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Poor Riveting

vic syracuse

vic syracuse

Well Known Member
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In the last week I have performed pre-purchase inspections on a couple of aircraft that had really poor riveting, and I thought I should share them with the group here, as I know there are lots of new builders.

The first one was an RV-10 kit that was supposedly pretty complete, including an Eggenfeller engine. Sad to say, the whole aircraft had some of the worst riveting I have ever seen anywhere. I feel bad for the builder, but the buyer certainly dodged a bullet. The aircraft is really more of a restoration project now rather than a kit needing completion. Here's a couple of photos out of the dozens I took. There was every example of a bad rivet I could think of---underdriven, overdriven, misdrilled, crooked, and cracked. With so much help available today between EAA Technical Counselors and the Internet it is intersting to me that someone would just keep pounding away without seeking advice. It's a lot of lost time and lost money. I remember taking the first pieces I riveted to the flight school A&P at which I was flight instructing. He laughed as soon as I walked in the door! I had to drill them all out and he showed me how to properly set them. The rest is history, but the message is we ALL had to learn. Here are some pictures from the RV10:






The second airplane was an RV-7A that has been flying since 2007. It has had multiple inspections by the builder and an A&P. I was again surprised by the extremely poor quality riveting in a very critical area--- the aileron attach bracket. From Van's service letter we know this is an area prone to cracking with even a PROPER riveting job. This particular area is so easy to get right during the build process. It will require precision now to prevent enlargening the holes on the spar. The first photo is of the right wing. The second photo is of the left wing. Note the poor riveting along the lower rear spar on the right wing, and the rivets are reversed on the aileron bracket. That will make doing the SB even harder. The riveting along the lower aft spar is horrible as well.
And take note of the loose jam nut on the elevator. There was a loose one on BOTH the left and right elevator, and it was clear they had never been tightened, as there was paint on the threads below the jaunt. You would think they would be caught on a preflight, let alone the past 7 CI's. What really irritates me is that the SB for the aileron brackets was published 3 months prior to the last Condition Inspection.

I hate to point this out, but paperwork signoffs aren't doing anyone any favors.






 
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WOW

That is definitely disturbing. Buyers beware. Those are some very critical areas to be sloppy. I just performed the SB on my -10 aileron bracket. No excuse for work like that.
 
The loose jam nut is equally disturbing. I think some people fail to appreciate that with the jam nut loose, ALL loads are going through the 2 rivets on the platenut ears.

Here is an example of a "repair" on my Rocket found after I got the thing home:

2ms27h4.jpg
 
WOW, to say the least. I am trying to figure out how someone could think this is even close to OK. Why would they keep going? The dumped rivets wrecked the aft spar.:eek: Even without instruction there is plenty of pictures on the net to let everyone know if you are close to what the rivets should look like. I guess there could be people building with no internet access.

Looks like getting back to a mandatory pre cover inspection might be quite helpful. It would be a lot less work to fix at that stage.......but still a ton of work.

I think it is really important to post these kind of things. There is many builders really trying their best on the build. When it is not perfect they beat their selves up. Every one should strive for excellence but know what it is safe if they cant quite get it perfect. When you don't know, always ask before proceeding.

I would be scared to put tools in the riveted tool box kit if it was riveted like this.:DLOL
 
Kidding aside, most builders worry about quality, and do a fine job because of it. I doubt there is much anyone can do about the sort of personality who accepts the pictured work as OK. And let's not forget, it's not just a builder or A&P inspection issue. A DAR or FSDO person looked at those airplanes at some point.

Here in Montgomery, a TC has it good. Most of my RV builders have been USAF officers rotating through Maxwell as staff or student. As a group, they're intelligent, well motivated types, for whom details really matter. Attitude counts.
 
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This makes me feel much better about the quality of my work.

Of course now if someone offers me a ride I'm going to feel the urge to see their rivet quality first. ;)


Hopefully Vic can inspect my finished product.....just a few more years.
 
