'68 Ed Karelsen Inboard Hydro

[jetpack]

I'm looking for more info or pics for this hull to help with an R/C boat project.

The only info I have found is at "The Vintage Hydroplanes" website.

http://www.vintagehydroplanes.com/index.html


Any help appreciated, thanks.

[Jeff Akers]

"Dumas" model boats had a kit that looked almost exactly like that called the "Dragonfly". It could be done as an inboard or an outboard. I built a .21 version of it many years ago (actually I modified the kit quite a bit for my particular use) I think it came in a .40-.60 size also...Heck I may still have the original plans for it stashed someplace

Fun to build and run

EDIT: I just noticed you have the plan sheet already
What other info are you in need of..?

[jetpack]

Hi Jeff,

Thanks for writing. I'm basically going to try and get into the 1/8th scale class with this hull. It would be great to have more info than what is on the vintage hydro site. I'll be needing to make the cowl and dummy engine, and generally would just like more pics.

The problem I might face with this attempt is the hull length meets requirements, but it is not an unlimited hull, meaning it wont match the scale of the 1/8th hydros even though the length is within spec.

The only other class I could race this in, it would not be anywhere competitive due to it being up against outrigger hydros.

[Slowboat510]

Hello Jetpack,

About the Karelsen Inboard hydro vs the Drag-N-Fly design, I beleive the Karelsen was a transom rider while the Drag-N-Fly is a prop rider. Based on the engine location on the Hilton Hyperlube hull being way aft, it leads me to believe that this was a transom rider just as most of today's outboad hydros are. I believe Ed just used his outboard hydro configuration, but just scaled it up for an inboard application.

Regarding which class you can compete in for R/C racing, this hull will not be legal for 1/8 scale however you can run in the "Sport Hydro" classes. Check the NAMBA or IMPBA rules for the sport hydro classes. Generally speaking, the sport hydro classes are full bodied hydros with a scale driver or enclosed cockpit, enclosed engine and tuned pipe and a scale like appearance with racing numbers. With this class you don't have to compete against outriggers.

As for the Dumas plans, many of us have built a Drag-N-Fly kit. They blow over very easily. Just like Jeff moidified his kit, so did I and almost every other one that I've seen. If you want to stay with the basic design and keep it as a prop rider, I would recommend at least eliminating as much air trap as possible. Try to spill any air under the hull that you can. I would also suggest rear shoes, but if you race Sport Hydro those are not permitted.

Good luck with your project.
510R
Fast Boats Built Slow

[jetpack]

Thanks everyone for your help! I found a great source here!

[DeanFHobart]

Karelsen Inboard Hydro

To Jetpack et all,

I just talked to Ed Karelsen about this boat. It was actually built in 1962. The first Inboard Ed ever built. It is a larger version of his "F" Hydro.

I saw this boat run for the first time out of the box at the Spring race at Lake Sammamish in 1962.

Jim Benson owned this boat for some time. It is currently in Olympia, WA.

[jetpack]

Hi Dean, great to hear the report!

Kneelers have always been my favorite, and remember watching the F class as a kid. Super scarey when your used to being around A & B stock hydro.

I think how I will go about the build is to try and incorporate seperate air traps so I can play around with the lift, and make a couple different sets of sizes. I might even try making aluminum skirts that can be adjusted somehow. Any ideas on this are welcome if there's any out there that want to chime in...

Instead of adding shoes in back maybe just go with spray rail strakes on the non-trip chines in back???

I have NO clue how fast the engine is going to be with this, I've never run it, but its an old school Webra .61 marine if anyones familiar with it and will be set up for low nitro with a tuned pipe. Its the ringed version with very low run time which I've bought used and reworked.

[boatguy]

Vintage Pics

GREAT VINTAGE PICS! Loved your two boat trailer with the "bread box" on the back. I currently have a trailer the same done up cica the 60s. Those were the days--short sleeve T shirts and Kapock life jackets--some safety! Good luck with your new project--I raced fast electric here in Toronto--Rigger and two round nose hydros in LSH class. Am now back in vintage hydros. Cheers Bill.

