Help with bearing selection?

If you have the luxury to select what bearings to choose from, don't think of any bearings than the standard ones, the following ball bearing list will be your best selection in terms of price and availability, they are metric, so all dimensions are in millimeters, going metric is much more affordable, the following bearings are available in multiple designs.

Click on each of the links to find all the different design, let's take the first item as an example, 6000 ball bearing is just an open bearing that can be used inside any contained design like a housing that won't get any contamination, well that is not easy to find, that's why they invented the 6000-2RS & 6000ZZ, two closed designs, the first is usually marked 6000RS is a double rubber sealed closed bearing, the seal is installed in a pre-made outer ring groove, with grease already in there, nice, huh? as for the 6000ZZ, usually marked 6000Z, closed with metal shield with also grease inside.

Here is what the open Bearings look like, in our example it is the 6000 ball bearings

 The metal shielded 6000ZZ ball bearings, looks like this

And the rubber sealed 6000-2RS ball bearings looks like this

The 6000 bearings snap ring looks like this

Well, now is the time to select your ball bearings of the following list,

Metric Deep Groove Ball Bearings 6000 Series

Part No.	Bore			Outside Diameter			Width		Static Load lbs.	Dynamic Load lbs.
Click To find	Metric mm	in Inches	Tolerance	Metric mm	in Inches	Tolerance	Metric mm	in Inches
6000 Bearings	10	.3937	-.0003	26	1.0236	-.0004	8	.3150	440	790
6001 Bearings	12	.4724	-.0003	28	1.1024	-.0004	8	.3150	500	805
6002 Bearings	15	.5906	-.0003	32	1.2598	-.0005	9	.3543	565	965
6003 Bearings	17	.6693	-.0003	35	1.3780	-.0005	10	.3937	625	1040
6004 Bearings	20	.7874	-.0004	42	1.6535	-.0005	12	.4724	1000	1500
6005 Bearings	25	.9843	-.0004	47	1.8504	-.0005	12	.4724	1115	1730
6006 Bearings	30	1.1811	-.0004	55	2.1654	-.0005	13	.5118	1550	2280
6007 Bearings	35	1.3780	-.0005	62	2.4409	-.0005	14	.5512	1905	2760
6008 Bearings	40	1.5748	-.0005	68	2.6772	-.0005	15	.5906	2085	3050
6009 Bearings	45	1.7717	-.0005	75	2.9528	-.0005	16	.6299	2735	3620
6010 Bearings	50	1.9685	-.0005	80	3.1496	-.0005	16	.6299	2945	3760

Metric Deep Groove Ball Bearings 6200 Series

Part No.	Bore			Outside Diameter			Width		Static Load lbs.	Dynamic Load lbs.
Click To find	Metric mm	in Inches	Tolerance	Metric mm	in Inches	Tolerance	Metric mm	in Inches
6200 Bearings	10	.3937	-.0003	30	1.1811	-.0004	9	.3543	500	885
6201 Bearings	12	.4724	-.0003	32	1.2598	-.0005	10	.3937	595	1055
6202 Bearings	15	.5906	-.0003	35	1.3780	-.0005	11	.4331	675	1180
6203 Bearings	17	.6693	-.0003	40	1.5748	-.0005	12	.4724	890	1500
6204 Bearings	20	.7874	-.0004	47	1.8504	-.0005	14	.5512	1390	2220
6205 Bearings	25	.9843	-.0004	52	2.0472	-.0005	15	.5906	1565	2415
6206 Bearings	30	1.1811	-.0004	62	2.4409	-.0005	16	.6299	2255	3360
6207 Bearings	35	1.3780	-.0005	72	2.8346	-.0005	17	.6693	3070	4430
6208 Bearings	40	1.5748	-.0005	80	3.1496	-.0005	18	.7087	3520	5035
6209 Bearings	45	1.7717	-.0005	85	3.3465	-.0005	19	.7480	4005	5655
6210 Bearings	50	1.9685	-.0005	90	3.5433	-.0006	20	.7874	4450	6065

Metric Deep Groove Ball Bearings 6300 Series

Part No.	Bore			Outside Diameter			Width		Static Load lbs.	Dynamic Load lbs.
Click To find	Metric mm	in Inches	Tolerance	Metric mm	in Inches	Tolerance	Metric mm	in Inches
6300 Bearings	10	.3937	-.0003	35	1.3780	-.0005	11	.4331	845	1430
6301 Bearings	12	.4724	-.0003	37	1.4567	-.0005	12	.4724	1045	1655
6302 Bearings	15	.5906	-.0003	42	1.6535	-.0005	13	.5118	1215	1975
6303 Bearings	17	.6693	-.0003	47	1.8504	-.0005	14	.5512	1470	2335
6304 Bearings	20	.7874	-.0004	52	2.0472	-.0005	15	.5906	1750	2730
6305 Bearings	25	.9843	-.0004	62	2.4409	-.0005	17	.6693	2385	3690
6306 Bearings	30	1.1811	-.0004	72	2.8346	-.0005	19	.7480	3130	4605
6307 Bearings	35	1.3780	-.0005	80	3.1496	-.0005	21	.8268	4020	5775
6308 Bearings	40	1.5748	-.0005	90	3.5433	-.0006	23	.9055	5020	7060
6309 Bearings	45	1.7717	-.0005	100	3.9370	-.0006	25	.9843	7000	9120
6310 Bearings	50	1.9685	-.0005	110	4.3307	-.0006	27	1.0630	8010	10750

    Other designs like flanged and with a groove and a snap ring can help ease the assembly of your machine, but not as common as the ZZ & 2RS designs, so if I get to choose I would always go for 2RS design, well, as for electric motors, I suggest going for the ZZ design, they have lower friction factor because there is no contact between the shield and the inner ring, as for the rubber seal, installed in the outer ring and in contact with the inner ring.

The above list of ball bearings are from the 10mm bore to 50mm, again, you won't find more economical and efficient sizes, the most common material for the inner rings, outer rings and the balls are chrome steel, also knows as 52100, but can be available in stainless steel, ZrO2 ceramic, Si3N4 ceramic, SiC ceramic or even plastic.

Good luck and thanks for reading!