Dimensions of the Pattern with Machining Allowance

When designing a pattern for casting, it is essential to consider the machining allowance. Machining allowance refers to the additional material added to the pattern dimensions to account for the removal of material during the machining process. In this case, a machining allowance of 1mm is considered on each surface.

Original Casting Dimensions
The original casting has dimensions of 100mm (length) x 150mm (width) x 80mm (height). These dimensions represent the final desired size of the casting, which will be achieved after machining. However, we need to adjust the pattern dimensions to account for the machining allowance.

Pattern Dimensions
To incorporate the machining allowance, we need to increase the dimensions of the pattern by the machining allowance value. Considering a 1mm machining allowance on each surface, we will add 2mm to each dimension (length, width, and height).

- Length: 100mm + 2mm (machining allowance) = 102mm
- Width: 150mm + 2mm (machining allowance) = 152mm
- Height: 80mm + 2mm (machining allowance) = 82mm

Therefore, the pattern dimensions will be 102mm (length) x 152mm (width) x 82mm (height).

Hole Diameter
In addition to the overall dimensions, we also need to consider any features on the casting. In this case, there is a hole with a diameter of 50mm. The hole will be machined after casting, so we don't need to account for any machining allowance specifically for the hole.

Final Pattern Dimensions
Taking into account the machining allowance and the hole diameter, the final pattern dimensions will be as follows:

- Length: 102mm
- Width: 152mm
- Height: 82mm

Summary
To design a pattern with machining allowance, we need to increase the dimensions of the original casting by the machining allowance value. In this case, a machining allowance of 1mm is considered on each surface. The hole diameter should also be taken into account. By incorporating the machining allowance and considering the hole diameter, the final pattern dimensions can be determined. In this case, the pattern will have dimensions of 102mm (length) x 152mm (width) x 82mm (height).