I have a set of plans that I think I can be happy with, before I build the mold I was wondering what you guys like in a hull shape? 8) I have seen stuff that is straight from front to back, narrower at back, narrower at back and front with fat in the middle, narrow at the front, different levels of slope on the sides from slab 90 degrees to whatever. What do you guys think works before I build this mold? :wink:
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HULL SHAPES
- Thread starter COLD
- Start date
A
Anonymous
Guest
Wider at the back seems to handle very well from the boats I have been on.
A friends old Charlie Jones style round sided hull rode like a Cadillac, and it tapered slightly to the front.
Another friend's Laser tapers slightly and then kicks out rather sharply at the back (curved outward) and it also handles great.
My Kennedy copy does the same thing and I'm hoping it will ride as good s my friend's Laser.
A hull that curves back in at the back would probably be faster and use less fuel, but it may not handle as well, any thoughts on this from others?
A friends old Charlie Jones style round sided hull rode like a Cadillac, and it tapered slightly to the front.
Another friend's Laser tapers slightly and then kicks out rather sharply at the back (curved outward) and it also handles great.
My Kennedy copy does the same thing and I'm hoping it will ride as good s my friend's Laser.
A hull that curves back in at the back would probably be faster and use less fuel, but it may not handle as well, any thoughts on this from others?
For a glass hull, Im very fond of the Panther glass boat. I like the narrow nose and the hard chins. I like a higher side and transom though.
Transom splash pans are mostly for show, they don't do much. I like the ransom itself to lay back a few inches so its not vertical. Makes the boat easier to get out of the mould as well. Another note here is be careful of anything that rolls back into the boat like a rolled back bow. It adds nothing in functionality but means the boat cant come srait up out of the mould.
If your building from scratch, I would build in the bottom countours so you dont have to run jacks to make it perform.
If your a frogger, youll appreciate the narrow nose if your a camper and rider the wide nose will probably suit you better.
It's for you so you have to decide what YOU want the boat to do.
Keep an eye on rigidity. A good glass boat is flexable as a trashbag, not lliterally but it needs to flex in every direction.
If your really going to tackle this job yourself, PM me and I'll give ya a tip on your mould (whatever design you choose) that nobody else uses and will sooner or later save your bacon........grinn
Those are my likes, other folks will obviously differ for their own reasons.
Scotty
Transom splash pans are mostly for show, they don't do much. I like the ransom itself to lay back a few inches so its not vertical. Makes the boat easier to get out of the mould as well. Another note here is be careful of anything that rolls back into the boat like a rolled back bow. It adds nothing in functionality but means the boat cant come srait up out of the mould.
If your building from scratch, I would build in the bottom countours so you dont have to run jacks to make it perform.
If your a frogger, youll appreciate the narrow nose if your a camper and rider the wide nose will probably suit you better.
It's for you so you have to decide what YOU want the boat to do.
Keep an eye on rigidity. A good glass boat is flexable as a trashbag, not lliterally but it needs to flex in every direction.
If your really going to tackle this job yourself, PM me and I'll give ya a tip on your mould (whatever design you choose) that nobody else uses and will sooner or later save your bacon........grinn
Those are my likes, other folks will obviously differ for their own reasons.
Scotty
A
Anonymous
Guest
What does a slight tunnel hull do for an air boat. My boat has one about 2" deep 3' long and 2' or so wide. I would think this makes it a better water riding boat?
Ted, does it look like this one? http://www.bateau.com/studyplans/XF20_study.htm
A
Anonymous
Guest
No appears to be a factory mold. When I put the poly on I could see the fiber pattern. It not a large or long tunnel
A
Anonymous
Guest
Any other comments for Cold?
I'd like to see some more info about hull shapes
I'd like to see some more info about hull shapes
A
Anonymous
Guest
Wider aft is better because of the nature of these boats. Because they have flat bottoms they get no directional stability going forward if they have any inwash toward the rear when in motion.
Simply stated, if an airboat gets narrower toward the transom from the widest point along it's sheer line, then you would have to drive it constantly ..... you could never just relax and let it run. A narrower transom would change the rotational center of the hull big time.
More important, maybe, is that we load our boats heavier toward the transom ..... engines, radiators, gearboxes and belt drives, POWERGLIDE TRANSMISSIONS (Cold!!) than most any other watercraft, so we need the displacement (bouyancy) of the wider transom.
JMO.
BF
Simply stated, if an airboat gets narrower toward the transom from the widest point along it's sheer line, then you would have to drive it constantly ..... you could never just relax and let it run. A narrower transom would change the rotational center of the hull big time.
More important, maybe, is that we load our boats heavier toward the transom ..... engines, radiators, gearboxes and belt drives, POWERGLIDE TRANSMISSIONS (Cold!!) than most any other watercraft, so we need the displacement (bouyancy) of the wider transom.
JMO.
BF
marshmaster pat
Well-known member
Cold - IMO - One of the nicest things about a fiberglass hull (or the ones I have been in) is that the the chimes tend to go from the sides to the bottom in a curve. It is also something I like about riveted hulls. Those rounded corners is something that allows the boat to spin in the grass much easier and increases handling capabilities.
Of course I would believe that it would increase the complexity of building the hull.
Red - you asked for it.
Of course I would believe that it would increase the complexity of building the hull.
