My UL-1

[jfrancisco892]

This boat is really starting to annoy me. I have put the batteries into the sponsons, put in an airdam, had a custom turnfin made, run negative pitch on the strut, and it still does not run well. It is not stable in the least bit, and if I get on the throttle it is just a matter of time until it flips. The electronics run hotter than they should with a 42x55 prop even though there is no strain on the driveline and I have opened up the rudder and enlarged the inlet and outlet holes for the water cooling. I have done everything under the sun with this boat, and I can't help but feel like this boat is a pos. If you have any ideas on how this boat can run well let me know because quite frankly I am pissed and extremely frustrated.

[slyman]

Pictures Please. Let's see what you have.

This boat is really starting to annoy me. I have put the batteries into the sponsons, put in an airdam, had a custom turnfin made, run negative pitch on the strut, and it still does not run well. It is not stable in the least bit, and if I get on the throttle it is just a matter of time until it flips. The electronics run hotter than they should with a 42x55 prop even though there is no strain on the driveline and I have opened up the rudder and enlarged the inlet and outlet holes for the water cooling. I have done everything under the sun with this boat, and I can't help but feel like this boat is a pos. If you have any ideas on how this boat can run well let me know because quite frankly I am pissed and extremely frustrated.

[jfrancisco892]

Of what?

[longballlumber]

James,

As we have talked several times at the pond, when this hull was in its original design phase they were using NiMh's and the boat was running low 40's. During our club racing heats you’re pushing the boat into the high 40's and running lighter Lipo batteries. You are going to need to start changing some of the geometry that we've discussed and I have shown you on my boat in order for the boat to be more stable. Assuming that you’re going to continue racing with us at the Shelby Park pond. I would suggest sticking with the UL for the rest of the year and spend the winter putting together a more suitable hull for competitive racing. This is only my opinion, but you have quickly out grown the UL-1 and its performance.

Keep this in mind though... The faster you go the harder it is to keep ANY boat on the water.

Good Luck,
Mike Ball

[jfrancisco892]

Thanks Mike I appreciate all of your help. I will do the modifications we have discussed and that should help, I would just like to get some more results for all the time I have spent with it, but I do understand the limitations of the hull. Once again thanks.

[slyman]

Of what?

Turn fin from and side.

Transom showing the prop and rudder from the prop and side.

Air dam from the front and boat turned upside down.

Top view of the guts in the bathtub.

Is this all stock besides the airdam and the Prop?

Is the prop sharpened and balanced and if so where did you get it from?

What batteries are you running?

[jfrancisco892]

All stock electronics and hardware other than the turnfin and prop, the prop is sharpened and balanced with an ose prop balancer, 2 2s grimracer 5000mah 40c batteries. I dont have a good way of taking pics but the air dam is progressive and reduces the height of the tunnel by about 3/8" at the start of the tunnel. I'm pretty sure the hull is just getting to its limits.

[stadiumyamaha]

A ul-1 in the high forties to low fifties is a hand full. I've gps'd one stock with prop change at 52 but it's not like it was running that speed the whole time. my best speed and handling came once I made sure the strut was neutral which was done by bending the stuffing tube somewhat.
IMO that boat just wasn't made for those speed and mine started cracking at the seems.
I'd get a fe30.

[jfrancisco892]

That's what I was thinking of.

[LarrysDrifter]

I have this for sale. I am firm on its current price.

https://forums.offshoreelectrics.com/...ale&highlight=

[m4a1usr]

I'm pretty sure the hull is just getting to its limits.

Maybey with how your hardware is setup, but its been known to go into the 60's before becoming a nightmare. Any chance you read the stickies at the top of the page? Some good advice there. I do have a couple questions though. Have you checked the hull for front to back trueness or side to side? You have to take off the turn fin and make sure you have a reasonably flat level surface. With both sponsons touching the table put some type of spacer under the strut to raise it so the prop clears. Doesnt need a lot. Maybe a 1/2" block of wood. With both sponsons flat, measure the outer edges of the transom down to the table. Both should be the same amount off the table. If one is higher than the other you have a warped hull. That will effect top end stability which you seem to be having issues with. The reason I know this is because my first UL1 tended to exhibit what your describeing and it took me a bit of time before I got it figured out.

