sherrirene

I recently bought an used Mega Quilter from an woman who had misplaced the asseorry box she had one bobbin on the bobbin winder and one with thread in the bobbin case I ran out thread in bobbin so when I took it out I found out that this metal and one is plastic I spent nearly one hour trying to wind bobbin kept getting caught up the first one wound very lose and the other one went down under bobbin spool Can anyone give me advise on which the correct bobbin for machine and what did I do wrong when filling any other information on is machine is great. I currently have an stand alone machine, I have a chance to buy an used Insprfra frame it is out of town and I can not see out before i buy the woman that will buy will meet me half way deliver is there anything should check on before buying? any information would be helpful what are the pro and cons thanks