hydrofoils

[starcrafttom]

that sound great. i will research the dimensions and get back to you. the filing and fitting I can do myself. Its that whole bending in a straight line that I don't have the equipment for. I will pm you in a few days.

[Norm S]

Anybody out there that can help me out with dimensions for a permatrim? I'd like to try and build my own for my new 60. I figure I can make a swag between the sizes of the 70-90s and the 40-50s. Also thickness of the aluminum would help before I go scrounging for material. Thanks in advance.
Norm

[oldgrowth]

Norm;

I made a hydrofoil for my 16’ Cruiser. I have a 50 HP Honda on it and the hydrofoil works very very good. Does not mater how heavy I am in the stern or light in the bow, I am able to lever the boat with the engine trim.

The hydrofoil is a close copy of the Permatrim. I did not have an actual Permatrim to copy, so I guessed at the dimensions. I am pretty sure mine is a thinner gage aluminum that the Permatrim, so I put a slight break (just a few degrees) in the middle for strength. The thinner gage aluminum will create less drag. I actually increased my top end by 2 MPH with it. There has been no adverse affects to my boat with it.

The thumbnail photo below will take you to the drawing in my photo album (last photo on the page). Actual photos of it on my engine are in my Boat Projects Album, photo numbers 23 & 24 (last two photos on previous album page).

You may have to make yours slightly larger. If you do, I would not make it more than 20 inches wide (16” with bends) and 17.3 inches long. That will give you an overall 17% increase in size. Your engine has 20% more power and your boat is around 15% larger than the 16, so the 17% increase should be about right. The cut out to mount on your engine may be different also.

[Byrdman]

Norm.... hummm... new motor, more speed, new fin.... even more speed.... Ever watched one of those blow over backwards boats on ESPN?

[Falco]

Question: With standard trim tabs, it's vital that they be retracted (full up) when motoring in following seas to prevent one or the other being "caught" and rapidly spinning the boat broadside to the waves. (I learned the hard way.) Has anyone had experience running with permatrims or permatrim-like attachments in following seas? What about on twins (which would be more like a trim tab set up)? Any problems?

Thanks in advance.

[Papillon]

I got my new hydrofoil installed yesterday and took it for a short spin with Jim (Duck) and another friend aboard. Since I was replacing an old plastic (rubber) doe fin, I did not see a dramatic difference in "hole shot" but where I did see and feel the difference was in steering response at slow speed (docking). I have Bennet Trim tabs as well and wishing for this feature more then anything else.

For 39.95 plus shipping I am more then pleased with the setup.



Additional photo in my album.

[james]

I just got my bobs hydro installed last night...
I will see this weekend what differance it makes.
Glad to see you like your's.

Also when I installed mine i ended up with about a 1/8 gap in the front between the stabillzer and the hydro...I don't think it will be a problem, but I am not totally happy with that.
May take it back off and grind a few places to get a flush fit...we'll
see. ended up using 5200 on it since my 4200 was old and would not flow. I wanted to get it installed. Might be crucial error on my part if I need to take it off.. .

James

[Papillon]

I had a problem with the motors trim tab, and had to cut out the notch because of the angle of the tab. I called Bob's and this was what I was told to do. I had the same problem pertaining to bedding compound, and I subsituted Liquid Nails, since it is just to provide for reduced vibration and not required to really hold anything together.

Good Luck and let us hear from you once you have tested it out on the water.