Introduction: We have received several requests for information about the collets used on various Rivett lathes. The requested information has been of two sorts: data on collets not listed in any of the standard reference tables (Hardinge's "Total Work Holding", older versions of Machinery's "Handbook", Goodrich's "The Watchmakers Lathe", etc.) or for more detailed and specific information on listed collets, as might be needed to make correctly-sized solid arbors, for example. In an attempt to provide as much as possible of this information, we have "pooled" our collet collections to furnish examples of as many different collets as we could find. If any reader can provide additional data, particularly of the 3OS and 5OS collets, please contact either of us. For bore sizes for 0.300" (7.62mm) and Ideal watchmakers collets see here.
COLLET ID:
DIMENSION: |
1R |
2OS1 |
2NS or Ideal |
3OS
|
3NS |
4C |
4OS |
4NS |
4S or 7 Rivett |
5C |
5OS |
5NS |
6R |
shank diameter |
.314" |
.2995" |
.3245" |
.5884" |
.687" |
.950" |
.750" |
.826" |
.999" |
1.250" |
1.061” |
1.062" |
1.375" |
total length, less curved face |
1 5/16" |
1 1/4" |
1 17/32"2 |
2 5/32" |
2 7/8" |
3" |
2 25/32"3 |
3 1/2" |
3 1/4" |
3 9/32" |
3.50” |
4 1/4" |
4 15/16" |
head diameter |
.498" |
.491" |
.499" |
.846" |
.950" |
1.162" |
1.104" |
1.155" |
1.380" |
1.470" |
1.330” |
1.395" |
1.679" |
head length |
.212" |
1/4" |
5/16" |
0.416" |
3/8" |
9/16" |
7/16" |
5/8" |
11/16" |
17/32" |
|
9/16" |
27/32" |
head angle |
40 |
40 |
30 |
40 |
30 |
20 |
40 |
30 |
30 |
20 |
10 |
30 |
20 |
thread OD (major diameter) |
.266" |
.265"4 |
.322"5 |
.509" |
.648" |
.938" |
.656"6 |
.804"7 |
.981" |
1.237" |
.847 |
1.046"8 |
1.298" |
thread pitch (all RH) |
.625 mm (40.64 tpi) |
40 tpi |
40 tpi |
26 tpi |
20 tpi |
20 tpi |
20 tpi |
20 tpi |
20 tpi |
20 tpi |
18 tpi |
20 tpi |
20 tpi |
length of threads, inc. relief groove |
11/32" |
17/64" |
21/64" |
1/2" |
5/8" |
5/8" |
19/32" |
21/32" |
13/16" |
11/16" |
.715” |
3/4" |
3/4" |
dia. over 3 wires (wire size) |
.285" (.018") |
.277" (.018") |
.333" (.018") |
.5215" |
.658" (.029") |
.947" (.029") |
.669" (.029") |
.809" (.029") |
.987" (.029") |
1.246" (.029") |
|
1.058" (.029") |
1.310" (.029") |
back bore |
.194" |
.189" |
.240" |
.414" |
.513" |
.720" |
.500" |
.650" |
.781" |
1.000" |
|
.884" |
1.125" |
keyway width |
.077" |
.065" |
.064" |
.109" |
.156" |
.122" |
.155" |
.163" |
.158" |
.123" |
.160” |
.156" |
.154" |
keyway depth |
.042" |
.022" |
.030" |
.064" |
.062" |
.059" |
.054" |
.049" |
.048" |
.064" |
.076” |
.055" |
.088" |
keyway length (full, from end of collet, over threads) |
13/16" |
11/16" |
3/4" |
1.085" |
1 7/16" |
1 5/8" |
1 19/32" |
1 11/16" |
1 3/4" |
1 3/8" |
1.35” |
2 3/16" |
1 3/4" |
example measured |
Rivett #18 |
Rivett #19 |
Rivett #18 |
Rivett 1/2" |
Rivett 9/16" |
Hardinge 15/64" |
Rivett 11/64" |
Rivett 17/32" |
Rivett 11/16" |
Hardinge 15/32" |
Rivett 9/16” |
Rivett 3/4" |
Rivett 19/32" |
NOTES:
1 Goodrich's designation: Rivett No. 1
2 Hardinge gives 1 9/16"
3 Goodrich gives 2 3/4"
4 Hardinge gives .263"
5 Hardinge gives .318"
6 Goodrich gives .665", Hardinge gives .660"
7 Hardinge gives .800"
8 Hardinge gives 1.050"