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After a few days frantic activity which included building a torsion axle aluminum trailer, I finally found myself following ol nameless across Port A to UT marina. Figuring to stack the odds of a successful launch in our favor we elected to launch at high tide right after dawn. She slid into the water, floated (!). I guess after all this time and effort, and being a naturally worrying sort I had all kinds of possible bad scenarios running through my mind, from the trailer breaking in half and dumping our creation, to launching it and seeing water not seeping but actually spurting through our welds....but she proved me wrong.
Zero leaks. The bilge is powder dry. She's floating about 1.5" above the water line light. Engines cranked and purred like the million dollar babies they are. We fitted, against strong protest from many a prop expert, 14.25 X 17 Stilettos, which appear to be a pretty aggressive prop. But that's what we had available and you gotta start somewhere.
Little playing around with the controls in the marina, she spins in her own length in reverse. Wait for the tankers to clear the channel, head through the cut and we're in the jetties heading for the Lydia Ann channel. Ease her on out, listening for the tortured sounds of tearing metal, putted around per break in sequence for an hour or so. Wind her up a bit and see what she'll do. No lack of holeshot here, she jumps onto plane. Man, this thing is fast, amazingly fast in fact considering the hp and size. We restrain ourselves, mindful of the breakin period, incomplete flotation installed, and total lack of insurance. Hunt some boat wakes, punch em at 90, ahhh yesss. Smooth.
Poke around a bit, got the two hours on, short blast of full throttle, 41.7 mph. But wait a minute, we got magic props or something, cause we're making that speed at 4000 rpm? Run a quick prop calc, tachs are set wrong. I'm assuming that 4K is actually 6000 cause that's about right for the speed and pitch. Here's some numbers for fuel and speed, I'm eliminating the tach readings cause thry're not correct. All speed is GPS, fuel is Navman. Runs were in both directions. Fuel is per engine.
14.4 mph, fuel 1.4
20.5 mph, fuel 1.9
26.8 mph, fuel 3.6
30.8 mph, fuel 5.2
34.7 mph, fuel 8.5
41.7 mph, I was so excited I forgot to record fuel burn.
The ride is superb. It's great to build something that works from the git go! We're pulling her tomorrow to finish out the interior.
So, very few squawks indeed though I do notice one issue. The further the engines are trimmed down, the faster she goes. What is this, I've never run across this characteristic in a boat before? I'm thinking the props are slipping a bit more than they should be which isn't a big problem but I want to be able to hike the bow more which is an issue. I see a couple possible fixes, larger dia four blade props being one, and Permatrims being the other. What do you guys think?
Congrads! That is a real nice ride. You took the road I had thought about taking a year ago but decided against. Please give some more info on her. Designer? Time required? Would you do anything different (I know, to early to tell). Again, CONGRATULATIONS!
That's one nice "Tex-A-Cat"! Forget the Permatrims,It looks as if the engines are mounted a bit high. Another 6" or so lower and that may cure your trim issues and help your already good performance specs.
My 25 custom/Manta cat will go faster as well at lower speeds (less than 23mph)with less trim angle. And yes she is planing. My hulls are very similar looking to yours as far as the running surface goes. Any thing above 25 mph and more trim helps speed her up.
Great looking boat. I will be starting a composite 33' cat in about 2 years when my kids get a little older and easier for mom to handle.
Chuck, Nice job on the cat, forget about the permatrims and four blade props. Get a good pair of trim tabs. Four blades are for front heavy mono's so they can plane faster. You will see if you get used to the trim tabs and trim the motors what you can get out of her.
skypoke - 7/6/2005 11:50 PM
... I want to be able to hike the bow more which is an issue. I see a couple possible fixes, larger dia four blade props being one ...
Interesting. Many people try 4-blades props for the hole shot and hookup/bite in the water, but if you read closely to the specs/claims by the prop maker, 4-blade props also provide extra bow lift.
This prop below is what my buddy with a heavy 22' deep-V CC tried on his 200hp motor while I tried it on my heavy 25' Paaaaaka mod-V hull with a 225hp motor:
This prop (we tried the 14.5"X17p) is a 4-blade SS prop that OMC called the "Renegade Offshore" series, now called by Bombardier as the "Renegade Cyclone". Bombardier describes this propeller as perfect for heavier boats operating in varied and demanding seas. It is designed to provide extra bow lift and maintain a good bite while tossing and turning in nasty water.
Neither one of us lost RPMs switching from the 15"x17p SS premium wheels we were turning, but where he has the deep-V hull, he didn't really notice too much bow lift. He did realize the 100% better hole shot, more prop bite in the water, faster speed & better efficiency @ cruise speeds, while not losing any MPH off the top end. He loved this prop so much I think he put some bad karma onto it for my boat, as the results were totally different (due to hull design).
