As manufacturers and suppliers, we deal with small set screws (small grub screws, small allen screws), which were standardized by our company under the brand name DELscrew. It is the small slotted headless screw, also known as the grub screw.
The set screw is sometimes written as "set screw" or "set screws", but it is also written as "setscrew" or "setscrews". The hexagon socket set screw that we provide is also known as the hex set screw or hollow set screw.
The DEL standard is the set screws with a total length shorter than the JIS standard (B1117) for a slotted set screws. The DEL standard was originally provided by SAIDA Manufacturing Co. Ltd. Below, we will introduce the background of the establishment of the DEL standard and the Delscrew.
In 1988, there was a major change in the JIS standard (B1117) for slotted set screws.
The main changes are as follows.
I think that the aim was to integrate the JIS standard and the ISO standard, but as a result, the old standard and the new standard set screw came to be mixed and distributed in the market. Those who use the set screw that time was confused.
Click the "colored part in the table" below to display each standard table, figures, and photos.
Screw tip shape | slotted set screws | ||
---|---|---|---|
DEL standard free-cutting steel | DEL standard stainless steel | JIS standard B1117-1995 | |
flat point | M1x1.0- | M1x1.0- | M1x2.0- |
cone point | M1x1.0- | M1x1.0- | M1x2.0- |
oval point | M1x1.0- | DEL standard none | M1x2.0- |
cup point | Custom order | M1.6x2.0- | |
dog point | Custom order | M1.6x2.5- |
According to JIS standard B1117 for slotted set screws, there are five types of screw tips: flat point, cone point, dog point, cup point, and oval point.
However, by the tip shape of the set screw that we ordered, the three types of flat point, cone point, and oval point accounted for 96%.
For example, the shortest total length is 2 mm in the JIS standard slotted set screw, but there are times when you want a shorter total length. For the past 50 years or more, SAIDA Manufacturing Co. Ltd. has received orders for various slotted set screws and manufactured them, and we have been able to feel the situation in that area.
According to JIS standards, even thin set screws such as M1, M1.2, M1.4 and M1.6 have the shortest total length of 2 mm. However, as a user, there are many cases where you want to use a set screw with a total length shorter than 2 mm.
In such a case, the user himself draws a drawing of the set screw and places a special order, but there are very few factories around the world that accept such orders.
Even if you are lucky enough to find a factory that can accept your order, it may not always meet the quality, delivery date, and price desired by the user.
Before 2004, there was a mixture of set screws designed by each user, set screws based on old standards, and set screws based on new standards.
Therefore, we decided to standardize the small-diameter set screw independently, and announced it on the Japanese website as DELscrew in July 2004.
Our original DEL standard is a fusion of the old JIS standard (B1117-1980) and the new JIS standard (B1117-1988). The DEL standard includes the total length from 1.0mm to 1.8mm of M1 to M2.5 (M1, M1.2, M1.4, M1.6, M1.7, M2, M2.3, M2.5) . This range is in 0.1 mm increments, and this total length is not included in the JIS standard. This is our DELscrew.
You can check the quality of the set screw with a Free Sample. However, please note that we cannot provide free samples of hexagon socket set screws.
The JIS standard includes "Slotted set screws (B1117)" and "Hexagon socket set screws (B1177)" as headless set screws. By the way, the JIS standard for set screws with heads is "Square head set screws (B1118)".
There are three types of tip shape of the set screw, flat point, cone point, and oval point, which can cover more than 95% of the demand. Therefore, the tip shape of the DEL standard (Steel) is made into these three types.
The nominal screw diameter of the DEL standard (steel) is there are eight types:
M1, M1.2, M1.4, M1.6, M1.7, M2, M2.3, and M2.5.
M1.7 and M2.3 are old JIS standards and are not listed in the current JIS screw standard table, but they are still used in the market, so we added them to the DEL standard (steel).
The material of the steel is 2600S of AKIYAMA SEIKOU, a lead-containing free-cutting steel equivalent to JIS standard SUM24L, and the standard stock is galvanized. Other plating and surface quenching (carburizing and quenching, etc.) are performed at the request of the customer.
Since the material is free-cutting steel (SUM24L), there is not much strength. The strength classification of JIS is 14H.