Red - you asked for it.
http://www.bateau.com/studyplans/XF20_study.htm
These are pretty much the plans I am using to build my mold, yeah I know. Pretty big! :wink: At the back you will notice it has a little tunnel that I won't be adding, They called it a pocket drive and the U.S. Navy first used them to allow shallow draft operation with a water prop. On an airboat I think it will just increase draft. Scotty gave me some real good ideas that I will incorperate also and they don't show near enough stringers either. I would like to incorperate a certain amount of deckover, especially at the back. I kind of like how this one is done but would need to figure out how to not fill up the enging hole! http://www.southernairboat.com/photopost/showphoto.php/photo/3542/what/allfields/name/airboat4fun Any good ideas?
These are pretty much the plans I am using to build my mold, yeah I know. Pretty big! :wink: At the back you will notice it has a little tunnel that I won't be adding, They called it a pocket drive and the U.S. Navy first used them to allow shallow draft operation with a water prop. On an airboat I think it will just increase draft. Scotty gave me some real good ideas that I will incorperate also and they don't show near enough stringers either. I would like to incorperate a certain amount of deckover, especially at the back. I kind of like how this one is done but would need to figure out how to not fill up the enging hole! http://www.southernairboat.com/photopost/showphoto.php/photo/3542/what/allfields/name/airboat4fun Any good ideas?
Ron Miller
Well-known member
cold-eh' are you going to run this fiberglass hull in the winter in ice and snow???? Or will this be a summer boat?? I have found that a hull for winter will run fine in the summer but one designed for the summer dose not work as well in the ice and snow.
Ron, Is your concern with the fiberglass or design? As far as material is concerned, it works for these guys! 8) http://www.airboats.ca/images/coolboatheadon.jpg
If it's design, please do expound! :wink:
BF, I'll add! :lol: the powerglide with the shortened tail shaft will move the engine about 16' forward of a belt or gear and about 24" forward of a DD's location. That's getting real close to the 8' wide section of the hull. I will take Scotty's advice and put some shape in the bottom. It won't be completely flat. I will have to do a little more deep water than you guys because we don't have a whole ton of swamp up here, (with climate change it is happening though).,so the narrower back should provide a little less drag at speed, couple of seats above the engine actually! 8)
If it's design, please do expound! :wink:
BF, I'll add! :lol: the powerglide with the shortened tail shaft will move the engine about 16' forward of a belt or gear and about 24" forward of a DD's location. That's getting real close to the 8' wide section of the hull. I will take Scotty's advice and put some shape in the bottom. It won't be completely flat. I will have to do a little more deep water than you guys because we don't have a whole ton of swamp up here, (with climate change it is happening though).,so the narrower back should provide a little less drag at speed, couple of seats above the engine actually! 8)
Hey! Cracker got back to me about his buddy that runs the TH350, :wink:
Posted: Wed Feb 15, 2006 7:28 am Post subject:
Heres Crackers Automatic Transmission Airboat Drive. WOW !
http://www.ursinecom.com/gallery/view_p ... on_Cracker
http://www.ursinecom.com/gallery/view_p ... =Cracker_2
Scotty
Subject: Re: buddy with automatic transmission
Hey,
Yes he's been running it for awhile now and he's had a few problem at first with the transmission, but since he got a race transmission hes had no more problems with it at all. He built a shaft and used a pillow block bearing for the tailshaft.
Cracker
Posted: Wed Feb 15, 2006 7:28 am Post subject:
Heres Crackers Automatic Transmission Airboat Drive. WOW !
http://www.ursinecom.com/gallery/view_p ... on_Cracker
http://www.ursinecom.com/gallery/view_p ... =Cracker_2
Scotty
Subject: Re: buddy with automatic transmission
Hey,
Yes he's been running it for awhile now and he's had a few problem at first with the transmission, but since he got a race transmission hes had no more problems with it at all. He built a shaft and used a pillow block bearing for the tailshaft.
Cracker
Ron Miller
Well-known member
colder-eh That is a sharp looking boat and I will bet they put extra stringers on the sides along with thicker glass. As the crushing effect from the ice on the sides of the hull is enormous ... If I was to try a hull like that I would put 3/8 polymer on the bottom and up the sides and all the way to the bow. Personally fiberglass scares me because when pushed to its maximum it brakes Ware Aluminum will bend before it rips. I'm not trying to talk you out of fiberglass I'm just giving you my honest opinion for what it is worth after ?? 10 years of running in the ice. If you want more input on this try the Alaska Gold web
http://bb.bbboy.net/alaskagoldforum
I am sure they have had more experance with the two types of hulls up their than i have.
http://bb.bbboy.net/alaskagoldforum
I am sure they have had more experance with the two types of hulls up their than i have.
Yeah Ron, I am sure they built the Cr?? out of that boat. I can't find it on their site http://www.airboats.ca , however they mailed me some information and I could be dreaming or going crazy (some people would agree with that one), but I thought the 18' was something like 3000 lbs. I would kind of like to stay out of break up conditions, I only have two exposure suits but the water in front of my house quite often stays open because of a power plant up river and the fire department looks like they have been having a blast with thier boat. Just nice tracks to the waters edge and then more tracks on the other side of the river. I have been in the middle of a lake with a fiberglass canoe during spring breakup when the wind came up, It was exciting but dont try this at home kids! 8)
fatboy0054
Well-known member
THAT S JUST A VERSION OF A PRETTY MULLET BOAT !