26-14 Question: Break these edges

So I understand that I should read ahead in the plans, but.....

Step 1 on 26-14 the plans call for breaking the back edge of the F-01484. But on page 26-11 step 6: it states to dimple all the #30 and #40 holes.

So not thinking that I would at some point have to break the back edge, I dimpled the holes along the back edge of skin. I typically use an edge roller to break the edges, which is impossible after dimples are in place. I guess that I could use a hand seamer, but that does not give a nice edge break. I could undimple, but I don't really like that option. I will probably not break the edge at this point.

My question is why isn't the call out for the edge break on on page 26-11 before the dimpling. Or did I miss something.

Stockmanreef said:

Or did I miss something.

Click to expand...

It looks like you and the plans writer both did.

As you pointed out, there is an expectation (and the manual repeatedly says to do so) is for the builder to read the entire section and have a complete understanding of what is being done. Along with the expectation that Section 5 has been read and understood (where it describes breaking edges and that it needs to be done prior to dimple countersinking.

But, since there is specific instructions to break the specified edge it should be written in a proper sequence.
As far as I am aware, you are the first to point out this error. I will make note of it for future revisions. In the mean time I will add it to the gotchas thread...

It only took me doing this to two other skins to finally learn to look for edge breaks before dimpling any skin. For my previous errors I had a special roller made by Mike at Cleaveland tool so that I could break the edge with the dimples in place. Unfortunately I just checked the skin and the dimples are too close to the edge to be able to use that otherwise I would have just sent it to you.

Best of luck getting it sorted out.

I have another question about the plans. Why would useful information be taken out of the plans during a revision?

For example, 26-12 in current plans (I think that they are the most current one) don't call out the #30 final drill hole count, while the old ones did (see image below).



Again, maybe the count is not needed, by why take it out. The count was correct.

Just curious.

Stockmanreef said:

I have another question about the plans. Why would useful information be taken out of the plans during a revision?

For example, 26-12 in current plans (I think that they are the most current one) don't call out the #30 final drill hole count, while the old ones did (see image below).



Again, maybe the count is not needed, by why take it out. The count was correct.

Just curious.

Click to expand...

Because the count actually wasn't correct... based on common standards for drawings.

The comments and details of a figure are supposed to be related to what is actual shown in the figure. There is 8 to do on the airplane, but only 4 in the figure. So saying 8 could actually be confusing to some people (all depends on their frame of reference)
So it no longer needs a 3 count listed, because it actually has the holes that you need to final drill circled. Then you do the same on teh other set of parts for the opposite side.

I understand what you say, but on the figure it also says final drill 26 #30 holes. I was not confused at all.

Although I have trouble reading ahead, I can still do simple division.

Is it common practice to call out rivet count? If so, then why did Van's just not divide by 2.

Stockmanreef said:

I understand what you say, but on the figure it also says final drill 26 #30 holes. I was not confused at all.

Although I have trouble reading ahead, I can still do simple division.

Is it common practice to call out rivet count? If so, then why did Van's just not divide by 2.

Click to expand...

Your right.... same situation. That is one that should have changed with the other.
It is complex to write a manual for something like this, but it is hard to ever make anything perfect.
The biggest struggle is that the better the plans get, the higher the expectations of the builders get...... everyone is trying though.