Darin's ProBoat Miss Elam Race Prep

[eboat]

Darin have you had this in the water yet ??

[Darin Jordan]

I've made a couple of small updates, based on data gathered from the two previous races.

First... At the last race, I decided after three heats of the sponson tips trying to see if the sun was still there, to strap on about 8oz of lead to the front wing. Boat instantly settled down and was able to be driven HARD around the entire course... handled great... SO, I've added about 6oz of lead into the front of the hull. I did this by VERY carefully drilling two 1/4" holes through the side of the sponson and ALL the way through the wing (it's hollow... just had to drill through the 2-part foam I had put in there) to the other sponson. I then slid two sticks of 1/4" fishing lead across the front of the boat, through the wing. Each stick weighs right at 3oz. The holes through the sponson didn't turn out that clean, due to the brittleness of the glass on these, but I've filled them in with epoxy and will clean them up tomorrow and hopefully be able to cleanly touch up the paint there.

For those of you who are "weight-a-phobes", don't be concerned... a light boat doesn't do you any good if you can't keep it on the water, and we have plenty of power with these motors. I'd rather be heavier and be able to run all out than light and have to feather the throttle the whole race...

The problem with these pickle forks is that you simply can't get the CG right with batteries. You can't get them far enough forward with most designs. Since the Elam is 6oz lighter or so than the UL1 in stock trim anyhow, I don't feel like I'll be giving up much, if anything. I actually feel like this will gain me speed, because I'll be able to get back to some real props, now that the nose will stay down when I need it to.


Second... I've made a new turn fin. Just about 1/4" longer, and a longer chord length to give it more area. It's made from .060" 7075 T6, and has two slight bends in it to hook it at the bottom, one 1/2" up and the second 1" up... Not quite as hooked as the stock one. Sharpened and drilled up. Should provide a bit more control in the corners when the water gets "racey".

I'll test all this on Sunday and let you know how it works out.

[Jesse J]

Great idea: the weight in the wing! I have since thrown two dead nicad packs in the sponsons and it ends up just about 6 lbs! I may try your trick - weight way up front. I really do love this hull, looks are top for me.

Have you noticed any reluctance to turn in this hull? I may just not have enough servo throw, or maybe its the turn fin. I am curious to see how this new fin works.

[saleens7]

i just read through this whole thread and i have to say im impressed.....looks like it took a lot of work to get the hull to be race worthy.....goes to show just how well built a race hull would need to be....

[Darin Jordan]

i just read through this whole thread and i have to say im impressed.....looks like it took a lot of work to get the hull to be race worthy.....goes to show just how well built a race hull would need to be....

Please keep in mind what I said at the beginning... a LOT of this work is just because I have a certain way I like things to be. The most important thing I did was to blueprint and add the ridepads... Second would be the adjustable strut modification. Everything else was just for ease of maintenance and to keep things dry... I guess also to make it survive under race conditions in case it gets hit or flips...

Hopefully some of these ideas will make it into future offerings... I may have some pull with that!

[Darin Jordan]

Have you noticed any reluctance to turn in this hull? I may just not have enough servo throw, or maybe its the turn fin. I am curious to see how this new fin works.

Mine turns fine, but the stock turn-fin doesn't have enough area, and is a tad too shallow... at least on mine it is (keep in mind, I made a new bracket and the ride pads added a touch of sponson depth...)... A longer chord and a tad deeper will certainly help. I was having trouble holding lane one at speed... this should certainly help.

Also, I'm running a stronger Hitec HS-225MG servo, so that may help as well...

[Darin Jordan]

Epoxied over the two holes in the sponson last night, and sanded it smooth today. Just going to tape over it for now. Still need to find the appropriate touch-up paint for this kind of thing.

We'll see how she does tomorrow... CG is now right about the center of the turn fin, which is a LOT closer to ideal... Should translate to better race performance.

[rcboatfan]

looks great!!1

[Jesse J]

Darin, did you coat your stickers with a clear coat? they look really good!

[Darin Jordan]

No... they are factory that way... They are starting to peel off where I've been taping the hatch, however, but otherwise, it really does look great.

The weight REALLY helped... boat was really a lot easier to drive... Turn fin helped as well, but I still think it needs to be deeper. I have another one that I started to make that is 3/8" deeper or so. I'll be putting that one on next.

I ended up adding another 2-oz of lead taped up under the center of the front wing... this seemed to really be a good final tweak.. boat was really good in the straight... flat out. I think once the turn fin is hooked up a little better in the corners, it'll be exceptionally competitive... it really goes well.

I think that there should be some great pics forthcoming... Jim Clark was there with his amazing eye and camera equipment...

Oh... and after flipping on the second lap of the first heat, I won the next two, then had a runoff for second overall for the day, and won that too. Boat is becoming VERY raceable....

[JimClark]

Here is one teaser


the rest can be seen here

http://jimclark.smugmug.com/gallery/8321718_esjPP/1/545190424_HGVyD

[saleens7]

I'm still impressed by that camera work of yours.....great pictures of the race

every one of them are desktop background worthy.....

not to mention the detail work of some of those boats too....

[Jesse J]

Darin, what speeds are you getting? I ran mine yesterday, totally unmodified hull but with my two dead nicads in the sponsons (UL1 motor/X640 prop) and she clocked in at 44mph. Dam stable too, with 6lbs she will be reluctant to flip. I still need deeper turn fin as well; I couldn't talk you into makin an extra could I?

[longballlumber]

Darin,

Sorry if I missed it but, are you running 1P or 2P? What is your weight ready to run (w/batteries)?

Thanks
Mike

[Flying Scotsman]

Here is one teaser


the rest can be seen here

http://jimclark.smugmug.com/gallery/...45190424_HGVyD

Jim, as usual stunning photography. Darin, not too shabby on the boat also.

Douggie