shim for transom

[hap777]

Would mica board act as a good thin but strong shim between the engine clamps & the fiberglass on the inside of a transom? I only have 1/4" space, but I don't want the clamps to dig into the fibreglass. Thanks

A friend tried to tell me that the transom material (on both the interior & the exterior of the boat where the outboard motor clamps onto it) has to be nothing but treated plywood. I disagree. What do u think?

 

[Old Ironmaker]

Marine plywood not pressure treated if anything. With the small space I would spend a few bucks and use 1/8" Stainless Steel and sandwich it on both sides of the transom or 1/4" on the O/B side. Bolt through and use 3M 5500 and Marine caulking to seal the bolt holes, or use stainless screws on the O/B side if you don't sister the stainless on both sides. It will never rot and is as strong as, well it's as strong as Steel and the clamps will never touch the glass if you do both sides. That's what I would do if it was my boat. Others may have a better method. To save on stainless cut 4 pieces of 1/8" and just place them where the clamps touch inside the transom and outside of it.

 

[Lowlysubaruguy]

Aluminum is cheaper and easier to work with you can cut it with a skill saw file or even router the edges smooth and is plenty strong in this application given that its not really structural . Not to mention Stainless does rust where aluminum will not.

 

[Old Ironmaker]

My pension isn't from an Aluminum company, it's from a Steel Company. Point taken but I would still use stainless.

 

[MTboatguy]

Either one will work, most of us have plywood on our boats, no matter which one you use, just make sure everything is sealed up correctly...