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Aluminium Pop Rivets in Steel Car body

12/25/2009 1:02 AM

Can anyone tell me if there is a reason not to use Aluminium Pop Rivets to hold trim clips onto a Steel car body? Some appear to recommend only using steel/steel Pop Rivets with steel panels but Aluminium bodied rivets with Steel posts are way easier to come by. If I use neutral cure silicon when applying the clips can I use Aluminium rivets without fear of corrosion due to electrolysis?

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#1

Re: Aluminium Pop Rivets in Steel Car body

12/25/2009 1:23 AM

You've answered your own question... Aluminum and steel don't mix!!! Also, electrolysis is actually helped by a "partial" cutoff of oxygen. So, the silicon may just make it worse.

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#14
In reply to #1

Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 12:06 PM

For what its worth this answer is right on the money

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#15
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Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 12:19 PM

If steel pop rivets are used you will have a rust problem in that area long before there would be a problem using aluminium pop rivets.

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#19
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Re: Aluminium Pop Rivets in Steel Car body

12/27/2009 1:35 AM

Manufacturers have used aluminium pop rivets since 1948 in Australia, maybe longer with Austin/Morris and coach builders. It will not rust to the detriment of integrity or appearance.

RRV

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#2

Re: Aluminium Pop Rivets in Steel Car body

12/25/2009 8:18 AM

Carbon steel or stainless pop rivets are readily available, here's a UK source but there must be some in your part of the world.

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#3

Re: Aluminium Pop Rivets in Steel Car body

12/25/2009 11:49 AM

pop rivets are not a good idea on the out side, but if you have to use them steel on steel ONLY a stud welder is how the oe did it NO holes. They dont cost that much

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#4

Re: Aluminium Pop Rivets in Steel Car body

12/25/2009 10:47 PM

No Sir, you can not do that. The "silicon" (or even Sycaflex) will squeeze out and anyway, the bulged stem will always touch the steel. You will have cathalityc corrosion. And even if you use a "mylar" washer, you will have problems with the bulged stem. You need to use Stainless Steel monobolts (rivets who will have the center filled by a "core nail" who brakes at the end of the pop-up job). With these, you won't have water incursion through the normal cheap pop up rivets who leave a hole at the center.

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#5

Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 12:11 AM

corrosion due to electrolysis will occur if there is any contact whatsoever. I would not take the chance. Corrosion occurs rapidly

P E Bobimm

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#6

Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 2:00 AM

G'day,

I know that the other comments are technically true but I have known car bodies that have aluminium pop rivets securing trim et cetera. I've even seen vehicles with rust repair sections riveted in with aluminium pop rivets. They has been there for quite a while too.

If you think about it, I suppose the aluminium rivet will have its own oxide coating any way, thus isolating the two metals.

Ford Australia (and all other manufacturers) rivet their ADR Compliance plates, SIDO plates etc. to the body (in the engine bay) for well 50 years without problems.

I'd suggest to do it and if you want extra insurance, spray with WD40 etc., or coat with a wax.

Royce

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#7

Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 2:06 AM

I agree with what's been said but depending on the use and your location I wouldn't be too concerned. How long do you plan on keeping the car anyways. I have had a stainless steel firewall riveted onto a mild steel frame in my Model A for more than 50 years without any sign of rust and that was with aluminium explosive rivets.

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#8

Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 7:24 AM

Thanks everyone for replies. As usual I am still unconvinced either way except to say I intend to keep the car a long time and it had aluminium pop rivets holding the trim clips on when I removed them for respraying - no sign of corrosion but they had only been there about 12 years.

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#9
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Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 8:25 AM

I would not worry about using aluminium pop rivets, yours have been in for 12 years without a problem so how about 20 years that should be long enough? Use blind rivets and there will be no water leakage through the rivet, Also use a Thioflex type sealant round the rivet prior to setting this will seal unpainted steel round the hole rust wont be a problem. what the others neglected is that the rivet is sacrificial and will protect the steel, but in reality it will be negligible.

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#21
In reply to #8

Re: Aluminium Pop Rivets in Steel Car body

12/27/2009 1:49 AM

Just do it pal, they will last. Check out any old car and the I.D. plates will be popped on.

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#10

Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 8:33 AM

I don't think so because when you squeeze the rivet it will dig into the steel.

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#11
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Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 9:39 AM

Are you replying re my post? if so what is your point?

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#12
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Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 10:36 AM

The aluminum is considerably softer. The steel will diginto it. Not the other way around.

