| |
Radii
The general tolerance is +/- 1/64”, although
if necessary we can reduce this to a span
of 0.005”. For best results and lowest costs,
allow a generous radius, and avoid sharp corners. |
 |
Straightness
& Flatness
Castings are mechanically straightened when
necessary.
Tolerances for flatness and straightness are
.003” to .005” TIR per linear inch and depend
on alloy and configuration of casting. |
| |
Roundness
The general linear tolerance of +/- .005”
applies to diameters. On larger tubular castings,
closer tolerances can be held through mechanical
straightening. |
| |
Holes
Tolerances for holes are as follows:
Up to .250” diameter +/- .003”
Up to .500” diameter +/- .004”
Over .500” diameter +/- .0005” per inch |
| |
The following table gives you the amount
of eccentricity you can expect in an investment
casting.
| Outside
Diameter |
Inside
Diameter |
TIR
Eccentricity |
| 1/4" |
1/4" |
.008 |
| 1" |
1/2" |
.010 |
| 1-1/2" |
3/4" |
.010 |
| 2" |
1" |
.016 |
|
| |
Angles
The angular tolerance should not be closer
than +/- 1/2 ”. |
