Crankshaft Taper?

Jim

Beyond the edge is the unknown. Here be Dragons
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Anybody ever measure the taper angle of the crankshaft rotor end? I need to make and indexing tool. I could take one of my motors apart I suppose... but ... any of you ever measure one?
 
not quite the question you asked but lemme look in the bins I have some "apart" cranks, If I knew last week...............
 
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A related question: are the Woodruff keys to fit available anywhere? All Princess Auto had was an 12" length of key stock.
 
Here's what I came up with
Set up on the lathe trued to with in .001 measured at the midpoint of the runout.
.100" in 1.000" of travel. this is side or .200" diameter reduction over an inch
DSCN3570.JPG


semi related;
I Ohmed the rotor I pulled off to get lakeside's :whistle: woodruff key dimensions. a "looks good" late model rotor,
Cold about 28F 4.9 ohms
room temp 65F 5.5 ohms
Warmed on wood stove 130F 6.1 ohms
back outside for a while 39F 5.1 ohms

Man I really want to get a 2 axis DRO set up!
 
Thank you gentlemen for the info on the taper. I want to cut an internal taper but think I will need a smaller boring bar.
How does you use the jig Jim.
 
Been researching this taper conundrum.
Such an odd taper, different from tooling and propshaft standards.

Used gggGary's numbers from post #10.
RotorTaper.jpg


It shows a 10.8° included angle, 5.4° tooling angle.

plugged the .100 in 1.000 numbers in here http://www.carbidedepot.com/formulas-trigright.asp
sez the angle is 5.71

Ggggary, if you do it with arctan of (.97 - .76) / 1.11 , it'll be close to 5.4°.

I found varieties of motorcycle tapers, 5°, 6°, 7°, 7.5°, 8.5°.
This one comes close to the 1:5 standard, 11.42° included angle, 5.71° tooling angle.
Probably should double-check gggGary's measurements.

Then I came across some old references to accessory and pulley tapers,
calling out an old standard of 3:16.

That's 3/16" per inch, or 2.25" per foot.
The tooling setup would be 3/32" per inch, or 1.125" per foot.

Which works out to 10.76° included angle, 5.38° tooling angle.

It's so close that I'd hang my hat on it...
 
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2M to the rescue
RangerSilver.jpg

thanks!
the .100 in 1.00 was much more carefully arrived at, reset and remeasured a couple times, it agreed with the measured angle quite closely. the 1.11" with the 2 diameters were just handheld caliper pulls. :shrug: But i'm just a hacker, better lucky than skilled I guess.
 
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