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#13
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Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 10:49 AM

So what has that got to do with anything?

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#16

Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 1:11 PM

Garth;

I inferred that Jim was responding to one or more of the posts that regardless of the type of corrosion inhibitor used between the two dissimilar metals that with one being softer than the other and the deformation of the rivet during installation that the barriers integrity would be lost if not diminished and there for the intended purpose would be for naught.

I would have to concur ( to some extent ) with him. My only correction to him is that as aluminum is the softer of the two it would be the coating ( applied or natural ) on the aluminum that would be at greater risk ( implied ).

I hope he understood better than you did.

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#23
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Re: Aluminium Pop Rivets in Steel Car body

12/27/2009 9:52 AM

I understand perfectly, it is not a barrier to insulate the two parts this would be a stupid proposition for a pop rivet.It is to fill any microscopic voids between the two parts this reduces the chances of moisture ingress between the surfaces and therefore takes away the chance of reaction between the surfaces. Parts of the rivet exposed to the air on iether side of the joint will have little cause for reaction with the steel.

I trust you will understand this.

I should say some people do not appear to appreciate the reactions between disimialer metals, stainless rivets would not rust but the steel would suffer, as I see it it would be easir to replace rivets than steel repairs presumably on a vehical to which the owner would like to keep for a long time. In any case my previous post said any problem would be negligable, if people do not wish to see it that way I cannot help them.

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#17

Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 1:31 PM

Johny;

The corrosive relationship between two dissimilar metals exposed to the atmosphere largely depends on the atmosphere itself.

If you live on the coast then rivets that match the base metal would work better than the aluminum, stainless would probably work best.

If not then I wouldn't really worry too much about it. Who knows maybe you'll want to redo your car again in another twelve years.

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#18

Re: Aluminium Pop Rivets in Steel Car body

12/26/2009 2:59 PM

The reason's name is "Galvanic action between dissimilar metals"

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#20
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Re: Aluminium Pop Rivets in Steel Car body

12/27/2009 1:38 AM

You are forgetting that the aluminium will oxidise as all ally does. Aluminium Oxide is hard, impervious and is a very good barrier protection to corrosion of any type.

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#22
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Re: Aluminium Pop Rivets in Steel Car body

12/27/2009 8:59 AM

Hi

No I didn't forget. In the presence of air, Aluminum oxide forms a white powder. it will leave a gap between the steel and the rivet and will get loose in time. Without the presence of Oxygen, The dissimilar electrical action will take place as long as there's sufficient electrode material, and this is the problem.

electrical connection of Al-Fe is strictly prohibited. You will never find Fe to Al rivets in aviation.

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#25
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Re: Aluminium Pop Rivets in Steel Car body

12/27/2009 10:04 PM

Actually, aluminium oxide is the clear or coloured (anodised) coating that generally stops corrosion. It will only turn white when excessive. As I said, which seems to be ignored, check out and old cars' I.D. plate in the engine bay. In Australia, I have known the alloy SIDO (Ford) plate to be okay after of the rivets. The car has been garaged on the Gold Coast and in Brisbane where it was subject to high humidity. Actually, the only rusty panels that needed replacement were at the other end of the car to where the pop rivets are.

RRV

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#26
In reply to #25

Re: Aluminium Pop Rivets in Steel Car body

12/27/2009 10:19 PM

I know about aluminum oxide and how it eventually stops corroding, but the steel will still corrode. Also, the aluminum oxide coating can grow sort of crunchy-like and lift paint. Furthermore, I've seen a number of cars where the VIN plate inside the passenger compartment shows actual rust over the years... Another steel/aluminum mix.

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#24
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Re: Aluminium Pop Rivets in Steel Car body

12/27/2009 9:48 PM

Do I believe English cars use aluminum rivets in steel? Of course I do! Just like all the other crappy stuff they've incorporated in building cars.

By the way, If the rivet will be visible and there'll be paint over it, you're going to have one funky paint job in the future.

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#27
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Re: Aluminium Pop Rivets in Steel Car body

12/27/2009 11:33 PM

You are demonstrating your ignorance with your comments re English cars. I'm in Australia. Besides, if the seppo cars are so good, why is GM etc in the shit?

