Rivets

[T L McClary]

Has anyone put together a cross reference of Murphy part number to MS /
industry standard part numbers for the rivets Murphy is supplying with
their kits?

With the discussion and recommendations on the list a couple of weeks ago
on rivet length for the rivets used in the aileron assembly offset, I
thought a cross reference would be a nice starting point for us beginners
in trying to find the correct shorter rivets.

Terry

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[Jims170A]

Hi Terry
The link below has a lot of info on rivets used in Murphy Aircraft.
Its in Murphy support area "Rivet information Technical Support 04 Nov 1997"
Its worth printing the article to have it handy in the shop.
http://www.murphyair.com/support/tocproto.htm
Happy riveting
Jim R254
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[Tim Carter]

The rivets are not MS rivets. They are Avex-style, made by Mattic
Industries in Surrey, BC, Canada. A very good product and company as far as
I can tell.

If you can't find a lead to Mattic to get their product sheets, then let me
know and I'll dig up the info.

Also, any Avex rivet that works diameter and grip wise should work just as
well, and you can get them from A/C Spruce or Wicks A/C Supply.

Tim

-----Original Message-----
From: T L McClary [mailto:tlmcclary@juno.com]
Sent: Monday, March 20, 2000 4:17 AM
To: murphy-rebel@dcsol.com
Subject: Rivets


Has anyone put together a cross reference of Murphy part number to MS /
industry standard part numbers for the rivets Murphy is supplying with
their kits?

With the discussion and recommendations on the list a couple of weeks ago
on rivet length for the rivets used in the aileron assembly offset, I
thought a cross reference would be a nice starting point for us beginners
in trying to find the correct shorter rivets.

Terry

________________________________________________________________
YOU'RE PAYING TOO MUCH FOR THE INTERNET!
Juno now offers FREE Internet Access!
Try it today - there's no risk! For your FREE software, visit:
http://dl.www.juno.com/get/tagj.
*----------------------------------------------------*
The Murphy Rebel Builders List is for the discussion
between builders and owners of Murphy Rebel aircraft.
Archives located at:
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[David A. Ricker]

Randy

We have seen the same phenomenon, this occurs when the rivet is pulled hard and
fast with the pneumatic riveter. I would suggest you try reducing the pressure
going to the riveter with a regulator. We are using something like 30 psi if I
recall correctly. We established this by trial and error, it is just above the
point where the riveter will not break the mandrel It also closely simulates
the setting of the rivet obtained with a hand tool.

Now, for the rest of the story. Our local EAA Tech. Advisor was of the opinion
that the rivets pulled "too hard" were not adequately safe and should be
replaced. They are identifyable because they do not have the nice domed shape
with the end of the mandrel nicely gripped by the end of the rivet (and flush
with the end of the barrel), rather the dome may be pulled into the barrel of
the rivet (giving the mandrel sticking out of the outside end as you have seen)
and the barrel may not be symetric, it can bulge toward one side.

While visiting Murphy though I saw some of what I described and they said it
was not a problem. We are approaching it on the side of caution though.

That said, has anyone else looked into this? Any other opinions?

Dave R.

Randy Straeten wrote:

I was putting the leading edge on the ailerons this weekend. When I used
the pneumtic riveter I was having some of the mandrels break off just above
the rivet head. Does anyone know why this happens and second is there an
easy way to file the mandrel flush with the head

Randy

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--
David A. Ricker P. Eng.
DARTEC Engineering Inc.
3 Tamarac Drive
Fall River, Nova Scotia
Canada, B2T 1E8
ricker@dbis.ns.ca
Ph. 902-860-0256


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[Randy Straeten]

I was putting the leading edge on the ailerons this weekend. When I used
the pneumtic riveter I was having some of the mandrels break off just above
the rivet head. Does anyone know why this happens and second is there an
easy way to file the mandrel flush with the head

Randy

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[LisaFly99]

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[LisaFly99]

Randy
I had the same problem with some supposed avex rivets that I ordered from one
of the large aircraft supply houses. Called MAM and ordered more rivets from
them. And the problem went away. I think that some batches of rivets have the
mandrel to hardened. Also check the jaws of you're rivet gun for a burr, that
could apply more pressure on one spot.
Phil&Lisa Smith #460 N414D
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[Fred Darnell]

It seems to me that it happens when riveting two thin sheets. I can't recall
it ever occurring any other time. It struck me that it was more a result of
the thinness of the material (and thus the rivet being more fully pulled or
compressed) than anything else.