Second question is have you changed the strut depth or confirmed its set to the stock depth? You said you changed strut angle. Any chance it moved towards the hull? That would be decreasing the strut depth and that will certainly change the ride angle. IIRC the strut depth should be set 1 to 1 1/16 with a 40mm prop. My current UL1 is running a 42mm prop and its set to 1 1/8. But my strut angle is set to neutral to the ride angle. But the reason for that is my rudder bottom is rounded (minor lift) and the rudder face angle is set with the bottom slightly inwards towards the transom. In other words it wants to put some minor down force on the transom. I know I'm in the low 50's. And I run an air dam as well.

John

[electric]

I would suggest that if you are racing that you move to a better platform(boat). For P-limited Hydro I would give the Insane FE30 a try. I have also owned a UL-1 and while it is possible to have it win races it will always have a tendancy to "fly" at race speeds and rather than frustrating yourself, it might be a good time to consider a boat that is a bit more stable at 50+. Others to consider are the Phil Hydro, cybertxt's hydro.

[slyman]

I consistently run between 55 and 61 MPH. I am running 6s 40C 4,000ma LiPo's, a 3674 1700kv leopard, Turnigy 120 ESC, and a cupped B&S X440 Octura prop. My strut is set at 1 1/8" with a very slight negative angle, the rudder has been sharpened and the end of the leading edge has been rounded off. The rudder is set between 35-45 degrees away from the transom. The turn fin is straight and true to the sponson. The sponsons have been sanded flat and the rear of the boat has also been lightly sanded in order to break the surface tension. I also have an airdam set back 1" from the outside of the leading edge of the tub and and 1/2" high sponson to sponson. My runs are between 3-5 minutes. Make sure your turn fin and rudder are straight as they are prone to bend at higher speeds.

[longballlumber]

Maybey with how your hardware is setup, but its been known to go into the 60's before becoming a nightmare. Any chance you read the stickies at the top of the page? Some good advice there. I do have a couple questions though. Have you checked the hull for front to back trueness or side to side? You have to take off the turn fin and make sure you have a reasonably flat level surface. With both sponsons touching the table put some type of spacer under the strut to raise it so the prop clears. Doesnt need a lot. Maybe a 1/2" block of wood. With both sponsons flat, measure the outer edges of the transom down to the table. Both should be the same amount off the table. If one is higher than the other you have a warped hull. That will effect top end stability which you seem to be having issues with. The reason I know this is because my first UL1 tended to exhibit what your describeing and it took me a bit of time before I got it figured out.

John

I agree with you ideas here John. Assuming the hull is "tweeked" do you have a reccomencation on making it true again? I am willing to assume that most UL-1 hulls are "tweeked" right from the factory, since they are mass produced.

Later,
Mike

[detox]

Any UL-1 will handle badly if water is too choppy. Wait for calmer water conditions before you run.

You do not need airdam for low fifties.

I like a deeper strut setting 1 1/8" so sponsons will ride wetter on the water (wetter is more stable). I also like downward 1 - 2 degree angle of strut to keep prop spray down in water.

A thin and verysharp m440 works verywell (easily 49mph). I also like the x442. Learn how to add cup at the tips for faster speeds.

Read and understand your manual. The UL-1 is probably the best hydro to learn on.

[zpr25]

Just slow down a little bit its made to do just that;;;;;;; build one from scratch its gets better belive me][][][';';'.,.,.

[wayne middlemiss]

guys i can share with you all the first hand knowledge of how well these boats are built.

firstly i have done and still in the procces of making a mold off my own boat that bustedt up with the first and last blowover i had.

the layup of the glass work is crap it is done useing various different mattings from satin to chopped strand all peeled layers so it is not quality in any sence of the word.

secondly the glass is only stippled in not rollered as you would expect full of air in the layup, we are realy talking chinese work here so i would doubt that a craft would know whats going on since they come pre painted and truthfuly the paint holds them together.

3 rd when the 2 halves are joined they are done with large blobs of resin talc mix so the blobs are the cause of the deformation in the air traps of them.

im not crapping on aq at all just enligten you all as to what you dealing with as per boat , and if your rubbing it back to repaint it go easy on it as you may rub completly through . these boats are sold here in aus @ over $800 ea so that is my reason for doing a mold to build a good hull of my own expectations.

[Doby]

So you are making a mold of the UL-1 hull?

[wayne middlemiss]

yes and mainly to prove some theories i have about ul-1 and not looking to sell from it either.