By the way, the Compliance Plate, I.D. Plate and SIDO Plate are stamped aluminium and unpainted. This also applied to Seppo imports, Jap. imports, Korean imports, European Imports, South African Imports (BMW etc) and even Russian imports (Lada). All ADR Compliance Plates (required since 1969) have been affixed to the firewall by pop rivets. That plate is an aluminium or stainless (304) stamping but the rivets are alloy. I'm rure even the Yanks had/have something similar. I reasonably sure Ford did with their pre-1972 Galaxies as Ford Australia imported them from the U.S. and they came with a Tank SIDO Plate.

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#28
In reply to #27

Re: Aluminium Pop Rivets in Steel Car body

12/28/2009 2:13 AM

Lucas lights????

Triumph tractor????

"Give an Englishman a piece of metal and he'll do something silly with it."

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#29
In reply to #28

Re: Aluminium Pop Rivets in Steel Car body

12/28/2009 3:22 AM

You seem to be living up to your moniker. I cannot think of many yank cars that were not just a barely controllable marketing exercise for lard arsed automotive ignoramii. Please engage brain before fingers in future.

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#30
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Re: Aluminium Pop Rivets in Steel Car body

12/28/2009 4:14 AM

Oh, lighten up, for Christ's sake!

England produced a whole lot of crap cars that fell apart way fast. I know, I owned them!!! I've been under Triumphs, MGs, Austin Healeys, and other English metal, and the stuff they were using (their technology) was older than the US stuff of the time.

Sure, U.S. cars have their problems (both today and in the past), but at least the pre-computer cars would run, and bits weren't always breaking or breaking off.

OK. So not to single out the English, my Fiat developed a cracked head--no biggie. However, when the mechanic ordered six different "new" heads from the factory, and each arrived with a crack... I mean come on!

The Germans... My uncle was a Mercedes mechanic for thirty years. He always said that Mercedes was his favorite car--not because he'd buy one, but because they produced more work for him than he knew what to do with.

As for my own preferences, if I can't drive a Porsche, then give me Japanese every time! Every Japanese car I've ever owned was a wonderful no-hassle machine.

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#31
In reply to #30

Re: Aluminium Pop Rivets in Steel Car body

12/28/2009 7:00 AM

Maybe you are not familiar with maintenance. I had a Jag which didn't leak oil, a Rover P6 3500 which was great, a Stag which gave no hassle and a FIAT 124 s which never let me down. Evan an Aussie Cortina 6 which, although it required a bit if fiddling, never actually stopped and left me stranded. Actually, the only cars I've needed a tow with have been an Aussie Austin Kimberly (mech fuel pump) and a Holden HJ one tonner (point capacitor on a Sunday)

I always maintain maintenance is the key to satisfying motoring. Jap cars in the past at least have always tended to cater to the yanks when it came to chassis tuning. You know, I've even kept MG (B series) running well. I guess you have to love cars.

I still stand by my comments re the pop rivets and trim. Even the Transport Department (Quidnunc Transport) requires an I.D. plat be rivetted or to a trailer chassis and pop rivets are specified.

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#37
In reply to #31

Re: Aluminium Pop Rivets in Steel Car body

12/29/2009 11:31 PM

You've had great luck, and I agree about the maintenance idea.

Here's a question you might be able to answer for me... I was looking a maybe picking up a Rover because of their reputation and worldwide presence. However, everyone I've talked to says that the new Rovers are now fall apart vehicles. So is this true, and if yes, what happened?

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#38
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Re: Aluminium Pop Rivets in Steel Car body

12/30/2009 5:46 AM

Dunno about the latest, but the models following the SD! were Hondas. Personally, I think the only one to consider is the P6, especially with a 4.4 Aussie P76 motor in them. The SD1 lost the DeDion rear end and it was a simple unitary construction. The P6's could actually drive around (Sollihul) without their panels and had a ripper and unique front suspension. The big grill V8's were the best of the range.

After the Hondas, BMW owned them, then Ford now TATA. I think I would avoid Hondas unless I know the car is perfect and well serviced. I do know anything about the others.

RRV

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#55
In reply to #27

Re: Aluminium Pop Rivets in Steel Car body

04/10/2010 10:34 AM

"I reasonably sure Ford did with their pre-1972 Galaxies as Ford Australia imported them from the U.S. and they came with a Tank SIDO Plate."

I will never forget the time my father, for under $100, bought a several-years-old, but well-running Ford Galaxy in 1975. I had asked him what "rust" meant, so he opened the trunk and lifted me up to look inside. From that vantage point there was far more road than car to be seen. This was in Michigan, so no "SIDO" plate, but whatever materials they did use were very affected by winter road salt.