-----Original Message-----
From: LisaFly99@aol.com [mailto:LisaFly99@aol.com]
Sent: Tuesday, March 21, 2000 3:50 PM
To: murphy-rebel@dcsol.com
Subject: Re: Rivets


Randy
I had the same problem with some supposed avex rivets that I ordered from
one
of the large aircraft supply houses. Called MAM and ordered more rivets from
them. And the problem went away. I think that some batches of rivets have
the
mandrel to hardened. Also check the jaws of you're rivet gun for a burr,
that
could apply more pressure on one spot.
Phil&Lisa Smith #460 N414D
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[klehman]

Randy

I have only seen that problem on maybe one out of 40 rivets so I just get them
with a small file or a dremel tool. I use anywhere between 70 to 120 psi.
However I now have a second puller that pulls much harder than the one I have
been using so perhaps I'll drop the pressure a bit. If the hole in the puller is
larger than the diameter of the mandrel, it will also pull aluminum into it and
leave a burr on the rivet head. Trouble is with a tight fit the darn mandrels
don't necessarily fall out of the puller by themselves. If you tested your
rivets, I would not be surprised if the ones with the mandrel poking through are
stronger, as the mandrel would tend to reinforce the rivet in shear. Maybe not
as strong in tension but shear is more important.

Also I have only used MAM's rivets or British made avex. These are available
from Avdel at about cdn$45. per thousand but the part number is slightly
different from what you will find on their website. For protruding head I use
1661-0410, for countersunk 1604-0412. I believe these are stocked because Zenith
Aircraft will only use the British made rivets.

Ken

Randy Straeten wrote:

I was putting the leading edge on the ailerons this weekend. When I used
the pneumtic riveter I was having some of the mandrels break off just above
the rivet head. Does anyone know why this happens and second is there an
easy way to file the mandrel flush with the head

Randy

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[Wayne G. O'Shea]

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the list murphy-rebel@dcsol.com at 17:13:30 on 21 Mar 2000.
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Randy, David and ALL,

I never had this problem with the rivets MAM was supplying, that came from
MATTICK in B.C. The last couple of years MAM has switched to rivets from
RIVET "R" US (or something like that with HDQT's in the vicinity of
Cambridge, Ontario) These are distinguishable because they have "gold"
dichromated mandrels as opposed to aluminum coloured steel mandrels from
Mattick.

Mattick rivets were nice to work with, they went in the holes easier and
maybe one in 500 would break "proud"! (TRUST me, I installed over 70,000 of
them before they switched!) This new suppliers rivets are absolute ###**&%
bears to get in the holes, due to oversized flutes on the sides. If you are
not careful, you will damage thin parts from pushing the rivets into place
with the gun. (the latest batch I have for the SR wings especially as you
can't get them in by hand!) When riveting .020/.025 ribs and .020 skins
together about 1 in 5 break proud and you have to run a flat file along all
the rivets to smooth off. They work fine on grips of over .050. They are
obviously designed for a grip length of .050 plus and the notch in the
mandrel (which allows it to break in the first place) is to far up the stem
for our thin sheets. This causes the rivet to break just proud enough to
catch your cloth when trying to clean the chromate slops from the skin.

David, you're a P. Eng, why are you listening to your EAA advisor on rivet
strength. This represents his opinion only and it is an RAA designated
inspector that will have to inspect your work. (unless he carries both
identities like many do!) As far as I'm concerned, along with many others,
hitting them a little harder actually work hardens the head increasing their
strength. (no different than driving solid rivets and forming shop heads) I
would be of the opposite opinion, that if the heads are still highly domed
after pulling, have they actually been pulled sufficiently!(or is there a
small piece of aluminum shaving under the head holding it up) This is why
Chris Heinz of Zenair actually uses a rivet that looks sort of like a C/S
rivet and the pneumatic puller has a cupped face like a solid rivet setter.
This forms and strengthens the head when pulled, into a dome style head.
Maybe your tech advisor is use to seeing Zenairs go together with pull
rivets, as they do have a higher "domed" shape to them when pulled, than
ours do.

