Hospital Hop...how to stop it?

[Doby]

Wait wait wait.. i get it I get it i get it...

Andy.. play this game the way you see fit.. I can tell you now however.. Im not the kind that’s going to comment on how your designs for Proboat work. Its just tacky and not all that professional.. especially when you work for a company (Horzion) that makes products that are in direct competition with ours. Im not going to do that to your boats.. but again its your head.. do as you please.

ROCK ON UL-1 Drivers.. lets get some heat wins.

Grimracer

So Andy works for ProBoat?

If true, it would be nice to know who is affiliated with what company so any advice/ comments can be weighed appropriately.

[Grimracer]

....ummmm.....back to my questions at the end of post #23 please. And can ya show me what you mean about the turn fin setting with a pic or drawing.

Thanks


(I didn't know Andy is affiliated with Pro Boats)

Youz guz need to duke it out with your products on the field of battle...not this thread please!

lets see here.. if this works on this old dog..... sorry about the ugly pic.. its just to get the point across.

Grim

[Capt. Crash]

Thanks Mr. Racer...

...that is a big help.....now one more time....where exactly should the CG be with the boat buttoned up and ready to terrorize the pond.

Crash

[Capt. Crash]

Mike,

That's so the bottom of the rudder doesn't become a planing surface, right??

That's a mighty small planing surface! I'd think it might have more to do with turbulence created there.

[Bill-SOCAL]

So Andy works for ProBoat?

If true, it would be nice to know who is affiliated with what company so any advice/ comments can be weighed appropriately.

Well in the interest of full disclosure then, I am a member of Team Futaba (Air) as a Field Representative. I am not paid, receive no other compensation and pay for everything I get (but I do get a decent discount). I do get free service (hardly ever need it ) and a free Team Shirt each year. Sadly some think that we Team members will compromise our integrity for the sake of that free shirt.

Oh well. Like my signature says on another forum - "Ignore me - I get a free shirt!!"

[Grimracer]

anytime dude..

Capt.

Setting the CG at 3 to 3 1/4" back from the sponson backs will get you very close. Typically on a good race boat the CG is around the center of the back of the turn fin. One of the reasons my turn fin design is swept.. allows better turning on a wider CG range.

The bottom of the rudder can make lift.. more then you think.. also remember to sharpen the rudder.. (lift lift lift)


Grim

[Darin Jordan]

The bottom of the rudder can make lift.. more then you think.. also remember to sharpen the rudder.. (lift lift lift)


Grim

Thanks Mike... that's what I thought... I recall reading that in an article on making Monos work (I think by John Finch??? )...

[Capt. Crash]

Lot's of good stuff in here to help me and the lurkers out there....you know who you are!


Thanks again everyone.

[detox]

Mike, Good info concerning prop, turn fin, COG, and rudder sharpening .............THANKS!

While sharpening the rudder you will notice water intake hole plugged at bottom of rudder (red arrow) with what looks like epoxy. Be sure to plug this area again using epoxy (JB Weld) if port is exposed after sharpening. I removed red area of turn fin only.

[Jeff Wohlt]

Some of the Chine walk can be attributed to flat sponson design with too much angle. You may be getting your walk from the light front end and the motor/blade torque as the front is light it will try and twist the boat to the right then it reacts after hitting water and then the reaction occurs...left side hits and pushes it back up. No doubt this is a faster design than a low angle sponson but handling will be the issue in certain water conditions. You are packing a lot of air in that hull riding high in the front but the tail also rides pretty high so I doubt that the hull is not exiting the air.

Are you running the 3 blade prop?

As Grim noted...that strut angle is waaaaay off but that will push the nose down and make the sponsons run wet. You have to have a certain amount of area that is in contact with the water. Should be fine on smooth water but waves or other boat wash will make it hard to handle.

[AndyKunz]

So Andy works for ProBoat?

If true, it would be nice to know who is affiliated with what company so any advice/ comments can be weighed appropriately.

No, I work for Spektrum supporting aircraft stuff almost exclusively. I own a Miss Elam and hope to get it on the water as soon as it melts.

For the record, I also told Mike at the IHobby show that it's a really nice looking boat and I would like to have one. He might think I'm dissing him, but I'm not. I just happen to come from a different school of Sport/Scale hydroplane design.

Andy

[Capt. Crash]

Are you running the 3 blade prop?

Yes...that's all I've run. The stock prop and setup did not do the Chine Walk...the 40X52/3 and stock setup (7/8" depth) does and so does the 40X57/3 @ 1"strut depth. I've not tried the setup I took the picture of (1 1/16" depth)...it was next on my agenda. I may have try it just to see how she runs.

Thanks for the explanation on the reason for the Walk...that makes sense to me.

[Capt. Crash]

Some of the Chine walk can be attributed to flat sponson design with too much angle. You may be getting your walk from the light front end and the motor/blade torque as the front is light it will try and twist the boat to the right then it reacts after hitting water and then the reaction occurs...left side hits and pushes it back up.

I just checked my Center of Gravity and it appears I was tail heavy. I'm sure the 3 oz GPS isn't helping by being aft. I moved it up between the batteries and slid the packs all the way forward and I am just about balanced right. I wish the ESC wires were just a little longer. I have to lay the connectors on top of my GPS window...that's why I went AFT in the first place. I may move the ESC forward a little to fix this. My 5250s only weigh in @ 241 grams each so the movement of things forward should help compensate.

[LuckyDuc]

Good stuff gents! Like Capt said... When possible, please post illustrations/pics for us noobs. It helps us visualize the advice better.

[LuckyDuc]

BTW I really appreciate the info on the location for the C of G range.