Good idea in a pinch! I was so tired of fighting cone thread on flimsy holders and make do jars and home made holders. They just don't feed correctly. I bought this holder and it's the best I've used. It will hold a cone upright perfectly with even feed and will hold convert to horizontal. I was surprised at the heft and quality of it, very well made.
http://www.superiorthreads.com/produ...-thread-stand/ Nancy Notions has them sometimes on sale.