As always, just my 2 cents Canadian!
Wayne G. O'Shea - Rebel 243R and various others!
www.irishfield.on.ca



-----Original Message-----
From: Randy Straeten <randy@w5.net>
To: Murphy Rebel Builders List <murphy-rebel@dcsol.com>
Date: Tuesday, March 21, 2000 2:30 PM
Subject: Re: Rivets

I was putting the leading edge on the ailerons this weekend. When I used
the pneumtic riveter I was having some of the mandrels break off just above
the rivet head. Does anyone know why this happens and second is there an
easy way to file the mandrel flush with the head

Randy

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[klehman]

FWIW I've only seen the older Mattituck rivets from MAM. The Avdel avex numbers
I mentioned are identical to those.
Ken

"Wayne G. O'Shea" wrote:

Randy, David and ALL,
I never had this problem with the rivets MAM was supplying, that came from
MATTICK in B.C. The last couple of years MAM has switched to rivets from
RIVET "R" US (or something like that with HDQT's in the vicinity of
Cambridge, Ontario) These are distinguishable because they have "gold"
dichromated mandrels as opposed to aluminum coloured steel mandrels from
Mattick.

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[David A. Ricker]

Wayne

The rivets I have are from Rivets Unlimited and have the yellow zinc plated
mandrels so this is a starting point and indeed they are "not so easy" to drop
into the holes.

As far as my qualification as a P.Eng. (Mechanical) vs the EAA tech advisor on
determining what is right about this issue, I have to balance my qualification
and experience off against his experience in his position. I am of the habit of
forming an opinion based on the information I have available and applying my
background to made a decision on the way to proceed so his opinion is factored
in.

OK, on to pulling the rivet. I think my description of the "dome" may have
mislead you, the dome I was referring to was the dome of the end of the mandrel
not the "head" of the rivet. What I was referring to was the way the rounded
end of the mandrel is gripped by the end of the barrel of the rivet when it is
pulled. As I understand it, when the rivet is pulled "correctly", the (rounded
= domed) end of the mandrel is trapped in the end of the rivet because it is
pulled slightly into the barrel and the edges of the barrel pull in over it
slightly. Retaining the mandrel end this way ensures that the joint has high
shear strength. In the case of the rivet being pulled "too far" the mandrel
remains inside the barrel but since it is pulled deeper into the rivet it
stretches the barrel somewhat bell shaped and not so strongly holding the
mandrel. This also gives a suspect looking back to the rivet and this is what
the T.A. picked up on. I have found the mandrel easy to push back so that the
rivet can be drilles out and I have suspicion that they could easily work loose
with normal flying vibrations lowering strength.

On the theory that pulling the rivets "fast & hard" or using a domed mandrel to
work harden them, I have to be suspicious. On the first point, I suspect that
the manufacturer has chosen the alloy and hardening state of the aluminum to be
ideal for the "normal" installation procedure (would be interesting to have the
opinion of Avdel on what the recommended procedure is) and anything that would
work harden them more than the design criteria would be detrimental since they
would be less ductile (read brittle) and less able to absorb abuse from
occasional overloading. An overloaded rivet which is more ductile will yield
slightly keeping stress lower than one that is harder but less ductile, the
harder rivet would be more likely to fracture than yield. As for the cupped
riveter nose insert, I have not previously heard of this and if Chris Heinz
believes in it I won't argue with him but it sounds to me like another case of
using the rivet outside the manufacturer's design criteria. I would be
concerned that "doming" the head would leave a void under the head that would
let the barrel to dome intersection work and eventually work harden until it
cracks.

Your assumption on the EAA T.A. and the AIRABA (OK, I don't recall the new name)
are closely linked is correct. I am told these two individuals work very
closely in our EAA Chapter so the opinion of one will have a bearing on the
other. In the club there are perhaps 10 aluminum airplanes, 3 rebels, 3 - 5 RVs
and a couple of Zenairs so I suspect that type experience is not such a big
issue with the AIRABA but the TA is an RV builder so that may influence the
opinion.

