any issues bolting galvanised steel bracket to checker aluminum

[cancan]

I have a checker plate toolbox and want to bolt 2 L brackets to the lid. I have found the size I want but in Galvanised steel. Is there any long term issues with the 2 metals or should I have a rubber strip between the 2 or find aluminum L brackets instead.

[darren]

Its no good on somthing like a boat but wouldnt worry bout a box at all

[sparksy]

No problems there. The sacrifician anodes  made from zinc are fitted to aluminium hulls and outboards to stop the ali from corroding in salt water, zinc ( most brackets are zinc plated ) is very compatible with aluminium. On the other hand stainless steel hates aluminium and will react sometimes quite radically. Alloy trays and the alloy frames are bolted together with zinc plated bolts and not stainless bolts for that reason.

Wayne

[V8100]

Gal will be fine but put a small amount of silicone in between

No problems there. The sacrifician anodes  made from zinc are fitted to aluminium hulls and outboards to stop the ali from corroding in salt water, zinc ( most brackets are zinc plated ) is very compatible with aluminium. On the other hand stainless steel hates aluminium and will react sometimes quite radically. Alloy trays and the alloy frames are bolted together with zinc plated bolts and not stainless bolts for that reason.

Wayne

Sorry sparksy but stainless and ally work very well together. There is very little if any reaction between them at all.
eddy

[Humbolt]

Yeah sorry but i have to agree with Sparksy, there will be a reaction between alloy and stainless steel. i have seen this many times!!!
It reminds me of when people say stainless doesn't rust, it does given the right circumstance! 

[sparksy]

I worked for years installing solar installations with the lighthouse service and a continual problem was the stainless fitting reacting with the aluminium frames of the panels. To such a extent that the stainless bolts "ate" through the aluminium frames.

If the surface area of the aluminium is greater than the stainless as in the case of using stainless bolts or screws then galvanic corrosion will occur on the aluminium. this is made worse if the surfaces are exposed to the weather.
I now work in the food industry and the same problem exists with stainless bolts etc holding aluminium fixtures.

Just try and remove the bolts holding a outboard motor  together.
Zinc and aluminium are close on a galvanic chart and therefore will show little effect.

[RebsWA]

Interesting... I have a 10 year old plate ally boat and all the fittings are mounted with stainless bolts, nuts, screws or self tappers and I never noticed any fretting between the two metals.

[Kameron]

I worked for years installing solar installations with the lighthouse service and a continual problem was the stainless fitting reacting with the aluminium frames of the panels.

Slight hijack sorry:
Did you ever come across a character called Charlie Ferguson?
My family use to have a boat out of Broome (early 90's) that ran service guys to lighthouses up in the kimberleys/rowley shoals etc.

Stainless steel and aluminium don't like each other.  Use a product called Duralac to put between the dissimilar metals, on threads etc. It will stop the galvanic corrosion.

[D4D]

x2 for Duralac, use it on my tinnie

[sandman]

In case anyone is interested, I have attached a copy of the Galvanic chart for future reference. Basically the further apart two metals are the more likely there will be a reaction between the metals

[LJs GU]

Thanks Sandman, that helps me a lot.  Any chance (if you know how) of linking it to a bigger pic?
Also do you know what the red blocks for the stainless indicate (compared tot he blue blocks)?

LJ

[OffRoadDave]

Cheers for the chart sandman but I'll second LJs ask for a higher resolution image.

Check out the link below, it has a decent size chart and an easy to understand explanation of why the metals react to each other.

http://www.westcoastanodes.co.uk/Boat_Anodes/ANODES_AND_GALVANIC_CORROSION.html

[sparksy]

Slight hijack sorry:
Did you ever come across a character called Charlie Ferguson?
My family use to have a boat out of Broome (early 90's) that ran service guys to lighthouses up in the kimberleys/rowley shoals etc

Hi Kameron
PM sent