There are different styles of needles for different styles of sewing machines.There are needles for standard, straight stitch sewing machines, and there are different needles for walking foot sewing machines.
For example, there are specific needles for the Juki DDL-8700, and then there are specific needles for the Juki DU-1181N.
Juki DDL-8700 Needles
The needles for the Juki DDL-8700 are the 16x257 in Groz-Beckert or 16x231 in Schmetz.
These needles may also be referred to as DBx1.
These needles will also fit the other Juki DDL models: 8100e, 8300, 8500 and 5550.
Purchase 16x257 needles Here
Juki DU-1181N Needles
The needles for the Juki DU-1181N are the 135x17 in Groz-Beckert and in Schmetz.
135x17 needles may also be known as DPx17 needles.
These needles will also fit the Juki DNU-1541S, Juki LU-1508N, THOR GC1541S, THOR RE-0303, Seiko STH-8BLD-3 and the Consew 206RB-5.
Purchase 135x17 needles Here
Leather Needles for the Juki DU-1181N
There are also leather needles that will fit the DU-1181N and the Juki DNU-1541S.
The leather needles are the 135x16. The number style is the same for Groz-Beckert and Schmetz.
These needles may also be listed as DPx16.
Purchase 135x16 needles Here
Leather Needles vs. Multi-Purpose Needles
The 135x16 needles are ideal for leather because they have a finer point, or as some say a "diamond point".
Therefore, the needle makes a smaller hole go through the leather.
The 135x17 needles can be used to sew leather, but they will make a larger hole in the leather.
135x17 needles are multi-purpose needles and can be used to sew the following applications:
While the 135x17 needles and the 135x16 needles can be used on walking foot sewing machines, such as the Juki DU-1181N and the DNU-1541S, those needles cannot be used on the Juki DDL-8700 or other standard, straight stitch, single needle machines.
135x16 are ideal for sewing leather, while the 135x17 can be used to sew all of ther medium to heavyweight applications.
The 16x257 or 16x231 needles can be used on single needle, straight stitch machines such as Juki's DDL series, but they cannot be used on walking foot sewing machines.