DF Vortex 34 Hydro Build

[rol243]

As mentioned i had a few fins to test on the gas hydro and some of the fins made the boat very very sensitive just in the straights , it was like the boat just wanted to wonder off course on its own and when radio input was given for correction only the slightest amount of rudder control was used. the hull was almost un driveable until i ended up buying a Titanium cnc fin as used on most Whiplash sport hydros., was a dream to drive then. so play with the turn fins until you find the right one and i am sure your hull will go really well. make sure c.o.g. is correct too.

[CraigP]

I’m going to just swap over to my bent fin... getting ready to run it now. CG is correct, thanks for the input! Wish me luck!

[rol243]

OK let us know results.

[CraigP]

Just got back, like a new boat! Very high winds, average 7-10mph, gusting 15-28. I almost decided it was too much. But felt that it would be a perfect time to check out adverse conditions. Man, I wish I had that GoPro! There wasn’t white caps, but consistent 2-4” rollers. Boat handled it great! The bent fin is definitely better than curved. Dropping the strut 0.100” and making sure it’s at zero degrees just took all the porpoising out. The boat hit rollers 3-4 times, each time coming completely out of the water, but staying absolutely parallel to the water. It just settled right back in. It even jumped in the corner and flew the same way. No doubt CG is right. The bent fin also is about 5/8” further back than the curved fin, just because of mounting hole differences. Right sponson ran more free and only noted sponson walking while going over some pretty high rollers. I checked CG before running at it was right on the leading edge of the turn fin. When I got back, I noted strut, rudder and turn fin setup in my notebook. I also ran a M445, has been my best prop. I had a small, 42X55 2-blade Grim Racer with about 17 degrees of rake on it yesterday. This boat just doesn’t like high rake props. One other note, it was so rough, the ESC Mount broke loose! Didn’t cause an issue, but certainly a testament to rough water. Thanks Ronald for some excellent pointers!

[CraigP]

Here’s a pic of my brother’s GP boat in San Diego. It’s wave jumping too... My boat looked like that, but much higher out of the water. I love seeing hydros fly!

[CraigP]

For you hydro lovers, here’s a pic of arguably the most dominant Unlimited in history, the Bardahl Green Dragon! This is what my little hydro looked like, rudder completely out, flying parallel to the water. I’m a happy guy tonight!

[rol243]

certainly a great old hydro there [ miss bardahl ] used to be avaialble in kit form and maybe you can still get them other than planes only. hope your strut isn,t set at that same angle in pic Craig. lol

[WestJL21]

Dilly, Dilly CraigP !

[CraigP]

certainly a great old hydro there [ miss bardahl ] used to be avaialble in kit form and maybe you can still get them other than planes only. hope your strut isn,t set at that same angle in pic Craig. lol

You know they tried for years to come up with a universal joint that could take the shaft HP, never did it. The shaft angle has always been a design flaw that begets many different work arounds. We are lucky to set it neutral!

I’ve thought about building the ‘66 Bardahl Ron Jones cab-over, that killed Ronny Munson on that fateful day in DC. I was there... But shovel noses are a real design compromise. If I did build one, it would probably be my Dad’s Parco O-Ring Miss, the Karelsen hull..

[CraigP]

Dilly, Dilly CraigP !

Not sure what this means, I must have gotten off the bus!

[Beaux]

Hey Craig, Beaux here do you have any pictures of your strut and rudder set up. I just ordered mine and was curious . Thanks.

[CraigP]

Here’s a couple of shots. This is all Speedmaster hardware. It’s the larger hardware with the rudder cut down. I used the larger strut to have enough meat to put in a rear lip seal, to stop grease loss and prevent water from breaking down the grease.

[rol243]

where the shaft tube log joins up with the strut, use some heat shrink tube , this will keep water out and not create any drag as you have now CraigP.

[CraigP]

Yes, it’s an old pic, someone posted that recommendation a while ago and it’s had heat shrink with silicone underneath since August. The stuffing tube has too small a bend radius and was replaced in the summer. That was another good piece of advice I received. I’ve learned much here!

[srislash]

What are all the holes in the strut upright Craig?