0.018" Shims | McMaster-Carr

Cut into custom shapes to create shims that suit your needs. With thickness tolerances as fine as a strand of hair, the shims will precisely align, space, and level components on dies, presses, and machinery.

You can stack multiple shims to achieve your exact thickness, but stacking more than four may cause them to shift. Remember, fewer shims are better, so a couple of thicker shims are more stable than a bunch of thin shims.

Sheets—Shim stock comes in sheets that are flat packed.

18-8 Stainless Steel—The choice for wet and outdoor areas because it resists rust. However, it will corrode or pit when exposed to salt water and chemicals.

Extreme-Strength 17-4 PH Stainless Steel—Stronger than 17-7 PH stainless steel, it won’t rust in wet and outdoor areas but can’t withstand harsh chemicals like 316 stainless steel.

Carbon Steel—Best for dry areas since moisture will cause it to rust.

Stress-Resistant Spring Steel—Harder and holds its shape better than carbon steel. Use it for high-stress applications, such as leveling heavy machinery. It's best for dry areas since moisture will cause it to rust.

Brass—Picked for its warm, polished look. Similar to 18-8 stainless steel, it resists rusting in wet and outdoor areas.

Temper Rating—Choose half hard to create shims that you’ll need to bend or shape. Opt for full hard to make stronger shims that will maintain their shape under loads.

	Thk. Tolerance	Type	Certificate Form	Specs. Met	Form	Pkg. Qty.		Pkg.
18-8 Stainless Steel





		6" Wide × 50" Long
		0.018"	-0.0009" to 0.0009"	1/2 Hard	Material Certificate	Paper	ASTM A666	Roll	1	0000000	000000



				8" Wide × 12" Long
				0.018"	-0.001" to 0.001"	1/2 Hard	Material Certificate	Paper	ASTM A666	Sheet	1	00000000	00000

				Extreme-Strength 17-4 PH Stainless Steel





								4" Wide × 60" Long
								0.018"	-0.001" to 0.001"	—	Material Certificate	Paper	ASTM A693	Roll	1	0000000	000000

								Carbon Steel





												6" Wide × 50" Long
												0.018"	-0.001" to 0.001"	Full Hard	Material Certificate	Paper	—	Roll	1	00000000	00000



														6" Wide × 100" Long
														0.018"	-0.00075" to 0.00075"	Full Hard	Material Certificate	Paper	—	Roll	1	00000000	00000



																6" Wide × 180" Long
																0.018"	-0.00075" to 0.00075"	Full Hard	Material Certificate	Paper	—	Roll	1	00000000	00000



																		8" Wide × 12" Long
																		0.018"	-0.001" to 0.001"	Full Hard	Material Certificate	Paper	ASTM A109	Sheet	1	00000000	0000



																				12" Wide × 120" Long
																				0.018"	-0.00075" to 0.00075"	Full Hard	Material Certificate	Paper	—	Roll	1	00000000	00000

																				Stress-Resistant Spring Steel





																								6" Wide × 25" Long
																								0.018"	-0.001" to 0.001"	Full Hard	Material Certificate	Paper	ASTM A684, SAE AMS5122	Sheet	1	00000000	00000



																										6" Wide × 50" Long
																										0.018"	-0.001" to 0.001"	Full Hard	Material Certificate	Paper	ASTM A682, ASTM A684, MIL-S-7947	Roll	1	0000000	00000



	12" Wide × 48" Long
	0.018"																									-0.001" to 0.001"	Full Hard	Material Certificate	Paper	ASTM A684, SAE AMS5122	Sheet	1	0000000	00000

	Brass





																										6" Wide × 100" Long
																										0.018"	-0.0018" to 0.0018"	1/2 Hard	Material Certificate	Paper	ASTM B36	Roll	1	0000000	000000

Heavy-Vibration-Resistant Spring Lock Washers for Socket Head Screws

Stop socket head screws from wiggling loose on equipment with constant, vigorous vibration, such as engines, turbines, and generators. These washers have a small diameter to fit under screws with narrow heads. Similar to a spring, they flatten under pressure to add tension between mating surfaces. As long as the washers aren't deformed or otherwise damaged, you can reuse them indefinitely without losing locking strength. Also known as conical washers and Belleville washers.

Stack multiple washers in the same direction to double or triple how much weight they can bear. Stack washers in opposite directions for better deflection, which means they compress further and withstand more shock and movement without loosening.

18-8 Stainless Steel—The choice for wet and outdoor environments, these washers won't rust when exposed to moisture. However, they can't hold up to the harsh chemicals that 316 stainless steel can.

Zinc-Plated Steel—A common choice for areas with occasional exposure to moisture.

Steel—Best for dry environments since moisture will cause these washers to rust.

Top-and-Bottom Serration—Adds friction for extra gripping power.

	ID	OD	Thk.	Overall Ht.	Serration Location	Pkg. Qty.		Pkg.
18-8 Stainless Steel


	M2.5	0.106"	0.189"	0.018"	0.035"	Top and Bottom	50	000000000	000000
	M3	0.126"	0.217"	0.018"	0.035"	Top and Bottom	50	000000000	00000

	Zinc-Plated Steel


			No. 5, M3	0.126"	0.217"	0.018"	0.035"	Top and Bottom	100	000000000	0000
			M2.5	0.106"	0.189"	0.018"	0.035"	Top and Bottom	100	000000000	0000

			Steel


					No. 5, M3	0.126"	0.217"	0.018"	0.035"	Top and Bottom	100	000000000	0000
					No. 6, M3.5	0.146"	0.236"	0.018"	0.035"	Top and Bottom	100	000000000	0000
					M2.5	0.106"	0.189"	0.018"	0.035"	Top and Bottom	100	000000000	0000

Wave Spring Lock Washers

The wavy shape flexes like a spring to keep nuts and screws secure on slightly uneven surfaces. These washers add a small amount of tension to stop fasteners from backing out due to mild vibration. While they don't hold as well as other lock washers, they do grip slightly better than curved washers. They work best in electrical panels, light fixtures, and other light duty assemblies. Since these washers hold their shape when untightened, you can reuse them a handful of times without losing strength.

Steel—Best for dry environments since moisture will cause these washers to rust.

3 Wave—More points of contact than single-wave washers for a better grip.

	No. of Waves	ID	OD	Thk.	Overall Ht.	Pkg. Qty.		Pkg.
Steel


	1 1/16"	3	1.068"	1.500"	0.018"	0.094"	10	000000000	000000