Is the plane in the second set of pix of a RV7 or RV12? Considering how many pop rivets it has, this could be a RV12 :rolleyes:
sad it is but glad it is getting noticed and brought to the attention.
 
The second pic really boggles my mind (I guess they all do). Not to mention your HS is attached to those bars, but those bars are attached before installing the bulkhead into the tailcone - can be squeezed or shot with ease.

Is it the pic or is there something going on with the attaching face of that stringer? Looks almost like a backing piece of aluminum...?
 
Now, a lot of my rivets while not pretty I'm quite confident are safe, but looking at some of those photos from the -7 makes me wonder just how strong the structure actually is to be able to accommodate such crappy quality...And gives me a pretty good feeling that I am not going to fall out of the sky nor have my tail twist off.

With the amount of help available,even if it is only "I made a meal of these rivets, what did I do wrong?" posts here, there really isn't an excuse for that kind of construction these days. For something like an airplane, you should never be too proud to be afraid of asking for help, nor should you shy away from constructive criticism (pardon the terrible pun)!

By and large, RV'ers are a friendly bunch and willingly offer assistance, often for the price of a smile and a "thanks mate". I'm sure most of us here would be happy to give up a weekend to show a new bloke how to set a decent rivet, or how to get into an awkward space, or many others with his tail kit than have something like these two planes flying around, because when one of them falls out of the sky, it's "Another experimental plane has crashed...." leading to more grief we don't need from the FAA/CAsA.
 
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Bavafa said:
Is the plane in the second set of pix of a RV7 or RV12? Considering how many pop rivets it has, this could be a RV12 :rolleyes:
sad it is but glad it is getting noticed and brought to the attention.
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It's an RV-7. Pop rivets are OK once in a while, especially if the correct strength pop rivet is used.

As for the fuel tanks being sealed that was asked in another post, the proseal in the tanks was gobbed on pretty good, as in A LOT. I'm sure it covered a lot of bad rivets, but I did not see any evidence of leakage.

Again, I posted these in the spirit of learning and not "look at how bad this was." As a matter if fact, in the spirit of continuous learning I am headed to Don Rivera's Injection class at Airflow Performance the first week of March. I know Dan Horton attended it last year and told me it was really great and I should go. I'm always willing to listen to advice from others, especially those I respect. :) I hope to see some of you there.

Vic

Vic
 
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Andy who? said:
This makes me feel much better about the quality of my work.
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My thoughts exactly. Pragmatically, I feel that my rivets are pretty good, but there's always that little voice in the back of my head whispering "what if you screwed up eeeeveryyyythiiiiing?" But seeing stuff like this definitely helps put my work in perspective. Yeah, I screw up, but I don't think I've ever left a rivet like some of these in place.
 
I was one of those guys questioning everything as well - and while my airplane certainly is not going to go up for any awards, after seeing the homebuilt area at Oshkosh and looking closely at some of the airplanes there, I at least have a warm fuzzy feeling about my build quality now and can fly my airplane relatively confident it's not going to fall out of the sky unless I do something stupid.
 
I'm not condoning sloppy workmanship and I would probably run away from this pre buy as fast as I could!....But, the first two pieces I ever riveted together was just scrap when I was experimenting and learning how to use my tools. I did some pretty pathetic riveting on that piece. Maybe no bent over rivets but all of them were either overdriven or under driven. Then I proceeded to try to tear those pieces apart and was amazed at how strong they were! I wound up tearing the sheets trying to separate them!....Still, sloppy workmanship says a lot about the rest of the build.
 
I'm a friend of the potential buyer of the 7A that Vic inspected (a very good job, BTW).

After a short discussion that even at a very low price, it wasn't a viable buy and we walked on the deal...

