Metalic thread problem-Help

You can try spraying the cone of thread with spray silicone. That can help the sewing. Also make sure your thread is not too old and brittle. I have never used Marathon metallic so cannot advise on whether is good or not, but don't have an issue with Madeira metallic threads and we use them a lot..

Couple things to try-
Put the thread farthest to the back on your thread stand. Like no. 15 needle. This helps to unkink the thread before it goes through the needle.

another way to help get the kinks out is to run the thread through a styro coffee cup or packing peanut just above the cone.

I use Madeira and never have problems.

As I understand it, (help me out if I am wrong), Metallic thread is usually made with Mylar chips. Mylar is the same thing they make those metallic looking balloons with. Grip the thread between your pointy finger and thumb and pull the thread and you can feel the chips.

You may have two separate effects interacting with the tension.
1. The larger chips causes more tension in some parts of the thread path because of the larger particles. example.... Butterfly clips. (Think playing cards in bicycle spokes) At the same time the plastic slides through some areas of the thread path easier. Example... under the tension disk where the thread holds the plates apart.

2. Because of the way the thread is made the strands of fiber holding the thread together may stretch under tension. Hold a piece of the thread about a foot apart and if you pull it it may stretch another 3 to 6 inches. The poorer quality thread will stretch more.

How to solve the issue...
1. Some metallic thread stretches so much you may not be able to adjust it out.
2. Loosen the upper tension a lot... I have even bypassed the per-tensioner at the top of the machine to get it to sew out.
3. Metallic thread has the tendency to knot up and kink. This is because of the rougher thread causes friction on itself and knots up. That is probably why Robert has had success with the silicone spray and EMBThtreads has had success with the Styrofoam.
You may want to try the plastic sleeves that some EMB supply companies offer. They hold the thread on the spools and keeps them from tangling.