Question

It is desirable to have drafts or undercuts as much as possible in the mould cavity, to have greater strength of the castings.

(a) True

(b) False

I had been asked this question in semester exam.

The query is from Permanent Mould Casting in portion Special Casting Techniques of Casting-Forming-Welding I

Answer 1

The correct choice is (b) False

Easiest explanation: The mould cavity should be simple without any undesirable drafts or undercuts because these interfere with the ejection of the solidified castings and makes the casting weak and less durable. And care should be taken to see that progressive solidification occurs toward the riser, in the designing of permanent moulds.