AndyGT
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| posted on 29/12/13 at 11:23 PM |
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copper slip
just about to change some glowplugs on a 2001 zafira 2.0 dti and wonfered if it would be a good idea, or not, to put copper slip on the threads for
easier removal on next service?
would there be any weird chemical reactions between steel, copper and alloy?
thx in advance
andy
nothing is impossible
everything is possible
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NigeEss
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| posted on 30/12/13 at 12:09 AM |
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Should be fine.
Time is an illusion. Lunchtime doubly so.................Douglas Adams.
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britishtrident
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| posted on 30/12/13 at 07:11 AM |
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Copaslip causes more problems than it prevents, the most effective compound is aluminium-graphite paste as this prevents galvanic corrosion. It is
also very efective at preventing alloy wheels siezing to the hub and is specified by Land rover for that purpose.
I use Delta D515 but you will find other brands on eBay if you search on "anti-seize compounds".
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
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snakebelly
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| posted on 30/12/13 at 08:18 AM |
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"Copaslip causes more problems than it prevents"
Sorry cant agree with that, been using it for donkeys with no issues, I'm not saying there aren't now more advanced or even better anti
seize compounds but to say it causes more problems than it prevents is just nonsense!
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cliftyhanger
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| posted on 30/12/13 at 08:30 AM |
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I too have been using copperslip. Built a triumph, ran it for 15 years and when I took it apart nothing was seized. Good enough test for me. (Every
other such car has many many seized bolts, even after a few years)
I guess there may be better, but find it difficult to fault copperslip.
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AndyGT
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| posted on 30/12/13 at 08:46 AM |
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thx chaps!
i am going to presume that for low heat and general use copperslip is difficult to beat and for high heat applications it is better to use the
alluminium graphite compounds.
Happy motoring for 2014 and above all be safe!
nothing is impossible
everything is possible
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britishtrident
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| posted on 30/12/13 at 09:06 AM |
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I first used Coppalip 40 years which is more experience than both of you aded together it is better than nothing but not much better. If you examine
the threads of Lambda sensor you will see they are only ever protected by graphite based compound and even after years of service in a highly
aggressive environment they usually still unscrewed using the corect tool without difficulty.
Where you have an aluminium to ferrous metal joint adding copper to the mixture of metal will only make maters worse.
A decade back Rover and LandRover dealers were having major problems with alloy corroding on to the whel hubs, the dealers found Coppaslip was only
just increasing then problem. Landrover instructed their dealers to use aluminium-graphite compound and started using it in production and the
problem disappeared.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
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snakebelly
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| posted on 30/12/13 at 02:44 PM |
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"I first used Coppalip 40 years which is more experience than both of you aded together"
What a load of cobblers, you don't know both of our ages and im guessing that you and me aren't to far apart so unless the other party is
about 10 then your wrong, then again your reputation precedes you so thinking about it you cant be wrong in any circumstance.
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Dopdog
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| posted on 30/12/13 at 05:42 PM |
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Popcorn anyone 0
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sdh2903
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| posted on 30/12/13 at 06:03 PM |
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Think BT is masquerading as the grinch, he gets more arsey around this time of year
Salted popcorn for me please!
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COREdevelopments
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| posted on 30/12/13 at 07:31 PM |
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Copper grease has a number of uses. However if put between alloy and steel. e.g. A wheel and hub and introduce salt water it will cause galvanic
corrosion. I too have been using it for years. I still use it and will keep using it, but only on certain jobs.
It does cause problems with alloy wheels and have had many problems with removing wheels which have been coppergreased. Hope this helps.
Rob
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black fingernail
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| posted on 30/12/13 at 08:13 PM |
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Got to agree with BT, I only use copperslip on certain jobs, but only to use the tin up, it is old hat now and needs to go the way of betamax etc
there are much better anti seize compounds available now.
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Dopdog
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| posted on 30/12/13 at 09:41 PM |
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I found this would love to say it is mine 
Galvanic Corrosion
The manufacturer uses a number of different metal alloys, plastics, and coatings - each selected for its cost, weight, strength, appearance, and
corrosion resistance among other things. What also needed to be considered, is that when any two different metals touch each other, electricity flows
between them (which is how a battery works), and the surface of the metal lower on the list corrodes.
For example, when aluminum or magnesium are in contact with carbon or stainless steel, this galvanic action will corrode the aluminum or magnesium. So
the approach is to use steel fasteners to fasten steel parts together, whenever possible.
One problem is that aluminum fasteners aren’t very strong, so aluminum parts are held with steel fasteners, but in special ways to reduce corrosion.
Carbon steel bolts threaded directly into aluminum is generally avoided for example.
Here’s a list of some commonly-used metals. The farther apart (top to bottom) on the list the two materials are, the more corrosion that will occur to
the material lower on the list when they are held in contact.
Gold
Graphite
Silver
18-8-3 Stainless steel, type 316 (passive) 18-8 Stainless steel, type 304 (passive)
Titanium
Nickel (passive)
Silver solder
Bronze
Copper
Brass
Nickel (active)
Tin
Lead
18-8-3 Stainless steel, type 316 (active) 18-8 Stainless steel, type 304 (active)
Cast iron
Mild steel
Aluminum 2024
Cadmium
Galvanized steel
Zinc (commonly used as a sacrificial anode in marine environments) Magnesium alloys
One way to control this galvanic corrosion is to use metals closer to each other in the above list, or by electrically-isolating metals from each
other. Cadmium plating of steel fasteners for example, is used to reduce the metal dissimilarities with aluminum and magnesium. Paint and coatings are
used to prevent metals from touching.
Anti-Seize Products
If a fastener won’t get disassembled for long periods of time, it’s a candidate for using an anti-seize compound during assembly. There are three
formulations widely-available based on copper, aluminum or nickel.
The way anti-seize compounds work is by placing a third dissimilar metal between the two base metals. So the corrosion of a thread in a magnesium part
caused by a titanium bolt is reduced by an intermediate copper-rich or nickel-rich thread coating. The aluminum anti-seize compound is for use between
(say) stainless steel and magnesium.
Torque Values
If the same materials are being fastened together, then they are assembled dry to the manufacturer’s torque values - unless otherwise specified. In
critical fasteners such as the axle nut that holds the rear wheel on superbikes, the spec calls for lubricating the threads prior to assembly. The
torque spec assumes a lubricated thread. Read your manual.
In general, a thread treated with either an anti-seize or a lubricant requires a lower torque value (than a higher-friction dry thread) to create the
same tension in the fastener. So, if you make a modification that changes a component material, such that anti-seize is now needed, you’ll need to
torque the fastener to a approximately 10% lower value to avoid over-tensioning the fastener (according to Machinery's Handbook, 25th ed.). A
new torque wrench is usually accurate to ± 3%.
Vibration
If a bolt is torqued to the specified value there’s no need for thread locking adhesives. When the manufacturer is designing a critical connection
that will be subjected to vibration a lock washer is incorporated to prevent loosening.
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