As a Tech Counselor, I ve seen a few really bad builds among many good builds. The disappointing ones are when I get call late in the build.
 
ode to Larry Pink

thanks for the heads up. to be fair all aircraft have some "dings" I feel way more confident in my first attempt at building after seeing flying craft and wiggle rivets. my A and P instructor, Larry Pink, probably the best teacher I have ever had, said" if you do your very best it will always be good enough"
and "our least acceptable level of standard should be the FAA standards" that said I am going back into the cave with the confidence that I didn't know I had and am thankful for the post of the workmanship and now have full confidence that I am good and vans aircraft are over engineered, thankfully. so build on and blue skies

billythekid
 
I think much of the poor workmanship is not just technique, but inferior or inadequate tools.

If you want a high quality build, then be prepared to buy high quality tools. The best example of this is getting a tungsten bucking bar. Amazing difference in the quality of driven rivets over using a steel bar. Use some heavy duty clear packing tape to help hold the rivets in place as you buck them. Again, having just a bit of help with this "third hand" can make all the difference while you align the gun and bar with the other hands. Having a pneumatic squeezer is another spendy item that pays off with beautiful consistency in all of your rivets. The adjustable throat was ridiculously expensive for a small piece of steel, but it is worth it when you don't create rows of bad rivets. Get all of the required yokes (more $$$ for a hunk of steel) and your ability to set rivets in different situations becomes easier. I could go on and on.

If you want to build a quality airplane, then be prepared to tool-up and spend the money. It is well worth the investment.

If you are still having riveting issues, then please reach out and find some help before you continue.
 
bruceh said:
The best example of this is getting a tungsten bucking bar. Amazing difference in the quality of driven rivets over using a steel bar.
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I agree in general with the principle of high quality tools, but are you really suggesting that it's not possible to do a good job riveting with steel bucking bars?
 
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bruceh said:
I think much of the poor workmanship is not just technique, but inferior or inadequate tools.
ue.
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Good tools help. But the root cause here is a builder who was willingly to accept work which clearly (and examples are shown in Vans' manuals) was below acceptable standards. I can see arguements over perfect vs good enough; but underdriven, bent over rivets? I'd really like to know the builder's thinking here.
 
As usual, thanks to Vic for providing good topics of discussion through discovery in his course of work.

One of the biggest problems I see, relative to the lack of quality, is builders, sometimes not even new builders, unfamiliarity with the acceptable standards.
I am always amazed at how many people that are building or have built who do not know what AC43-13-1b is, let alone the few chapters or even paragraphs that have the basic guidance as to what is acceptable.
On the older Van's manuals (can not speak for the new ones) Van's includes excerpts from AC43 and other sources on acceptable standards. If this builder read this, he sure didn't take heed.

If you accept the "acceptable standards" as a minimum, then you can strive for an even higher standard. The acceptable standards are still well below what many consider a "quality" build, but at least the airframe will be sound.
As an example, the standard allows for you to leave a bad rivet in place, in certain assemblies, and under certain conditions. It is quite possible to meet the standard and have lots of ugly rivets without impeding the airworthiness of the airplane. Vic's example does not meet this by the way, not even close from the pictures he sent.
 
Might be a simpler explaination

We all know someone who can't work in the shop without an "Adult beverage". I quit using power tools after opening my beverage. Time to just sit back and admire the project. Some people don't feel it makes a difference.
 
Blain said:
We all know someone who can't work in the shop without an "Adult beverage". I quit using power tools after opening my beverage. Time to just sit back and admire the project. Some people don't feel it makes a difference.
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Or fatigue. As one gets more and more tired as they work into the night, the more one probably has a tendency to say "ya, that's good enough."

Cheers,
 
sbal0906 said:
Or fatigue. As one gets more and more tired as they work into the night, the more one probably has a tendency to say "ya, that's good enough."

Cheers,
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This is what makes me call it a night. The back starts to hurt a bit, I feel my patience beginning to shorten - all subtle signs that I need to pack it in. A few nights ago, I was beginning to feel this way when I made this beauty. Granted, it was a fairly difficult reach to shoot and buck at the same time, but my fatigue definitely played a part. I thought about removing it on the spot, but decided to leave well enough alone, mark it with a red sharpie and leave it for another day.