OK, back to you, does this make sense to those with more applied experience?

Well, that is about it, I had better get to work since this airplane talk
doesn't pay too well.


Dave R.



Wayne G. O'Shea wrote:

Randy, David and ALL,

I never had this problem with the rivets MAM was supplying, that came from
MATTICK in B.C. The last couple of years MAM has switched to rivets from
RIVET "R" US (or something like that with HDQT's in the vicinity of
Cambridge, Ontario) These are distinguishable because they have "gold"
dichromated mandrels as opposed to aluminum coloured steel mandrels from
Mattick.

Mattick rivets were nice to work with, they went in the holes easier and
maybe one in 500 would break "proud"! (TRUST me, I installed over 70,000 of
them before they switched!) This new suppliers rivets are absolute ###**&%
bears to get in the holes, due to oversized flutes on the sides. If you are
not careful, you will damage thin parts from pushing the rivets into place
with the gun. (the latest batch I have for the SR wings especially as you
can't get them in by hand!) When riveting .020/.025 ribs and .020 skins
together about 1 in 5 break proud and you have to run a flat file along all
the rivets to smooth off. They work fine on grips of over .050. They are
obviously designed for a grip length of .050 plus and the notch in the
mandrel (which allows it to break in the first place) is to far up the stem
for our thin sheets. This causes the rivet to break just proud enough to
catch your cloth when trying to clean the chromate slops from the skin.

David, you're a P. Eng, why are you listening to your EAA advisor on rivet
strength. This represents his opinion only and it is an RAA designated
inspector that will have to inspect your work. (unless he carries both
identities like many do!) As far as I'm concerned, along with many others,
hitting them a little harder actually work hardens the head increasing their
strength. (no different than driving solid rivets and forming shop heads) I
would be of the opposite opinion, that if the heads are still highly domed
after pulling, have they actually been pulled sufficiently!(or is there a
small piece of aluminum shaving under the head holding it up) This is why
Chris Heinz of Zenair actually uses a rivet that looks sort of like a C/S
rivet and the pneumatic puller has a cupped face like a solid rivet setter.
This forms and strengthens the head when pulled, into a dome style head.
Maybe your tech advisor is use to seeing Zenairs go together with pull
rivets, as they do have a higher "domed" shape to them when pulled, than
ours do.

As always, just my 2 cents Canadian!
Wayne G. O'Shea - Rebel 243R and various others!
www.irishfield.on.ca

-----Original Message-----
From: Randy Straeten <randy@w5.net>
To: Murphy Rebel Builders List <murphy-rebel@dcsol.com>
Date: Tuesday, March 21, 2000 2:30 PM
Subject: Re: Rivets

I was putting the leading edge on the ailerons this weekend. When I used
the pneumtic riveter I was having some of the mandrels break off just above
the rivet head. Does anyone know why this happens and second is there an
easy way to file the mandrel flush with the head

Randy

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between builders and owners of Murphy Rebel aircraft.
Archives located at:
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*----------------------------------------------------*

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--
David A. Ricker P. Eng.
DARTEC Engineering Inc.
3 Tamarac Drive
Fall River, Nova Scotia
Canada, B2T 1E8
ricker@dbis.ns.ca
Ph. 902-860-0256


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[McClary, Terry (GEAE)]

David and Wayne,

I read Wayne's response last evening and then David's this morning on work
hardening the rivets. Wayne, I'm not certain that comparing a solid rivet with
a break stem rivet is a good comparison.

In a solid rivet the rivet manufacturer forms one head and you work a mass of
material to form the head. The stresses are distributed through the mass and
yes, I agree, the deformation process work hardens the mass.

In a break stem rivet the head is preformed by the rivet manufacturer by
deforming a thin wall tube. In my mind, the normal process expands the tube
body to fill a hole by drawing a mandrel towards a fixed head. During the
normal process the stresses are imposed in the tube body and not so much the
head. If you work the head you have to be concerned about the stresses that you
have imposed in the radius of the thin wall tube, i.e. the radius between the
tube and head when the head was formed. Granted in a good design most of the
stress in the rivet is in shear and not tension. But, if you have made the
radius brittle by work hardening in, are you setting yourself up for premature
failure in tension?

