Fun with Tunnels

[RonShaw]

After this thread perked my tunnel interest again, here's a rough mock up of my new 7.5 tunnel. The sponsons and center section need to be completed prior to marrying the two together, but it's getting there. I also need to build a radio box and figure out the cowl situation. The hull was designed by my father.

Dean,

That looks great. Two ideas. First, its hard to see how you are supporting the transom but make sure you have solid lateral and horizontal support to withstand a lower "strike" with an object in the water (turtle/debris). Many transoms have been ripped out in this scenario due to the high mod speeds. Second, there are several builders out there that have 40 size cowlings with the nose built-in that could be easily retrofitted for your tunnel to save you some time. The 40/60 Leecraft cowlings that I am having manufactured do not include a nose. Check with Carl Van Houten, Shawn Junker, and Kris Flynn to check their 40 cowling widths/lengths for verification of fit. Keep rolling....

 

[DeanJohnson]

After this thread perked my tunnel interest again, here's a rough mock up of my new 7.5 tunnel. The sponsons and center section need to be completed prior to marrying the two together, but it's getting there. I also need to build a radio box and figure out the cowl situation. The hull was designed by my father.

Dean,

That looks great. Two ideas. First, its hard to see how you are supporting the transom but make sure you have solid lateral and horizontal support to withstand a lower "strike" with an object in the water (turtle/debris). Many transoms have been ripped out in this scenario due to the high mod speeds. Second, there are several builders out there that have 40 size cowlings with the nose built-in that could be easily retrofitted for your tunnel to save you some time. The 40/60 Leecraft cowlings that I am having manufactured do not include a nose. Check with Carl Van Houten, Shawn Junker, and Kris Flynn to check their 40 cowling widths/lengths for verification of fit. Keep rolling....

Thanks Ron. Regarding the transom, there are lateral supports that seat into the tub through to the tub floor and are epoxied in, you're just not able to see them in the pics taken. Thank you for the suggestions for the cowl. My father made cowls that aid with providing down force; the cowl's basically made from 3 flat pieces (2 flat sides and 1 flat top) that ascends in height from the front to rear... I'm likely describing it poorly, but the concept works well. The cowl may not win a beauty contest, but it's definitely functional.

 

[Jarcaines]

After this thread perked my tunnel interest again, here's a rough mock up of my new 7.5 tunnel. The sponsons and center section need to be completed prior to marrying the two together, but it's getting there. I also need to build a radio box and figure out the cowl situation. The hull was designed by my father.

Dean,

That looks great. Two ideas. First, its hard to see how you are supporting the transom but make sure you have solid lateral and horizontal support to withstand a lower "strike" with an object in the water (turtle/debris). Many transoms have been ripped out in this scenario due to the high mod speeds. Second, there are several builders out there that have 40 size cowlings with the nose built-in that could be easily retrofitted for your tunnel to save you some time. The 40/60 Leecraft cowlings that I am having manufactured do not include a nose. Check with Carl Van Houten, Shawn Junker, and Kris Flynn to check their 40 cowling widths/lengths for verification of fit. Keep rolling....

Thanks Ron. Regarding the transom, there are lateral supports that seat into the tub through to the tub floor and are epoxied in, you're just not able to see them in the pics taken. Thank you for the suggestions for the cowl. My father made cowls that aid with providing down force; the cowl's basically made from 3 flat pieces (2 flat sides and 1 flat top) that ascends in height from the front to rear... I'm likely describing it poorly, but the concept works well. The cowl may not win a beauty contest, but it's definitely functional.

Like this?

 

[DeanJohnson]

After this thread perked my tunnel interest again, here's a rough mock up of my new 7.5 tunnel. The sponsons and center section need to be completed prior to marrying the two together, but it's getting there. I also need to build a radio box and figure out the cowl situation. The hull was designed by my father.

Dean,

That looks great. Two ideas. First, its hard to see how you are supporting the transom but make sure you have solid lateral and horizontal support to withstand a lower "strike" with an object in the water (turtle/debris). Many transoms have been ripped out in this scenario due to the high mod speeds. Second, there are several builders out there that have 40 size cowlings with the nose built-in that could be easily retrofitted for your tunnel to save you some time. The 40/60 Leecraft cowlings that I am having manufactured do not include a nose. Check with Carl Van Houten, Shawn Junker, and Kris Flynn to check their 40 cowling widths/lengths for verification of fit. Keep rolling....