BF2525AF-E23F-49C5-9C61-67211DE7CDA8.jpg


On a side note, I had to fight like heck to get that shop head out.
 
sbal0906 said:
Or fatigue. As one gets more and more tired as they work into the night, the more one probably has a tendency to say "ya, that's good enough."

Cheers,
Click to expand...

Or after making one or two mistakes. Everyone is different but I find that if I'm starting to make mistakes it's time to stop - if only for a little while.
 
Really tired and confused

I realized I was really tired in the shop one night when I found myself trying to measure the continuity of a circuit with the meter probes placed on the drawing! Immediately turned off the lights without touching anything. :)

Vic
 
vic syracuse said:
I realized I was really tired in the shop one night when I found myself trying to measure the continuity of a circuit with the meter probes placed on the drawing! Immediately turned off the lights without touching anything. :)

Vic
Click to expand...

I'm not the only one:D:D. Recently I was looking at a picture from someone's build log on my iPad while working on the plane and tried to blow the fiberglass dust off the part in the picture. I quickly looked to see if anyone was around, turned off the lights, and stepped into the house:D
 
Patience Meter..

My level of patience is usually my indicator. As it gets later in my shop, and I get tired, I usually begin to get impatient with the process. If I keep working, I will likely make a mistake. Over the years, I have learned when to say when in my shop. Also, absolutely no alcohol until the session is over!

The other weird rule I have is: If I drop a rivet and don't see it fall and come to stop with my eyes, then I don't try to find it on the floor. It's considered a "dead rivet" at that point. This is because, in the past, I've picked up what I thought was the dropped rivet and it ended up being a different size. Another time, I found the dropped rivet, inserted and bucked it, only to find that it had been stepped on in the process and the factory head was bent and proud on one edge.
 
I realized a few days ago it was time to pack it in over rivets. I had discovered I had missed one of those small rivets that hold on a nutplate. I looked and looked for one that was not a countersink one, finally with glee found one! Put it in and pulled the mandrel, so proud I had found one - then noticed that the hole called for a countersink type! Went home instantly!
 
When I'm tired I'll stick to either stopping altogether or, if I'm too tired after a long day at work, I'll do things like peel blue vinyl off of parts or deburring parts (no power tools!).
 
ppilotmike said:
My level of patience is usually my indicator. As it gets later in my shop, and I get tired, I usually begin to get impatient with the process. If I keep working, I will likely make a mistake. Over the years, I have learned when to say when in my shop. Also, absolutely no alcohol until the session is over!

The other weird rule I have is: If I drop a rivet and don't see it fall and come to stop with my eyes, then I don't try to find it on the floor. It's considered a "dead rivet" at that point. This is because, in the past, I've picked up what I thought was the dropped rivet and it ended up being a different size. Another time, I found the dropped rivet, inserted and bucked it, only to find that it had been stepped on in the process and the factory head was bent and proud on one edge.
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I don't think that's weird rule. There are always several dropped rivets on the floor if I'm building, and while I have not actually seen their tiny little legs I know they have 'em because they run away and swap places at random.

I decided early on that there's a no-alcohol rule for anything other than shop cleanup, vinyl removal and sheet metal edge deburring. I may let a beer slowly get warm while doing those things... for anything else, the opening of a beer or the arrival of a non-helper signifies the end of the work session.

When my feet or back get tired, it's time to knock off because my patience gets short and I'm much more likely to decide that "airworthy" is good enough.
 
I can't imagine it's possible to build an airplane and not -- somewhere -- read what constitutes a properly set rivet.

The problem here isn't that one particular bucking bar was used or one wasn't used.

The problem here is that the builder didn't care and had no sense or interest in building an airplane properly and setting an acceptable standard of performance.

Ain't nothing you can buy gonna fix that.
 
Goodness

I probably set 1000 rivets before I stopped checking each one with a rivet gauge. Even now when I haven't riveted in a while I'll check the first dozen or so. I will throw in a CherryMax rivet in those few spots where I can't seem to get an adequate set.
 