In the DEL standard, the total length listed in the JIS standard has a total length tolerance of + 0 / -0.2 mm or + 0 / -0.3 mm. (Current JIS standard total length tolerance is ± 0.2mm or ± 0.3mm)
For the total length shorter than the JIS standard, the total length tolerance is ± 0.05 mm.
With build-to-order manufacturing, we can also process slotted set screws with a total length of less than 1 mm. (It can be manufactured if there are 2 threads on the outer diameter screw part)
There are two types of tip shapes for stainless steel slotted set screws: flat and cone.
The nominal screw diameter of the DEL standard (Stainless steel) is there are eight types:
M1, M1.2, M1.4, M1.6, M1.7, M2, M2.5, and M3.
M1.7 is old JIS standards and are not listed in the current JIS screw standard table, but they are still used in the market, so we added them to the DEL standard (Stainless steel).
The material of the stainless steel is ASK-3000FL of AKIYAMA SEIKOU, a lead-containing free-cutting steel equivalent to JIS standard SUS303. In addition, surface treatment is also applied upon request.
The ordered products is manufactured by ASK-3000S (no lead) of AKIYAMA SEIKOU, which is equivalent to SUS303.
In the DEL standard, the total length listed in the JIS standard has a total length tolerance of + 0 / -0.2 mm or + 0 / -0.3 mm. (Current JIS standard total length tolerance is ± 0.2mm or ± 0.3mm)
For the total length shorter than the JIS standard, the total length tolerance is ± 0.05 mm.
With build-to-order manufacturing, we can also process slotted set screws with a total length of less than 1 mm. (It can be manufactured if there are 2 threads on the outer diameter screw part)
The hole of small diameter hex socket set screws can all too easily crack when the screw is being tightened.
Our hex socket set screws are made of Ni-Cr-Mo Steel (JIS SNCM240). Furthermore, the manufacture is high-precision.
Click here for more information of Ni-Cr-Mo Steel.
Through heat treatment, we have made the hardness to be high on Rockwell Scale C (HRC50 - 53) as well as coferring high durability.
The hexagonal hole is as tough as you can handle, and if your hexagonal bar spanner gets stuck during overtightening because the handle snaps (see the diagram below), it can be removed by magnet, because the hexagonal hole of our hex socket set screws does not deform.
For rustproofing, our hex socket set screws are surface treated with a black oxide finish and then dried with a hot air vacuum dryer. These screws will thus be suitable for automated assembly because they need not be oiled; at the very least your assembly workers need not get oily hands.
Click the "colored part in the table" below to display each standard table, figures, and photos.
Screw tip shape | Hex socket Set Screw | |
---|---|---|
DEL Standards Ni-Cr-Mo Steel | JIS Standards B1177-2007 | |
Flat Point | M1.6x2.0- | M1.6x2.0- |
Cone Point | M2x2.0- | M1.6x2.0- |
Cup Point | M1.6x2.0- | M1.6x2.0- |
Dog Point | DEL Standards none | M1.6x2.0- |
Oval Point | DEL Standards none | JIS Standards none |
CC Point | M2x2.0- | JIS Standards none |
Knurled Cup Point | M3x3.0- | JIS Standards none |
JIS standard B1177 for hexagon socket set screws has four types of screw tip shapes: Flat Point, Cone Point, Cup Point, and Dog Point. There is no JIS standard for the Oval Point.
The DEL standard has five types of screw tip shapes:Flat Point, Cone Point, Cup Point, CC Point, and Knurled Cup Point.
There is no Dog Point in the DEL standard. Oval Point is on the slotted set screws made of steel.
CC Point and Knurled Cup Point are shapes devised in this industry.
CC Point are short for Cup & Cone Point.
The CC Point is as shown in the picture, and the dented tip and the pointed tip are combined, and it bites strongly into the other party.
The sharp part in the center of the CC point protrudes about 0.1 mm to 0.2 mm from the circumference of the dent. Therefore, as you tighten the screws, the pointed part of the tip will bite into the other party before the circumference of the dent.
The Knurled Cup Point is hard to loosen after it bites into the opponent.
M1.4 Hexagon cap nut Material : Nickel Silver |
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Photograph is in preparation |
M1.2 Hexagon cap nut Material : Nickel Silver |
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Photograph is in preparation |
Round nut M2xP0.25 Material : Brass |
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Photograph is in preparation |