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Rivets

Converted from Wildcat! database. (read only)
klehman

Rivets

Post by klehman » Fri Feb 17, 2012 5:46 pm

Hi Brian

Yes I shortened the rivet. One was for a top skin to rear spar hole that was
precisely lined up with the bolt that holds the flaperon bracket. "Murphy's
Laws" according to my wife.

I am definately near the 90% to go stage with only a couple more years of work.
At Daryl's suggestion I replaced a few rivets at the rear of the tank skin with
5/32" ones to fix my skin alignment problem. The wings are now finished except
for the pitot tube. I have MAM's wing mounted unit which has one static hole
that can either be on the top or bottom of the tube. Neither orientation seems
right so am thinking of drilling two more on the sides and maybe plugging the
existing hole. Or I could use a separate static vent.

The floor is drilled and ready but not in the fuselage at this point so it is
perhaps a good point to see the fuselage if anyone wants to drop by. (near
Guelph - About 35 miles West of Toronto International Airport). I don't have the
space for more than about 2 visitors at a time though. (people brave enough to
enter the basement have to walk sideways) The floor should rivet in quickly now
that the weather is warming up and then it's back to work on the controls.

Ken

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Bob Patterson

Rivets

Post by Bob Patterson » Fri Feb 17, 2012 5:46 pm

Ken,
I wouldn't worry too much about the static hole - you could put
it on the bottom, and add another on the side, though. Many builders
don't use the pitot static, just useing cockpit ambient. While static
can introduce errors, the largest errors on the Rebel seem to be
caused by small diameter pitots, which are sensitive to variations
in angle of attack, or are mounted at odd angles to start with.

I'm surprised your MAM pitot tube has a static hole that is
<connected> - many early ones didn't ! Something for everyone to check ....

Airspeed indicator errors are very common in Rebels because
of the large range of angles of attack that they will fly at, especially
at the low end. In early test flying, it is important to establish the
<indicated> stall speed, just for reference & safety's sake. You can
refine the accuracy of the indicator later in the program.

.....bobp

-----------------------------orig.--------------------------------------------
At 09:24 AM 4/19/00 -0400, you wrote:
Hi Brian

Yes I shortened the rivet. One was for a top skin to rear spar hole that was
precisely lined up with the bolt that holds the flaperon bracket. "Murphy's
Laws" according to my wife.

I am definately near the 90% to go stage with only a couple more years of work.
At Daryl's suggestion I replaced a few rivets at the rear of the tank skin with
5/32" ones to fix my skin alignment problem. The wings are now finished except
for the pitot tube. I have MAM's wing mounted unit which has one static hole
that can either be on the top or bottom of the tube. Neither orientation seems
right so am thinking of drilling two more on the sides and maybe plugging the
existing hole. Or I could use a separate static vent.

The floor is drilled and ready but not in the fuselage at this point so it is
perhaps a good point to see the fuselage if anyone wants to drop by. (near
Guelph - About 35 miles West of Toronto International Airport). I don't
have the
space for more than about 2 visitors at a time though. (people brave enough to
enter the basement have to walk sideways) The floor should rivet in
quickly now
that the weather is warming up and then it's back to work on the controls.

Ken

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Mnleber

Rivets

Post by Mnleber » Fri Feb 17, 2012 5:56 pm

I haven't seen anything on here about rivets. Is anyone else but Randy and I
having problems. The rivets supplied with the kit are breaking the mandrels
leaving anywhere from a 1/16" to 1/2" sticking out, which then has to be
filed or ground flat. Very messy and veeeeeery time consuming. MAM, Brian
Godden says they are doing something about it but so far nothing. Randy found
a supplier, Textron, who has avex rivets that work fine, but with over 20000
riviets in the kit I can't afford to replace them myself and we are getting
to the point of being held up (i.e slowing the project down!)

