1/2 Hex Round bearing or bushing?

What alternatives exist for 1/2" HEX Bearings? Are there any bushings or round flanges bearings that work?

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I would not recommend using bushings. My team uses smaller bearings with washers for low-medium torque situations


The bolt screws into a tapped hole in the hex.

We also have this dead-axle 3d print thing that I made. It has a 24 tooth pulley pattern for actuation


it has 2 bearings, a 1.5in spacer inside, and a 1/4-20 bolt going through. You can use a nut or a tapped hex shaft to tighten the whole thing.

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A lot of teams use rounded hex shaft with round bearings. For non-rounded hex shaft, you’re pretty much stuck with hex bearings.

If you are using rounded hex, any 13.75mm ID bearing or bushing should work.

Edit: what @Jon_Stratis said

The reduced diameter with washers is a good tip, but there are plenty of excellent uses for bushings and more than a few cases where a bushing is the correct choice before packaging is considered.

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I know we call them bushings but in reality they are bearings, just not roller bearings.

Thirifybot sells some nice ones that we have used successfully in the past. They are really good at reducing packaging size.

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If you have access to a lathe you can use any bearing you want. We’ve been slowly converting more and more stuff over to small diameter bearings either with shoulder bolts or turning down the ends of the shafts.

My team is looking into using flanged sleeve bearings/bushing with thrust bearings to create a low speed high torque arm using SplineXL. I am not 100% sure on the details as I am working on a different subsystem but from my understanding we will put the thrust bearing in between the flange of the bushing and our structure piece. We are doing this for three reasons the first being the lack of supported flange bearings for the SplineXL ecosystem along with it being a low speed task but high torque so we are hoping it will reduce wear on the shaft, support structure, and the motor and also help reduce backlash. The mentors on the team summed it up to me in very simple terms that bearings are for high speed application while bushings are for low speed with medium to high force on the joint. This is a really good article that goes in depth into the difference and when to choose one over the other.

Bushings should definitely be used in the right situation :stuck_out_tongue:

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We have only used bushings in high torque scenarios. I remember last year we had a jointed arm with a wrist joint for our collector. We made the two big joints out of delrin and ran a maxspline through them. The delrin acted sort of like a bushing.

Pretty much any other scenario we used bearings.

If anyone has more uses for bushings, I would love to know more.

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While I agree with your use of the bushings, I don’t think you’re describing it well. Bearings (be they rolling element or plane bearings “bushings”), are not, as a general rule, intended to carry any torque. The bushings used as bearings in FRC are liable to wear or melt if used in high speed applications, but, plastic or oilite bearings are much cheaper and lighter than large ball bearings of the same ID. Therefore they are great in very high load arm joints because they won’t run very fast and large radial and torsional loads require large tube axles, and thus bearings. There are plenty of large high load bearings in FRC that would never work with bushings because their speeds are too high even though loading is similar, most notably swerve azimuth bearings.

In an FRC environment I would only use bushing type bearings in low speed applications, but that could be small stuff like joints in a 4-bar or slow turret pinions, but the cost and weight savings are negligible below 1". The Oilite and plastic bushings we use in FRC also tend to be higher friction than ball bearings but that rarely make much of a difference.

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Thx, this was very helpful!

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