1/10th 8255 SCALE BUILD - U-100 MISS ROCK

Sorry Mike. I don't mean to be disrespectful. Especially with the effort you put into our hobby. Not everyone appreciates it the way I do.

An air dam is a bandaid used to fix a design flaw. This isn't really debatable. Don needs a dam because the boat has a flaw that was making it blow off. The dam was the fix. Design the boats so that the pressure on top is correct and you don't need a dam. It's not simple by any stretch but it IS wing design. Top dim longer than bottom dim across the tub will produce lift. You're using the dam to change the dimension across the bottom. Reducing lift. Works killer on a cat that won't stay put too.

I can accept that it's part of the design. I'm only suggesting the same thing could have been accomplished without it.

I don't think Ty's 8255 has been beat. Usually it requires a crash or some other break down. No 1/4 round.

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Originally Posted by cybercrxt

I saw some questions in here I want to address...Left turning vs Right turning 1/10th hulls...My 1/10th scale kits are offered in both clockwise, and counter clockwise versions, which flip the frames so you can build it in either turning direction you need.

Next, addressing the quarter round on the bottom of the hull. I saw where Terry doesn't feel it really does anything, other than make the bottom look bad, lol. Nothing could be further from the truth. With that being said, I want to discuss a project I did with Don Ferrette years ago, which started all of this quarter round air dam being incorporated into many of my kits. I get a lot of people who feel they know better, and delete the air damn, or publicly say it does nothing. I love ya Terry, but you are wrong if you feel it doesn't work the way I intended it. Don set out several years ago, to break the 1/8th scale hydroplane FE SAW record which at the time, was in the 75mph range if I remember. Well, Don started testing, using the air damn technique, and he found his hull, which ultimately went 100mph with 10s and a 1527 Neu, would blow off in the 80mph range..So he added the air damn very close to the front of the bow block...and the hull stayed on the water and has never blown off during his 100mph runs. Fast forward the following year. Scott Liddycoat wanted to set a new 1/8th scale Nitro record, using basically the same hull as Don used for his FE record...The only difference, he had his quarter round about 4" back from the bow...and as fate would have it...he blew off in the 80mph range...the following trials, he came back, quarter round was moved to the front like Don's...His only hull change..and as you can see in the IMPBA record book, he posted a 93mph record. So Let me tell you, the quarter round works, it may be more subtle on a sport hydro, as I am able to make other aerodynamic features more correct for hi speed running, taking some pressure off the influence the bottom of the hull creates...but in the scale hydro world, you cannot change those curved deck features..The boat has to look scale...the only thing I can do, is mod sponsons, and center section bottoms...Having some features like this are important. Don has also run the 171 extreme 1/8th scale Elam kit in the 75mph range in heat trim, and he swears the quarter round bottom has made a difference. ML Boatworks works with many many top racers in the world, and has had those guys share a lot of secrets for the better of the hobby, and the chose me to do these because I listened. Believe in them, they are not just fancy hype! Sorry to rant, but I see a lot of people tell the mass public the things I do don't really do anything, and they are wrong.


Oh, and it was mentioned that Distance is the only thing that changes airflow speed...That is wrong. Diffusing the air with the air dam changes the time the air travels under the hull. It diffuses, rolls the air flow, slowing down how long it takes for the air to travel under the hull..That changes how long the bottom airflow vs. the top airflow take to travel. If that bottom time is longer than the top..guess what, you have a reverse airplane wing without the simple physics you normally see..You have to think outside the box!!

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I've never used 1/4 round on the bottom, but I've certainly tamed a few boats down with shallow L aluminum or carbon fiber across the tunnel. I'm interested in trying 1/4 round. Is it most effective with the flat facing forward or the round? Love to see a photo. Do you use one deep piece or prefer a few shallower pieces in line? I've noticed that adding things like this also changes how the boat gets on plane from a standstill but they certainly make a difference if a boat is a bit flighty. Thanks for sharing.

Let me start off by apologizing for not posting more on this build. With 3 boats going and everything else taking place this past winter season I just started running out of time.....:frusty:

The build went extremely well. Everything is 1/16 sheeting except for the top sponson sheeting which 1/32. Flotation is just 3/4 pipe wrap foam tube. I modified the front air-damn slightly, but still used 1/4 round and cut the angle down a bit more. I had to cut the sides out on the inner rail a bit up front in order to allow the batteries to fit across the tub. You will find that you will need to have everything up front as far as it will go if you build this hull with the rear wing. On the pre-balancing I found that I may even have to add about 2 oz. up front in order to hit the COG right.

I had read some other posts on OSE and one other that some were using the CPS penetrating epoxy thru Jamestown Dist. Co. Well decided to try this product and see how it worked. The standard mix is 2:1 and I also added one part of Denatured Alcohol. This epoxy went on great. It got two coats. After each coat I just used a white rag cloth and wiped it down lightly to catch the excess. Dried over night. What I was really impressed with was the sanding ability. It had barely any clogging / build up on the sanding block. It just dusted like I was sanding the bare wood. Went through half the sandpaper that I usually go through when using West System.