Mike Le Ber R683
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Wayne G. O'Shea

Rivets

Post by Wayne G. O'Shea » Fri Feb 17, 2012 5:56 pm

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Your following message has been delivered to the 154 members of
the list murphy-rebel@dcsol.com at 23:18:43 on 29 May 2000.
--------------------------------------------------------------------------


Yes we have discussed this before! The rivets from Rivets Unlimited? are
very hard to put in the holes and the mandrels pull "proud" on thin sections
due to their stem notch being too high on the mandrel. The older kits had
rivets from Mattic in B.C. and they worked great. Both brands do have the
odd "bad" mandrel that breaks about 1/2" up though. Try a little less air
pressure to pull a nice "bulb" on the blind side of the rivets and not a
deformed "bulb". It will help a bit, but I did a set of SR2500 wings
recently with the newer rivets and had to run a flat file over the entire
structures rivet rows! MInor pain in the ass, compared to the sore fingers
trying to get the oversized rivets in the holes in the first place!!!

Regards,
Wayne G. O'Shea
www.irishfield.on.ca

-----Original Message-----
From: Mnleber@aol.com <Mnleber@aol.com>
To: murphy-rebel@dcsol.com <murphy-rebel@dcsol.com>
Date: Monday, May 29, 2000 10:59 PM
Subject: Rivets

I haven't seen anything on here about rivets. Is anyone else but Randy and
I
having problems. The rivets supplied with the kit are breaking the mandrels
leaving anywhere from a 1/16" to 1/2" sticking out, which then has to be
filed or ground flat. Very messy and veeeeeery time consuming. MAM, Brian
Godden says they are doing something about it but so far nothing. Randy
found
a supplier, Textron, who has avex rivets that work fine, but with over
20000
riviets in the kit I can't afford to replace them myself and we are getting
to the point of being held up (i.e slowing the project down!)

Mike Le Ber R683
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Roger & Alice Hoffman

Rivets

Post by Roger & Alice Hoffman » Fri Feb 17, 2012 5:56 pm

Mike,

YES!! I am having the same problem with the supplied RV-1410 rivets. A BIG
percentage of those I have pulled so far, break usually not more than 1/16th
inch above the head of the rivet.

This occurs with either my pneumatic or manual squeeze riveter.

There was some previous discussion on this list in this regard, but I
searched the archives this morning and could not find it. I do remember
Wayne O'Shea (I think?) advising to try adjusting the air pressure of the
pneumatic riveter down.

I tried that, but without any success. I have turned it down to the point
where it will pull but not break the mandrel (about 25psi I recall). Then I
incrementally increased the air pressure to the point (30-35psi) where it
would pull, pause slightly, then break, but I'm still getting a large
percentage of mandrel 'stumps'.

I've also tried incremental air pressures throughout the range to the max
90psi for this riveter. It just has not made any difference in my case.

I noticed you serial number is #683. Mine is #687. Perhaps we got a bad
batch??

Perhaps if we could send a list of all the builders having this problem, MAM
would become more inclined to move on it??

Roger #687R
Eugene, OR USA

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David A. Ricker

Rivets

Post by David A. Ricker » Fri Feb 17, 2012 5:56 pm

Mike

If you look back a few weeks in the archive you will find a discussion on the topic
(although I couldn't access the archive today...). As we have seen, there appears to be
some descrepancy between the performance of different manufacturers of the rivets with
the Rivets Unlimited version being more likely to have the mandrel pull up too far.

When I spoke with them they recomended to pull the rivets at a low pressure so that the
"bulb" forms evenly. I have lowered the pressure until the mandrel is loaded just enough
to break which simulates pulling it by hand, this at about 30 psi on my air riveter. I
do note though that even this doesn't always produce a nicely formed rivet though.

If you hear more from Murphy pls let us know.

Dave R.


Mnleber@aol.com wrote:
I haven't seen anything on here about rivets. Is anyone else but Randy and I
having problems. The rivets supplied with the kit are breaking the mandrels
leaving anywhere from a 1/16" to 1/2" sticking out, which then has to be
filed or ground flat. Very messy and veeeeeery time consuming. MAM, Brian
Godden says they are doing something about it but so far nothing. Randy found
a supplier, Textron, who has avex rivets that work fine, but with over 20000
riviets in the kit I can't afford to replace them myself and we are getting
to the point of being held up (i.e slowing the project down!)

