JD New 7.5 WOF Tunnel

[Jerry Dunlap]

Just returned from testing my new WOF 7.5. The boat is 34.5" in length, with a 7" tunnel. The engine is a Nelson 45 w/Silver Bullit 7.5 Pipe. Prop was an Octura X447. 55% nitro fuel.

The sponsons and center section are different from the 7.5s I have been running. The sponson flat ride surface is longer by 1"and the back of the sponson blends into the center section at the transom.

The center section tunnel floor is completely flat. This makes it much easier to build the center section because you glue all the parts directly onto the tunnel floor sheeting which is clamped to a flat surface. The top of the center section is also shaped differently. It features a long flat run from the front and then breaks downward. The idea with the center section is to reduce lift and move the lift towards the back.

As Terry Keely says, "If you keep doing the same thing you're going to get the same results(or something like that).

I experienced some good news, some bad news, and some good news.

Good News #1 is the boat the boat launched great and ran flat and stable. Cornering was very nice. I had set the mixture on the rich side to avoid having to row after the boat on it's initial run. There was plenty left in that Nelson.

The Bad News is after about 4 minutes of running the steering started going away.

Good News #2 is I immediately brought the boat back to the beach. I had installed a 5 cell pack I'd recently obtained and had done a range check before running. The pack had accepted a partial charge and then "pooped out." Got lucky on that first run. That pack is now in my battery recyle box.

This first photo shows the boat w/o the cowling.

I'll post a few more.

JD

This frontal shot shows the way the center section runs flat and then breaks. The center section is 25" long and the front of the center section runs 16 1/2" before it breaks downward.

JD

Well, I see the second reply was posted on the initial post and the photos are reversed. Here's a photo of the boat with cowling. I added wood to the Dumas 7.5 Hotshot ABS cowling to raise the back of the cowl. Hard to say where it might end up when I add the attachment.

I also incorporated a feature from the Lynx tunnel floor. Hell, I ain't proud there's no question the Lynx works!! There's a center pad running the length of the boat and that pad drops 1/8" the last 1/2 of the tunnel floor to create sorta a downward deflection. I'll post a photo of that later.

JD

 

[Slideblues]

Hey JD,

Nice!!! I was waiting for these, wondering what ya been up to, Center is different "the break"

Neat ideas

Gener B)

 

[waterbug]

JD

Will we see this one in production to ?? Made my WOF 34 plans OBSOLETE !!!

Butch

 

[[email protected]]

Very impressive workmanship and glad to hear it can handle such a strong power house of a motor.

 

[MarkScott]

Nice boat there JD.. Just when I get done building two 34" and ya come out with something new... SWEET....

 

[Jerry Wyss]

Nice work Jerry!,, I'm Not gonna try and build one :lol: :lol: ,,,not right away anyhow.

Those Nelson Motors Rock,,,I hear you can still get those, yeah? :huh:

Look's like the 7/5's are comin' back Big,,that's good news,, now if AB can just get

those Mac 7/5 OB's done h34r:

 

[Jerry Dunlap]

re: I hear you can get those?

Gary Preusse is the Nelson OB distributor. Lohring Miller mentioned he was considering selling his Nelson 45.

Here's a photo of the tunnel floor pad.

I'm hoping to get in some serious testing tomorrow. Maybe the rain will hold off till I "get 'er done."

JD

 

[Slideblues]

Ahhh Haaa...Now that last pic is interesting

Gene B)

 

[Ed.R]

Awesome job JD,thats sweet. Were can you pick up a set of plans for your other boats?

Thanks for the pixs. Ed.R

 

[Jerry Dunlap]

Re: pick up plans

Plans for the JD WOF 28/30 are available from RC Boat Modeler.

I'm planning to do a set of plans for the new WOF 7.5. It is easier to build than the 7.5 boat I currently have plans for.

JD

 

[Ed.R]

JD Would a new builder be able to handle ?

 

[Jerry Dunlap]

Hi Ed,

I would hesitate recommending building a WOF hull if you have not done much in the way of "built up" construction. Several of the guys on IW have built my WOF designs. They might be able to provide a better answer to your question.

Before I started doing wood-over-foam, I had built framework boats for 25 years. I've been doing WOF for something like 15 years. I have ended up providing extensive assistance(dang near built the entire boat) for several fellows in my area who started a WOF tunnel with limited building experience and not much in the way of tools.

I really like to build tunnel boats using WOF construction. The boat I ran today was started 10 days ago.

JD

 

[MarkScott]

Ed,

I would add that is simple to build a WOF if you are handy with tools. The main one you'll need is a band saw. In my collection are 29", 34" and 47" WOF Solutions from JD's plans.. Also built a couple of WOF spoons for a couple of people..

Any questions, you can shoot them my way...

 

[Ed.R]

Thanks for the info from both of you .I have 1 boat and it"s a Lap Cat II, I would love to try and build a boat. I'am sure I'll be asking more questions in the future about this very supject.

Thanks again Ed.R

 

[noodles]

I'm also intrested in plans. When will thay be available?

[email protected]

 

[Jerry Dunlap]

re: plans

I have plans for a 34WOF that I've been running before I did this new boat.

Plans for the new boat will not be available for at least a couple of months.

JD

 

[Jerry Dunlap]

Had an opportunity to make some runs with the new WOF 34 today. Weather conditions were pretty miserable - rain and wind.

I still have some tuning to do with prop height/prop thrust and maybe some additonal weight on the sponson tips, but I did get the Nelson to come "on pipe." Running with the wind, this is the fastest I've ever seen one of my boats go with a mod 7.5. Blew it off twice running into the wind(but it was gusting to 25 mph).

The prop that worked best today was a X447. The c/l of the prop is 3/8" above the sponsons. The thrust angle was basically neutral and I think it needs just a bit of down thrust. We have a club race on Sunday that will provide me with an opportunity to race the boat. Unless the wind subsides, I might be trolling rather than racing.

JD

 

[Joe Reese]

WOW. I had the hardest time building sponsons for mine, but patiance payed off. Not, I had the boat built in four weeks Take a look if my attachments if they would attatch.

 

[Ed.R]

JD were can we get plans for the 34 WOF , I went to r/c boat modeler and found the 2 for a 3.5 not the 34.Can you get the plans for the 3.5 and just stretch them to 34?

Ed.R

 

[Jerry Dunlap]

JD were can we get plans for the 34 WOF , I went to r/c boat modeler and found the 2 for a 3.5 not the 34.Can you get the plans for the 3.5 and just stretch them to 34?

Ed.R

I sell plans to the WOF 34. Here's a photo of the boat Joe Reese built from the plans.

JD