[jetpack]

Hiya Bill,

Thanks to you writing me! The pictures and stories you sent me were great! I would like to see your rig sometime, try and post it when you can. I love old school vintage hydros. Sid Crafts, Hedlunds, DeSilvas, all of them.

I threw in the pic that your talking about for others to see. It is of my brother Herb on his way out to the Stock Nationals in Washington state, somewhere around the later '60's if I can remember right. He built the trailer himself, all steel with swing out motor stands. He used to do quite a bit of testing with some of the greats of the time such as Ron Hedlund (hulls) and Tom Moulder (hot rod motors). I was just a squirt at the time, but still remember being brought race to race and hanging out in our boat shop whenever the lights were on. I felt pretty lucky to be around the racing, and made for some great summer vacations.

I'll be in touch with Ed soon, as I get a list of questions going for over the phone. It will be great to speak with him!

I have all my motor work done now, and working on the running gear such as the strut and rudder parts, and then this winter if all goes well on the home front I'll be able to set up a workbench and start cutting out the hulls.

Dumas who makes this kit has three different sizes, ranging from 28", then 36" and finally a 44" hull. I will be making all three at the same time and should make a nice matched family of boats. It is just a matter of getting the hardware ready such as the engine plates ect, and a little bit of planning to make a common radio box with the servos interchangable between hulls. The kits were designed for Dumas by a fellow named Frank Ward who had set records with them when he designed them.

The Dumas kits are built quite heavy, so I'll be just using them as templates using my own wood and veneers. I also put in a few pics of one that I've caught built up on eBay to give everyone somewhat of an idea of what they look like built. Looks like he built this one for an outboard. Mine will be all cabover inboards.

Hope everyone enjoys them. I know my topic is a little bit off the path here but everyone has been a great help!

[Smitty]

I don't know how I ended up here because I was looking for something else entirely (scratches head) . . . .

Dean, you or Ed or both are mis-remembering the year. The Hilton Hyperlube 150 hydro, with a Chevy 2 four-banger running through a V-drive, came out in 1967. I think 1962 might have been when Ed built a DOH cabover for Charlie Dockhorn that looked remarkably like the later 150 inboard.

Ed built a new U-boat for Bardahl that year, of an improved but conventional design, remarking to some of us that if the Unlimited guys were willing to take a chance, he could build them an outboard-style boat like that 150 and have them going "a thousand miles an hour!" (he was exagerating for effect). But the Unlimited people were too spooked by the fatal nose-dive of Ron Jones' Bardahl cabover, and remained so for several years.

Despite having a mediocre engine compared to some other 150s, the Hyperlube boat and Jim Benson (who drove it on his knees using a hand-throttle, outboard-fashion, saving the weight of a seat) were National point champions in 1968, I believe. Dean will recall how this boat took the big corner at Greenlake, and any corner anywhere, as if it were on rails, compared to the hilarious monkey-motion of the conventional inboards as they made their slow and laborious way around the turns. Seattle Outboard guys used to go to the Greenlake inboard race (outboards ran on Saturday and inboards on Sunday) and marvel at how badly most of the inboards cornered.

Karelsen said if anybody ordered another boat like the Hyperlube, he could make it considerably lighter than the first one, but I don't think anyone did. Ed built more "outboard-style" inboard hulls, but for a while they were all direct-drive, front-engine boats, with the driver sitting way back almost on the transom. He might have built one 225 hydro very similar to the Hyperlube, but I forget.

I have a few old clippings with photos and one interview by a Seattle sportswriter of Karelsen talking about the new Hyperlube and Bardahl boats. I haven't learned how to post such stuff to the internet yet, but I'd be happy to photocopy and mail it to anybody who's going to build a model of this boat. Send me a PM if you want it.