33" Fountain Setup Issues

[D. Newland]

I got a quick 1st time run done on Thursday, then more on Sunday.

Thursday was calm, and my starting COG was too far back. Boat was way too loose.

I moved the battery's further up 1 more inch for Sundays run. It was windy with gas boats chopping up the water even more before my practice runs. I was able to tighten the boat up nicely with the tabs and the new battery placement.

It turns well, but can't make a hair-pin turn like my other mono's. The shallower V probably has something to do with it, but I'm going to try a few more turn fin options/trim tab settings to see if I can get it to be more responsive. This may be a tall order, but it's necessary if this boat is going to race an Offshore Course.

I am not getting any hop in the turns, either left or right. I may be running less power than you, but not sure. UL-1, X442 with an average amp draw of 60 amps. Approx 840 watts.

[scooterP]

You may have cured your hop when you leveled out the ride pad. I'd be anxious to see if it didn't hop with more power. I'm running an 8XL with a S220 prop.

I don't have any data logging equipment yet so all I have to go by is what Fecalc states, but I know that it is not the most accurate tool in the world.

I'm running 2 4s1p 4000mah packs in parallel. Fecalc says it pulls around 143 amps. I do have a gps that states straight line speeds of anywhere from 44 to 48mph.

I really don't mind tweaking things like this to get them "just right." Hopefully between what you come up with and what I can find out with mine, we can get a solid performing mono.

[D. Newland]

Taming down your setup may make your tuning easier. FE calc may be pretty close to your amp draw and speed...maybe a little generous on the amp draw but I bet you're a solid 120 amps anyway. You're running a very hot 4S setup in a boat that may not be up for it, even with the work I've done to it.

When you're ready to test it again, IMO prop down to an X440 or X442, or use a slower motor like a 9XL or 10XL.

[scooterP]

I have a x640 that I was going to try next on it actually..... I'll have to pick up some other props sometime but the budget thing is kind of slowing me down. I did have a 9xl in it in the beginning, but it was the cheaper HK brand and I overheated it and the rotor became demagnitized. I then put in the Feigao 8xl.

I can't really complain about the overheated motor.....I was feeling a little froggy and ran it on 6s for a couple of passes It GPS'd at 61mph.

Even with the 9xl, the handling was still the same. I even tried it with a Y536. Other than taking a long time to get on plane, handling still was same as usual. I do know that like you said, it's not going to be a boat that will do a hairpin turn for sure. I have learned that if you start into the turn easy on the rudder, you can then add a little more as the turn progresses.

At any rate, it's not boring to drive at all. Keeps you on your toes. My 25" is down right boring without anyone to race. It rides like it is on rails.

[scooterP]

Hey again, Did some running/testing over the last few days and this is what I have found.
Dropping the outside tabs a little makes it turn MUCH better. Shaft is at neutral to just a little angle.
I also have to have the fins angled down a pretty good bit to keep it from sliding out in the turns.
It's slowly but surely approaching the drivability that I like. So far this has been a very educational project. I have learned more about boat setup with this hull than anything else I have. Now if I can just find some folks to race with.....

[scooterP]

I know this is an old thread, but I have still been tweaking the fountain looking for that sweet spot. I think I may be close now. I moved the stinger up to where the stuffing tube exits the transom 1/2 inch above the bottom. Takes a little longer to get on plane, but has helped the handling in turns a great deal. It will still hop a little, but not near as bad as in the beginning.

My CG is a little aft of 33%.....maybe by an inch. I have dual trim tabs on it and the inner ones are pretty much even with the bottom of the boat. The outers are about 1 deg down or so to cut out the high speed tendency to chine walk.

It still looks like it's running a little bit wet still, so I'm going to tweak it some this afternoon. Hopefully I won't have to send the rescue boat out after it again........