I think there was some mention in Mas. Megillah that discussed the method of doing hagbah and the usage of a mitpachat ("kerchief / cloth") for handling and covering the Torah. From this idea, it seems that Sifrei Torah, originally, did not use atzei chayim (the wooden rollers to which the parchment is attached to.)
These days, I've seen Sifrei Torah attached to rollers or encased for Sephardim. Are there any communities / nuscha'ot that still use Sifrei Torah without the rollers?