Trojan Boat Forum

I'm looking for the bolt pattern of the shaft strut as my boat is 2 hours away in storage now. I didn't like the look of the plywood block when i was down there this summer. I want to make new backer blocks and change them out. Has anyone ever done this? If so how difficult was it to remove the old backing block? What did you use for the new backing block? Did you make it any larger to help distribute the load side to side?

I just recently removed all the wood backing plates in my F32. The struts, rudders and fresh water valves. Im using 3/4 inch marine ply and they are slightly larger then the fittings and I rounded the corners. Off hand I don't know the dimensions of the bolts. I can measure them later today for you.
Of course you will have to release and drop the bolts then chisel the wood away and then scrape the adhesive off. Then grind and scuff clean the surfaces for the new application.

An option to using wood backing plates is G-10 (fiberglass) panels that can be epoxied to the hull just like wood. They never rot...

WayWeGo wrote: ↑Wed Oct 21, 2020 1:56 pm An option to using wood backing plates is G-10 (fiberglass) panels that can be epoxied to the hull just like wood. They never rot...

I like that idea !!!

I did this. Save your health and your tooling, take it to a granite countertop shop and have them cut your backing plates on a water jet cutter.

Can see my example if you search "tricab underwater exhaust" and "p-dogg".

My second choice would be plywood (exterior is fine -- Google "difference between marine plywood and exterior plywood") soaked in epoxy. It will last as long as you need it to. Consider how long the OEM solution lasted.....

I have used oak to replace backing plates on my struts . G10 looks like a good option too . Marine plywood should work fine . I will have to dissagree on the use of exterior plywood in this application .


On my F36 conv. there are no backing plates for the rudders . FWIW .

P-Dogg wrote: ↑Wed Oct 21, 2020 9:31 pm I did this. Save your health and your tooling, take it to a granite countertop shop and have them cut your backing plates on a water jet cutter.

Can see my example if you search "tricab underwater exhaust" and "p-dogg".

Just to make it easier as the the search engine here is not the best . P-dogg really did some first class work .

viewtopic.php?f=1&t=8020&p=87107&hilit= ... aus#p87107

Thanks Everyone for your input. Sounds like I'm not the first one to want to do it.

Thanks for the trip down memory lane Prowlersfish. I remember when I had time to do that kind of stuff.


And I'm pretty sure that if Trojan couldn't be bothered to seal the limber holes that they cut in my stringers, they didn't spend the extra money to use marine-grade plywood as backing plates......


Https://www.mcilvain.com/news/do-you-re ... e-plywood/

P-Dogg wrote: ↑Fri Oct 23, 2020 8:48 pm Thanks for the trip down memory lane Prowlersfish. I remember when I had time to do that kind of stuff.


And I'm pretty sure that if Trojan couldn't be bothered to seal the limber holes that they cut in my stringers, they didn't spend the extra money to use marine-grade plywood as backing plates......


Https://www.mcilvain.com/news/do-you-re ... e-plywood/

We will have to disagree and thats fine , your link only confirms to me that exterior plywood should not be used in this application . Manly because of voids But then again I would use white oak if using wood . My struts and engine thru hull were not plywood but not factory at least on the engine water intake . I will look at the others next time I am down there .

There are some places exterior would be fine just not my first choice .