For this purpose it is immaterial whether the second article is sold or otherwise disposed of, or if sold, whether the sale is a taxable sale. Any article to which this paragraph (b) applies which would have been used in the manufacture or production of a second article, except for the fact that it was broken or rendered useless in the process of manufacturing or producing the second article, will be considered to have been used as a component part of the second article. This paragraph (b) does not apply to articles sold and used as provided in any of paragraphs (c) through (f) of this section.
For tax-paid tires used in further manufacture after December 31, 1983, see section 6416(b)(3)(A) and the regulations thereunder.
26 C.F.R. §48.6416(b)(3)-2