Page 10-21 Step 4 Question

[md9680]

Step 4: Rivet the F-01497A and F-01497B Cable Guides to the F-01473-L & -R Aft Fuse Side Skins as shown in Figure 2.

In step 4 as per instructions (I thought!), I blind riveted the Cable Guides to the side skins. In the process, 4 of the 12 AACQ4-4 blind rivets' mandrels broke and left about 1/3" protruding. I thought this unusual but cut the mandrels with a close-to-flush cutting tool and didn't think much about it until they were all riveted. Only after checking the work against the plans did I notice that I forgot to add the washers. This effectively increased the length required for the puller to pull.

Yes, I now need to somehow remove all those AACQ4-4 rivets, but could my missing the washers have contributed to the broken mandrel issue?

Thanks.

 

[Cessnadog]

Never say never, but a couple of my mandrels broke early as well.

 

[lipper03]

Mine did similar but with the washers, but I also wasn’t using the new hardware, which is a longer rivet. I asked support, asked if they were secure, they are, so they said build on.

 

[md9680]

Never say never, but a couple of my mandrels broke early as well.

Good to know it wasn't just me. Thanks.

 

[md9680]

Mine did similar but with the washers, but I also wasn’t using the new hardware, which is a longer rivet. I asked support, asked if they were secure, they are, so they said build on.
View attachment 42608

Thanks for the pic. It turned out to be easier than I thought it would be to drill the rivets out or at least free the parts for reuse after punching out the tails. I'm hoping inclusion of the washers will make for fewer or even no prematurely broken mandrels. My kit is almost 3 years old. Maybe I should ask Van's if the longer rivet will work better?

 

[georgemohr]

I had a slightly different problem. My mandrels pulled all the way through the rivet. I left it as was and moved on. Not sure about your issue but it makes sense that the lack of washer might affect.

 

[TASEsq]

I ordered some -3 length rivets and had good success. I think the issue is the -4 length are too long - the mandrel is designed to break at a specific place and if the grip is too long this break place ends up outside of the rivet.

You can see the difference here:
https://tasrv14.blogspot.com/2019/09/10-21-26-systems-install-in-aft-fuse.html?m=1

 

[md9680]

I ordered some -3 length rivets and had good success. I think the issue is the -4 length are too long - the mandrel is designed to break at a specific place and if the grip is too long this break place ends up outside of the rivet.

You can see the difference here:
https://tasrv14.blogspot.com/2019/09/10-21-26-systems-install-in-aft-fuse.html?m=1

Thank you for your illustrated presentation of the differences between the the -3 and -4 length rivets. It's understandable and I'm now considering -3s for the thinner pieces. If I can just remember to use the washers this time, perhaps there won't be any broken mandrels. Well, one can hope...

 

[n4322b]

Options

Apart from the missing washers there’s also an option to fit external fainting pieces over the cable exits that you might want to consider before riveting again ?

 

[md9680]

Apart from the missing washers there’s also an option to fit external fainting pieces over the cable exits that you might want to consider before riveting again ?

Yes. I was kinda wondering why Van's didn't use them. Saw some over at Aircraft Spruce. I presume they would be placed underneath the nylon guides on the inside of the skin?

 

[DonMcKee]

Hmm, the current rev of the plans (pg. 10-21, Rev 2) call for using AACQ-4-6, rather than the AACQ-4-4 that was recommended before. These longer rivets resulted in the attached pics. This can't be right.

 

[TASEsq]

Hmm, the current rev of the plans (pg. 10-21, Rev 2) call for using AACQ-4-6, rather than the AACQ-4-4 that was recommended before. These longer rivets resulted in the attached pics. This can't be right.

That’s bizarre that they would change the callout for those to -6 length! The -3 work the best in my opinion. Not a structural bit.



Page 33-12 is where you install the forward guides on the tunnel sides and it called out -6 for the thicker pieces and -3 for the thinner pieces. I believe this is correct go the aft guide as well.

 

[DonMcKee]

To follow up, I sent this query to Van's:

In the RV-14A KAI on pg 10-21, Rev 2, there is a call out for using AACQ-4-6 blind rivets for attaching the F-01497A and F-01497B cable guides (the previous rev of the plans called for AACQ-4-4 rivets in both places). The longer rivets resulted in this: [pics attached to earlier post]

I figured there must be a good reason why the plans were changed to call for the longer rivet, when the shorter rivets were already causing problems, but this can't be right. Should I just remove these rivets, and use AACQ-4-4 on the thick guides, and AACQ-4-3 on the thin guides?

I received this reply:

I agree with your assessment and solution. It was changed because the AACQ-4-4 were deemed too short. But this is clearly wrong too.

Best regards,

Tony

So I did as suggested, and pics of the results are attached. If I were to do it again, I'd try to source AACQ-4-5's for the thicker guides (not currently available at the Van's store), and -3's for the thin ones. BTW, one mandrel from one of the -4's on each side of the fuse pulled through (visible in the pic).

 

[mc607]

Thanks for your update Don. That’s what this site is all about, sharing the knowledge.