Weird Snap Rings on Kubotas?

[Mr Haney]

Today I tried to take the forward/reverse pedal off my L3710, and I could not get the snap ring off the pin. I had perfectly good snap ring pliers from Ace Hardware, but the ends were too big to go in the Kubota ring.

Has anyone else run into this? Is there such a thing as a metric snap ring? Is there a specific pair of pliers that work?

 

[TheOldHokie]

Today I tried to take the forward/reverse pedal off my L3710, and I could not get the snap ring off the pin. I had perfectly good snap ring pliers from Ace Hardware, but the ends were too big to go in the Kubota ring.

Has anyone else run into this? Is there such a thing as a metric snap ring? Is there a specific pair of pliers that work?

Yes there are metric snap rings but that is not your problem. You just need pliers with smaller tips. Use drill bits to figure out the size of the hole and buy the correct pliers.

Dan

 

[Lil Foot]

I have a couple sets of these, & have had great service from them.
3 or 4 sizes of tips, straight, right, left, angled.
Not sure if they are still available, but I'm sure you can find similar pliers out there.

 

[Dave_eng]

In case you are not aware of this, snap rings need to be installed in a specific orientation.
Any Kubota manual I have seen has this fact.

Dave

 

[GeoHorn]

I’m having a difficult time interpreting that Internal Snap Ring illustration.

 

[Nicksacco]

Yes, I was too.
I think the bottom line is that the ring has to be installed with the flat side against the "stop".
I think of it as if someone were pushing against me, and I was holding a snap ring, the flat side (sharp side) would be against me.

 

[Flintknapper]

I’m having a difficult time interpreting that Internal Snap Ring illustration.

Yeah, its a poor illustration (if not outright wrong).

Suffice to say an internal snap ring applies its pressure from the major diameter (outward) as you see with most U-joint caps. An external applies its pressure from the minor diameter (inward) typically seen on shafts, etc....

 

[TheOldHokie]

Yes, I was too.
I think the bottom line is that the ring has to be installed with the flat side against the "stop".
I think of it as if someone were pushing against me, and I was holding a snap ring, the flat side (sharp side) would be against me.

Here is a better illustration.

Dan

 

[Flintknapper]

Here is a better illustration.

Dan

View attachment 81213

^^^^^

Excellent!

 

[GeoHorn]

Yeah, its a poor illustration (if not outright wrong).

Suffice to say an internal snap ring applies its pressure from the major diameter (outward) as you see with most U-joint caps. An external applies its pressure from the minor diameter (inward) typically seen on shafts, etc....

That’s not the part I find difficult to interpret (the pressure applied by the snap ring itself.)

What I find difficult is the “force” applied illustration. The part being restricted (on the left) is either a hollow stud inside a tube…. in which case the snap ring is improperly oriented……
… or is a reduced-diameter pin …. which would penetrate thru the snap rings’ I.D. and the snap ring provide almost no useful work.

(I was writing this as Hokie was making his excellent post above. Thanks Hokie…much more agreeable illustration.)

 

[TheOldHokie]

That’s not the part I find difficult to interpret (the pressure applied by the snap ring itself.)

What I find difficult is the “force” applied illustration. The part being restricted (on the left) is either a hollow stud inside a tube…. in which case the snap ring is improperly oriented……
… or is a reduced-diameter pin …. which would penetrate thru the snap rings’ I.D. and the snap ring provide almost no useful work.
8
(I was writing this as Hokie was making his excellent post above. Thanks Hokie…much more agreeable illustration.)

Its a rigid assembly so there are equal and opposite forces in both directions. Why focus on one? In the case of the external ring on a shaft you simply want the flat side against the housing.

Dan

 

[lynnmor]

The two illustrations shown in the above posts show opposite installations. Snap rings are actually heat treated stampings, the radius and sharp edges are a result of that stamping operation are not a design requirement. Yes, they may stay in place better if the radius side is towards the unloaded side.

I have those snap ring pliers with the interchangeable tips, they are a PITA. A good set has a complete pliers for each size but they are expensive.