DaleB said:
I don't think that's weird rule. There are always several dropped rivets on the floor if I'm building, and while I have not actually seen their tiny little legs I know they have 'em because they run away and swap places at random.
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I always tried hard to find dropped rivets, because they do have those tiny feet; and, the next time I had to kneel on the floor, they would run and place themself directly under my kneecap!
Seriously, I am a bit paranoid about foreign object damage. I wanted to be sure a dropped rivet wasn't hiding inside a structure, where by Murphys Law it would jam a linkage somehow.
 
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BobTurner said:
I always tried hard to find dropped rivets, because they do have those tiny feet; and, the next time I had to kneel on the floor, they would run and place themself directly under my kneecap!
Seriously, I am a bit paranoid about foreign object damage. I wanted to be sure a dropped rivet wasn't hiding inside a structure, where by Murphys Law it would jam a linkage somehow.
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I don't want to give the wrong impression. I sweep and vacuum my shop (and project) regularly to keep debris to a minimum. However, when you're down on the ground, looking for a rivet, it's my experience that you WILL find one...just not the right one.;)
 
I have no dog in this particular fight since I'm building another aircraft type. I learned to rivet many years ago in a shop doing structural re-builds. When our QA inspector looked at my work one day and didn't find a single bad rivet I was so proud! Sometimes I thought he just circled rivets to make me mad, but in the long run he drove home some valuable lessons.

Fast forward a few decades. We now have aircraft like the RV12 where the largest portion of the rivets are pulled rivets. Pulled rivets are clearly NOT fool-proof, however they are somewhat more idiot-resistant. Perhaps there is a segment of the population which, upon inspection of their work, be advised to concentrate on a "pulled rivet" airplane.

Then again, with human personalities being what they are, the folks who will put together an airplane with multiple rivet deficiencies are likely the folks who either would not seek the counsel of more experienced builders, or would not accept that counsel if it was given.

Without doubt we must be vigilant and this discussion thread is a good opportunity to keep ourselves on our toes. Whenever I see where somebody else has screwed up I take that as an opportunity to ask myself if I have done the same or similar. It's this sharing of knowledge that makes the aviation community a true community.
 
I have very similar rules as those expressed above. I never use a rivet once it's taken a trip to the floor. There's just too much opportunity to damage a rivet by stepping on it, rolling over it with my stool, etc. Rivets are cheap, mistakes can be costly.

I also struggled with deciding when I was too tired to work early in my project. The typical day then was go to work early, leave work early in the afternoon, then work on the project into the evening. I discovered the hard way that when I got fatigued it only took me seconds to make mistakes that required hours to repair. My pattern now (with thanks to my flexible work schedule) is to get up early and get 1-2 hrs in the shop before I go to work. I find that within 10 minutes of getting up, I can have a cup of coffee and be in the shop completely alert and can work with laser focus over that 1-2 hr period. Even on the weekends it's easy to keep this early morning shop schedule, and I've come to covet my early mornings as part of my daily routine.
 
BobTurner said:
I always tried hard to find dropped rivets, because they do have those tiny feet; and, the next time I had to kneel on the floor, they would run and place themself directly under my kneecap!
Seriously, I am a bit paranoid about foreign object damage. I wanted to be sure a dropped rivet wasn't hiding inside a structure, where by Murphys Law it would jam a linkage somehow.
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Everyone should be paranoid about foreign object damage (FOD). During a routine flight control check while taxiing out in an MD-88 I felt significant binding in the elevator. A week later I called the maintenance department to find out the cause of the binding. The airplane had just returned from depot level maintenance and the shop ends of some drilled out rivets jammed between the control cable pulleys! I always vacuum out my airplane at every opportunity in every crevice.
 
Condition of Builder

I don't go anywhere near my table saw after about...8pm. I still have all my fingers except when I miscount them.
 
Thanks for posting Vic. Your posts about bad build quality, bad maintenance, and other problems you encounter are especially valuable to non-builders like me. Could these posts be assembled in dedicated "stickies" by subject (or even better in their own forum in the education section) so they would be easy to find and study?
 
