Re-enforcement tunnel for RMK PRO 2011-2012

[Effika]

The relative area of the anode and cathode has a pronounced effect upon the amount of corrosion that occurs due to Galvanic Corrosion. A small anode (the less noble metal, such as aluminium) joined to a large cathode (the more noble metal, such as stainless steel) will result in a high current density on the aluminium, and hence a high rate of corrosion.
The corrosion is concentrated by the area difference. Conversely if the area of the anode is large compared to that of the cathode this dilutes the corrosive effect, in most cases to the extent that no problem occurs. It is common practice to use stainless steel fasteners to fix aluminium sheeting or signs, but if aluminium screws were used to fix stainless steel the screws may rapidly corrode.
An apparent contradiction of the area effect on Galvanic Corrosion occurs when the component comprised of the two metals is only partly wetted. Consider for instance a stainless steel bolt in an aluminium plate; if water collects in the corner at the edge of the bolt but the remainder of the plate remains dry, the effective area of the less noble aluminium is only the wetted region, which may be only a similar size to that section of the bolt that is wetted .... thus it is quite possible for the aluminium plate to be galvanically attacked in the region immediately surrounding the bolt. Only the wet “area” counts.

There is our case:

Conversely if the area of the anode is large compared to that of the cathode this dilutes the corrosive effect, in most cases to the extent that no problem occurs.

 

[Butta]

So I would also use Stainless Steel rivets then.....aluminum rivets would present a prime galvanic corrosion setup with a large cathode (the stainless plate) and small anode (the aluminum rivets).

Also, I would pay particular attention to the relative wet areas:

"An apparent contradiction of the area effect on Galvanic Corrosion occurs when the component comprised of the two metals is only partly wetted. Consider for instance a stainless steel bolt in an aluminium plate; if water collects in the corner at the edge of the bolt but the remainder of the plate remains dry, the effective area of the less noble aluminium is only the wetted region, which may be only a similar size to that section of the bolt that is wetted .... thus it is quite possible for the aluminium plate to be galvanically attacked in the region immediately surrounding the bolt. Only the wet “area” counts."

Still, I see this setting up for a rapidly corrosive environment. Something everyone who installs this should keep an eye on. Nothing worse than installing an upgrade that ends up detrimental to your original product (the tunnel).

 

[HOOCH256]

If you were really concerned about it either powder coat it (is what id do) or take some clear urethane and spray the back of the plate before putting on the tunnel! My 2cents, cause I can tell you from my days in metallurgy studies that galvanic corrosion is very fast and very destructive! It is the fastest form of corrosion around!


---
I am here: http://maps.google.com/maps?ll=48.148994,-103.579650

 

[Effika]

Huuumm, i m thinking to create a thin film of polymer or some think like that whit the same shape of my ss parts to insert between it.

what you think of it?

 

[AkLogan]

Get them powder coated. Should be cheaper and easier. And will have more of a bling effect

 

[robertyoke]

im guessing that alot of the rivets in the tunnel are ss, and the bolts are too or just zinc plate. I know alot of the fastners and the reinforcing plates were just plated steel on my yamaha tunnel.

 

[HOOCH256]

3M makes a great product that you put on the front of your car and it's called ClearShield the stuff is practically bullet proof, sticky as hell and super thin!


---
I am here: http://maps.google.com/maps?ll=48.162214,-103.644652

 

[sledrush]

Or build some aluminum ones that act as rail stiffeners too... I better patent that. lol

 

[Effika]

im guessing that alot of the rivets in the tunnel are ss

Effectively, there are high quality ss rivet.

After a discussion with specialists, they say to me that it is improbable to meet right condition to create a damageable galvanic corrosion with this parts on a snowmobile.

It is true that you should not neglect this detail in mechanical conception, but in what concerns us, we do not have to worry about it

 

[allied1]

Just installed these on my Pro's. The fit was perfect. Got the kinks out of the tunnel and riveted these on and we are good to go. Straight and stong. Thanks Effika!

 

[Effika]

I woudl like to see it on your sled Mike if is possible!

Thanks!

 

[allied1]

Here ya go. This tunnel was bulged out pretty bad on both sides and starting to crack. This kit pulled everything nice and straight. Good fix and very straight forward.

The Fix: Several hours and a couple hundred bucks.
The Damage: 4th of July in Cooke, priceless!

 

[Effika]

Ho, Yha! Good work !