a
nice blue tending toward the Dark Side (Advice from D. Vader, MFA) with
no cutouts to make stress risers.
So far I have tested the living heck out of them and they're holding up
well, none broke.
10 minutes work each makes a $20 solution to a $215 problem. (You can't
get just the springs. You have to replace the whole assembly, mounting
bracket and all.)
Each one uses up 2-1/16 inch by 1 inch piece of stock.
Cool one. :)
How would you compare your own heat treated springs to hardware
store music wire spring steel? :)
---------------------
What I want Chas to know is the spring broke and maybe he did cause
it if he chingered a scratch/dent into it where it broke. But a
spring "should;)" not break... it should be able to bend and stay
bent. If you take a striaght spring and fold it back on itself
-flat- then yeah... but that's outside of design perameters and
doesn't count. ;)
--------------------
My 1950 Win-94's two leaf springs had terrible rough-ground surfaces
and on top of that, the marks ran across the springs. :/
I filed and sanded all those marks out and thinned the loading port
enough where I could shove a shell into it with my bare-thumbs more
than once. ;)
Alvin in AZ
I couldn't. :)
These were flat stock 1-inch wide X 2-1/16 long, cut out of sheet and
bent 3/4 round on one end, 1/2-inch I.D. with a 9/32 hole drilled in the
other end.
We heated them over critical and quenched. Files only skated. then drew
them to dark blue. Tested by hitting one with a 3-pound hammer trying to
break it. Couldn't do that either so far. Hammer just bounced, hard.
Hammer was not the one used for forging, but the one used for beating
the Hell out of things. :)
Complex springs break pretty regularly. Shooters sometimes carried extra
mainsprings with them for flint/percussion locks; found as a 'furnished
part' in cased sets an so on. The three-leaved action spring for the Colt's
single action is the most common parts-failure for that design.
I was grinding the spring flat to the lockplate, by hand; polishing the
bearing surfaces and the 'visible' outside of the spring. I had to clamp the
spring to get it on and off the lockplate.
I probably over-clamped it; compressed it to failure. I had 'actioned' it a
*lot*, for the fitting (practicing the skill, not 'having' it)- so it was
probably a combination of stressing it- like the novice I was.
I *think* I hardened my 1095 properly- it couldn't be filed, anyhow.
I used cold water brine, and it seemed to work pretty well. I also
tossed about a half cup of dishsoap in there as well without knowing
exactly why, other than that was part of that "superquench" recipe.
Tempering is where I kind of screwed up.
Seemed like the important part from what I could gather was making
sure to normalize the part a few times before hardening- IIRC, the
reasoning behind that was to relieve the internal stresses so that it
does not crack in the quenchant.
http://www.panix.com/~alvinj/graphFig6-7.jpg
;)
(and Fig 7-1 Page 174 ;)
The lower normalizing temperature for 1035 is ~1560F.
It's now obvious as anything that a careful normalizing step (or
three) is about "grain refinement", huh? :)
You said you liked to learn from the old guys and me too(!) but
sometimes their explaination for the un-seen part of it, doesn't
match with an otherwise really dangged good idea! :)
I don't diminish their idea on such trivial ramblings.
"What to do" is more important for me to learn from them and it's
up-to-me to figure out "why" that procedure is a good idea. :)
Alvin in AZ
Worth asking the big boys, though- the place I got my kaowool wouldn't
sell anything less than a 100 sq ft roll. Luckily for me, since they
didn't sell it in lower quanities, they just *gave* me 16 sq ft. The
guy at the warehouse wouldn't even accept a tip.
Definitely not at high as it could be- I'm no expert, but I have
managed to freeze my 20 lb tank solid a couple of times. I put it in
a bucket of hot water before I start now, and that's better. Still
annoying, though- with any luck, I'll be able to scrounge up a 100#
tank soon. From what I gather, that's about the size a guy needs to
keep the tank from freezing.
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