Here’s what my “thunderboat” looks like now

[Bob English]

Here is a idea for more air flow. I have done this on a few of my sport hydro's. Get these vents that you can find in all shapes and sizes and install them in the hull or cowling. The guys that fly big r.c. airplanes use them a lot. That is where I get mine from. Just look a airplane parts suppliers for them. They do what they are designed to do. Get the air flowing through the hull. But one of the things I also like about them is they let the water out of a hull sitting dead in the water. You know what it is like, you stuff the boat of kill the engine and it sits out there in the water until you can get out there and pick it up in the retrieve boat. You go to pick up your boat and it is full of water and weighs 25 or more pounds. This way when I pick mine up the water flows out the vent pretty fast and not in the hull when you are dealing with a dead in the water boat.

 

[Rich Jones]

Hey osracer
I looked at the insane setup, and I see what you are talking about. The one thing that I notice is that there are no holes in the rear of the boat to setup a flow of air through the hull for cooling. So the air goes in those big gaps in the front, but it can’t escape out the back. One of the things that has me hesitating to cut out my instrument panel is the thought that I may set up a poor air flow……air comes in the front of the cowling, and then exits out of the instrument panel, and short circuits the tuned pipe, which I would think generates the most amount of heat in the hull. What do you think?

Here’s what I did to cover up the holes. I think they look cool. They come in your basic aluminum color but I painted these with flat black auto primer. I got them from Esprit Model. They specialize in RC sailplanes. They are on the web. You have to get the heat generated by the tuned pipe out of the engine compartment. I also have an opening below the instrument panel in the cockpit which allows heat to escape. For air in the front, one of the things you could do is open up that spark plug hole some. That’ll let some air in. Then a couple of holes in the front of the cowl or cowl deck should do the trick.

 

[Ray Sametz]

 

[osracer]

View attachment 330013

 

[osracer]

I’ve had five Zipp TB’. I made many changes and they kept getting faster and faster. After the first one I never put any vents or slots in the rear deck. I did however copy the Insane with the slots on the sides. Heat was never an issue with this set up.

 

[Jeffrey Hammond]

Osracer
You don’t happen to have a picture of one of your boats with the insane cut outs in it, do you? I’d love to see how you did that.

 

[osracer]

Osracer
You don’t happen to have a picture of one of your boats with the insane cut outs in it, do you? I’d love to see how you did that.

I do, but I don’t know how to post pictures here.

 

[osracer]

I do, but I don’t know how to post pictures here.

Ha! I did it.

 

[Jeffrey Hammond]

You have been a member here for 23 years and didn’t know how to post a picture? Looks like you had a great success! We all learn everyday!

 

[Jeffrey Hammond]

I like this insane cooling treatment. I could cut a bunch of slits in the front and back of the cowling, and make a bunch of air scoops, etc, and it would take me lots of time and add weight to my boat ( although probably insignificant). But the thought of making some cowling cut outs, and leaving it at that has a certain attraction for me. I do want to put faux exhaust pipes coming out of the cowling, but I think I can get those installed and still get the big “insane” cut outs done. May even reroute my water exit lines and put them on the vertical surface between the deck boards and the sponson decks. More work today…….light sanding on sone filled spots.

 

[Jeffrey Hammond]

Started doing some pencil drawings on the cowling for the cutouts that are coming. Think I may put a deflector around the plug opening. The third picture shows the start of exhaust tubes that I want to put in the side of the cowling. The tongue depressors are simply spacers and the silicone tubes will be cut off. I haven’t decided whether to have them just be straight, or show the angle somehow.

 

[osracer]

Started doing some pencil drawings on the cowling for the cutouts that are coming. Think I may put a deflector around the plug opening. The third picture shows the start of exhaust tubes that I want to put in the side of the cowling. The tongue depressors are simply spacers and the silicone tubes will be cut off. I haven’t decided whether to have them just be straight, or show the angle somehow.

No need for a deflector at the engine opening but I would put something where you carb is.

 

[Jeffrey Hammond]

Ok, here’s an update on cowl progress……I want to put some faux engine exhaust pipes coming out of the engine area. I have one side done. I still need to paint the wood support flat black. Then in order to get some additional cooling air inside, I need to carve away some of the support. I also chopped off some of my driver so he sits down further in the boat. He looks much better.

 

[Jeffrey Hammond]

Just got the other side cut out and positioned, so both are ready for painting. Still need a helmet and some kind of life preserver for my driver.

 

[Jeffrey Hammond]

Today I epoxied the top deck, sponson tops, the nose center piece, and the exhaust pipe holders. When I do a large epoxy job, I normally don’t do anything else afterwards, so I don’t get the shop dusty, etc. It only took about an hour, and I was done. Now I’ll wait til tomorrow. Think I came up with a way to attach my driver, and I need to paint the exhaust formers flat black. Then coat number 2 of deck epoxy.

 

[Roxyflash]

On the vents I have cut a three side square push the skin inwards and glued wedges on the inside here’s a picture

 

[Jeffrey Hammond]

Hey Roxy
Do those vents work? They look very nice.
I worked on the second coat of epoxy on the decks today. My wife used her vinyl machine to cut out some instrument circles, and I applied them to the magnets on my dashboard and I think they came out pretty nice! Whadda ya think?

 

[Roxyflash]

Yes they work nice thing is you don’t have to buy anything.When I cut it I use a utility knife with new blade put a piece of wood under the cut I used a block under the skin.Take your time I make several cuts the first one is the most important as the blade will follow on the second and third cut.Mark it out with a pencil after you push the skin tru you can sand the cut the wedge will glue to the under side of the skin and the piece that pushed tru will get glued to the edge.As the air gets pushed tru the hull it acts like a wing and the flow pushes out.

 

[Jeffrey Hammond]

I got a small delivery in the mail today! A new prop, from Bob English! And it is truly beautiful! Check it out!

 

[Jeffrey Hammond]

All
My driver has a life preserver! I guess he won’t drown if I flip Miss Charlevoix, U-45. Also, my cowl cooling cutouts are done, and I painted the exhaust pipe supports flat black. They are ready to be glued to the cowling, but not until I figure out the paint scheme for the boat. Looks like thos long cowling support pieces aren’t doing much supporting, so I’ll probably whack them.