OK, got the Lathe, Tooling, and now I need "consumables"

Intheshop

Banned
Gary,think reloading books....yes,certain things change.But there's knowledge in them that belies the purchase price.Tool Steel Simplified is a "standard".
 

Pistolero

Well-Known Member
YES! My grad school prof in "Materials Selection" graduate engineering course had us all get a copy
of Tool Steels Simplified, and I have used it as reference since then about 43 years.

There are new alloys being developed, but mostly niche alloys to solve extreme problems.
I was working on a advanced Stirling Engine design for production years ago and wound up
talking to Inconel about possibly using one of their alloys in a difficult, high temp application,
with sensitization and stess corrosion cracking potential. They sent me samples of a brand
new alloy that they were producing and we were setting up to test it when the customer
abruptly went out of business, cancelling the project. Another example is the special Carpenter
steel used in the RedHawk cylinders, special, ultra strong stainless. Those kinds of edge of
the performance envelope stuff are new, but 98% or more has been around for decades
and decades.

Bill
 
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Gary

SE Kansas
It's on it's way as well as Machinery's Handbook, and Technology of machine tools.
Thanks fellas, I appreciate you helping me build a library.
 

Pistolero

Well-Known Member
Returning from an out of town consulting job, was near my metal supplier, so stopped to stock up.

misc tube scrap ( to make a proper S&W frame wrench) $1.75 from scrap bin
1 1/4" 1144 round, 2 ft, $15.54
1/2" round 4140, annealed 4ft, $11.68
3/16" round 1018 CR, 4 ft $ 0.80
9/16" round 1018 CR, 2 ft $ 3.68
1/2" aluminum 6061-T6, 4 ft $ 3.92
3/4" aluminum 6061-T6, 4 ft $8.92

total of a hair under $50 with tax. I think this is pretty fair $$ and it is nice to be able
to walk in and get what you want quickly. 1018 HR/CR, 1144, 12L14, 4140 ANN in stock.

That will make a lot of stuff for me, and I know exactly what I have, mark it all with
paint pen as soon as it hits the shop.

Next project will be a hand controlled axial tap/die holder. After watching my T&D maker friend
tap at 270 RPM with zero risk of breaking the tap.....had to have one. Knurled OD steel 1 1/4",
by 6-8" long. Bore and ream a 0.500" hole for 5" deep or so, one end. Drill other end to accept
a key type chuck (so it won't unscrew on reversing) mount, straight with setscrew is easiest but
knock yourself out cutting a JT2 or something if that suits your fancy. Center piece is a carefully
made piece about 7" long exactly .499 diam and polished. Mount the 1/2 rod in tailstock, slip
1 1/4" knurled piece over it, mount tap in the chuck. Spin up drilled workpiece and manually
feed in the tap. Your hand friction controls the torque on tap, if it sticks, it will spin if you
are holding it right. Once it bottoms, stop, then reverse the spindle while holding the knurled
driver again, back out tap. ZAP! tapped hole, at speed, no tap breakage. HAD to make one.
Will also make an alternate head to hold 1" dies, swap out the chuck with setscrew.

One comment on 6061-T6. Keith mentions 2024 and 7075, and all three machine like butter.
6061 in the most common heat treat of T6 (or T651) yields at 40,000 psi, ultimate is 45,000 psi. If you
pay extra for 2024, you can find T3 or T4, or T6 heat treats. T6 runs about 50,000 yield, T3/T4 maybe
a bit less in extruded, maybe 46,000, or maybe the same. So, about 15-25% stronger than 6061T6.
7075 gets you a bigger jump up, to 73Ksi yield, 83 Ksi ultimate. 7075 is about the strongest aluminum
alloy out there, and is used in forged form for AR15 uppers and lowers, with a milspec hard anodize to
give it wear resistance.

Another thing to keep in mind when choosing materials is whether droop or deflection is important in
your application. If you took a 1" round bar of steel and clamped it in a vise, then loaded it with a weight
a foot out at the end, and right next to it you did a 1" round aluminum bar, clamped and loaded identically, the aluminum
will deflect 3 times as much with the same load. Strength or alloy are not important (as long as you don't
over load it and get permanent deformation). So, 6061T6 is STRONGER than A36 mild steel, but will deflect
three times as much. A lot of times the deflections are small enough with either that it makes no difference,
wear, weight, ease of machining, etc. will lead your choice. But it is not well known that aluminum is 3 times
as flexible as steel. Said another way, 1/3 as stiff as steel.

Bill
 
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Gary

SE Kansas
I have some 5/8" round bar steel (unknown pedigree) but it cuts nicely with a hacksaw; and about 16" of brass tubing that's 3/16" thick walled. What I don't like about my 3 Jaw is the center isn't open enough to run the 5/8" through the spindle and into the chuck. 4" 4 Jaw is on it's way.
Thanks for all the info Bill.
 

Pistolero

Well-Known Member
Another thing to check is how much runout the three jaw has. I was absolutely SHOCKED
(in a good way) to find that my 3 jaw has 0.0003" runout! I bought a collet chuck and collets,
and find that I use them much less because the "miracle" three jaw makes it so easy.

My machinist friend was even surprised. Some times it is better to be lucky than good.
I hope your chuck shows up to be really accurate, too.

Bill
 

Gary

SE Kansas
Surprisingly, it runs fairly good. I don't have the indicator on it yet, + I have a 4" 4 jaw coming at the end of this week. I finally got the lathe mounted to a bench this afternoon and hope to setup the tooling (QCTP) tomorrow. Hankerin' to make some chips I am!!