I had asked in a previous thread about deburring rivet holes using just Scotchbrite and got some great answers. The thread asked about a few other things but I'd like to concentrate just on deburring, hence a new thread.
It took me a while to figure out why there seems to be so many different ways/opinions on how to do what seems to me an incredibly simple thing. Then it struck me - deburring (holes) means two different things depending on who you are talking to: To me it is simply the act of knocking off extra metal pieces that will cut skin or interfere with a washer or bolt being torqued down or a rivet sitting well in its hole; to others it includes chamferring (not countersinking) the hole to relieve a stress point at the edge of the hole.
So I'm interested in the why here not how. Others have supported the need to chamfer by referring to "best practices", or its been this way for many years and is established procedure, etc. Now I'm not arguing any of that. I don't have the technical background to do so, but I have found references to just deburring the surface in some surprising places.
1. Is there a reason to deburr (not chamfer but deburr) inside the hole, ie immediately below the edge?
2. On a skin as thin as .025", does anybody get concerned with removing more than 10% of both sides when they chamfer to deburr? Can you really just do a twist or two on both sides with say a 100* countersink or larger bit, and be confident you haven't removed too much?
3. So here is my main question: Can someone provide me with a reference that chamfering to relieve stress on a rivet hole is required or proven to reduce cracking? I can't for the life of me find anywhere that this is indeed an established industry standard or best practice or proven to alleviate stresses. I would like to read about it. Stress issues with 90* edges and deep scratches I get. Is it correct to look at that rivet edge as the same 90* problem so needs to be removed?
Sorry for the long winded questions. Mercifully, I removed the how I got so smart with just a high school education part
Personally, I don't see this as over thinking. I see it as a desire to learn. I'm particularly enjoying the learning new things part of this.
Oh, and Happy Thanksgiving (Canada).
It took me a while to figure out why there seems to be so many different ways/opinions on how to do what seems to me an incredibly simple thing. Then it struck me - deburring (holes) means two different things depending on who you are talking to: To me it is simply the act of knocking off extra metal pieces that will cut skin or interfere with a washer or bolt being torqued down or a rivet sitting well in its hole; to others it includes chamferring (not countersinking) the hole to relieve a stress point at the edge of the hole.
So I'm interested in the why here not how. Others have supported the need to chamfer by referring to "best practices", or its been this way for many years and is established procedure, etc. Now I'm not arguing any of that. I don't have the technical background to do so, but I have found references to just deburring the surface in some surprising places.
1. Is there a reason to deburr (not chamfer but deburr) inside the hole, ie immediately below the edge?
2. On a skin as thin as .025", does anybody get concerned with removing more than 10% of both sides when they chamfer to deburr? Can you really just do a twist or two on both sides with say a 100* countersink or larger bit, and be confident you haven't removed too much?
3. So here is my main question: Can someone provide me with a reference that chamfering to relieve stress on a rivet hole is required or proven to reduce cracking? I can't for the life of me find anywhere that this is indeed an established industry standard or best practice or proven to alleviate stresses. I would like to read about it. Stress issues with 90* edges and deep scratches I get. Is it correct to look at that rivet edge as the same 90* problem so needs to be removed?
Sorry for the long winded questions. Mercifully, I removed the how I got so smart with just a high school education part
Personally, I don't see this as over thinking. I see it as a desire to learn. I'm particularly enjoying the learning new things part of this.
Oh, and Happy Thanksgiving (Canada).