Is this riveting ok?

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narfi

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I looked at random spots through your videos, what you display at the 11 minute mark on the 2nd video looks good, the heads are nice without tool marks cutting them with 'smilies' and the tails are all uniform, i see you have a gauge to test the tails with, so you know they are properly driven. Thats great and as you gain more experience and build up confidence you will need to use it less and less, going back after 10-20 driven rivets and testing a few to verify your eye is still 'calibrated' properly.

Im not sure which video, but I saw you had a pile of some drilled out mistakes, the one bent over tail was a good call for drilling out, it seems like you are doing well to me.

Two comments I might make event though I didnt watch all of any of your 3 videos.
#1 Earmuffs or earplugs.... you will thank yourself later in life.
#2 I prefer the largest bucking bar I can use in any situation... Lots of times doing repairs you are stuck with smaller than ideal, but in assembly out in the open like this I prefer larger, not just for ease of driving, but for comfort on my hands. (maybe your bar is one of the heavier types im not sure) Heavier sets the tail faster, and bigger spreads the impact over a larger area of your hand, not as big a deal when young, but as you get older things hurt more....

Looks great to me from what I saw though, keep up the good work.

If you have a specific piece you want looked at just let me know the time on which video and I can look deeper.
 

atalla

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Dec 21, 2016
Messages
26
Location
bc canada
I looked at random spots through your videos, what you display at the 11 minute mark on the 2nd video looks good, the heads are nice without tool marks cutting them with 'smilies' and the tails are all uniform, i see you have a gauge to test the tails with, so you know they are properly driven. Thats great and as you gain more experience and build up confidence you will need to use it less and less, going back after 10-20 driven rivets and testing a few to verify your eye is still 'calibrated' properly.

Im not sure which video, but I saw you had a pile of some drilled out mistakes, the one bent over tail was a good call for drilling out, it seems like you are doing well to me.

Two comments I might make event though I didnt watch all of any of your 3 videos.
#1 Earmuffs or earplugs.... you will thank yourself later in life.
#2 I prefer the largest bucking bar I can use in any situation... Lots of times doing repairs you are stuck with smaller than ideal, but in assembly out in the open like this I prefer larger, not just for ease of driving, but for comfort on my hands. (maybe your bar is one of the heavier types im not sure) Heavier sets the tail faster, and bigger spreads the impact over a larger area of your hand, not as big a deal when young, but as you get older things hurt more....

Looks great to me from what I saw though, keep up the good work.



If you have a specific piece you want looked at just let me know the time on which video and I can look deeper.
Ok thanks I'm using a tungsten bucking bar.
 

Floydr92

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Aug 13, 2013
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359
Location
Scotland
you look to be doing a great job, one little tip would be to try to prevent the edges and corners of the bucking bar from touching anything while riveting, as you end up with marks and scratches fairly easily. if it's too fiddly in some areas, a small piece of masking tape on each corner of the bucking bar can help ;)
 

atalla

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Dec 21, 2016
Messages
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bc canada
you look to be doing a great job, one little tip would be to try to prevent the edges and corners of the bucking bar from touching anything while riveting, as you end up with marks and scratches fairly easily. if it's too fiddly in some areas, a small piece of masking tape on each corner of the bucking bar can help ;)
ok great I try to use blue tape on 3 sides of the bar. Great tip!
Iv heard that a poorly set rivet can still be ok. Rather leave it alone than risk drilling it out? Your thoughts?
 

narfi

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Iv heard that a poorly set rivet can still be ok. Rather leave it alone than risk drilling it out? Your thoughts?
Depends on your definition of 'poorly set'......

It is important that the head is down flat on the skin without any gaps under it.
It is important that all the skins are tight together without any gaps or swelled sections of the rivet between them.
It is important that the tail be 'acceptable'.....

What is "acceptable"????
They dont have to be perfect, but they do have to be within limits.....
Off center of the hole is ok sometimes if its not too far and the swelled area does cover all sides of the hole..... it depends on how much.......
You cant have one side of the hole visible still for sure, that means the rivet is way off to the side and usually bent over even if it looks like it was driven round.

