Mixed metals in an aluminum boat arent a good combo, what that uni-strut made of?
Neither is what appears to be pressure treated lumber & plywood.
None of that goes well in a wet environment w an aluminum boat.
I can answer some of this.
The uni-strut is steel. And being very familiar with it,.
He has 2 types installed....
I can see some is true gray Galvanized,. usually for exterior/outside...
Wonder if the cut ends were re-coated with anything,. or the rust will start in days.
Next I can see the zinc/plated/anodized, thin shinny uni-strut, that is typically installed indoors or limited element exposure for best results, again wonder if ends had any protection applied.
I always cut, filed, smoothed and cold galved cut ends(just me)
Steel would have been my absolute last choice, especially against aluminum, painted, coated, or not for either or both. but oh well.
The uni-strut will do a fine job supporting the floor, plenty strong,. until the dissimilar metals start arguing, and holes show up in aluminum in a few months or a year.. let alone the rust that will eventually start and Bleed/drip, condensate and stain aluminum below unless he pour foams it. think he mentioned sheet foam already.
I think he needs pour foam for support of the hull. or add some stringers(un-engineered)And not pressure treated...
You added probably 50-100 pounds in uni-strut. I count at least 7 pieces. it adds up...
That's again steel, not wood or aluminum.
I think I get and understand what he's doing, it's a budget build with whatever he has laying around or can get his hands on easily. and just get a end result.. functional back yard build or what we would do on-site in a "building" atmosphere.
Looks like he's making do with what he has. (and I get that)
And it will get him through a season or 2 and then it's going to be in really bad shape again. as in aluminum hull damage, corrosion, pits, then Holes,. in that order.. Unless he takes some special precautions, and keeps an eye on things.. closely.,
IMO.
In his defense, If he can get a barrier between the strut and aluminum that "may" get by with only a weight strike. Polyester/roofing caulk something other than silicone. SEPARATE the dissimilars. Cushion it well.
Get the cut ends smoothed covered. so sharp burs aren't gouging into the aluminum, And cushion it, even put some rubber between it, Keep it from rusting and Rubbing, (think busting waves and beating on trailer going down the road, pot holes, RR tracks, rough bridges etc.)
The zinc strut will last several years if it's halfway protected. But its the Heaviest non rotting material he could have picked..
**The pressure treated against aluminum needs to come out Yesterday if not sooner, It will end up cutting the hull like a buzz saw.**
The pressure treated against aluminum alarms me way more than the steel to aluminum and thats still bad but... He only has a few contact points and they can be addressed and cleaned up "to make do" in a worst case.(uni-strut I mean)
Not to beat him up, I understand not having piles of money to throw at a boat.
But if you do non-standard things that can lead to severe problems, take a little extra care to ensure a little better end result at the cost of saving money.
Remember at some point this could become unsafe for you and Worse, others.
So respectfully, take a little added care and do the best you can with what you have.
Best regards on the build.
