Plier material
Plier material
(OP)
Hello, I am looking to design some pliers with custom jaws and wondered what alloy is commonly used to make your garden-variety slip-joint pliers, and would it be easily machinable, and what kind of plating would I want to apply. Thanks for the help!





RE: Plier material
RE: Plier material
RE: Plier material
RE: Plier material
Higher quality ones are made from a low-alloy steel with a higher carbon content, so the jaws can be hardened through heat treatment.
As for plating, some are un-plated, others are chrome plated, some have an oxide coating or some other surface conversion coating (phosphate coating?). The coating is mostly for corrosion resistance and aesthetics.
Just using an low-alloy steel won't make a quality tool. Some very high-quality tools are made from stamped plain-carbon steel. The difference is in the design and quality control. The cost of the material is usually only important on large production runs.
rp
RE: Plier material
RE: Plier material
Maybe you can find existing pliers that meet your needs and just modify them by machining new jaws or perhaps welding extensions to the existing jaws. For a small number, this might be easier. You might have to anneal the jaws for machining (then re-harden) or use a very controlled welding process (to prevent cracking), but these problems can be fixed rather easily. This way, you can use someone else's engineering for the basic design (you know it works) and have fewer decisions to make.
rp
RE: Plier material
Utica brand pliers
1020 steel, hot forged (with decarburization), through hardened and tempered to 39 HRC (surface) then chromium electroplated.
Craftsman brand pliers
custom alloy steel (Cr-V), through hardened and tempered to 44 HRC (surface), no surface treatment.
Many small hand tools have been made/are made with 6150 Cr-V steel, which is widely available, so you don't have to buy 20-ton lots like Sears does.
RE: Plier material
RE: Plier material
Won't 1020 have a 'hard' time getting to 39 C even at the surface without some sort carburization?
guimba-
Watch out for soft coatings on your jaws, they will wear quick and may cause gripping issues.
RE: Plier material
I'm sure Cory will respond too, but the answer to your question is yes, 1020 has difficulty achieving any type of reasonable hardness (> 35 HRC) unless it is water quenched in thin sections (only several mm thick). For pliers, the surface transforms quickly, but the center, even if it is only 2 or 3 mm below the surface, will be 50% martensite or less, meaning lots of ferrite, pearlite, maybe some bainite.
RE: Plier material
My data was based on actual reverse engineering I did with my tools today. TVP provided the correct answer regarding hardenability problems.
RE: Plier material
KENAT,
Have you reminded yourself of FAQ731-376: Eng-Tips.com Forum Policies recently, or taken a look at posting policies: http://eng-tips.com/market.cfm?
RE: Plier material
The first two are pre 1990. The table lot is unknown.
High dollar pliers 8620 46 Rc Cr plated
Mid range 4150 43 Rc Nickel plated
Table Lot Could be 3140 or 4130 Rc 37 Zinc plated
They are going to recheck the high dollar pliers.