There is a bit if confusion between hand tied hair extensions and machine-made hair extensions. With the popularity of the “Beaded Row” technique, many people think that sewing hair onto a row of beads is hand tied extensions. What makes beaded rows hand tied is by using “Hand-Tied” wefts. Machine made wefts can also be sewn onto beads in the same way. I guess you could call any sewn-on weft “Hand Tied” if you want because either weft is sewn on by hand.
At first, hand tied extensions have a weft that is typically 11”-12” wide. The hair is knotted by hand along with 2-3 threads to create a weft. It is typically thin and requires more than one weft to make a row of hair that has enough thickness for most clients (I usually glue 3 wefts together to make one row). The weft itself (sewn part) is very thin and hides well on clients with thinner hair. Hand tied extensions can be sewed onto beaded tracks or braids. Most hand tied wefts are about ½ oz in weight. Cutting hand tied wefts is not recommended unless they are well glued using Bond-A-Weave. Hand tied wefts are typically more expensive because if the high cost of labor to make them.
What's more, machine made wefts are made with a special sewing machine that connects all the hair into one long weft. Most Machine tied wefts are 3-4oz of hair and are one continuing weft. They can be cut to length without gluing. A machine-made weft is has double the hair thickness as a hand tied weft so using only 1 or 2 per row may be enough. The weft (sewn part) is thicker so it is not as easily hidden in fine hair. I recommend machine wefts for people with thick hair. Braided weaves typically use machine weft hair. Machine wefts typically cost less because they are less time consuming to make.
Finally, both hand tied and machine made wefts can work beautifully sewn onto beaded track. I recommend using silicone lined micro rings for your beads. Large or X-lg sizes are best in my opinion. They are completely hidden by the weft and the larger sizes give you more to sew onto.