Thanks Ron. Regarding the transom, there are lateral supports that seat into the tub through to the tub floor and are epoxied in, you're just not able to see them in the pics taken. Thank you for the suggestions for the cowl. My father made cowls that aid with providing down force; the cowl's basically made from 3 flat pieces (2 flat sides and 1 flat top) that ascends in height from the front to rear... I'm likely describing it poorly, but the concept works well. The cowl may not win a beauty contest, but it's definitely functional.

Like this?

post-6483-0-77352600-1513234661.jpg

24.jpg

Yep, pretty damn close. The vertical sides extend through the flat top by about an 1/8" allowing the top of the cowl to trap air. About midway through the cowl the extended sides blend into the top allowing the air to bleed away as it approaches the rear.

 

[Jarcaines]

Nice!

Those were a couple of my dad's Rod Geraghty tunnels from the early 90's

 

[Alan Elzer]

Here is two 3.5 Tom` Cats before they came out in kits form . Also a 7.5 Tom`s Cat.

RC cars trucks boats 034.JPG

RC cars trucks boats 043.JPG

The old Tom's cat..my first boat too. Ran very well.
Sent from my SM-N920V using Tapatalk

 

[Mark Poole ModVP]

In post #157, the Reno Nats, I'll bet that was some close racing. Probably not real fast but close.

 

[Jarcaines]

In post #157, the Reno Nats, I'll bet that was some close racing. Probably not real fast but close.

I was 7, so I don't remember much, but I remember it being by far the worst Nationals I have ever been to before or since. It was in a dusty dirt parking lot and there were wind/dust storms every afternoon. Some of the tunnel participants went out and bought cookie sheets to cut in half and attach to the front of their boats to plow over the white caps. It was brutal.

Maybe that is the birth of Mod VP...

 

[Ron Olson]

Mike, know anyone with a Nemesis kit un built? I would be keen for one to go with my Villain S1 kit

Kris, check with Walt Radzinski (WaltR) in here. I know that he had a few unbuilt Power Surge Racing kits stashed away but I don't know if he's willing to sell or not.

 

[Grimracer]

I dont.. well except for the ones I have.. Walt would be a good check!

Grim

 

[jamie anderson]

here is my first outboard I raced with and had a lot of fun with it.

I bought it second hand along time ago from the usa , would anyone know what age it would be and who made them.

 

[Grimracer]

I have a new wood kit.. Octura and aprox early to mid 80s..

Grim

 

[Andy Greene]

One of these days I really want to visit that work shop Z

You have a Missle Mist can in there somewhere ? Looking for an empty gal can.

 

[jamie anderson]

I have a new wood kit.. Octura and aprox early to mid 80s..

Grim

thanks for the info grim

 

[the german]

here is my first outboard I raced with and had a lot of fun with it.

I bought it second hand along time ago from the usa , would anyone know what age it would be and who made them.

This was my first tunnel as well back in the 80s.

It is a Toms Cat named after "Mr,Octura" Tom Prezenka (hope the spelling is right).

 

[Grimracer]

Andy.. I dont have an empty can.. That was good old FOX fuels.. lol.. I ran that WAY BACK WHEN!..lol

Grim

 

[Andy Greene]

Talked with Fred/ Phil and a few of the OLD school guys today- they all said hey Grim

 

[Grimracer]

Super dudes.. thanks and back at those guys!

Grim

 

[Greg Johnson]

Haven't been on for awhile and missed this. To Tony and Dean. That boat was my first ever R/C boat. HotShot 45 Dumas kit Jerry Dunlap design. Dan Chabowski and myself had the first two and only two initially in D4. We couldn't race as all the tunnels were 3.5's. I still have and use the Go Pop can. I still have the radio but it's retired. First wheel radio and no servo reverse switches. no rate control only the start and stop positions could be set.

 

[Greg Johnson]

My first tunnel hull boat design. The 7.5 Magnum. That's Dean with me down in St. Louis prepping the boat. Weighed a ton, very fast and handled anything but a wave. Part tunnel and part submarine.