Copper slip and alternatives

[NickGM]

For a number of years I've been using copper slip (or copper grease) on just about anything with a thread on my bike. I recently heard that it's actually a bad idea to use copper slip with two different metals, particularly alu and steel as it causes corrosion. Something about the copper becoming an anode (can't remember chem too well). Then there are other people who say that this is exactly how copper slip protects the two metals, by being a sacrificial anode. Then there are other people that say that the grease around the copper flakes (in copper slip) prevent it from ever reacting with either metal so one should worry either way. 

 

I've actually yet to have a problem with this - I've never noticed corrosion on any of my previous bikes which were all alu. But I've also never owned a steel-framed bike (until now) and don't want to take any chances.

 

Does anybody have any recommendations/experience with this? Also, what is your go-to thread grease?

Edited August 28, 2020 by NickGM

[Barry]

Snip: Copper grease is an anti seize compound designed to operate at extremes of temperature. Note, it is not a lubricant. It is often used to help prevent seizing and corrosion at high temperatures in the automotive industry. Copper grease is effective within the temperature range of of - 40° to + 1,150° celsius making it an ideal choice for use on wheel nuts & bolts, flanges, studs and exhaust brackets to prevent seizing.

 

 

 

WHAT IS COPPER GREASE?

Copper grease is a specially formulated anti-seize compound manufactured by combining fine copper particles and high grade corrosion and oxidation inhibitors. The grease is created through a procedure that combines oil with soap. This imparts a sticky quality to the grease which enables it to cling to the surface it has been applied to and stay in place longer. Copper grease is an anti-seize grease as opposed to a lubricant.

[WrightJnr]

I see thread. I put Copper a Slip. Don’t care the material. It’s never let me down.

[Butterbean]

Copper slip for pedal threads. Waterproof grease for pretty much everything else. Brake disk bolts and sometimes pivots have locktite. Grease down the Seatpost and for BB and headset. I'm far from a great mech tho.

[Barry]

Copper slip should be good for all the nuts and bolts even the seat post but Loctite for those that require Loctite

[TNT1]

I see thread. I put Copper a Slip. Don’t care the material. It’s never let me down.

I also use it on seat pins and stems and handlebars.

[TNT1]

Copper slip should be good for all the nuts and bolts even the seat post but Loctite for those that require Loctite

Nothing on a bicycle should ever require loctite.

[Barry]

Nothing on a bicycle should ever require loctite.

Yes i agree with you but also same time disagree maybe this can be explaind in more detail

The tec courses say use it and manufacturers use ir on parts so yes i am alwase in two minds

[RaymondC]

Nothing on a bicycle should ever require loctite.

The lock ring on the Hollowgram crank spider needs 1 drop, no more noise.  

[Popit]

Nothing on a bicycle should ever require loctite.

Lots of bolts come from the bike factory with BLUE loctite . Handlebar stem bolts , brake disc bolts , rotor bolts , but all manufacturers still give recommended torque settings as well . 

[Lance Stephenson]

Nickel Compound for dissimilar metals.  Copper Compound for same metals/although in application specific. (big threads with low pressure (under 20nm in my experience is good). smaller threads with higher pressure (over 40nm then a teflon grease is better) . tiny threads like stem bolts, a drop of wet oil is great.

[WIPEOUT 1000]

Lots of bolts come from the bike factory with BLUE loctite . Handlebar stem bolts , brake disc bolts , rotor bolts , but all manufacturers still give recommended torque settings as well . 

From an engineering perspective, especially to protect against galvanic corrosion, basically every thread on a bike should be treated with either an anti seize compound or a thread locker. What you use depends on what the thread is for and what the material is. E.g. stems bolts definitely need a thread locker, but pedals that self tighten during normal pedaling require an anti seize compound.

[Bateleur1]

Nothing on a bicycle should ever require loctite.

 

Would tend to agree with you but had an issue with a bolt on my saddle that kept "relaxing" every so often which caused minute slip movement on the saddle and after a three hour ride the saddle would typically slip back 2-3 cm.  Even though tightened to the prescribed torque.  I eventually put a drop of loctite and bobs your uncle ... sorted.

[Gerhard765]

For a number of years I've been using copper slip (or copper grease) on just about anything with a thread on my bike. I recently heard that it's actually a bad idea to use copper slip with two different metals, particularly alu and steel as it causes corrosion. Something about the copper becoming an anode (can't remember chem too well). Then there are other people who say that this is exactly how copper slip protects the two metals, by being a sacrificial anode. Then there are other people that say that the grease around the copper flakes (in copper slip) prevent it from ever reacting with either metal so one should worry either way. 

 

I've actually yet to have a problem with this - I've never noticed corrosion on any of my previous bikes which were all alu. But I've also never owned a steel-framed bike (until now) and don't want to take any chances.

 

Does anybody have any recommendations/experience with this? Also, what is your go-to thread grease?

Hi Nick. the form of corrosion you are referring to is galvanic corrosion (where two different materials are in a electrolyte). The difference between the electro-negativity of materials need to be large enough before galvanic corrosion will start. Copper and aluminum alloys are a bit different. Ally sits at -1 to -0.75 and copper at -0.3. With copper being higher it will actually be the aluminum which will corrode away. So I don't agree with sacrificial anode statement as most parts on bicycles are aluminum (for my budget). This could be true (could as I assume that copper slip behaves the same as copper) when you have un-coated aluminium in contact with the copper slip. In most cases the ally parts are anodized and painted. A good paint layer prevents galvanic corrosion.

 

I still use copper slip on my bike and will continue to use it. If there are problems you might see it on areas where the paint was damaged before mating the two parts. The aluminium will corrode away where it was in direct contact with the copper slip. How fast this can happen is difficult to predict but what I can say is that if copper slip was such a big problem it would have received much more attention in the forums.

 

Have a scroll trhoug this link:

https://www.corrosionpedia.com/an-introduction-to-the-galvanic-series-galvanic-compatibility-and-corrosion/2/1403

There is table showing the galvanic series of the different materials we normally refer to.

 

 

Good luck and happy cycling

[Jehosefat]

I use the Park Tool Anti-Seize Compound instead of Copper Slip. Never had any issues.

 

https://www.evobikes.co.za/park-tool-anti-seize-compound.html

^ it's out of stock there but I put the link in for reference anyway

[ChrisF]

Nothing on a bicycle should ever require loctite.

Nice upgrade to Sram derailures though ...

 

 

I also put a drop of blue locktight on the bolts for the brake calipers ....