Jerry E. Howell
3980 Becket Drive - Colorado Springs -
Colorado 80906 - USA
(World Wide Supplier of Quality Model Project
Plans & Kits Since 1992)
Gear Cutting Without Index Plates
Do accurate gear cutting (or other circle dividing) up to 100
teeth (or divisions) on your rotary table without use of expensive
index plates.
(For the folks who do not have computers to do the calculations!)
Tables of direct dial settings calculated
to 18 decimal places and are accurate to 1 second of arc, which
is only 1/3600th degree! There are no cumulative errors as you
cut gears or divide circles. You could calculate these yourself,
but for just a 26 tooth gear you will have to make 78 calculations
and hope that they are all correct! Degrees, minutes and seconds
are needed for each tooth. If your rotary table dial doesn't include
seconds, just round them to the nearest 1/4 or 1/2 degree.
As an example, here are the dial settings from the table to cut
a 26 tooth gear. Would you want to use a calculator to do this?
| Deg. |
Min. |
Sec. |
|
Deg. |
Min. |
Sec. |
|
Deg. |
Min. |
Sec. |
|
13 |
50 |
46 |
|
138 |
27 |
42 |
|
263 |
4 |
37 |
|
27 |
41 |
32 |
|
152 |
18 |
28 |
|
276 |
55 |
23 |
|
41 |
32 |
18 |
|
166 |
9 |
14 |
|
290 |
46 |
9 |
|
55 |
23 |
5 |
|
180 |
0 |
0 |
|
304 |
36 |
55 |
|
69 |
13 |
51 |
|
193 |
50 |
46 |
|
318 |
27 |
42 |
|
83 |
4 |
37 |
|
207 |
41 |
32 |
|
332 |
18 |
28 |
|
96 |
55 |
23 |
|
221 |
32 |
18 |
|
346 |
9 |
14 |
|
110 |
46 |
9 |
|
235 |
23 |
5 |
|
360 |
0 |
0 |
|
124 |
36 |
55 |
|
249 |
13 |
51 |
|
|
|
|
The tables include the direct dial settings
for every gear from 8 to 100 teeth, plus tables of gear pitch
diameters for 14 pitches in a range from 6 to 120. Also, there
are formulas and examples to calculate various other apects of
gears.
Gear Tables (25 pages) - $10.00
(Use the Project
Plans Order Form to place an order. Otherwise, see the
"How To Order" page)
© Copyright 1998 - 2008 by
Jerry E. Howell - All rights reserved