BK12 BF12 Bearing Block Set for SFU20 Ball Screw
Key attributes
Other attributes
This type of ballscrew support is very common in the DIY CNC world. It never had our preference, since it’s not so easy to mount a stepper motor or servo to this support. We prefer to use the FK type bearing blocks with MB Motor Backets in our applications. But we see that clients keep on requesting these blocks. Further we see that when you wish to drive the ballscrew with a belt, this is a good and easy standard solution. So we decided to start sales of these products as well. There are many BK blocks on the market, and the problem is, they all look the same. Prices differ greatly. We have chosen to buy/sell only the highest quality bearings (P5 Taiwan) suitable for ballscrews in quality class C3 through-C10. The blocks we have in stock with the high quality bearings is the type that can be made backlash free, by adjusting the pre-load on the angular contact bearings. Be aware that many webshops offer only the C7 type, which has normal deep groove bearings, and then don’t have any pre-load, which means you will have backlash in axial direction. When you add the BK support to your cart, the website, will advise the correct BF Floating Support,which is needed on the other side of the ballscrew.
Component features:
* Steel Housing
* Axial angular contact bearings
* C3 High Quality bearings made in TAIWAN (don’t compare price with C7, it’s much lower quality)
* Adjustable pre-load allowing zero axial backlash (not possible with C7!)
* Scope of delivery: Housing + Bearings + 2 Spacers + Locking nut
* This type of bearing block is used on the fixed side of the ballscrew, for taking the axial + radial loads
* Exchangeable with other brands like THK, NSK, KURODA
Model No. | Bearing | L | B | H | b | h1 | B1 | H1 | |
journal | ±0.02 | ±0.02 | |||||||
diameter | |||||||||
d | |||||||||
mm | mm | mm | mm | mm | mm | mm | |||
BF10 | 8 | 20 | 60 | 39 | 30 | 22 | 34 | 32.5 | |
BF12 | 10 | 20 | 60 | 43 | 30 | 25 | 35 | 32.5 | |
BF15 | 15 | 20 | 70 | 48 | 35 | 28 | 40 | 38 | |
BF17 | 17 | 23 | 86 | 64 | 43 | 39 | 50 | 55 | |
BF20 | 20 | 26 | 88 | 60 | 44 | 34 | 52 | 50 | |
BF25 | 25 | 30 | 106 | 80 | 53 | 48 | 64 | 70 | |
BF30 | 30 | 32 | 128 | 89 | 64 | 51 | 76 | 78 | |
BF35 | 35 | 32 | 140 | 96 | 70 | 52 | 88 | 79 | |
BF40 | 40 | 37 | 160 | 110 | 80 | 60 | 100 | 90 | |
E | P | d3 | d1 | d2 | h | Basic load rating | Mass | ||
Radial direction | |||||||||
Dynamic | Static | ||||||||
C | C0 | ||||||||
mm | mm | mm | mm | mm | mm | kN | kN | kg | |
15 | 46 | 5.5 | 6.6 | 10.8 | 5 | 3.35 | 1.4 | 0.29 | |
18 | 46 | 5.5 | 6.6 | 10.8 | 1.5 | 4.55 | 1.96 | 0.3 | |
18 | 54 | 5.5 | 6.6 | 11 | 6.5 | 5.6 | 2.84 | 0.38 | |
28 | 68 | 6.6 | 9 | 14 | 8.5 | 9.6 | 4.6 | 0.74 | |
22 | 70 | 6.6 | 9 | 14 | 8.5 | 9.4 | 5.05 | 0.76 | |
33 | 85 | 9 | 11 | 17.5 | 11 | 14 | 7.85 | 1.42 | |
33 | 102 | 11 | 14 | 20 | 13 | 19.5 | 11.3 | 1.97 | |
35 | 114 | 11 | 14 | 20 | 13 | 25.7 | 15.3 | 2.22 | |
37 | 130 | 14 | 18 | 26 | 17.5 | 29.1 | 17.8 | 3.27 |