Mike Le Ber R683
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--
David A. Ricker P. Eng.
DARTEC Engineering Inc.
Nova Scotia
Canada
ricker@dbis.ns.ca



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REBEL112R

Rivets

Post by REBEL112R » Fri Feb 17, 2012 5:56 pm

I would say that the problem is the rivets. If the material you were
rivetting were to thin for the rivet this problem would occur. This is not
the case in your instance. Try rivetting some scrap sections together maybe
.020 thicker and see if the problem goes away. My guess is you might need a
new batch of rivets. My two cents.
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Bob Patterson

rivets

Post by Bob Patterson » Fri Feb 17, 2012 5:56 pm

Hang in there, guys !!! Murphy IS working hard to come up
with a solution !!!! Apparently the RU rep. visited the factory today.

The Rivets Unlimited guys are saying that their rivets are
fine - IF you are joining pieces that are THICKER than .050 ....... (!!)

Anybody out there that can test a few pieces ??? At what
thickness of material DO they work properly ???

<IF> that is true, then they <MAY> replace those rivets needed
to join .045 or less .... (perhaps about half (??) the rivets ?? )

Let's give them some ammunition so the folks at the factory
can work on the RU guys ....

THANKS !!!
.....bobp

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Wayne G. O'Shea

rivets

Post by Wayne G. O'Shea » Fri Feb 17, 2012 5:56 pm

--------------------------------------------------------------------------
Your following message has been delivered to the 156 members of
the list murphy-rebel@dcsol.com at 10:10:14 on 31 May 2000.
--------------------------------------------------------------------------


BOB, Here's my testimonial!

I have pulled in excess of 100,000 rivets building Murphy Products since
1993. I had very few problems using the RV1410 rivets that were supplied
through Mattic of B.C. Recently MAM switched to RV1410 rivets supplied
through Rivets Unlimited and they are absolutely terrible to work with. You
can not even clean off your finished wings with a shop cloth, as it will rip
to shreds as you run it across the surface. You must take a flat file and
run it across the rivet heads, being careful to not gouge the wing skin (or
your hand on the mandrels) or take too much off the rivets heads in an
attempt to remove the proud mandrel "breaks"!

Rivets Unlimited's statement that their rivets are fine for anything that
has a grip of 50 thou or more should put the ball firmly in their court and
they should be held liable to replace everyone's rivets. A 50thou working
thickness (grip) isn't useful ANYWHERE on a Rebel (for the RV1410's) or most
places on the SR2500, so why doesn't MAM demand that Rivets Unlimited
replace everyone's rivets <IF> the original MAM Specified order was a grip
of 32 thou and up as it should have been. Rudder skin to ribs are about 36
thou. Rivets Unlimited's don't work properly here! Even on the SR2500 where
the stringers are .062 and the skin is .020 = 82 thou, they still pull proud
about 10% of the time. On the ribs to main wing skins they pull proud
everywhere and this thickness is 40 thou, 45 thou or 52 thou depending on
the rib location. They also pull proud on the leading edges of the SR and
these are 52 thou and 57 thou grips.

The Rivets Unlimited's rivets are also "fluted" too much oversize and can't
be inserted into the holes (#30) by hand! They must be forced in with the
gun and on thin sheet this is going to cause some dents and rivets that get
pulled before they are seated. This is a real pain that every rivet must be
forced in place with the gun and this slows the riveting progress
astronomically, as well as the workers fatigue levels.

If MAM can not come to terms with Rivets Unlimited, they should go back to
Mattic for rivets (if they haven't broke the bridge to them from cutting
them off), as Mattic's rivets worked beautiful. The "yellow" dichromated
mandrels don't mean a thing with the Rivets Unlimited ones anyhow, as when
the mandrel breaks off there is no coating anymore at the break and this is
the area that's exposed!

Hope this helps everyone currently building and stuck in this dilemma and
myself with future orders.

Yours truly,
Wayne G. O'Shea

C.C. Brian Godden - Murphy Aircraft MFG.