I think the difference is distributing the work hardening stresses through a
mass of material versus a thin wall tube.

I have read Chris Heinz's article about having a contour ground into his rivet
puller so that it domes the head. At that time I didn't consider the things you
two have brought up. I will say that in one of Chris's articles he states that
he only buys rivets from one source and then he conducts pull tests on a
quantity for quality assurance. That's a good thing and maybe MAM should
consider doing the same.

Terry



-----Original Message-----
From: David A. Ricker [mailto:ricker@dbis.ns.ca]
Sent: Wednesday, March 22, 2000 12:51 PM
To: (Murphy Rebel Builders List)
Subject: Re: Rivets


Wayne

The rivets I have are from Rivets Unlimited and have the yellow zinc plated
mandrels so this is a starting point and indeed they are "not so easy" to drop
into the holes.

As far as my qualification as a P.Eng. (Mechanical) vs the EAA tech advisor on
determining what is right about this issue, I have to balance my qualification
and experience off against his experience in his position. I am of the habit of
forming an opinion based on the information I have available and applying my
background to made a decision on the way to proceed so his opinion is factored
in.

OK, on to pulling the rivet. I think my description of the "dome" may have
mislead you, the dome I was referring to was the dome of the end of the mandrel
not the "head" of the rivet. What I was referring to was the way the rounded
end of the mandrel is gripped by the end of the barrel of the rivet when it is
pulled. As I understand it, when the rivet is pulled "correctly", the (rounded
= domed) end of the mandrel is trapped in the end of the rivet because it is
pulled slightly into the barrel and the edges of the barrel pull in over it
slightly. Retaining the mandrel end this way ensures that the joint has high
shear strength. In the case of the rivet being pulled "too far" the mandrel
remains inside the barrel but since it is pulled deeper into the rivet it
stretches the barrel somewhat bell shaped and not so strongly holding the
mandrel. This also gives a suspect looking back to the rivet and this is what
the T.A. picked up on. I have found the mandrel easy to push back so that the
rivet can be drilles out and I have suspicion that they could easily work loose
with normal flying vibrations lowering strength.

On the theory that pulling the rivets "fast & hard" or using a domed mandrel to
work harden them, I have to be suspicious. On the first point, I suspect that
the manufacturer has chosen the alloy and hardening state of the aluminum to be
ideal for the "normal" installation procedure (would be interesting to have the
opinion of Avdel on what the recommended procedure is) and anything that would
work harden them more than the design criteria would be detrimental since they
would be less ductile (read brittle) and less able to absorb abuse from
occasional overloading. An overloaded rivet which is more ductile will yield
slightly keeping stress lower than one that is harder but less ductile, the
harder rivet would be more likely to fracture than yield. As for the cupped
riveter nose insert, I have not previously heard of this and if Chris Heinz
believes in it I won't argue with him but it sounds to me like another case of
using the rivet outside the manufacturer's design criteria. I would be
concerned that "doming" the head would leave a void under the head that would
let the barrel to dome intersection work and eventually work harden until it
cracks.

Your assumption on the EAA T.A. and the AIRABA (OK, I don't recall the new name)
are closely linked is correct. I am told these two individuals work very
closely in our EAA Chapter so the opinion of one will have a bearing on the
other. In the club there are perhaps 10 aluminum airplanes, 3 rebels, 3 - 5 RVs
and a couple of Zenairs so I suspect that type experience is not such a big
issue with the AIRABA but the TA is an RV builder so that may influence the
opinion.

OK, back to you, does this make sense to those with more applied experience?

Well, that is about it, I had better get to work since this airplane talk
doesn't pay too well.


Dave R.



Wayne G. O'Shea wrote:

Randy, David and ALL,

I never had this problem with the rivets MAM was supplying, that came from
MATTICK in B.C. The last couple of years MAM has switched to rivets from
RIVET "R" US (or something like that with HDQT's in the vicinity of
Cambridge, Ontario) These are distinguishable because they have "gold"
dichromated mandrels as opposed to aluminum coloured steel mandrels from
Mattick.

