I have an old Singer 29-4 tredle machine I'm getting going. I need some help on what I should use for a needle. I'm going to use this machine primarily for sheaths, so I'm gonna be running it at the limit of its ability! I've been trying to figure out how big of a needle, seem to be a lot of conflicting information. I've seen anywhere from 29-4 110 to 29-4 160 with a Chisel tip. I'm a noob to this stuff (obviously) and don't really know what I'm doing! Any help would be appreciated! Thanks in advance!