Thanks for the comments, Chris. That's a good idea. I need to motivate myself to contribute once a week or so with some of my findings so we all can learn.

Vic
 
Vertical fin attach

Here's another one on an RV-7 found this past week. It had been flying for 7 years, and allegedly maintained by an A&P. Personally, I think the riveting shown should have been caught on the initial airworthiness inspection, if not the 6-7 subsequent inspections. I think 2 out of the 7 rivets are acceptable. :(

Just remember that there is a simple formual for determining a set rivet:

It should be approximately 1/2 the original diameter in height and approximately 1.5 original diameters in width. Diameters here are referring to the unset rivet measurements. As an example, a 1/8" rivet as seen here (AN470) should measure 3/16" across and 1/16" high after being set. After a while you will be able to eyeball it.


 
acam37 said:
Looks like those could be hit again and they would be perfect
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I'm really new at aircraft sheet metal work, but if workmanship like this that is fairly accessible and visible has been considered acceptable - both for the initial airworthiness sign-off and subsequent condition inspections - what about all of the inaccessible (and long hidden) fasteners in the wings and other critical areas?

All I can surmise from seeing these and other examples of marginal construction is that Van and his engineers did a heck of job designing to the lowest common denominator. Otherwise, these airplanes would be falling out of the sky.

For me, it confirms the advantage of having several sets of trained and experienced eyes (in my case at Synergy) look at each and every component I build.
 
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Where do you find these planes?

Geez! I mean those do not look good to anyone. Not even to an amateur like me. How the heck do these birds get signed off? Kudos to Vans for over-engineering the heck out of these planes. Thanks for posting these...
 
2 of 7 or 2 of 9?

vic syracuse said:
... I think 2 out of the 7 rivets are acceptable. :(

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Vic, I agree completely that these photos are very helpful.

One point - I assume you mean 2 of the 9 rivets there are ok? Can I guess you mean the one on the far left and the one at the lowest point on the photo? They seem to be slightly overdriven IMHO, but I agree that they look "ok", from the angle I can make out in the photo. Perhaps the bottom right corner rivet might be "ok", if slightly underdriven. If a picture is worth a 1000 words, seeing it in 3d with two live eyes is worth 1000 pictures. :)
 
Yes, my bad. I guess I can't count. :)
The two you mentioned are set properly. The others could be fixed in about 2 minutes with a gun and bucking bar. They are easily accessible.

There have been a few comments about the Vans aircraft being over engineered. No doubt. I remember taking my first piece on the rv-4 to the FAA when we had to to get preclosure signoffs. He asked if I was building a tank. I didn't know any better until I looked at the inside of a Cessna tail. Yikes! I didn't understand how it stayed on, but I certainly understood why they were cracking from everyone pushing down on the tails to move them around!

That being said (that they are overengineered) they should still be built right. Anything worth doing is worth doing right. These pictures I am showing you are not becasue I am picky. Quite candidly, none of these would have been given an airworthiness certificate if I was the DAR. A lot of them are fixable---some even during the course of the inspection like the RV-7 vertical fin. Others, like the RV-10, are going to take a major rebuild.

As someone also mentioned, it makes you wonder about the rest of the aircraft. I am working on posting some pictures in a bit that will drive that point home with a big hammer. :(

Vic
 
What else is lurking

So, in the spirit of what else might be lurking behind visible poor workmanship, take a look at the following:

Missing rivets on the horizontal stabilizer. Should have been caught on airworthiness inspection.



Pop rivets on the engine mount attachments. Really?



How's this for wallowed out holes on the landing gear attachment?



This is the horizontal stabilizer attachment, the first clue that one might want to look deeper.



Real friends don't let their friends buy RV's without a thorugh prebuy.

Vic
 
On the subject of acceptable rivets, I'm wondering is it ok if you have a properly formed shop head that is "overdriven" (won't fit in the rivet gauge), but still meets the minimum head height? Hope that makes sense.
 
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