DF Vortex is in. YAY. Dumb question though

[Blackjack-sven]

I just got the DF Vortex in from O.S.E. and it looks great, BUT......the hatch seems to be very warped. How can I un-warp this?

[Jesse J]

Are you sure it is a warpedness that won't go away with hatch tape?

[Rumdog]

you cant. i tried a million times. it is magical though! once you get it in the sun, or moderately warm it will instantly fix itself!!! mine was badly warped and i tried re-glassing its underside. didn't work. once it cools it will reset as warped though. try heating it with a hair dryer and bending it how you want the hold it in place while it cools.

[Blackjack-sven]

you cant. i tried a million times. it is magical though! once you get it in the sun, or moderately warm it will instantly fix itself!!! mine was badly warped and i tried re-glassing its underside. didn't work. once it cools it will reset as warped though. try heating it with a hair dryer and bending it how you want the hold it in place while it cools.

Ok, sounds like a plan. Few more questions as well.

1. Where should the CG be roughly?
2. How deep should the prop be? And where should it exit?
3. How heavy should it be once completed?
4. Where should all the equipment be placed roughly?

Pics would be great.
Thanx for the help guys
Sven Ehrich

[jingalls007]

http://forums.offshoreelectrics.com/...ead.php?t=3484

[Rumdog]

set all your gear in the boat, approx. wher yo want it. try to get the cg about 1 inch from the rear of the sponsons. i ran 2x2s 4000mah packs and they fit nicely up in the sponsons. the solinger hydro hw works perfectly on this hydro! dont worry too much about overall weight. i ran an ammo 2600, etti 150 and 2x2s 25c 4000mah and x637/x640 and the boat ran low 50's with very little heat. it is extremely stable for its size. i ran no strut angle. to get the depth set it on a flat table resting on the sponsons and strut. adjust the strut till the tunnel is parallel with the table. that will be a good starting point for ya.

[Blackjack-sven]

Is there a template for the stuffing tube? I don't want to open up the hull too much and have to seal it later. I'd prefer to cut open the hull in the most accurate way possible.

[Blackjack-sven]

A quick hydro setup question. If the rudder is on the right side as mine has been done, what side does the turn fin go on? I'm guessing it's the left side right?

[Jesse J]

Great choice Sven, I know someday I will have one of these hydros also.

In races all rc hydros turn right, except the 1/10" scale. I have always put rudder on left, but that is arguable. If you are wanting to do RH oval, then you need turn fin on right, if you want left, then left. You just want that fin on the inside sponson and then only turn that direction or you risk flippage.

As for stuffing tube placement. My theory is that you want it to exit far enough forward of the transom to allow strut adjustments. You may end up wanting some angle on the strut to keep the bow from lifting too much, remember: the strut depth controls the rear end, too low too loose, too high lots of cavitation/too tight; the angle controls the bow. As for template, yes there is a great description somewhere, but I don't remember where I saw it. I just try to minimize curvature (keep the curve near the motor not the strut) and eyeball it. Then cut out my rectangle, slide the tube through with the cable/wire inside, mount the strut and insert the cable into the motor coupler. this way I am sure it will line up when the JB weld is cured the next day. I use masking tape on the bottom to ensure a smooth surface and use sufficient amount of JB weld to be sure it ain't goin nowheres.

As for weight, I agree, don't worry too much, as long as you have sufficient power and not too much prop you will be fine. My current project is a 26" Elam converted from Nitro and due to space and poor balance, I had to toss a dead nicad pack in each sponson. The thing barely floats (6 lbs) but once it gets up she is pretty good.

These are my learnings and experience, I am sure some will disagree while possibly more will agree. Enjoy, I be watchin.

[Blackjack-sven]

So are you saying that regardless of what side the rudder is on, it's imperative to have the turn fin on the correct side? Oh and if you guys can see the pics well enough tell me if you think the cg is ok. It's sitting on the rear most of the sponsons right now, but it also only has the motor, batteries, foam and hardware in it. As soon as I get the parts the ESC, Servo and mount, and some minor parts like the control rod and boot, the rest of the cooling lines, Rx, and so forth.

[Rumdog]

Looking pretty good man. definately wanna put the turn fin on the rear of the starboard sponson. it will always turn right better anyhow due to the direction of prop rotation. try to get a bent/angled turn fin that is designed for a hydro, not a mono. got any pics of the inside?

[Blackjack-sven]

Looking pretty good man. definately wanna put the turn fin on the rear of the starboard sponson. it will always turn right better anyhow due to the direction of prop rotation. try to get a bent/angled turn fin that is designed for a hydro, not a mono. got any pics of the inside?

Keep in mind that in these pics the only things done to the boat so far is the hardware in the rear, the foam and the batteries. I decided to lock the batteries in place with foam so they don't move at all. The Hydra is from my Blackjack and is only there to see what it looks like. The motor is also only there to see where the motor should sit roughly. I am waiting for parts to arrive before the stuff, Rx, servo, etc. go in.

[Blackjack-sven]

I just realized that one of the batteries will need to come out for me to attach the turn fin. Oh and this is the turn fin I'm waiting for from O.S.E.

[Jesse J]

Looks like you are enjoying this build, good deal. I am a little worried about the length of the rudder bracket, maybe ok, but I always put mine as close to the transom as possible and try to line it up with the drive dog. BUT, I have asked numerous times on the importance of the position of the rudder with no response. You may be just fine. I have noticed that rudders can come in several set back distances, with hydro setups being closer. It might be worth getting another rudder bracket that is set back less and see which handles better (something I would like to try).

that turn fin looks GREAT!

Rock on man, I love these boats and watch your build with pleasure!

[Blackjack-sven]

The rudder was sitting around so I decided to use that one. I was hoping to have the rudder right in line with the prop but this was what I ended up with. I'm going to try this rudder out but I will get one that (hopefully) I can setup both very close to the transom as well as right next to the prop so I can see what works best. I'll do a writeup on all three systems and post vids of the runs as well in case there is a speed difference or handling differences.