Re: [electricboats] Motor Mount and Thrust Plate design - hoping for feedback

Steven,

   All my stuff is directly exposed to salt spray. I've had several sailboats over the last 30 years and never seen anything like the conditions at my house. I had a powder coated mild steel mount for a small solar panel on the roof. A year later I found the panel laying on the roof and a small nail sized sliver of what was left of the mount. So very extreme conditions. Enclosed in your boat 304 will probably be fine. Even steel if you brush coat it as thick as you can with cold galv paint. I would not use aluminum bolts. Use SS and galvanically isolate from dissimilar metals with silicone caulk or plastic inserts. I've never tried it but I bet anti seize would work for a SS bolt into an aluminum threaded hole. One thing I use out here for my Lifep04 batteries (aluminum cases) is a compartment floor lined with thin plastic cutting board from Amazon. Also between cells. Cuts easy with metal shears. Another thing I've noticed is the foreign SS is more hit or miss than the domestic stuff. More corrosion and spalling of bolts/nuts. But most of it is fine.

Jerry Barth

Sent from my Sprint Tablet.

-------- Original message --------

From: Steven Borg <steve@theborg.family>

Date: 12/30/21 6:56 PM (GMT-04:00)

To: electricboats@groups.io

Subject: Re: [electricboats] Motor Mount and Thrust Plate design - hoping for feedback

Thanks, Shredderf16! I looked at onlinemetals.com, and they have 316 in stock as well as 304.  The price is only about 30% more for 316, so likely a good choice.  I also reached out to oshcut.com. They don't have it and aren't willing to cut metal bought elsewhere. BUT onlinemetals.com does laser cutting through SendCutSend, so I'll look into seeing if I can get the best of both worlds!

Failure of 304 in 3 months is pretty rough!  In my use, I won't get any salt water on the metal, and the iron and steel on the motor and surrounding areas went 30 years without rusting (although initially protected by paint). So I'm not going to feel too badly if I have to stick with 304, but I will certainly prefer 316 if I can swing it!  Thanks for your recommendation and experience.

As an aside, and coming back to price...  Comparing oshcut and onlinemetals/sendcutsend, it looks like oshcut (after shipping) is about 40% less expensive.  ($800 vs $1300)