O-ring Grooving tools with 5 degree side angle

[laminar-flow]

Several years ago I received an email from Micro 100 that advertised their O-Ring grooving cutter. It had a 5 degree angle on each side. This is incorrect and I called and mentioned it to them that the Parker groove dimension tolerance is 0-5 degrees and the cutter side angle should be 2.5 degrees. Nothing happened as I received a few more emails advertising these cutters. Recently, I received another email from Micro 100 advertising said cutter. I called Parker O-Ring division and they agree with my thinking that the cutter side angle should be 2.5 degrees and they would see about giving Micro 100 a call. Lets see if anything changes with these cutters.

The problem is that if a cutter is just one or two degrees off alignment in the lathe, the groove side angle will exceed the tolerance. Why this may not matter on a low pressure static application, on a dynamic seal at high pressure things could be different.

 

[VTM]

Every toolmaker I know makes them like that. Scientific shows 5.5* per side, Internal tool 5*, Accupro, all 5* per side.

 

[in2glamisgirl]

If the tip width is near nominal, the 5 deg sides are well within the high limit boundary. Unless controlled by a feature control frame angles are not features of size but limits of size that the part must not exceed. Use a Parker go-nogo o-ring gauge, it should pass.

 

[CarbideBob]

Yes it should have a clear on both sides of the tool.
Are you feeding sideways at the bottom?
5 per side is a bit high. 2.5 is the real minimum.
Is this a top notch? On a top notch or top lock then 1/2 degree on one side and 5 to 6 on the other as the holder has 3 degrees twist in the machine.
Side relief is not finish cut on a groover. 10 on both still makes a straight walled groove but tool life goes down.
Zero would be really bad.

It cuts on the tip, not the side. Is this hard to understand?

 

[laminar-flow]

See Design Chart and Table 4-2

https://promo.parker.com/promotionsite/oring-ehandbook/us/ehome/ci.Static-Male-and-Female-O–ring-Seal-Design,EN.EN

 

[VTM]

See Design Chart and Table 4-2

https://promo.parker.com/promotionsite/oring-ehandbook/us/ehome/ci.Static-Male-and-Female-O–ring-Seal-Design,EN.EN

Yep, Saw that. But still all the Toolmakers make them 5* side not just Micro 100.

 

[William Lynn]

Our plant had high pressure hydraulics everywhere. Every O-ring groove cut in house had straight walls. If cut correctly, we didn't have any issues.

 

[VTM]

Our plant had high pressure hydraulics everywhere. Every O-ring groove cut in house had straight walls. If cut correctly, we didn't have any issues.

Yep, the spec goes clear to 0* so that makes sense.

 

[laminar-flow]

Here is the micro 100 page. https://www.micro100.com/products/standard---grooving-tools---o-ring-grooving

If the tool is 0, and it is mounted 2 degrees off, your groove will be 0 on one side and 2 on the other. Acceptable. But if the tool is 5 on each side....

 

[triumph406]

I've never specified an angle on the side of an o-ring groove. this is for grooves with o-rings that have gone to 5000psi.

 

[triumph406]

, on a dynamic seal at high pressure things could be different.

The id/od clearance (gap the o-ring can extrude thru) and o-ring hardness are going to be more important then the angle of the side walls at high pressures.

High pressures your going to want to start thinking of using Par-Bak rings

 

[guythatbrews]

It cuts on the tip, not the side. Is this hard to understand?

Not talking about side clearance, but the other way round. Included angle of the sides is 10*.

The id/od clearance (gap the o-ring can extrude thru) and o-ring hardness are going to be more important then the angle of the side walls at high pressures.

That may well be, but ya gotta meet drawing requirements.

Lots of drawings out there with 0-5* tolerance on the groove sidewalls I've cit thousands with 0* angle for safety critical parts. Nary a reject. I never even considered cutting a 2.5* angle. For one thing it's too damn hard to measure the diameter.

If the tool is 0, and it is mounted 2 degrees off, your groove will be 0 on one side and 2 on the other. Acceptable. But if the tool is 5 on each side....

Holy cow, 2* off?

 

[CarbideBob]

Not talking about side clearance, but the other way round. Included angle of the sides is 10*.

My bad.

 

[Ox]

I think that the only reason that there is an angled wall allowed at all is b/c that was likely originally drawn to increase tool life on shave tools on multi-spindles - where the bulk of those fittings are produced. A straight wall will rub the tool, and so when you sharpen it - you are starting a wee bit smaller than you were before, and may have to grind a lot more off to git below the rub.

With some taper, the rest of the tool doesn't rub.


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I am Ox and I approve this post!