The finish is standard PPG Automotive paints and clear. Going to hit it one more time with a clear tonight to hit some spots that need attention. I think the biggest pain was getting the stripping put on and in a logical sequence. Anybody that has an easy way they do this, please let me know.....:lol:

The cowling and cockpit are from Mitch Dillard at HSC, along with the stacks and the driver was from Doug at ClassicHydros. A big thanks to both of these folks for all their help. If you would like any info on how I finished these just shoot me an email.

Here are a few pictures of the almost finished boat (1985 KISW). Stacks still need to be added and hardware installed. Have our 1st club race on Sunday, maybe I'll have a chance to test it out.

It turned out great looking! Nice work. Hey, send me a picture of it sitting in the water when you get a chance to launch it. I love those shots. I'll post it on my site. Glad I could be of help. Happy building!

The boat looks fantastic Mike! Very nice as usual!:bowdown:

A superb model Mike.
It looks brilliant.

Hi guys...Thanks very much for all the great comments...:lol:

The boat ran great and looks awesome on the water...
Thinking I would like to build this boat in the 1/8 scale version.

A few photo’s of the boat from its first race day.Attachment 159066Attachment 159067Attachment 159068Attachment 159069

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Originally Posted by Speed810

Thinking I would like to build this boat in the 1/8 scale version.

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Me too Mike. I would do the sausage boat. I just really really struggle to be inspired by 1/8 with there being so few places to race them and all.

Your boat looked great last weekend. It's beautiful guys. Run well too. More in the tank I think.

This hull itself is an easy build. The canopy.....not so much. One of us should have made a mold. Next time I'll glass the surface for less paint chipping. Ty's boat looks like it's been through a meat grinder.

Looks great and has very good ride characteristics!

Maybe I missed it. What is your power setup of choice? Looks nice. I'm still looking for a driver figure.

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Originally Posted by T.S.Davis

Sorry Mike. I don't mean to be disrespectful. Especially with the effort you put into our hobby. Not everyone appreciates it the way I do.

An air dam is a bandaid used to fix a design flaw. This isn't really debatable. Don needs a dam because the boat has a flaw that was making it blow off. The dam was the fix. Design the boats so that the pressure on top is correct and you don't need a dam. It's not simple by any stretch but it IS wing design. Top dim longer than bottom dim across the tub will produce lift. You're using the dam to change the dimension across the bottom. Reducing lift. Works killer on a cat that won't stay put too.

I can accept that it's part of the design. I'm only suggesting the same thing could have been accomplished without it.

I don't think Ty's 8255 has been beat. Usually it requires a crash or some other break down. No 1/4 round.

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I apparently missed this thread earlier but not now. Terry..... think the world of ya man but I gotta disagree with you on this one. Band aid?? Not even close my friend, it's what the correct fix is. Design flaw? Well......... yeah it's called THE BOAT. Since they are scale replicas you can't make top side corrections to alter the air flow of something that is creating lift BY DESIGN. The real ones are trying to create lift. Our issue has become the opposite as even at just 50mph by "scale" sizing it's like trying to run the full size at 400mph. Certain hulls like the 8255 don't trap a lot of air under them compared to some others but the real ones tended to run "wet" and why that design only lasted about 3 1/2 years- 82 to roughly early 86 (not counting the hangers on that were around a couple more years). The "108" style hulls (7207,7474) work great with the air traps cut off immediately aft of the sponsons but the reshaped bottom is best for most others. I say reshaped because it's not an air dam per say but a lowering of the belly to speed up airflow and reduce pressure build up. You saying "Top dim longer than bottom dim across the tub will produce lift" only supports what we do- reshaping the bottom to try to offset the top shape. And I'm sure Ty's boat runs quite well but to use that to discredit what the 1/4 round drop accomplishes across the board is wrong. I've raced 1/8 scales for over 20 years as well as setting nitro and FE scale records and no one has officially gone as fast as I have (Liddycoat came close using what he saw me do) with an 1/8th scale and have shared a lot of what I've found to work on them with Mike for the sake of improving these boats.

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Originally Posted by don ferrette

, it's what the correct fix is..

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Did you read that before you posted it? Haha. If a design is correct why are you fixing it?

A design that uses packed air and/or negative pressure to work requires a delicate balance. If it's off you have to "fix" it. That's all I'm saying. Some of the designs we're emulating weren't very good in full scale.........so.......we....um......have ta........do something........what was it?.........slipping my mind. What were we talking about again?

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Originally Posted by Navherc130

Maybe I missed it. What is your power setup of choice? Looks nice. I'm still looking for a driver figure.

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Almost all of the guys from our club are running the Proboat 1500kv motor. 4s lipo around 6k. As little 120 amp esc works. I like the Raider150.

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Originally Posted by T.S.Davis

Did you read that before you posted it? Haha. If a design is correct why are you fixing it?

A design that uses packed air and/or negative pressure to work requires a delicate balance. If it's off you have to "fix" it. That's all I'm saying. Some of the designs we're emulating weren't very good in full scale.........so.......we....um......have ta........do something........what was it?.........slipping my mind. What were we talking about again?

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LOL!! The design isn't correct but we can't change the top shape because...... so we change the bottom. All good my brutha!