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#32

Re: Aluminium Pop Rivets in Steel Car body

12/28/2009 9:13 PM

You are creating and environment for Galvanic (dissimilar metal) corrosion. Use steel rivets when attaching the trim clips to your steel panels.

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#33
In reply to #32

Re: Aluminium Pop Rivets in Steel Car body

12/29/2009 12:07 AM

Haven't you read any of these responses? POP rivets have been used for years to hold various plates onto the firewall, inner guards etc.

Would you have a problem with Zincanneal fastened to a steel tube frame ... with pop rivets? That is common on commercial bodies in Queensland (not that that is a great wrap).

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#34
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Re: Aluminium Pop Rivets in Steel Car body

12/29/2009 7:06 AM

I don't think any of the dissenting posters have any idea of the voltage differential between aluminium and steel.They think that dissimilar metals without considering the actual reactions a big no no. You would think somebody has taken the time and trouble to do a little research on this by now without repeating the same old dirge.

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#36
In reply to #34

Re: Aluminium Pop Rivets in Steel Car body

12/29/2009 9:55 PM

Have a look at #35 and you'll see (maybe) that the vehicle's steel is NOT unter threat from pop rivets.

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#40
In reply to #36

Re: Aluminium Pop Rivets in Steel Car body

12/30/2009 8:04 AM

Read all my posts properly and you will see I am recommending aluminium to be ok.

You have misunderstood my previous post

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#43
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Re: Aluminium Pop Rivets in Steel Car body

12/31/2009 2:50 AM

You have my 'umble apologies then.

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#46
In reply to #34

Re: Aluminium Pop Rivets in Steel Car body

01/02/2010 12:43 PM

you wrote: I don't think any of the dissenting posters have any idea of the voltage differential between aluminium and steel.

Handbook of Corrosion Engineering by Pierre R. Roberge

This is the "Bible" for corrosion engineers. Suggest you read it before making general offensive remarks such as the one above...

This book refers to "Anodic index" with gold being "0"

All Al alloys are between 0.75 to 0.95.

Fe (as low carbon steel) is 0.75

Highest index being Beryllium 1.850

Now, based on your newly acquired knowledge, maybe you'll want to change you mind? The prime reason for using "pops" is purely commercial. you just can't beat their cost combination of purchase/installation.

Wangito.

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#47
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Re: Aluminium Pop Rivets in Steel Car body

01/03/2010 6:36 AM

I don't know what you are talking about, maybe I worded that post badly and also you have not read all my posts properly, the dissenters I was talking about are the ones who did not recommend aluminium to be OK.

I said they have not looked at the voltage differentials between aluminium and steel which are not very large as you have seen for yourself:-

Carbon steel =0.85Volts

Aluminium = 0.75 to0.95 Volts

The recommendation for harsh environments is that the difference be no more than 0.15 Volts which puts aluminium in the middle of this reading so either way it is acceptable. Not a perfect match but used correctly will serve for many years.

My knowledge was not newly acquired from you and I suggest if you cannot read the posts fully you should refrain from making smart comments until you do so.

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#48
In reply to #46

Re: Aluminium Pop Rivets in Steel Car body

01/03/2010 7:06 AM

As an aside you wrote in post 22,

#

22
In reply to #20
Re: Aluminium Pop Rivets in Steel Car body 12/27/2009 11:29 PM

electrical connection of Al-Fe is strictly prohibited. You will never find Fe to Al rivets in aviation.

Wangito

I think you will find that copper crimp lugs are used quite often on aluminium cables so long as they are filled with the correct sealing compound to stop the elements creeping in and starting a reaction. As you would know the voltage differential between copper and aluminium is quite high and yet they survive.

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#49
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Re: Aluminium Pop Rivets in Steel Car body

01/03/2010 7:17 AM

Dully noted , Thanks.

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#35

Re: Aluminium Pop Rivets in Steel Car body

12/29/2009 9:54 AM

http://www.engineersedge.com/galvanic_capatability.htm

stainless is not painless; stainless rivets would cause more problems. They don't rust but other things do. From the link above the electro potential between carbon steel and aluminium is about 0.05 to 0.1 Volts, the aluminium will be sacrificed not the steel. Compare this with a potential of 0.3 Volts between carbon steel and stainless steels, here the car body will be sacrificed and will rust.

There are other references I am sure, this was the first I found.

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#39
In reply to #35

Re: Aluminium Pop Rivets in Steel Car body

12/30/2009 7:59 AM

I pointed that out in my post 23 and got no reaction?? also mentioned the voltage differentials you are the first one to appreciate my comments.

