Nitro Hammer doing barrell rolls

[DaveG]

Took the hammer to the lake last weekend. The real lake, not the small one near the house, and found out that it really does not like real boat waves. It's really cool to get it so far out that it's real tiny and to buzz it by (200' or so) the bass boats - they hated that! But, hey, they were in our cove, I wasn't in their's.
I only had one problem with the boat. It would occasionally try to flip sideways, kind of like prop tourque was trying to flip it over. It was so bad that at one point the boat actually did a barrell roll and kept going. A neat effect but kind of unnearving. It is turning towards the side with the antenna. I tried to bend the trim tab on that side down and the other one up but it would still do the same thing. It did not do this the last time I had it out and I did not change anything since then. Any ideas on why it's doing this and how to stop it?
Thanks
Dave

[scorpien boats]

hmmmm, that's weird, maby the waves were bigger one day, or maby the hummidity was up/ down one day and made the mixture leaner which gave it more power, i dought it but its the only possibility I can think of.
If it keeps happening you might want to get some bigger turn fins

[DaveG]

It was late in the day and the water was pretty smooth. Not glass but not rough. The turn fins are the stock ones and I have not done anything like trimming them or anything. I do have it tuned in pretty good, both response and temps are real good. It's got a new, stock prop and no loose hardware.
It only does the roll thing on a full throttle run. If I chop the throttle before the prop gets out of the water it usually just settles back down. If I wait a bit to long, like the instant before the prop comes out, it ends up upside down in the water. If I leave power applied, that's when it barrell rolls. Also, it does it with out much warning - no chine walking or bouncing around.
Anybody else with some ideas? Please!
Dave

[CFRACR]

For one the Hammer is top heavy to the left side when facing the boat. The Stock radio box adds weight high on the CG. The batts & receiver on that side also add to the weight. Thats why it rolls to that side when it comes out of the water.

Two things that can be done....

Changing the radio box situation so that the batts & receiver are more in the center. (basically a radio box overhaul) Also changing the batts to a lighter re-charge pack helps too.

Keep the trim tabs even!!!
If you need to use a small level do so.
Softly and gently bend them down(even)in small increments. Keep making that adjustment until the boat is riding nice (not plowing & not bounching all over)
Thats where the tabs will need to stay for the water conditions of that day.
The tabs will need to be adjusted every time the water conditions are different from the last time you ran it.
MINOR CHANGES (1/16-1/32) IN THE TABS HAVE EFFECT!

Hope this helps :)

[DaveG]

The bit about the radio and battries makes sense. I don't understand why the tabs need to be kept even though. It seems to me that if it's riding low on one side deflecting that side's tab lower should bring that side more in line for a better riding attitude. That's how they work on 1:1 boats anyway. But, I will try your suggestions tonight at the lake.
Thanks
Dave

[dadyo39]

Took the hammer to the pond for my daughter to run and was having the same problem. It is fine in the straights or turning left but when turning right the boat would want to turn its self over :eek: put the tab down more on that side . It has never done this before. Water was flat. stock prop stock rudder running 25% nitro, the deck is cut also. any ideas :confused:

Thanks Mark

[yellow-hydro]

my N-hammer does the same thing , only at full blast, when the boat is mostly up on plane and just barely touching the water,
hit a small wave which even lifts it out of the water, and it rides on its side about 45 degrees for a while and qiucly slaps back to normal position, if the waves are slightly bigger it rolls.
I think what happens, as the boat gets semi airborn the prop comes too close to the surface where it may allows the engine to rev more than it usually does, giving the prop some extra power to lift out of the water, pushing the boat to its heavier side (left )

[wavewaker]

Took the hammer to the pond for my daughter to run and was having the same problem. It is fine in the straights or turning left but when turning right the boat would want to turn its self over :eek: put the tab down more on that side . It has never done this before. Water was flat. stock prop stock rudder running 25% nitro, the deck is cut also. any ideas :confused:

Thanks Mark

i noticed mine more leaning towards starboard, i tried counter weight placed on port side, it helps though, i placed it below the tune pipe next to transom.