C. F. Keil and Franz Delitzsch on 1 Chronicles 29:5

1Ch 29:5 לזּהב לזּהב, for every golden thing, etc., cf. 1Ch 29:2. וּלכל־מלאכה, and in general for every work to be wrought by the hands of the artificer. וּמי, who then is willing (uw expressing it as the consequence). To fill one’s hand to the Lord, means to provide oneself with something which one brings to the Lord; see on Exo 32:29. The infinitive מלּאות occurs also in Exo 31:5 and Dan 9:4, and along with מלּא,   2Ch 13:9.