-----Original Message-----
From: Bob Patterson <bob.patterson@canrem.com>
To: murphy-rebel@dcsol.com <murphy-rebel@dcsol.com>
Date: Tuesday, May 30, 2000 11:30 PM
Subject: rivets

Hang in there, guys !!! Murphy IS working hard to come up
with a solution !!!! Apparently the RU rep. visited the factory today.

The Rivets Unlimited guys are saying that their rivets are
fine - IF you are joining pieces that are THICKER than .050 ....... (!!)

Anybody out there that can test a few pieces ??? At what
thickness of material DO they work properly ???

<IF> that is true, then they <MAY> replace those rivets needed
to join .045 or less .... (perhaps about half (??) the rivets ?? )

Let's give them some ammunition so the folks at the factory
can work on the RU guys ....

THANKS !!!
.....bobp

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Peter & Monica

rivets

Post by Peter & Monica » Fri Feb 17, 2012 5:56 pm

Wayne has hit the "rivet" on the head!! Everything he said goes double
for us! Having to "pound" the rivets in the holes is awfully hard on
the hands. And then cleaning up, ouch, look out for those mandrels
sticking out!

The whole riveting process has turned out to be time consuming,
frustrating and painful on the hands.

Peter Kopasovic
Monica Piquette
SR003

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MWKlsy

Rivets

Post by MWKlsy » Fri Feb 17, 2012 5:56 pm

Hi:
As I am a person who so far has not purchased a Murphy Rebel or Elite kit,
I am truly amazed of the level of support that is exchanged here. My goal in
a kit is to build an amphibious, Subaru (EJ-22) powered plane. I think one of
these planes would do a superb job. My decision is getting easier by the day.
One of the selling points is the companies stance of using the Avex blind
rivit to ease the construction. I agree..........when they work like they
should. That doesn't seem to be the case at the moment, and I plan to hold
off on a purchase until this is resolved. I too would not be a "Happy Camper"
if my new kit were supplied with fasteners that did not perform as advertised.
I have just read a very interesting article written by Chris Heintz. Some
of you have probably already read this. It has some very good information on
blind rivits. The link is:
<A
HREF="http://www.zenithair.com/kit-data/ht-86 ... ">Aircraft Construction,
Riveted Joints (Part 1 of 2)</A>
Oh, yes......one question........please...... Lets see.........20,000
fasteners for the airframe. And how many for the 1800 amphibs? Thanks in
advance.
sincerely,
Michael Kelsey
Lake
Stevens,Wa
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klehman

Rivets

Post by klehman » Fri Feb 17, 2012 5:56 pm

Michael

Think I have about eleven thousand rivets for the 1800 amphib floats. These are
tank or sealed rivets and have not been a problem that I'm aware of. The MAM
factory built floats seem to have amazingly good pricing these days though.

You could probably order the Rebel kit without the rivets rather than delay.
About cdn $48. per thousand from Avdel in Toronto. (about US$32.) Believe
Stanfield NC is the American headquarters but think there are numerous outlets.
www.avdelcherrytextron.com
Ordering without the rivets, or on condition of Avdel/Mattic rivets being
supplied, might speed up a resolution and/or reduce your wait for a kit.

I'm one of several here also hoping to fly with the Ej22 engine.

Ken



MWKlsy@aol.com wrote:
Hi:
As I am a person who so far has not purchased a Murphy Rebel or Elite kit,
I am truly amazed of the level of support that is exchanged here. My goal in
a kit is to build an amphibious, Subaru (EJ-22) powered plane. I think one of
these planes would do a superb job. My decision is getting easier by the day.
One of the selling points is the companies stance of using the Avex blind
rivit to ease the construction. I agree..........when they work like they
should. That doesn't seem to be the case at the moment, and I plan to hold
off on a purchase until this is resolved. I too would not be a "Happy Camper"
if my new kit were supplied with fasteners that did not perform as advertised.
I have just read a very interesting article written by Chris Heintz. Some
of you have probably already read this. It has some very good information on
blind rivits. The link is:
<A
HREF="http://www.zenithair.com/kit-data/ht-86 ... ">Aircraft Construction,
Riveted Joints (Part 1 of 2)</A>
Oh, yes......one question........please...... Lets see.........20,000
fasteners for the airframe. And how many for the 1800 amphibs? Thanks in
advance.
sincerely,
Michael Kelsey
Lake
Stevens,Wa
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David A. Ricker