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#41
In reply to #39

Re: Aluminium Pop Rivets in Steel Car body

12/30/2009 4:37 PM

Thanks Garth. Aluminium pop rivets it is. I might add that the ID plates on the car are pop riveted with aluminium rivets and they appear to be fine. The previous re-spray person used some kind of white silicon stuff between the clips and body and it was wedged into the rivet hole as if that was the intent. There was no sign of corrosion in any of the 80 odd clip rivets I drilled out. I originally said it was painted 12 years ago but on re-calculation it was about 20 years ago.

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#42
In reply to #41

Re: Aluminium Pop Rivets in Steel Car body

12/30/2009 6:52 PM

Great I am sure your beloved auto will not complain.

The problem is people see a GA and jump on the bandwagon without realy thinking which is a pity as CR4 is supposed to cause people to research the subject.

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#44
In reply to #41

Re: Aluminium Pop Rivets in Steel Car body

01/01/2010 3:55 AM

Might I just add an off topic related topic. I hate pop rivets. i wonder if they were not invented maybe someone else would have invented something better. Firstly they are sometimes the first (and then the last) choice of fastener. If they are too long they make long bananas on the other side, too short they don't work. The riveter sometimes does not fit into the corner or space. The steel wasted part often jams in the gun.Specialized rivets are hard to come by.They are ugly (from both sides). When you make a mistake (like you often do because most pop rivet fixes is quick-fix jobs) you have to drill them out and if you are lucky and the rivet does not spin around you end up with a small aluminum washer stuck on the drill bit.Then also you have to drill the right size hole. If the hole becomes too big because of a couple of re-do's you are stuffed or have to add a washer to the back,thinking why we humans haven't evolved a third arm yet while you hold the gun, press down the material and try to get the washer on. Then the prespex or whatever softer material crack or distorts because of too much pressure. Then the rivet guns... Some small riveters hurt your hand or it is designed for giant grip and you have to yse both hands to get it started.. Big ones are sooooo awquard to work with and air power is not always available to use the nicer tools. I am sure if we do a bit of research before you do a job, you will find a better fastener than a pop rivet for most jobs. Pop rivets should only be used on a quick fix and on big busses. I think we would have been better off using solid rivets. By now someone would have invented a small supersonic hand held vibrating device to set them. As far as the car body thing goes, use them on your cheapy, but dont use them on a restoration job. I think the corrosive effect is a minor concern, they just look ugly but if you don't see then I suppose it is ok.

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#45

Re: Aluminium Pop Rivets in Steel Car body

01/02/2010 8:17 AM

Aircraft manufacturers use a zinc chromate paste for all riveted parts where similar and dissimilar metals are joined, it seems to work well on my own aircraft which is left outside 365/24/7. Its 15 years old and shows no sign of corrosion in any areas where steel is joined to alloy.

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#50
In reply to #45

Re: Aluminium Pop Rivets in Steel Car body

01/10/2010 5:27 PM

Interesting blog.

What are your thoughts of using aluminum flashing instead of steel sheet metal for rust repair. Is this a bad idea?

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#51
In reply to #50

Re: Aluminium Pop Rivets in Steel Car body

01/10/2010 8:37 PM

G'day,

Al Flashing will work but I don't think you want the rivet heads showing. A common trick is to put a bit of bog on the Al and use it as a glue, then spread some bog on the rear side of the "repair" for strength. Maybe use some epoxy filler instead of Polyester. Then fill the visible side of the repair for a good finish. Obviously not a structural repair or a panel that has excess movement.

It's a better repair than cardboard or chicken wire.

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#52
In reply to #51

Re: Aluminium Pop Rivets in Steel Car body

01/11/2010 5:08 AM

You can but aluminium expanded mesh specifically for this job. It allows the filler to penetrate the sheet for a good bond.

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#53
In reply to #52

Re: Aluminium Pop Rivets in Steel Car body

01/11/2010 3:53 PM

G'day,

Good answer but in Australia it is not easy to by in small quantities. If you can buy it as you require it, a good solution. I think something like P mesh is only available in 4'x3' from memory.

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#54
In reply to #53

Re: Aluminium Pop Rivets in Steel Car body

01/12/2010 4:37 AM

In the UK most car accessory shops stock it in small sheets. The brand I know is David's Aluminium Mesh, is it worth asking in your local outlet?

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