Thankyou for your detailed reply. By the tone of your reply I must have struck a "raw nerve".......I apologise.
Specifcally in responce to a couple of your points.....
Point (1) "First of all, you can not sew welt without a welt foot. If you try to do this, you will make a gigantic mess out of whatever you try to sew that requires welts. A welt foot for your machine will cost about $35.00 at most. Why would you destroy a hundred dollars worth of fabric to save $35.00, and try to do this without the proper equipment?"
I have discovered that this is not practical. I haven't investigated costs of a welt foot yet. Here in Australia as a "novice" I'm finding help thin on the ground as upholsterers are seeing me as a threat. I guess they don't want me to succeed.
Point (2)"The reason you had such bad luck with a project out of Taylor's book, (or the Taylor -Mangus book) is that it is explained so poorly. I have been sewing and upholstering for 34 years, and what they describe is to me, incomprehensible. In fact, none of what they show in their books is a complete description of anything. None of the projects they describe are ever followed through to completion. My opinion of their book (books) is that they are disjointed at best."
I will have to take your word for this.
Point (3)"Your problem is as follows: 1) For heaven's sake, put a new needle in your machine. The eye in the needle may be doing the damage to the thread you describe. "
Yep.....will do !.
Point (4) "The tension on your machine might not be set correctly. It may be sewing correct stitches in some instances , but the tension is set too tightly, both on the bobbin case and through the upper tension mechanism, or not fed through your machine properly. If the tension is set too tightly it can cause the problem you describe, especially with polyester thread. Or......the twist of your thread is incorrect for your machine. Thread comes with either a right twist or a left twist. If you use thread that is not compatible with your machine, it simply will not work."
In my defence here all I can say is the machine was setup to work with the thread. I have to "learn" all of this. Like you said, you've got 34 years under your belt and I haven't got 34 days under my belt yet !.
Referring to the "manual" shows an explanation of thread tensions and it appears to be OK. The machine was bought from the female machinist who had used it (the machine) for auto upholstery work, mostly door trims etc. from new. She bought the machine when the company closed up.
Point (5)" The needle bar is the shaft that holds the needle. It goes up and down with the needle, and could not have been damaged by the needle itself, because it holds the needle. What the needle passes through, in your case, is the inside part of the presser foot. "
Thankyou for explaining that one.
Point (6)"The "manual" you describe is the same for every machine out there. It is not intended to teach you how to sew, it assumes you already know how to operate an industrial sewing machine that cost you well over $1000 new, and tells you what you need to know to adjust the machine, not to operate it correctly. This is the perfect reason to buy a sewing machine from a trusted local dealer. Will it cost you more? Yes. Will it save you untold grief? Yes. Is it worth $150 to $200 to avoid all these problems? Yes. If you had bought this machine from a reputable local dealer, it would have been set up to sew perfectly from the git-go, and any questions you had would have been answered before you ruined your seat."
Thankyou for explaining that one. In my defence, I paid $700 for the machine.....a bargain in my opinion. Similar machines when they come available in my neck of the woods would be at least double that. A chinese knock-off sells new here in good ol' Australia @ arround $1900-$2500. Interstate in Melbourne or Sydney is no better, plus freight on top if I buy from there and I'm still in the same boat......no dealer support.
In closing I appreciate your detailed responce and I'll update with what I find etc.. I will "source" a welt foot at my earliest convenience and replace the needle as suggested.