Sforno on Exodus 36:6/ספורנו על שמות ל״ו:ו׳

1אל יעשו עוד מלאכה לתרומת הקדש, he did not proclaim that no more donations should be brought. But he did proclaim that no more work, such as spinning, weaving, etc, intended for materials used in the construction of the Tabernacle should be begun. Also timber which had been brought in the correct dimensions with the carved parts should not be brought anymore. Compare 35,24 which discusses the need of treatment of both skins and trees.