Newbe Twin Jet Drive?

[txm37]

New guy here. I am not new to the rc hobby or boats. I have had two graupner jet-2's (29mm) sitting around for a while now and looking for advise as to what they would go good in. For now I will probably power them with the 700BB motors I got with them ages ago. No clue on bats. or esc but will probably try to use what ever I have to save money. I would love to use them in an old cat hull i hull I have but not sure if it will work? The hull is an old kyosho heat wave gp. Any thoughts? Will a cat hull work? Has any one done it? I have seen talk about it but not much else. My goal is to build something fun with what I have or as little cash as possible.

[sundog]

Not to be a poopie-head, but realize that it wouldn't be nearly as fast as a prop driven boat. And running in shallows with a cat might be troublesome. If I just had to do a bi-hull, I would choose a non-stepped hull to keep aeration down. You should maybe sell one to me and use the other in a 22 to 30 inch mono. Or be the first to prove (or disprove) the concept. I know I'll be watching with interest!

[Boaterguy]

Someone tried to start one a couple weeks ago, but it got quickly shot down here on OSE. Cat's just wouldn't work with jets, the physics don't add up. If this were a low speed rescue or cruising boat, that would be a diff. story.

[srislash]

I have built a flatbottom drag style boat with the Graupner jet but it hasn't seen the water yet as i'm waiting for suitable donor equipment.Thinking my Miss Geico stuff here,shouldn't be long though and I'll try and let you all know how it goes.It should be fun at least .

[txm37]

Thanks for the info I will definately keep watching to see what turns up. After glueing up the jet housings I did a little placement testing and I see more than one issue trying to use that hull. Least of which are the steps in the hull. Being only 27.5 inches long they seem a bit over kill and the weight is all in the wrong places. Do the output nozels need to be submerged or is partialy submerged ok? In that hull it looks like they will only be half submerged. I still want to build something with dual jut drives. Dont know why just seems like it would be fun. With that are there any non stepped cat hulls available or would dual jets work in a v hull?

[sundog]

No, the nozzles do not need to be submerged. They'll work fine out of the water. 27" is a good size boat for those nozzles. The intake ramp doesn't need to be fully aft as Diegoboy showed with a Fastech conversion he did a while back. The suction will help keep the hull on the water. Most older cat hulls are non-stepped.

[wparsons]

The problem isn't just the steps, you also need a flat (not angled) surface for the intake. Every cat I've seen has some angle on the sponson bottoms which would leave a good portion of the intake out of the water when on plane.

[srislash]

Just a suggestion,but how bout a yacht style hull. Ocean LED has some vids that will fill your head with ideas.Just a thought since the propulsion won't make it a screamer but it will have the push.