Vishvakarma tvaShTA bRhaspatiH

Source: TW

By the late vedic period, as indicated by the uttaranArAyaNa, vishvakarman was seen as a name of tvaShTR^i. This name superseded tvaShTR^i in the itihAsa-purANa where we encounter vishvakarman more commonly as the maker of the vajra.

bRhaspati or tvaShTR

However, from RV 10.81 and AV we get a hint that vishvakarman was originally applied to a similarly demiurgic manifestation of bR^ihaspati, especially in his manifestation as vAchas pati.

In early vedic tradition it appears that there were parallel traditions of demiurgic function featuring either bR^ihaspati and tvaShTR^i.

prajApati

In the later vedic tradition prajApati overran both their demiurgic roles. The paurANika brahman was an ectype of prajApati but inherited iconographic elements of bR^ihaspati-viShvakarman.

tvaShTR smithy

In the itihAsa-purANa vishvakarman-tvaShTR^i was left with just his smithing (= engineering) roles.