I think what you asking is "what are the different weights for?". or "When do I use each weight?".
If so, the 60 weight is generally for use as the bobbin thread. Personal preferences apply, but I think most people use 40 weight for the needle. The 30 weight would be used when a heavier or thicker look is wanted, like for satin stitch.
But to get good results, you should try to find out what weight the embroidery design was made for and use that weight. If you use too light a weight for that design you will not get a good fill. If you use too heavy a weight for that design you may get distortion of the fabric / design or even a rough surface to your embroidery because the thread is too wide for the alloted space.
>> Can someone tell me what the difference in 30 wt thread, 60 wt thread and >40
>> wt thread are (yes I know they are different weights!) I have been using >40
>> wt for everything but would like to know the difference.
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