Mounting Turn Fin ideas

[JimClark]

Ok my current build where the turn fin mounts is a double thickness of light ply. I have no way to get into the inside to thru bilt the mounting screws so right now all I could do would be to use wood screws and I think the wood it too soft for that. I am thinking of taking the sponson riding surface off (about 1/2 of it ) so I can add a piece of aluminum to tap for the turn fin mount. Just looking for other ideas so I might not have to pull the sponsons apart any suggestions?

Jim

[detox]

I would mount bracket with slightly long course thread wood screws . Then drill small hole beside mounting surface. Then using syringe inject strong thick epoxy into backside void. Is there a void behind double ply inside sponson? Some epoxies are very strong (thick Liquid Weld maybe) Coat your screws with thin grease so epoxy will not bond.

Another option is to use long stainless wood screws (Ace Hardware has 2"-3"). This would thread into foam also. Predrill wood with small diameter bit (do not predrill foam inside)and do not overtighten screws. This option should work. If not then I would cut hole in sponson as last resort.

Nice build BTW.

[JimClark]

Think I am going to just take the bottom of the sponson off so I can get inside and do the job the way I would like it very strong.

Jim

[lenny]

I need to do something like that on my clone hydro to,
And the rudder mount to.
I see your turn fin is flat, Is it better to use flat turn fin, Than curved ?
The one on my clone is curved and its hopping in the turns pretty bad.
I do not know what to do about that.

[Boaterguy]

the curved fin (curving under the boat) helps with the hopping, I had a sheet metal turn fin on my hydro and I found bending it more kept it down better in the turns, but slightly hindered the straights.