Flathead's Combee TomCat

[Duane Scarborough]

Buster,

You've hit the nail on the head with your 3 reasons.

I see of lot of rodders building up bad Chevy engines, but not so many Ford guys.

Not that they aren't out there, I just don't see as many.

The common bell housing pattern probably does have a lot to do with it.

Thanks,

Duane

[Flathead]

Hi all!

It's been awhile since my last post, so here's what going on. I got the porpoising problem straightened out on the Fatcat. I'm really happy the way it eventually came together. It will run about 26mph WOT and get two people on plane. That's more or less what I wanted all along. My plan then was, if the boat ran well, to rebuild the Factcat properly, without cutting any corners. I'm sticking to that plan.
I've also decided to repower the Fatcat. It's just a bit too slow and has to work just a bit to hard for my tastes. I have recently purchased a 582 rotax snowmobile engine rated at about 65hp. It will be lighter than the VW and produce about 25 more hp. Plus, I got it at a VERY reasonable price. ( got all the extra stuff as well, carbs, guages, exhaust...)
However, I do not plan on tinkering with the power package. I'm going to have an expert tell me which redrive I want (belt or box) the best ratio, and prop combination to use with it. This power plant is very common in the ultralight community, so I have to believe everything has been tried and a proven combination should not be hard to find. I figure the Fatcat can swing a 62inch prop.
I have a great deal of work to do on the boat itself, so any help I can get on this re-power project would be appreciated.

Chuck,
I am hoping you can help me and tried to send you a PM on this topic, but it would not go through...

Happy boating!
Bruce

[buster]

Hey Bruce,

Good to hear from you again. You probably heard my boat is running good now, my top speed is about 25 mph. I been running it on Linwood lake just south of my place. The shoreline is rather shallow for a ways out, a good place to run.

Dave

[Flathead]

The forum has been kind of quiet for a while, so I'll throw this out there. Progress on the Fatcat is continuing as you can see. I've reinforced the bottom and begun painting. I have a rotax 582 (65 hp) for a new powerplant and I'm still in search of a 3:1 belt redrive for it. I thought I found one, but it turned out to be a 2.2:1 ratio. Fortunatly the guy agreed to take it back. I hope to complete painting this weekend and start building my prop cage. The hull, as you can see it weighs 280lbs, so I think it will be right around 300lbs once I finish it up.

BTW, I met Buster face to face a couple of weeks ago for a little horse trading and I'll tell ya he's just as nice in person as online.....Oh yes, and his boat looks just as good close up as it does in his pictures....

Flathead

[Duane Scarborough]

Flathead,

It's good to hear that you're making progress.

I haven't met Buster face-to-face, but have talked with him on the phone a few times. He is a nice guy, I don't care if he is a Yankee.

He told me about some of your horse-trading. I hope that it works out good for ya.

Duane

[Flathead]

Still making progress! Busters emt bending technique worked great! I was impressed how slick it worked. I found another motor, but in good running condition, so I'll be able to save some time and cash....

Currently I'm trying to get the motor mounting plate in just the right spot so I can fab up the supports. All is going well, just need more time.......always, more time.....

Flathead

[buster]

Flathead,

Looks like you have made some good progress. Mine is still about the same as when you saw it. My problem seems to be a lack of ambition now that the weather has turned cold. I just may wait until we get warmer days.

Keep posting the pictures though, It' lookin' good

Dave

[Papee]

Now you have a taste of it. Using the motor in an airboat application is most likely the hardest on the motor, it's not like a stock application or even a dune buggy. You are asking it to pull 90% of the time it is running. These days when I make changes to my 084 boat it may look like I am trying to find more speed but in reality I am looking to make the boat more efficient so the motor does not have to work as hard. Another MPH in top speed gets you a better cruising speed also allowing you to run the boat at a better cruising speed but not as hard on the engine. Unless of course you are gaining speed by increasing engine rpm.

I look for things I can do the the hull or the way the boat is set up for more performance, total weight or weight distribution. The most important thing in building a mini is spending time on your hull making it work as well as possible. This is kinda what I set out to do when choosing to run a direct drive, I was always the one trying to get the most out of as little as possible while keeping the setup reliable.

I was one of the first, if not the first to get a 12 ft jon boat to plane out with a 8hp motor running direct drive with no motor modifications other than removing the governor. I used a very light hull(thin) which lead to other problems on the rocks here but the boat worked very well until the day I sold it. I sold it to a kid who tried to improve it and also added more weight to make it fancy and it went downhill from there.

