Dissimilar Metals
- Thread starter Captain W
- Start date
The rate of corrosion of the anode (aluminum boom) is affected by the comparative areas of the anode and cathode (SS screws). Given the small surface area of the SS screws, no worries about the aluminum.
I would suggest using a waterproof grease to ensure the screws will come out if the need ever arises.
I would suggest using a waterproof grease to ensure the screws will come out if the need ever arises.
It would be my suggestion to use monel fasteners instead of stainless steel.
dj
dj
Monel is one option. At a minimum I’d use an anti-seize compound like Ted-Gel or Lanocote.
Tef-Gel (amazon link) on the threads. Buy a tub, you'll never run out and it is not that much more money than the small tubes.
Lanocote is based on lanolin which comes from raw wool. It is a very traditional lubricate and corrosion protection. Some people swear by it. I find it too sticky which may attract dust and crud.
I have no inside knowledge, however, I suspect that Mare-lube TEF-45 and Ted gel are the same product. Forespar may have bought the company or simply has it rebranded. The formulation seems to be about the same and the fonts on the labels are the same. The company that makes Tef-Gel was small and also made the Ultra Bilge pump sensor.
I have used both Tef-gel and Lanocote. As @dlochner said, Lanocote is pretty sticky, but if you careful with the application and don’t need to remove the screws very often, it is a good choice. I used Lanocote on the 4 SS 1/4” screws tapped into my mast that hold my Mack pack cover at the aft end of my boom.
When i installed the Mack Pack, I also had to drill and tap a few other things in the mast… and I used Tef-gel on those. In the 9 years since I have installed the Mack Pack none of the SS screws have been a problem.
I think Tef-gel is expensive compared to Lanocote, but you don’t really use much for an application.
But my Tef-gel tube dried up and I still have a jar of Lanocote for anything that I was to coat before threading it into an aluminum mast…
I just checked Amazon…
4oz Lanocote =$15
4oz Tef-gel. = $48
You shouldn’t worry too much about using SS fasteners in an aluminum mast or boom, but yes, use some sort of anti-corrosion stuff on the threads and you should be fine.
Greg
When i installed the Mack Pack, I also had to drill and tap a few other things in the mast… and I used Tef-gel on those. In the 9 years since I have installed the Mack Pack none of the SS screws have been a problem.
I think Tef-gel is expensive compared to Lanocote, but you don’t really use much for an application.
But my Tef-gel tube dried up and I still have a jar of Lanocote for anything that I was to coat before threading it into an aluminum mast…
I just checked Amazon…
4oz Lanocote =$15
4oz Tef-gel. = $48
You shouldn’t worry too much about using SS fasteners in an aluminum mast or boom, but yes, use some sort of anti-corrosion stuff on the threads and you should be fine.
Greg
Or even a tiny bit better ...
Locktite LB 8023 Marine. I've tested them side by side, including lots of fasteners in mast test sections left of months hanging under a dock in the inter-tidal zone. Really, they are pretty much interchangeable, but Locktite LB 8023 is many times cheaper, but a small container of any of them will last most of us a lifetime. I use Tefgel more often only because I have a tiny container that fits better in the tool box. Always worth the few seconds it takes.
Lanicote was second to these two, mostly because it was considerably less effective on carbon steel. Locktite is the better choice around the engine.
Locktite LB 8023 Marine. I've tested them side by side, including lots of fasteners in mast test sections left of months hanging under a dock in the inter-tidal zone. Really, they are pretty much interchangeable, but Locktite LB 8023 is many times cheaper, but a small container of any of them will last most of us a lifetime. I use Tefgel more often only because I have a tiny container that fits better in the tool box. Always worth the few seconds it takes.
Lanicote was second to these two, mostly because it was considerably less effective on carbon steel. Locktite is the better choice around the engine.
When I installed a stainless ring on my aluminum mast for my whiskerpole I contacted Selden and asked about this very issue. They include a plastic (?) barrier to place between the stainless ring and the mast, and then recommended liberally applying Tef Gel into the drilled holes, and all over the monel rivets they supplied where they went into the mast. They felt that would massively reduce any dissimilar corrosion.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,809
Me too. One little 3 or 4 ounce tub of Lanocote goes a long way.have a lifetimes supply.