rivets

Post by David A. Ricker » Fri Feb 17, 2012 5:56 pm

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> Bob
Thanks for your heads up on this and for representing this group (and for sure others!) on this important matter.
OK, here are the results of my quick test of the material thickness vs mandrel sticking out as you referred to in your mail. For a material joined thickness of .049", 2 rivets pulled by air @80 psi, the mandrels were not exposed, one pulled by hand however remained lower in the barrel (further from the flange). Both of the air - pulled rivets exhibited some of the mis-shaping which my EAA tech counsellor did not like while the hand pulled sample was OK. For the other sample with a thicknes of .037", one of the two rivets air pulled had the deformed formation and the mandrel exposed, the hand pulled rivet was OK. The other air pulled rivet set with the mandrel pulled further into the barrel but by eye it is probably OK.
Conclusions: On a statistically insignificant sample, 1) the thinner material appears to promote exposure of the mandrel of an incorrectly formed rivet, 2) Hand pulling the rivets results in acceptable setting. See my comment below about pulling at low pressure.
When MAM looks into the issue of these rivets how about suggesting they not only look into the issue of how these rivets perform with more/less than .050" thickness materials but that they look at the metallurgy of the rivet while they are at it.
What I am referring to is the inconsistency of the rivets to pull "correctly" with the nice neat bulb forming. Following the instructions I got when I called RU about this issue (use lowest air pressure/equivalent to pulling by hand) most of the rivets I install come out more or less OK BUT there are a not insignificant number that I do not consider to meet the "correct" forming description. This is where the mettalurgy aspect comes in.
I suspect that the hardness (roughly correlating to yield strength) of the poorly formed rivets is lower than for the "correctly" forming ones. This could be seen in the rivets which have the mandrels pulling too far. I have seen the "head" of the mandrel extrude the hole in the barrel significantly deeper than was originally formed, pulling the domed head up into the barrel of the rivet (significantly more than what is required to capture it in the "ideal" pulled condition, this would be a few .000") and causing the barrel of the rivet to become deformed and open up like the mouth of a funnel or otherwise deform. It is in these cases that the broken end of the mandrel finishes proud of the outer surface of the flange. I discussed this with MAM when I visited last October and was told it was not an issue although my EAA Tech. Counsellor believes it is........Since our local AIA-ABA (or whatever they are called now) is also part of our EAA group I don't think I will get much of a different opinion from him either.
What I am most concerned about here is that there may be some risk that we do not have an adequate strength of the riveted joint (implying not meeting MAM's design criteria). It would be interesting and informative to have MAM do a test of the RU rivets along with the other "equivalent" suppliers comparing setting "correctness" vs material hardness of the rivet barrel vs joint strength.
My somewhat educated guess would be that there will be a positive correlation between "correct" setting, high material hardness and higher joint strength.
As for the issue of material thickness being joined, is it possible that the .050"+ thickness masks the problem (looking from the outside) because the pulled length of the rivet is longer, keeping the broken mandrel end from pulling up past the flange? Saying it differently, the thickness of the material will define how far the mandrel will travel before stopping. I suspect the mandrel head will (in "incorrect" forming) spread (extrude into) the rivet barrel until it encounters the material being riveted and stop since the force required to spread the hole in the joined material will be much higher than the rivet barrel and the mandrel will break at that point. To say it differently, the barrel will spread "easily" (that is, the mandrel head will enlarge the ID of the rivet barrel) but when you try and force the head through the hole in the material being joined it requires much more force and the mandrel breaks instead. The thickness of the material will determine whether the mandrel broken end will be exposed or not.
Bob, please use your close links to the factory to express these concerns and those voiced by the other builders of this group and beyond to MAM and request that they ensure we are not building components which will have inherent strength concerns. As a follow up from MAM, I believe it would be appropriate that they send us a note (as is done with service bulletins, E-mail is fine and costs less also) advising on the positive or negative results of this rivet issue. My worst case scenario looks like replacing all the presently installed rivets which is not a pleasant thought. I would appreciate if you would, on behalf of this group carry these concerns to MAM in lieu of each of us doing so individually (I have not pursued it further with them so far and believe a single representation from a significant group is preferred).
I hope this is really not a safety issue but I think it is worth having MAM clear the air based on recent discussion here in this forum.
Thank you