Not long ago I saw a very nice looking VW boat at the river. The boat was beautiful! The problem was it wouldn't plane out very well if at all. He spent all his time adding fancy seating, a cool control panel that folded up and out of the way when fishing, as well as junction boxes for his wiring. While making a nice build and very nice looking boat, he also added a lot of weight and the weight that was there was not equally distributed. I always use what my daddy taught me, He was a mechanic at Piper Aircraft, KISS... Keep It Simple Stupid! I just always thought he was calling me stupid until I caught on.

Well enough of my ramble, just remember what ever you do... Keep it fun and have fun while you're doing it.

If the wimmins don't find you handsome, at least have them find you handy!

[Duane Scarborough]

Flathead,

That's looking nice.

Honestly, if you'd asked, I'd have probably said "DON'T paint it yellow".

Fortunately, you didn't ask, so I didn't nay say your color choice.

The yellow / black color combo really DOES look nice. I like it.

I especially like the way you're doing the cage. We see so many half circle cages that we start to think of that as the only way to do it.

Your mostly full circle cage looks good. Hmmm... wish I'd thought of that.

Keep up the good work !

Thanks,

Duane

[Flathead]

Papee,

Thanks for the insight and for taking the time to share it. I am a great believer in simplicity. All I really want if for the boat to work well and be able to cruise comfortably with two people and a cooler in it.

Duane,

You can thank Georgiboy for the cage idea. I think it will look cool, whether or not it will be a pancake style or a full enclosure is yet to be determined. As far as the color choice goes, The Combee company logo was a bumble bee driving an airboat. Kind of a tribute I guess. (Besides, I like i too!)

Buster,

How's that new hobby coming along? I think of you every time I look at my dust covered banjo!

Bruce

[Bogger2]

Flathead,
I like what your doing so far. What was it that you used for the bottom?
As far as a reduction I got lucky and My 2.58 gear reduction from my original 503 motor fit on My new 532 Rotax. It pulls quite well with the setup.
best of luck
Bogger

[Duane Scarborough]

Flathead,

It brings to mind a friend's 1970 Dodge Coronet Super Bee.

It's Yellow and Black also.

Hmm... I'm sure you can find those logo decals if you want.

I don't guess I've ever seen a Combee logo, but you probably can chase that down too if you try hard enough. If you can locate a decent photo of one, you can get a sign shop to make up a set of decals fairly cheap. I vote for that.

Thanks,

Duane

[Flathead]

Duane,

Check out the first page of this thread. There's the logo. My daughter is a good artist, I might just ask her to paint it on when the time comes.

Bruce

[Flathead]

Bogger

It's 3/8 thick poly. When I widened the boat, I discovered the old fiberglass had been repaired so many time it was 1/2 inch thick in spots. The stringers wet and rotting too, so I just cut it all out and replaced it with the poly. Looking back on all the trouble I had getting it stiff enough to work, I would have been better off just finding a new hull. Unfortunatly, there are darn few of them here in Minnesota, dont'cha know.

Bruce

[Flathead]

The Fatcat is still moving along. I've got the motor mount mostly fabbed up and I'm currently painting it. Yes, that is snow inside the boat. We had a big storm and the boat was outside. Lots left to do. Time, more time......

Flathead

[buster]

Flathead,

First, I think you made an understatment about the big storm. I believe I heard it was the most snow in one storm of all time. Guess what, winter starts next week

Next, Since your project is lookin so good, I may just wait until it's done, and then steal your ideas. Hope ya don't mind

Dave

[Duane Scarborough]

Flathead,

When I went back to look, I saw the LOGO. Yeah, I'd seen it before, but it just didn't register in my thick skull. You probably will not find it on-line, so your best bet may be to either have your daughter do it (which would be awesome), or get a sign shop to reproduce it.

We've had our share of snow here in N.C. as well. Nothing like what Buster and Papee have seen though. But then, those guys just LOVE snow.

Please keep us informed of your progress.

Thanks,

Duane

[Bogger2]

Hey Flathead, Did you get my reply to you starter PM?
I'm not sure if it went out.
Bogger

[Flathead]

Still making progress on the Fatcat. We are in the middle of the snowmobile season here in MN so progress is slow. I've got the radiator mounted as well as the fuel pump, primer and shut-off. The exhaust is mostly finished. I'm starting to work on the electrical system now. Hopefully, I'd like to be ready to start the motor by the end of the month, but that may be a bit unrealistic. Anyway, here are a few pics....feel free to comment. The forum is a bit slow right now. By the way, I'm using as much of the original snowmobile parts as practical. The exhaust, cooling system parts (minus the radiator) fuel pump, primer and tank have all been adapted to use on the fatcat.

Flathead

[Flathead]

The Fatcat is getting close to getting on the water(finally). I've finished up the prop cage and only need to attach the rudders and cables to make it functional and ready for testing. If all goes well it should be ready in two weeks to get on the water. Then, if all goes well, I can begin buttoning up all the loose ends I've been putting off......

Bruce