XT not catching bobbin thread

[Wishes]

Dear List,
In 2006 we bought a second machine being an XT, brand new from Melco. We have had issues with the needle not catching the bobbin thread. At that time there was a lot of discussion about a part that wasn't aligned correctly. Something about certain SN getting this part adjusted. Problem is that the problem comes and goes and of course when calling Melco it wasn't always having the problem. Someone in Idaho kept track and did something to solve this. I need to find out how to solve the problem and maybe what part to look into replacing. Anyone remember that far back. Thanks
Margaret

[The Embroidery Authority - OLD]

Margaret,
I wish I could help but I just don't remember anything of the sort. There are so many parts that all work in unison for the bobbin thread to be picked up by the top thread. It's hard to say which one was a problem that far back.

A good tech should be able to figure something like this out in a short period of time, that is, unless it's intermitent.

Are the eye's of your needles facing straight forward? Is your needlecase loose? Presserfoot all the way down?

Also, in the last three years, you might be a good candidate for an adjustment to your needle depths, needle centering, hook timing and even Z timing. ...Just some things to consider.

Ed

[Rod or Sharon]

Margaret,

Ed is right....it is kind of like the old saying .....The foot bone connected to the ankle bone, the ankle bone connected to the leg bone...etc...

There are a lot of moving parts that muct all work together to make it all work properly.

What you were referring specificly to was probably the "Selector". The adjustment of the stroke and position of the selector during it's firing sequence is critical to it's performance. The pushrods that move the knife & selector must not be bent or broken and the housings for these pushrods must be tight and securely fastened.

When everything is adjusted "right", then operator varibles can/may come into play. Ed mentioned some of them. The use of adhesive spray, bobbin tension and/or type, standard or auto acti-feed settings, style of tie-in----tie-off's, hooping, threadfeed roller lubrication and digitizing issues are some others that come to mind.

The best thing to do when dealing with the "trimmer" function, is to run the Melco Amtrim test pattern and document where the failures, if any, are...ie....which needle, etc. Use an 18cm hoop and three pieces of medium to heavy cut-a-way backing, hooped tightly...no tear-a-way backing allowed for these tests!! Presser foot down, speed at 1200spm, poly thread...no rayon allowed, bobbing tension set correctly, the trimmer assembly cleaned and lubricated properly....in short, you must eliminate the varibles involved to find which one(s) are causing the problem.

Rod Springer
Amaya Tech & Trainer

[The Embroidery Authority - OLD]

Margaret,
The reason Rod's referring to the part of the trimmer system, called the selector, is because if the bobbin isn't being caught by the selector correctly, then it will be trimmed too short. Once the tail of the bobbin is cut too short, it will be very difficult, if at all possible, for the top thread to "pick it up". Which I believe was your original problem.
Since we're talking about bobbins here, you could also experience a similar situation if your bobbin tension is too tight.

Have you made any progress since your original post???

Ed