Hammerhead .48 (project strategy)

[Hammerhead]

I just can't stand not making something. Give me a minute with my hands in my pockets, and the next thing you know, I get some idea that will keep me busy for the next month or so. Well, Here it is.

The Hammerhead .48 Strategy.

The idea behind this is just as the name implies. Strategy. It will be an Oval time trial racing rigger. The JMPBA rules say, B class Hydro may be no more than .46 and C hydro may be no less than .47, and no larger than .91. There are very few engines in between that will kick it up like the O.S VX-M .46. Too bad that it is too small for C Hydro.

Not any more. Thanks to Mark James, I was able to get a new VX-M .46 for a very reasonable price. I had one of my racing buddies machine a crank shaft for me that will bump it up to .48. Do you get the picture? Now I can run C Hydro ovals with a B hydro rigger, and a O.S .48 VX-M. Traffic will not be an issue.

Here is a pic of the frame work.

Hammer

 

[Hammerhead]

Here is the picture of the crank shaft that I will be using. I will have to get the inside of the case machined, or the bottom of the connecting rod will rub the inside of the case.

Hammer

 

[_laxmasta2039]

wow,

and though i had the bug bad! good luck, that sounds like a hard task to complete, it's always harder when you're doing a rare [or somewhat rare] design....after watching the hammerhead .12 progress [and hopefully getting ready to try it myself] my insticts tell me this'll be an awesome boat. a boat completely specialized to do one thing, in this case run oval time trials in C class, can usually beat the pants off of a general purpose type boat competing with it....it's gonna be interesting for me seeing what's different in the design when you dont have other boats on the course with riggers.....

Joe

 

[Hammerhead]

Actually Lax!

Not much different than the .12. It will be 12 inches longer, though. The material and construction will be basically the same. The tub will be about 1/4 and inch taller. From the front of the tank room forward will be all foam. The sponson booms will be 9mm instead of 5mm, it will have plumbing in it for water cooling, but that is about it.

I'm pretty used to building my own boats. I don't muck around. It will have some shape to it by tomorrow if the weather holds out. It will take a while to get my engined worked, and all the little goodies that go with it. When I have a design idea in mind, the materials to build, and the days off from work. I can whip out a tub and sponsons in 2 days. That has been the rate, lately.

Just call me the weekend warrior ;D

Hammer

 

[Don Templeton]

#@X%!# - Slow down Hammer I can't keep up! :

 

[Hammerhead]

Wow! I finished a lot today. I got the Tub almost all finished, except the rear sponsons and the lower decking. Using almost exactly the same framing technic as the Hammerhead .12.

If it doesn't rain like the weather forcast says, I will have the Tub done, and perhaps the sponsons.

These are the specs.

Length: 900mm

Beam: 650mm

Tub heigth:48mm

Tub width:87mm

Angle of attack- Front sponsons: 4.3degrees

Angle of attack-Rear sponsons: 2.2degrees

Tank 150cc

Shooting for having the CG at 370mm from sponson tips.

Hammer

 

[Mark]

Hammer,

If you were to build a hydro to take a 16hp engine what total length would you make it and how wide?

 

[Hammerhead]

Answer this question first, Mark. Where in the heck did you find a 16hp engine? I think the most powerful engine I have ever owned is a K90. I haven't seen any specs on it, but I doubt that it has more than 6hp. Probably more like 4.8-5.2.

Are you talking one of those twin Quickdraws? If that is the case, I probably wouldn't build a rigger for it. I would probably make a boat that I could take out fishing. You know, the Suzuki 9hp outboard engine can get me up on water skis!

To answer your question, there is a lot more than just knowing the horsepower of an engine to determine the size of the hull, and the technic I would use to build it. Of course, I would need to know the size of the mount, the weight of the engine, and how big a fuel tank it will need to get enough run to finish a heat, or whatever kind of race your planning enter with that thing.

So, I guess with the info at hand, I have to say, I haven't the faintest idea. ???

Hammer

 

[Anders_Martinelle]

Hey Hammer!!

Look at this: http://rcboat.com/exhaust.htm

And you will see that the K90 is OVER 6,0hp!! even a P67!!.

I think the best tuned 90 or 100 engines are close to 8hp!!

The new Mathe casa testarossa 2003 might be at the 14-16hp mark.

Anders

 

[Hammerhead]

Well, It says the K90 has 7.48 hp. Impressive! I new it had power, but I didn't have the faintest idea that it had that much.