You certainly can do a lot of damage drilling and re-drilling bad rivets, however you are on clean new parts out in the open, if you are very careful with your drilling and rivet removal you should be able to redo it once or twice without any harm done.

There is certainly no shame in needing to redo a few bad rivets. I have been (paid for) doing it almost 20years and just this morning on a project with about 12 rivets needed driven, we had to redo 5 of them at least once and the last one ended with the famous last line "screw it" meaning we had caused enough damage already and that hole was getting a structural screw glued instead. It was on a repair on already egged out holes in a very difficult area to get to, tiny angled area to fit the bucking bar on and offset sets on the gun to even get to the heads... but the point is still valid, no shame in drilling a few rivets and redoing them, just be careful to keep the holes as tight as possible.

There are different ways of doing it, but I like to drill the center out with a smaller bit (for example a #40 bit on a -4 rivet), then with that small hole all the way through i use the proper size bit to drill of just the head (being careful not to go as deep as the skin) I can then pop the head off with a punch the same size which leaves just the drilled shank and tail, I use flush cutters to grab the tail and twist and pull a little to pull it out the back side. If it is still stuck, I have to use the proper size drill to drill a little further into the shank from the head side, usually just deep enough to go through the first skin, then try to pry the tail out again with flush cutters.
 

Angusnofangus

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Sep 29, 2015
Messages
544
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Victoria, Canada
Depends on your definition of 'poorly set'......

It is important that the head is down flat on the skin without any gaps under it.
It is important that all the skins are tight together without any gaps or swelled sections of the rivet between them.
It is important that the tail be 'acceptable'.....

What is "acceptable"????
They dont have to be perfect, but they do have to be within limits.....
Off center of the hole is ok sometimes if its not too far and the swelled area does cover all sides of the hole..... it depends on how much.......
You cant have one side of the hole visible still for sure, that means the rivet is way off to the side and usually bent over even if it looks like it was driven round.

You certainly can do a lot of damage drilling and re-drilling bad rivets, however you are on clean new parts out in the open, if you are very careful with your drilling and rivet removal you should be able to redo it once or twice without any harm done.

There is certainly no shame in needing to redo a few bad rivets. I have been (paid for) doing it almost 20years and just this morning on a project with about 12 rivets needed driven, we had to redo 5 of them at least once and the last one ended with the famous last line "screw it" meaning we had caused enough damage already and that hole was getting a structural screw glued instead. It was on a repair on already egged out holes in a very difficult area to get to, tiny angled area to fit the bucking bar on and offset sets on the gun to even get to the heads... but the point is still valid, no shame in drilling a few rivets and redoing them, just be careful to keep the holes as tight as possible.

There are different ways of doing it, but I like to drill the center out with a smaller bit (for example a #40 bit on a -4 rivet), then with that small hole all the way through i use the proper size bit to drill of just the head (being careful not to go as deep as the skin) I can then pop the head off with a punch the same size which leaves just the drilled shank and tail, I use flush cutters to grab the tail and twist and pull a little to pull it out the back side. If it is still stuck, I have to use the proper size drill to drill a little further into the shank from the head side, usually just deep enough to go through the first skin, then try to pry the tail out again with flush cutters.
I have been smashing rivets full time for the past 27 years and I can say that sometimes it is the easiest, most wide-open rivets that give me the most trouble, and then one that is in a terrible spot will go down just tikkety-boo (another Canadianism). The only person who never messed up a rivet either never shot one or never bucked one.

FWIW, I've never pulled solid rivet tails out like you mention, done it with Cherry-Max, when they are reachable. Whatever works, works.
 

narfi

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Each situation is different but that method usually causes less damage for me than punching from the head side...... esp. on thinner skins.
 

atalla

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Each situation is different but that method usually causes less damage for me than punching from the head side...... esp. on thinner skins.
I had a very hard time pulling the tails of -4's out with a pair of flushcuts. I drilled 80% through than used a 3/32 punch and a backer. Because the rivet was going through 4 pieces she was ribbed. PITA. Thought I was going to destroy everything...
 
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