 

[TheOldHokie]

The two illustrations shown in the above posts show opposite installations. Snap rings are actually heat treated stampings, the radius and sharp edges are a result of that stamping operation are not a design requirement. Yes, they may stay in place better if the radius side is towards the unloaded side.

I have those snap ring pliers with the interchangeable tips, they are a PITA. A good set has a complete pliers for each size but they are expensive.

I agree on all accounts.

"Top" versus "bottom" is hard to distinguish and really makes no difference in practice. Here is an 1-3/4 external ring. Can you see any difference? The CAD drawing does not show any. You have to use a finger to test the edges like a knife blade for sharpness to tell which is the "sharp" edge.

I have interchangeable tio pliers and discarded them in favor ofa decent set of fixed tip pliers ling ago.

Dan

 

[Nicksacco]

Hmmm, I finally had to break down and get myself a set of Knipex snap-ring pliers.
The others I had with replaceable tips were taking years off my life!

 

[D2Cat]

I’m having a difficult time interpreting that Internal Snap Ring illustration.

Looking at the picture of the cross section, one side of the snap ring is rounded and the other is square on the outer diameter. The square side goes into the groove on the opposite side of the pressure of the moving part. This keeps the ring in the groove instead or a rounder shoulder allowing it to slide up and out.

 

[Flintknapper]

That’s not the part I find difficult to interpret (the pressure applied by the snap ring itself.)

What I find difficult is the “force” applied illustration. The part being restricted (on the left) is either a hollow stud inside a tube…. in which case the snap ring is improperly oriented……
… or is a reduced-diameter pin …. which would penetrate thru the snap rings’ I.D. and the snap ring provide almost no useful work.

(I was writing this as Hokie was making his excellent post above. Thanks Hokie…much more agreeable illustration.)

But what if an Internal Snap Ring 'Identifies' as an External ring?

Where does that leave us....?

 

[GeoHorn]

Looking at the picture of the cross section, one side of the snap ring is rounded and the other is square on the outer diameter. The square side goes into the groove on the opposite side of the pressure of the moving part. This keeps the ring in the groove instead or a rounder shoulder allowing it to slide up and out.

I’ll clarify my meaning: I am Not Confused about the purpose and use of a snap ring. I was only commenting on the poor illustrated example Kubota chose to display.

In actual practice…. it makes no difference which side of the stamping is placed into stress… if it ever becomes That Critical….. then you are either using the wrong snap-ring or a snap-ring is inappropriate for that installation. To worry about which side is up or down on a snap ring is approaching ANAL.

 

[Henro]

I’ll clarify my meaning: I am Not Confused about the purpose and use of a snap ring. I was only commenting on the poor illustrated example Kubota chose to display.

In actual practice…. it makes no difference which side of the stamping is placed into stress… if it ever becomes That Critical….. then you are either using the wrong snap-ring or a snap-ring is inappropriate for that installation. To worry about which side is up or down on a snap ring is approaching ANAL.

No clue about this question, but if orientation is not an issue why not make all edges the same?

Manufacturing issue? I.E., comes out this way and making it different would cost more kind of thing? Followed by overthink?

 

[GeoHorn]

No clue about this question, but if orientation is not an issue why not make all edges the same?

Manufacturing issue? I.E., comes out this way and making it different would cost more kind of thing? Followed by overthink?

A snap ring is mfr’d from flat-sheet by stamping with a die. The cut edge and the radiused edge is what is naturally created by the process…. not deliberate. Similar to flat washers.

 

[Dave_eng]

There have been owners on this forum having issues with snap rings coming off. From memory the most prevalent location was on the splined shaft where the upper 3 pt lift arm are attached.

Once the ring groove was cleaned up to remove the damage from the snap ring coming out of its groove and the snap ring installed in the correct orientation, the problem never reoccurred.

I do think in most instances where snap rings are used they are not highly stressed and orientation is not important. As an example, my mitre saw has a lever to tilt the saw which is secured with a snap ring.

Dave