David Ricker


Bob Patterson wrote:
Hang in there, guys !!! Murphy IS working hard to come up
with a solution !!!! Apparently the RU rep. visited the factory today.
The Rivets Unlimited guys are saying that their rivets are
fine - IF you are joining pieces that are THICKER than .050 ....... (!!)
Anybody out there that can test a few pieces ??? At what
thickness of material DO they work properly ???
<IF> that is true, then they <MAY> replace those rivets needed
to join .045 or less .... (perhaps about half (??) the rivets ?? )
Let's give them some ammunition so the folks at the factory
can work on the RU guys ....
THANKS !!!
.....bobp
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David A. Ricker P. Eng.
DARTEC Engineering Inc.
Nova Scotia
Canada
ricker@dbis.ns.ca

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Mnleber

Rivets

Post by Mnleber » Fri Feb 17, 2012 5:56 pm

Bob, I read your comments about MAM working on the problem. They definitely
are a problem on the thinner material i.e. 2 pieces of .020 material but they
also don't work much better on the thicker material such as when I mounts the
control horns and end plates on the flaperons and ended up having to file 3
of every 10 riviets. In this case not only did I get the 1/16" stub I also
had a number that left a good 1/2" or better. Again keep in mind I'm using a
hand rivetter and not an air gun. Also keep in mind I have just finished
using the same number of textron rivets and not had one problem on any
thickness. So far problems have come from R682, R683, and R687. Anyway RU
wants to slice it, they have an inferior and defective product and it should
be replaced in total not in some token way "goodwill" type "gesture". If MAM
needs my support they've got it. If RU wants a demo first hand they are
welcome to come to my place for a demo. Ask them to bring their own file.
Mine will probably be in use!!!!! We can have a side by side comparison with
their competition's product.

Hope this helps.

Mike Le Ber #R683

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Roger & Alice Hoffman

Rivets

Post by Roger & Alice Hoffman » Fri Feb 17, 2012 5:56 pm

This was posted on MAM's website today:
------------
TECHNICAL DEPARTMENT, 1st. June 2000

Statement on problems encountered with blind rivets supplied by "Rivets
Unlimited".
It has now become clear that the blind "Avex type" rivet we have been
supplying for several years has run into some production and quality control
problems.
This rivet can be identified by the Cadmium (gold) plated mandrel, in
contrast to the Phosphorus (grey) mandrel of the original Avex from Avdel.
Many kits have been completed with this rivet in question over a period of
some years, encountering no problems, and indeed the problem is sporadic
over a number of recent kits, so we hope it is clear that Murphy supplied
these rivets in good faith.
The problem must stem from the manufacturer's production techniques, and
leads to the mandrel of the 1/8" diameter rivet breaking off proud of the
head, in grip
ranges below 0.045".
It has taken some time to resolve this problem because of our total lack of
satisfaction from "Rivets Unlimited".
Therefore, in the interests of our valued customers, Murphy Aircraft will
try to provide what will be an acceptable solution:
1/ All kits shipped since 15 May 2000 have ONLY Avex rivets included in the
kit, and this will remain the case for all future kits.
2/ Customers are advised to use the "Rivets Unlimited" rivets in areas of
0.045" or more thickness, or in concealed areas where a slightly proud
mandrel is not a
problem.
Murphy Aircraft is satisfied that there are no structural implications in
using the "Rivets Unlimited" product.
3/ Would customers who ARE encountering problems please contact the
Technical department for further information, giving their aircraft type and
serial number.

We apologize for the inconvenience, but hope that customers will understand
the quality control problems encountered with these rivets were factors
beyond our
control.
-------------

Thank You Murphy Aircraft!

R. Hoffman #687R
Eugene, OR

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