You almost have to post a photo. Many machines were manufactured by X company, but might have been sold under several different names. We might be able to identify the machine by sight or at least help you find a manual. We can probably figure out the threading if nothing else.
The easiest way for me to post a photo is use the "manage attachments" button below this screen or use the paperclip icon above this frame. The trick is to reduce the size of your photo to less than 2 Mb. I usually just leave it full size and reduce the dpi to 96, but most anything like that will work. Then, be sure to scroll over to the right to find the post button. The screen comes up at reduced size and you either have to enlarge to find that button or scroll over.
bkay