On my boat ... not that I can compare a beamy mod-V (14 degrees) hull to your cat ... I noticed so much bow lift that I had to deploy my trim tabs much deeper than usual just to see over the bow. This didn't work for me as the tabs start to cause drag when set down to far and it started to kill my fuel efficiency. Yeah, I shot up onto plane allright, but I had to use so much tabs to keep the bow down (or else I can't see over the dash , and I'm not a shorty) that my cruise performance suffered. Max RPMs also stayed the same for me.
Point it ... from this one simple test, I'd sure try premium 4-blade props, as they sure added tremendous bow lift!
[red]GREAT job on your boat - enjoy![/red]
__________________ [red]MISS TEAK[/red], 25' Parker mod-V Sport Cabin "Life's too short to own an ugly boat ..." www.classicparker.com
From yur comments, it sounds like you still have to add foam, some cabin weight and completly fill her up with fuel and water to see how she will run finished out and heavy, but while running light you are getting better than 3 mpg at 30 mph on break in, and that is really great for a 28 footer with a cabin, guessing on the props. I expect that the foam and fuel will lift her bow a bit, so you'll have to see this effect before you start playing with different props. A couple of coolers with beer and ice sitting in front of the engines will probably get you the lift you want and this is standard running gear anyway.
When Roger did the calcs for my CC I asked him to give me 3" of positive lift over level in the bow which he kind of objected too, but from your comments, I am glad I did. And if you are getting these king of speeds on a 28' with 150's, I think that +50 mph is realizable with the same motors on a 24' with no cabin.
I know its early to tell, but do you like the planning sponsons in terms of smoothness too?
Thanks for the attaboys, guys. I'll try to answer some of the comments.
Running/handling characteristics. She throws almost no wake except for the wash from engines and spray exiting tunnel. There is no spray on the engines at all (relief) and we ran her for three hours before getting the first drop of spray on the front glass. Of course the cockpit is dry. Ride is very stable and from our limited testing seems to not even notice small chop. I believe it's planing at around 12 mph or so, maybe a bit slower. Handling in reverse is excellent, but forget sharp turns forward. Throttling up outboard engine makes turn faster.
Operational weight with fuel, pax and ice will be around 7200 lbs.
Speed, accelleration handling are all exceeding expectations at this point but we havent' given her the acid test offshore. As far as the prop issues, and bow lift go, based on Pimpin's comments I'm going to run her a bit more and see if I truly do need more bow lift. I'm pretty sure I can get it with the four blade props, don't mind if I lose a bit of speed as I can't see running that fast offshore anyway. We'll most likely go ahead and add air conditioning and a Honda EU2000 genset and I'm sure weight will creep up so might need the added torque of the 4 blades. Reel rascal's experience with the Renegade props is pretty compelling, might go that way.
There's more pictures of the const process in the album section for those interested. I'll try to get some running shots next week sometime.
All in all, a very satisfying venture. While I got into a new boat with new engines this way for a fraction of what the rig would cost to buy outright, and encourage anyone interested in building to have at it, don't forget....it cost me two years of fishing to do this in my "spare time". It's most definitely time to do some catch up in that dept., we're going to whip a basic interior into her and run her hard.
My apologies, of all the guys to not respond to I pick the one with the most extensive cerebral databse of good deals on boat parts in the world! This is the guy you need to have as a friend if you're boat building.
Nope, the windows don't open in the front. We used a locking gasket and had glass cut and tempered. I was going to use side sliders from your source on the side but am again considering using curtains to allow them to be fully open. If we put AC in we'll have custom sliders made for side openings.
The entire inside of cabin is going to be foam lined with 1 and 2" rigid foam, headliner over that. I really haven't noticed the need for front windows to open and it's plenty hot here in southern hades.
How's your rig coming along? Got those Suzukis hummin yet?
How's your rig coming along? Got those Suzukis hummin yet?
The pace has slowed a little. I worked hard on it for 5week's stright to get it painted. I'm adding thing's daily, but I took a few day's off.
Now I'm working on X brace cabling for the new boat shed in prep for this storm.
The boat's in the big shop. It will not fit in there when the motor bracket goes on.
I would have to have those window's open so you can talk to someone on the bow working the anchor line if nothing else.
Now you could buy a VHF w a hailer feature on it. The speaker will mount on the hardtop. When in the hailer mode you can talk back and forth.
I have a SH Spectrum+ VHF. This thing is neat with the siren feature too.
Look out Jet Ski's.
WOW!!! That is truly awesome. You definitely have a lot of talent & a lot of time. Something to be very very proud of. That has to be one of the nicest looking cats Ive ever seen. Congratulations Keep the pictures coming
Hi Chuck: It's great to see you finally got the - Sorry, I will learn to watch my language - wet. Drop me a line and let me know what your new e-mail address is. The last couple I've sent come back undeliverable.
Alloy cat build update-she's wet! 
