dec 23, 2003: used .0135 for the .005 width factor for sbrog.nc
Dec 15, 2003: zero the z axis for the mill at -.001 to cut the right depth
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108 degree point  (when grinding set the protractor on 36 degrees to
set up the 5c spin fixuture).   Now place a 20 degree face on the cutter..   Use the surface grinding
wheel on the edge but even with the spindle rather than under the spindle

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grind cutter to a D shape first... Grind so D measures .064" (.0015 over half).
Next grind to point 108 degrees
Next grind face at 17.5 degrees... this will make a little stronger point than at 20 degrees
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With the point cutting .005" deep the width of cut is .0138" (with at 108 degree point)
Note: with a 106 degree point... the width is .0133

Inside diameters
.016 barrels: measure around .779" finish size is .780
.014 barrels: measure around .774" finish size is .776
gold barrels: measure around .770" finish size is .773

Outside diameters
.016 barrels: .811
.014 barrels: .803
gold barrels: .800

The average od of all barrels is .805"  
Circumference is 2.5289"

1 degree    equals 80 steps      (using the 72 tooth worm gear)
360 degrees equals 28800 steps

2.5289" is to 28800 steps
as 1" is to ?

cross multiply
2.5289   1"       
28800    11388.3506 steps

set steps per 1" unit on the y axis to 11388 steps
WHICH IS 11.388356 STEPS EVERY .001"

trad.dnc = traditional
sbrog.dnc = silver brog
mille.dnc =millennium
14kbrog.dnc =14k brog
10kbrog.dnc =10k brog

2.5289   .001"   
28800    11 S

_____________________
Method:

place barrel on mandral
expand mandrel with nylon mallet
stick a piece of scotch tape all the way around the center of the barrel
Get the lathe dog out of the way (unscrew and slide it back)
Place mandrel in fixture
slide the tail stock up and tighten holding screw
Make sure you don't get it too tight. (spin the mandral and feel the backlash in the worm gear to make sure it isn't too tight)
Use dial indicator on tape to check for high and lows.
Mark the spot on the barrel where you want the front of the barrel to be according to the indicator
remove tape
Place lathe dog in place and tighten (both screws)
jog the y axis so the mark you want to be front is straight up
zero y axis



after it finishes
Push esc and get out of the program
Get the lathedog out of the way (unscrew and slide it back)
remove mandrel
take barrel off 

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for 1/2" diameter airgraver bodies set the Y steps to 18335

++++++++++++++++++++++++++++++++++++++++++++
pulleys for maxnc spindle:
1 1 EA  6495K726  Timing Belt Pulley XL Series, For 1/4"&3/8" Belt WD, 2.27" OD, 36 Teeth $18.47
EA $18.47 today 
2 1 EA  6495K711  Timing Belt Pulley XL Series, For 1/4"& 3/8" Belt WD, .93" OD, 10 Teeth $6.91
EA $6.91 today 
3 1 EA  6484K421  Endless Rubber Timing Belt 1/5" Pitch, Trade #50XL, 5" Outer Circle, 3/8" WD $2.67
EA $2.67 today 


1 to 1
400 1.11111111
360 1

4 to 1 
1600 4.4444444444
360 1

4.8 to 1   (1920 / 400 = 4.8)
1920 5.3333333333
360 1

3.6 to 1
1440  4
360   1

4.5 to 1
1800  5
360   1

5.4 to 1
2160 6
360  1

4.4 to 1 
1760 4.8888888
360   1
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