What needle do I need for machine embroidery?

An embroidery needle, typically 75/11, with a larger eye and a deeper front groove than a universal so the thread is protected as it runs at speed.

Why not a universal. Embroidery pushes thread through the eye thousands of times per minute and reverses direction constantly. A universal eye is smaller and the groove shallower, so the thread abrades and shreds. Most thread breakage on an embroidery machine is a needle problem before it is anything else.

Sizes. 75/11 is the general default. 90/14 for heavier fabric, canvas or dense designs. 65/9 or 70/10 for fine fabric and small lettering, with a lighter thread.

Point type by fabric. A sharp or standard embroidery point on woven fabric. A ballpoint embroidery needle on knits, T-shirts and anything jersey, so it slips between loops rather than cutting them — cut loops on a knit become holes after a few washes. A metallic needle, with an elongated eye and specialist coating, for metallic thread.

Change it often. Embroidery blunts needles far faster than sewing. Every design or two on dense work, or roughly every eight hours of stitching, is a reasonable habit. A needle that has stitched one large dense design is not fresh.

Signs it is due. Thread breaks, shredding, skipped stitches, a punching noise, or small holes appearing round the stitching.

Fit it fully home with the flat of the shank the correct way round, and tighten the clamp properly — a needle sitting slightly low causes skipped stitches that look like a timing fault.