A few pics of the BJ

[obrien]

just a couple of pics from yesterday.

thanks to Avanti27 for taking these.

[obrien]

couple more

[Avanti]

sweet pics who took them :P

[treystoys]

Haha I see how your running 50 now!! Loose as a goose! Did you remove the battery trays? And whats your CG set at?

I ran mine today, no records, but it ran well. I got another 46mph run with an x442, and the boat performed really well. I also tried a detounged 1742, and got a sliggish 42mph out of it. When I got back I reworked the 1742 for some needed bow lift. I'm not expecting much out of it, but it can't hurt. Back in my gas boat days, we used to run modified cleaver blade props on V's and cats, with good results, so I had to atleast try with this one.

ttyl

Trey

[obrien]

I tried a v937 but it didn't work.

Yes I removed the battery trays. I did that before the boat ever hit the water. I need to measure the CG just to see where it is. I know its certainly not where it should be. I back a bit. I will measure it in the morning if I get a chance. I know that when I originally started playing with the setup, if the batteries are in the stock location the CG is in the middle of the 2nd running surface. I would have to quess mine is back in the last running surface.

I am sure that my current setup wouldn't be much good for racing, but since this hull doesn't turn that great, I figured I would see just how fast I could make it run. I put the turn fins back on tonight so I can try to get the boat to turn better. We shall see just what happens.

[treystoys]

Yeah, I think I'm gonna rip my trays out too, I had a blowover twice today, and it broke part of one anyhow. I'm with you, the boat may turn decent at OE speeds, mid 30s or so, but approaching 50, it needs plenty room to get around.

I doubt the fins are gonna help much, the problem you'll have is that with two of them on a cat, they are both still in the water when the hull turns, which will cause the boat to trip and tip over on the fin opposite side of the turn. Now, if you wanted to make it so it'd turn well to the right as in an oval set up, the one fin on the right sponson would probably work pretty good. Trust me, I had a Drifter S about 5 years back which was very similar in bottom design and dimension as our boats, and I tried small fins on the inner rear of the sponsons, fins on the transom, and went as far as modifing the bottom rear of the hull to get it to turn. Nothing worked. The problem is in the width and the padded hull design. If your gonna make a narrow cat a turner, the bottom of the sponsons need to be smooth, with about 10 degrees of dihedral, sharp edges in the tunnel and a soft chine to keep it from tripping. I plan to build a copy of the BJ using my own bottom design but time is hard to come by with a wife 2 kids and the job. I'll have to post some shots of the boats I've scratch built in the past, mostly riggers, but a few tunnels and monos as well.

Oh well sorry for side tracking...just loosing myself in the past...ha!

Later guys

Trey

[obrien]

sounds good. I would love to see some of the stuff you have made. I keep thinking about making my own hull, but I doubt I will ever get around to it.

I will play with the 2 turn fins as well as a single just to see what she does.

[obrien]

With the back of the batteries at the 2nd step, the cg is just shy of 8". For the top end runs I have been doing, the cg has been just over 6"

[zero9046]

how do you guys measure the CG? i understand the concept but not sure on how to go about doing it. do you just balance it on fingers or something?

[obrien]

I just hang it with a string under the hull