Poor quality factory rivets on F-01204-1 Center Channel

[Cameltron]

I just got done inventorying my 12is Fuse & Wing kit, nothing major except i'm now the proud owner of some RV-14 roll frames, oops....

I was about to start on the fuse kit and was inspecting the F-01204-1 center channel, the quality of the rivets does not pass muster, it definitely doesn't pass what is acceptable in section 5. Some of the rivets seem under squeezed, or barely squeezed at all (notably absent on those are squeezer die marks on the factory head size, that other rivets have). There are also some gaps/sloped rivets and what seem like misaligned holes.

I have emailed vans support but i'm wondering if anyone else has had a similar experience, and maybe received a build on note from vans?

 

[Strikhedonia]

There were a lot of times I had to go to a larger rivet (longer) than was called out in the plans. It looks to me that is what you need to do.

 

[Baron71]

I just got done inventorying my 12is Fuse & Wing kit, nothing major except i'm now the proud owner of some RV-14 roll frames, oops....

I was about to start on the fuse kit and was inspecting the F-01204-1 center channel, the quality of the rivets does not pass muster, it definitely doesn't pass what is acceptable in section 5. Some of the rivets seem under squeezed, or barely squeezed at all (notably absent on those are squeezer die marks on the factory head size, that other rivets have). There are also some gaps/sloped rivets and what seem like misaligned holes.

I have emailed vans support but i'm wondering if anyone else has had a similar experience, and maybe received a build on note from vans?

I just took over and continue the build of an RV-12is (it’s my first build). The fuselage section of the kit is only at page 20-05. Which might just be the stage you need a comparison? I can check on Monday evening CET, how those rivets look at my center line channel.

 

[themiller]

Does your rivet gauge show the “ideal” size or the minimum allowed by the mil spec? If it’s the former, I would check if they are acceptable by the spec which allows for smaller shop heads.

 

[Cameltron]

There were a lot of times I had to go to a larger rivet (longer) than was called out in the plans. It looks to me that is what you need to do.

This part is fabricated by Vans, hence my concern.

I just took over and continue the build of an RV-12is (it’s my first build). The fuselage section of the kit is only at page 20-05. Which might just be the stage you need a comparison? I can check on Monday evening CET, how those rivets look at my center line channel.

I'm right there, start of section 20. Any insight if this is normal would be appreciated!

 

[Brantel]

The rivets don’t bother me as much as that deep gouge in the channel. The actual mil spec for rivets is much more forgiving than the typical gauge.

 

[cactusman]

Those look pretty bad imho. I remember marveling at how well done all my RV12 factory stuff was done. Some of those wing spar assembly big rivets cannot be done easily by the home builder as I recall.

 

[Cameltron]

Those look pretty bad imho. I remember marveling at how well done all my RV12 factory stuff was done. Some of those wing spar assembly big rivets cannot be done easily by the home builder as I recall.

My wing spars look glorious, not a single rivet out of place. That is why I'm so disappointed with this center channel.

 

[Desert Rat]

I'm not sure what parts those are since I don't have a 12. But that one next the big lateral gouge looks like it isn't even swelled enough to fill the hole. A bad rivet here and there isn't going to cause an airplane to fold up, but it seems to me like that one will start to smoke after a while, and the gouge needs to at least have the sharp edges polished out. Just my opinion, but I sure wouldn't be happy if it came from Vans that way.

 

[rocketman1988]

As was stated in a previous post, the rivet gauge shows the largest diameter (thinnest shop head thickness). It is possible to have a smaller/thicker shop head and still be a correctly driven rivet. There are specific values allowed for the min/max diameter and thickness if the shop head. Check the measurements before you decide if the rivet is under driven.

 

[Cameltron]

As was stated in a previous post, the rivet gauge shows the largest diameter (thinnest shop head thickness). It is possible to have a smaller/thicker shop head and still be a correctly driven rivet. There are specific values allowed for the min/max diameter and thickness if the shop head. Check the measurements before you decide if the rivet is under driven.

Thanks to a lot of advice regarding the rivet head measurements, I looked up the spec and there are at least three way under spec. Seems like I should be able to squeeze them myself but I’ll wait till I see what vans has to say.

 

[swift12]

Thanks to a lot of advice regarding the rivet head measurements, I looked up the spec and there are at least three way under spec. Seems like I should be able to squeeze them myself but I’ll wait till I see what vans has to say.

Just give the, a few whacks with a gun and bar….just a few under done. Those rivet gauges are ok but you are best to measure with a caliper. shop head height min and max….no overall diameter matters except min diameter….I wouldnt worry about the gouge….even though it’s ugly you could blend it a little because it’s not across the face and it’s longitudinal. I’m sure vans will say the same.

 

[Cameltron]

Response from Vans "A couple of the rivets are a little underdriven. It is acceptable, if required, to re-strike the rivet with your rivet gun to increase the shop head diameter. The others can be left as is"

I hope the squeezer reaches them, I don't have a standard gun/bucking bar set.