Mattick rivets were nice to work with, they went in the holes easier and
maybe one in 500 would break "proud"! (TRUST me, I installed over 70,000 of
them before they switched!) This new suppliers rivets are absolute ###**&%
bears to get in the holes, due to oversized flutes on the sides. If you are
not careful, you will damage thin parts from pushing the rivets into place
with the gun. (the latest batch I have for the SR wings especially as you
can't get them in by hand!) When riveting .020/.025 ribs and .020 skins
together about 1 in 5 break proud and you have to run a flat file along all
the rivets to smooth off. They work fine on grips of over .050. They are
obviously designed for a grip length of .050 plus and the notch in the
mandrel (which allows it to break in the first place) is to far up the stem
for our thin sheets. This causes the rivet to break just proud enough to
catch your cloth when trying to clean the chromate slops from the skin.

David, you're a P. Eng, why are you listening to your EAA advisor on rivet
strength. This represents his opinion only and it is an RAA designated
inspector that will have to inspect your work. (unless he carries both
identities like many do!) As far as I'm concerned, along with many others,
hitting them a little harder actually work hardens the head increasing their
strength. (no different than driving solid rivets and forming shop heads) I
would be of the opposite opinion, that if the heads are still highly domed
after pulling, have they actually been pulled sufficiently!(or is there a
small piece of aluminum shaving under the head holding it up) This is why
Chris Heinz of Zenair actually uses a rivet that looks sort of like a C/S
rivet and the pneumatic puller has a cupped face like a solid rivet setter.
This forms and strengthens the head when pulled, into a dome style head.
Maybe your tech advisor is use to seeing Zenairs go together with pull
rivets, as they do have a higher "domed" shape to them when pulled, than
ours do.

As always, just my 2 cents Canadian!
Wayne G. O'Shea - Rebel 243R and various others!
www.irishfield.on.ca

-----Original Message-----
From: Randy Straeten <randy@w5.net>
To: Murphy Rebel Builders List <murphy-rebel@dcsol.com>
Date: Tuesday, March 21, 2000 2:30 PM
Subject: Re: Rivets

I was putting the leading edge on the ailerons this weekend. When I used
the pneumtic riveter I was having some of the mandrels break off just above
the rivet head. Does anyone know why this happens and second is there an
easy way to file the mandrel flush with the head

Randy

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--
David A. Ricker P. Eng.
DARTEC Engineering Inc.
3 Tamarac Drive
Fall River, Nova Scotia
Canada, B2T 1E8
ricker@dbis.ns.ca
Ph. 902-860-0256


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[klehman]

Further to the recent discussion on short rivets I got annoyed at one particular
rivet today so I chucked its mandrel in the old lathe and machined about half
the rivet length away. Darned if it didn't work. Tried it on RV-4410's and on
the countersunk rivets. It probably weakens the rivet but it's better than no
rivet in the hole. Thought someone might get a chuckle out of this....
Ken

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[rebelair]

Hi Ken

I can already believe there is anything left if you machine 'half of it
away'. Do you mean that you shortened the rivet or reduced the diameter, I
assume the former? Great idea as I know, sometimes, nothing seems to fit &
to may have to start a rivet on an angle until the mandrel pulls up enough
to allow you to continue pulling perpendicular to the surface.

Regards

Brian #328R


PS When I are going to see your airplane up there. It must be getting very
close. This would be another great place for a builder's visit, don't you
think?

B

-----Original Message-----
From: klehman@albedo.net [mailto:klehman@albedo.net]
Sent: Tuesday, April 18, 2000 10:32 PM
To: Murphy Rebel
Subject: Re: Rivets


Further to the recent discussion on short rivets I got annoyed at one
particular
rivet today so I chucked its mandrel in the old lathe and machined about
half
the rivet length away. Darned if it didn't work. Tried it on RV-4410's and
on
the countersunk rivets. It probably weakens the rivet but it's better than
no
rivet in the hole. Thought someone might get a chuckle out of this....
Ken

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Archives located at:
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--------*

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Archives located at:
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