Miss Geico Race Prep

[Darin Jordan]

Once the sanding of the initial filler was done, I did some additional filling with spot filler to really clean things up and sanded this down as well.

With all the sanding done and everything cleaned up, I made sure that the sponsons sat true on my setup board. Inside edges of sponsons should rest cleanly on the setup board with minimal or no daylight under them from the transom forward for a few inches in front of the first vent. Sharp and true, cornering should be rock solid.

I applied a couple of light coats of primer, then a couple of coats of Duplicolor Bright White.

Edges are now very sharp and clean.

[Darin Jordan]

Time to work on the power system, just to add some reliability.

I replaced the motor leads with 5.5mm contacts and the battery leads with 6mm. I take the Y out of the stock ESC, instead Y-ing the batteries together with their own leads (connect them in series).

I replaced the coupler with an Octua coupler and added a thrust washer. To install the coupler, I had to increase the width of the flat on the output shaft with a dremmel. The sloted holes in the motor mount allow it to be slid forward to get the additional clearance for the longer stub.

Add a little velcro to the battery trays, and we're ready to go.

[Jeff Wohlt]

Octura also makes a short version of the 5x150 coupler that will fit easier.

Looks good Darin. Doing about the same on mine. Going to run a Leopard 2200 and 4s and start with a x445

[ron1950]

so will flatening the botoms out stop the bounce or just make it turn better?

[Darin Jordan]

Now... for the RACE report!

We had our final PSFEMBC Race today, so I took the Geico to run in Offshore.

Leaving the strut set in it's factory delivered location, I put on an X645 and a pair or ThunderPower 45C 5000's, and went out for a test run.

About 30-seconds into the run, the boat slowed considerably, then just stopped. When I got it back in, the driveshaft (an Octura replacement shaft I had fitted to it previously, but forgot to mention in my prep comments...) was siezed into the bushings on the strut. I had greesed it VERY well, but apparently the stub was a tad too tight a fit.

I ended up pushing out the bushing and fitting it with a makeshift Speedmaster bushing setup, which wasn't ideal, but would get me through the day.

Headed back out and made a few laps. Boat seemed OK on speed, but scrubs a LOT of speed in the turns.

I moved the strut down slightly, and went out for the first race heat. I nailed the start and ran in the lead the entire heat, but the boat was still not fast enough. I won the heat because of clean driving, but need more speed if this is going to continue.

For the next heat, I moved the strut down and put on a modified X547, with a bunch of cup and pitch added to it, and cut down to 44mm. Boat was faster in the straights, but still not fast enough. REALLY pinned itself down in the turns. Moving the strut down was the wrong answer. It raised the rear, but pushed down the front.

I was running out front, by a good margin, and was trying to run "pivot" turns instead of trying to carve them smoothly. MAN this boat can corner hard!

Unfortuneately, I pivoted it a little too hard at the wrong moment and hit another wake, dropping into the trough and tripping on the outside of the sponson. Boat flipped and I was done.

Good news is, however, that it was sitting out there for 3 laps, and when I recovered it, not a DROP of water had gotten inside. I only used a little piece of tape to hold down the hatch, but otherwise, it was all the secondary hatch. Nicely done!

We would up racing early due to the team having to calculate season points for everyone. While they were tallying up the points, I went back to the bench and put a Prather 230 prop. Tired of messing around. Let's see what this thing can really do.

Boat was QUITE a bit faster with this prop. Still not quite where it needs to be, but way quicker and still cornered on rails. VERY easy to drive too, and rock stable in the turns. A little bit of bouncing still, but very drivable and lots of tuning to do.

After about 2-minutes of running the motor temps were 117-degrees...

[ray schrauwen]

Darin, this may have a close match for the green, either the Lime green or Candy lime green with just the righ base coat.
http://www.tamiyausa.com/product/cat...d=61500&page=1

I really like their paint, expensive but, nice!

[Darin Jordan]

So... where to go from here.

First... I'm not completely sold on the rudder directly behind the prop. It works, but I think it's really scrubbing off speed in the turns. We discussed it today and Scott Bickford suggested that perhaps moving the rudder back from the prop a bit more might help to get it out of the initial thrust cone of the prop.

I'm considering doing this, or moving the rudder off to the side. Neither NEEDs to be done, I'm just thinking that perhaps that's something to consider for a future tweak.

I'm going to remove the hardware and "V" the bottom surfaces of all hardware the encounters prop spray to allow it to pass by the hardware without introducing additional lift.

Seeing as I've seized the bushings in this strut, I'm either going to replace it with a SpeedMaster or ??? strut, or I'm going to modify this one to correctly accept a SpeedMaster bushing.

Otherwise, I think it's just a matter of getting the balance right, playing with the strut height, and honing in on the right prop/setup combo.

Can't wait for the offshore races next season!!

[ron1950]

so what did the bottom fixing do or suposed to have fixed? just wondering if i should do it or not...my bigest prob is the bounce right now ...i used a 215 prop and ran well but hopped like a rabbit

[Darin Jordan]

so what did the bottom fixing do or suposed to have fixed? just wondering if i should do it or not...my bigest prob is the bounce right now ...i used a 215 prop and ran well but hopped like a rabbit

Cleaning up the bottom makes the boat run more efficiently. It allows the water to cleanly break off the wetted surfaces. Cleaning up the inside of the sponsons and making them sharp enhances the cornering and getting rid of the recesses in the sponson bottoms gets rid of "suction cups" on the ride pads... making them run more consistently and faster.

From what I could tell today, the "bounce" is cleaned up by proper balance with the cells, strut position, and prop... Listen to some of the guys posting here and you'll get there. I had mine bounce a little too, but would switch props and it would subside, so I know that it's setup.

[ron1950]

thanks man.....i can tell ya the stiletto prop doesent help it out on the bounce with strut in factory trim....lowered it and will see what happens tomorrow if weather is good

[Darin Jordan]

Forgot to mention... I also used 2-part expanding foam in the front of the sponsons, which got rid of the little bit of flexing in the tub in this area. I did this BEFORE I started the blueprinting on the bottom. You can see the foam in this pic.

This added a little more weight to the nose, which is why my CG was a little more forward than I would have liked, even with the cells all the way at the back of the boat.

I did, however, talk to someone this evening who runs theirs with the cells at the front of the battery trays (6500 cells at that) and theirs handles great, so it's all in getting the right combination for your running conditions.

[Darin Jordan]

thanks man.....i can tell ya the stiletto prop doesent help it out on the bounce with strut in factory trim....lowered it and will see what happens tomorrow if weather is good

The Prather series props have a good deal of lift, but I ran mine with a Prather 230 on it today and it was pretty good.

I'm wondering if some of the bouncing could be coming from prop spray hitting the bottom of the hardware in the back?? There are some wide flat surfaces there that are in a direct shot of the thrust cone... Hmmmmmm... I'll have to take a look at that.

[blackcat26]

Darin, I thought I would post this in here to help everybody who is following this thread. I made a little mod to the rudder bracket so it's easier to take off. (without having to take the bolts all the way out) Used a bandsaw and a file to get the edges cleaned up. Works good and bolts stay in the bracket instead of on the floor where most stuff ends up in my basement.

[ray schrauwen]

Why not just make a quick release rudder break-away bolt and then just pivot the rudder?

[blackcat26]

I was gonna do that but the rod connector does not like that much movement.