If the configuration of the Mathe casa testarossa is the same as the standard Mathe. I would make the hull, 6" wide, the length 1300-1500mm long. Where I would mark the sponsons would depend on the purpose of the boat.

Hammer

 

[_laxmasta2039]

a twin QD rigger would be something to see, but i would think fiberglass would be the material of choice instead of wood......

hammer,

well now i know nothing huge changes in hull design when it the neighbors get extracted from the course, the only thing thats really different from the common riggers is the size because of the engine size?

Joe

 

[Hammerhead]

Say for example, you have a 29 inch long .21 rigger, and it has a 2hp engine in it. It runs and handles great! So now you want a make a boat like it for a 14-16hp engine that is exactly like it. Do you make the boat 7 to 8 times longer? The answer is, no.

Sure you will be turning a monster prop, but I doubt that the RPM range will be anything compared to a hot .21. Lot of factors. I don't even wanna think about it.

If I had a big engine like that, I would make a Miss Bud 9 feet long with hydraulic steering linkage and I would slap a helmet on my youngest son and scare the crapolla out of him. :

Let's focus on the threads subject now.

%&$&$ going straight. If you know me, you will also know that I'm not into SAW. You know those guys who make fun of the dual purpose yard work and pond toy petrol boats, well I feel kind of like those guys when it comes to SAW. Impress me!! Go 100 miles an hour around an oval! That's exactly what I plan on doing. I'm cocked, and I'm ready. Actually, I'm in a bad mood, because the guy who was going to machine my case, backed out. You know why? Well, there is this guy over here that holds the record for C Hydro. He told that guy what I was planning to do, and they decided, that if that's the case, illiminate the competitor. Well they can go &$&% themselves, cause I'm gonna show up unexpected with my machined cased .48 VX-M and blow his pansy A$$ off the pond.

Those guys should never make me angry > , cause I always win when I am. (please disreguard this paragraph if I lose )

Hah! By the way! Welcome aboard Andy! No hard feelin's okay.

Hammer

 

[MikeP]

Go get em Hammer, I am sure you will find someone to do machine work, if not send it over here.

-MikeP

 

[Hammerhead]

I might just do that! Might see if Dale can do it.

He's purty good at machining.

Sometimes I wonder. I don't want to get down on the Japanese, but ....., that is cheap play. About 10 years ago, the Giants benched an American player, because he was 1 homerun away from breaking the record. I thought that they would grow out of it, because of all the flack they got over that, but last year, they did it again. A guy from the Dominican Republic was 1 homerun off the mark and they walked him everytime he went to bat. Guess if you wanna win, you have to play dirty. I will figure something out.

Hammer

 

[Hammerhead]

Oh! one more thing. If you are wondering why I don't do it myself. Well, I would, if I had the machinery. I suppose I could pick some up that would do just about anything I needed for about 2000 dollars. Come on, now. Which would you rather do? I'll tell you what I would do if I had an extra 2000 bucks laying around. I would build a couple of riggers and pay someone a fraction of that to do my work for me.

Most guys who own machinery like that do it for a living. Might as well support their cause.

Hammer

 

[Hammerhead]

I found a way to do it with out machining the engine case. Guess I won't be able to use that cool looking crankshaft that I had made. Add it to the gallery! I found a guy who will reduce the size of the connecting rod pin. And with his titanium connecting rod, It will become a .47. Good enough. Gonna have to change the name to the "Hammerhead .47 (project stategy)" What's 1/100 of a cubic inch anyway. I can make up for that with merely my good looks! ;D

Hammer

 

[TimD]

Hammer,

I had a case "trenched" for a bigger rod about 12 months ago by a friend. If you can't find someone to do it let me know.

Tim.

 

[Hammerhead]

Thanks Tim. I might take you up on it. I'm gonna try the .47 first, since I already asked the guy to make up a titanium rod for me. If I bust that engine up, and need another one, It will be on it's way.

Hammer

 

[TimD]

Hammer,

That crank looks sweet, it would be a shame not to use it.

Can you tell me a little more about the crank - like is there anything special about it? I have to admit I am asking for selfish reasons - I'm a frustrated Picco 67exr owner who can't shorten the pipe for fear of the crankpin going bang!

Tim.

 

[EatMyShortsRacing]

I am actually interested to find out why go for the .48 to put it against the .67s???

Is this a suggestion that the OS 45 will out perform a MAC 67 for instance?

EMS Racing