BP/W setup - Galvanic corrosion and how to avoid it

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

I used bolts from hardware store and had some gray stuff around the holes after a trip... I'd echo @decompression and say it'll take a very long time to see any real corrosion.
 
Hi divers.

I am in the process of building an aluminium Backplate rig with a primary use of travel diving. I have found an aluminium backplate and single tank adapter, but I'm having trouble finding a compatible bolt to attach the two together that won't cause Galvanic corrosion. Any ideas?

I am planning to buy:

Halcyon harness kit
OMS Aluminium backplate
Xdeep ultralight Single tank adapter

Open to the idea of buying different items to avoid this problem

Take them apart and clean them after each day of diving. It will be long before you notice any built up.

Thinking back, i once owned a oms AL backplate, inwas in a 9 day LOB without taking the STA off, minimal rinsing between dives. I don't remember see any issues. Then of course i took them apart and rinse after the trip. So as long as you are reasonable clean, you should be fine
 
Consider Halcyon's Sta Bolt Retainer: STA Bolt Retainer

1646795082786.png

The black plastic tube isolates the threads from the plate. (It is threaded to capture bolt.)

'Would also use thin nylon washer between plate and stainless washer/nut.

Also, wouldn't hurt to add the small sacrificial Zinc anode Bob DBF referenced. The smallest one I have found is: Zinc 100 Grams Pieces 4n 99.99 Pure

1646796845204.png

If anyone knows of smaller, please post. 'Thinking of attaching to my Hot Dipped Steels.
 
Hi divers.

I am in the process of building an aluminium Backplate rig with a primary use of travel diving. I have found an aluminium backplate and single tank adapter, but I'm having trouble finding a compatible bolt to attach the two together that won't cause Galvanic corrosion. Any ideas?

I am planning to buy:

Halcyon harness kit
OMS Aluminium backplate
Xdeep ultralight Single tank adapter

Open to the idea of buying different items to avoid this problem

I am assuming your talking about the interaction between your ali backplate and STA with the SS connections bolts

I have every kind of combo you can think of, ali backplates, SS backplates, ali STA, SS STA, ali rebreather cans to ali backplate or SS backplates, twin set SS band bolts to ail backplates, etc. and I just connect them and go diving. In all my years of salt water diving never had an issue.

I think you are over thinking the issue, yes it theory your correct it does happen but it is so minimal it's not actually an issue . If it was a major problem then you would see lots of industry solutions in place. However every backplate, twinset, and rebreather that I know if is connected with SS hardware with the exception of the odd ball overachiever that feels the need to use $30 titanium bolts.
 
https://www.shearwater.com/products/swift/

Back
Top Bottom