 

[Baron71]

Here are the pictures of my rivets. I wouldn’t have bothered myself, but now I think I just go over the top ones once more with the pneumatic squeezer, since there is a very little play when measuring.

 

[Tdeman]

Regarding the "gouge", the short answer is this a result of the workholding used during manufacturing. This was reviewed by engineering during the in-house implementation of the part. It is strategically aligned parallel with the extrusion grain, parallel with the length of the beam, and it's of a known size/depth (we know that's not a random inclusion of unknown depth). It allows the part to be made accurately, consistently, and efficiently, and is worth the very minimal effect it has.

The long answer is that the raw extrusion comes in twisted, warped, asymmetrical, etc. It is clamped in multiple places and in different directions to straighten and restrain the part during machining. Those gouges are left by the sharp edge of small clamps that hold the top of the channel parallel (while still allowing access for the cutting tools, toolholders, and spindle to come down into the channel.) The CNC machine then removes about 60% of the material from the extrusion to end up as a finished part. During that time, internal stresses are relieved and the part wants to warp in new directions. However, it is restrained nominally by the fixturing allowing uniform floors, walls, and finishes to be produced in the machine, with minimal hand-finishing or blending required.
Compare your part to the part in Baron71's post (which was produced prior to bringing in house), and I think you'll see some of the deviations and hand-finishing we wanted to improve while bringing it in.

 

[Brantel]

Compare your part to the part in Baron71's post (which was produced prior to bringing in house), and I think you'll see some of the deviations and hand-finishing we wanted to improve while bringing it in.

Not that it matters but I am curious as to when you brought these inside? My center section does not have any of the gouges seen above and the milling looks great. I see no evidence of hand-finishing or deviations. I was actually very impressed with it when it came out of the crate.

 

[TThurston]

Not that it matters but I am curious as to when you brought these inside? My center section does not have any of the gouges seen above and the milling looks great. I see no evidence of hand-finishing or deviations. I was actually very impressed with it when it came out of the crate.

I think the major point in this discussion is: Van's quality control is no longer trusted; sad, but true.

 

[Cameltron]

Regarding the "gouge", the short answer is this a result of the workholding used during manufacturing. This was reviewed by engineering during the in-house implementation of the part. It is strategically aligned parallel with the extrusion grain, parallel with the length of the beam, and it's of a known size/depth (we know that's not a random inclusion of unknown depth). It allows the part to be made accurately, consistently, and efficiently, and is worth the very minimal effect it has.

The long answer is that the raw extrusion comes in twisted, warped, asymmetrical, etc. It is clamped in multiple places and in different directions to straighten and restrain the part during machining. Those gouges are left by the sharp edge of small clamps that hold the top of the channel parallel (while still allowing access for the cutting tools, toolholders, and spindle to come down into the channel.) The CNC machine then removes about 60% of the material from the extrusion to end up as a finished part. During that time, internal stresses are relieved and the part wants to warp in new directions. However, it is restrained nominally by the fixturing allowing uniform floors, walls, and finishes to be produced in the machine, with minimal hand-finishing or blending required.
Compare your part to the part in Baron71's post (which was produced prior to bringing in house), and I think you'll see some of the deviations and hand-finishing we wanted to improve while bringing it in.

Thanks for the insight, I have done a fair amount of CNC machining but nothing at production level, so the amount and location of workholding you have seems wise.

Compare your part to the part in Baron71's post (which was produced prior to bringing in house), and I think you'll see some of the deviations and hand-finishing we wanted to improve while bringing it in.

It does look a LOT cleaner from a machine toolpath sense, there are a few more dings, scratches and underdone rivets, which seems to be elsewhere in the in-house process.

Either way, vans said build on and i'm confident to build on after I squeeze those rivets.

Thanks for the responses!

 

[Draker]

The under driven one on 20240203_105137.jpg looks particularly bad. I'd probably accept the rest of them (under the philosophy of Dont Make It Worse), but that one looks like it's barely holding on.

 

[Tdeman]

I think the major point in this discussion is: Van's quality control is no longer trusted; sad, but true.

Over the years (even months or weeks) processes are iterated on and improved. The CNC department has used clamps with blunt edges, and has used clamps with the sharp edges when the blunt-edged clamps didn't provide the reliability we were after. Incoming material variations can be so extreme for some of our extrusion-based parts, that processes and strategies occasionally have to change mid-batch.

So along our path of continuous improvement, you may find some Easter eggs; but they're not all bad.

Not that it matters but I am curious as to when you brought these inside? My center section does not have any of the gouges seen above and the milling looks great. I see no evidence of hand-finishing or deviations. I was actually very impressed with it when it came out of the crate.

I'm glad you appreciated it! Early 2020 was the first time we started producing these.

 

[Brantel]

I'm glad you appreciated it! Early 2020 was the first time we started producing these.

Thanks, mine was made in 2023.