Calculating compound angle for taper bore

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korndog
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Joined: Wed Oct 06, 2010 7:59 pm

Calculating compound angle for taper bore

Post by korndog » Sat Jan 15, 2011 4:23 pm

Say
I have been trying to find a calculator to do this online but have had no luck. I need to go from 30mm to 27mm over a 50.65mm length of tubing.
Any help would be appreciated.

KD

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GlennW
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Location: Florida

Re: Calculating compound angle for taper bore

Post by GlennW » Sat Jan 15, 2011 5:01 pm

How about a re-print from a previous question...
Glenn Wegman wrote:So,

75mm long
large end=12mm
small end=4mm

Large end - small end= diameter change. 12-4=8

Since the taper attachment only wants to know the half angle, divide that by 2. 8/2=4

The half angle change would be 4mm in 75mm.

The angle in decimal degrees would be found using: atan=(height/length) or atan=(4/75) which is atan .0533 which is 3.0528°

Now to convert decimal degrees to degrees, munutes, seconds:

3° is the degree, which leaves .0528° to be converted into minutes.

Multiply .0528 by 60. .0528 x 60= 3.168. Which 3 would be the minutes, so we now have 3° 3'.

Now multiple the remaining .168 by 60: .168 x 60= 10.08. Which 10 now becomes seconds, so we now have 3° 3' 10".


I'm pretty sure someone that knows something about trigonometry (definitely not me) can show a simpler way to do it, but that is one way to do it since you have a taper attachment and will most likely need to do it again!
Glenn

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Rick
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Re: Calculating compound angle for taper bore

Post by Rick » Sat Jan 15, 2011 5:09 pm

This is the angle per side or what to set the taper / compound to
Tan = rise/run 0r opposite/adjacent

Rise =(30-27)/2
run =50.65

tan (angle)= ((30-27)/2)/ 50.65


angle =atan (1.5/50.65)

ANGLE= 1.696 DEGREES
Rick

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korndog
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Joined: Wed Oct 06, 2010 7:59 pm

Re: Calculating compound angle for taper bore

Post by korndog » Sun Jan 16, 2011 12:00 am

Rick wrote:This is the angle per side or what to set the taper / compound to
Tan = rise/run 0r opposite/adjacent

Rise =(30-27)/2
run =50.65

tan (angle)= ((30-27)/2)/ 50.65


angle =atan (1.5/50.65)

ANGLE= 1.696 DEGREES
excellent post...Thank you. Simple, direct, educational.

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