tnltyme

Thanks JW,  I'm forwarding the pics to Dad as I receive them..

JWMods

I wonder what the width of this mount would measure without the round aluminum spacers next to the rubber ISO's ?? Thats what this game is all about if your going to customize an existing mount. The width of the K&B's butt and add in the two sides until you get to 4 3/4's, and the Game is on Baby!,, ok, dude

skyray35

My Feedback: (3)

Nobody has mentioned so far the fact you may be running the engine too LEAN! quite commom for a newbie .I did the same thing when I tried to run my first rigger! Most are tuning on shore to what sounds correct.Like to run me nuts couldn't figure out why the engine keep stalling on launch!! Until a experienced boater that ran riggers recognized the problem right off. You must set the needle to a "sloppy" rich setting to the point it will almost flame out on a throttle blip!I had no idea that was the problem because it is a different story once it is in the water and a load placed on the prop!it will start to lean out on its own and you must start at a rich setting and work up from there. Good sharpe prop and 25% fuel and up! should bring it "on step".My 2 cents worth..........( a already lean setting on shore will overlean in water and stall it instantly)

advanced builder

JW I keep some of the same aluminum stock . You can get small cut's of aluminum stock on e-bay http://stores.ebay.com/8020-Inc-Garage-Sale
or here is one http://www.speedymetals.com/default....FUHF3AodyXb8Vg

tnltyme

We're only running it lean enough to keep it running to launch it. My dad is the newbie. My brother has a couple of hydros. They're old Dumas Atlas's. Although, his kit came with flex shafts. He's had them 20 years. We got out of the RC world for many years and just got back into it last year. Dads Miller is from the same vintage. Maybe he got one of the first versions that didn't have flex shafts. They could have changed to flex if everyone was having problems like his, way back when.

Were very much old school since we've been out of it so long. The big 3 in our world: Dumas / K&B / Futaba. Back then, Prather was the cats meow, but Dumas was cheaper..... And let's not forget Tower Hobbies. Although, they appear to have just about dropped their boating line. And now MECOA handles K&B.....

tnltyme

Good point. Although, if his engine bay is 4 3/4, he buys a 5" mount, that leaves only 1/4 he needs to lose(1/8 per side). I'm guessing the spacers are wider than 1/8(I really don't know tho). If he were to take the spacers out and the mount was then 4 1/2 wide, or whatever, he could epoxy the proper thickness of wood to each side tomake up the difference.

Hydro Junkie

From what I've read, he is probably lucky the boat wouldn't get up and go. Seeing this in a post, The C.G. is approx 19 1/2" from the stern. I believe when they tried to find it by just holding it with a couple of fingers at the lake it was about 6" behind the sponson. has me thinking the boat would have SUNK the first time it got up to speed. The CG needs to be within an inch or two of the sponson transom. Right now the boat is monsterously nose heavy, making it want to dive. There is nothing wrong with using a solid shaft, just never seen one with a wood casing around it. You can use either an open solid shaft with a stuffing box and strut or a flex cable with strut. The real difference between the two is adjustability, the flex can be adjusted in seconds where a hard shaft can't. When you said his boat only weighed 5 or 6 pounds, was that ready to run or just an emply hull? I've never seen a Dumas hudro that light if built per the instructions. When I built a 36" blue Atlas years ago, the hull alone weighed almost 8 pounds EMPTY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

tnltyme

Hydro - The 5 - 6 lbs is ready to run with an empty gas tank.  Granted,  like I mentioned,  he's using a bathroom scale,  Weighing himself,  weighing himself with the boat and coming up with a 5 - 6 lb difference.  Not a great way to weigh the boat,  but at a moments notice that's what worked.  I guess he could bring it to a post office and weigh to be more accurate.

Am I wrong on this,  but,  if the CG is 6" behind the sponson instead of 2",  wouldn't that make it tail heavy?  Because if you moved your fingers 2" behind the sponson the rearend would drop and you would have to add weight to the nose to bring the rear up...  The tank is also in the nose,  so when that is full,  the CG should move forward a little....

Hydro Junkie

You're right, I got it backwards. Not often I make a mistake like that[:@]
Okay, that means it would have blown over if it ever got up and ran, meaning some serious damage. Dumas boats are known for being tail heavy with the radio box in the back, but by adding a wood "tunnel" and filling it with epoxy it makes things worse. What I would do is lighten the back of the boat by making some serious changes:
1) pull the bottom off the boat and get ready for surgery
2) move the fuel tank under the deck beside the engine
3) cut lightening holes in all the enclosed underdeck framing
4) move the radio up to the front under the cockpit
5) replace the bottom
6) install a new stuffing box and strut, solid or flex don't matter. If you go solid, the prop centerline needs to be even with the bottom of the sponson runners
7) repaint and test

Here's what I did with a boat built from plans, just for an example

JWMods

Thats a good point, I know the O/B 11's the needle had to be practically falling out on the first runs,, I think the needle does fall out at 6 1/2 turns. I started mine at 5 1/2 out and brought it in as several tanks got emptied. The 11 was a good running engine, O/B or I/B and the cool thing about the carbs back then is that they weren't linear. Which meant that the engine would try to digest all that fuel with the needle out that far, where an O.S. carb would not.

JWMods

Oh His Dad is gonna Love seeing That List,[sm=stupid.gif]

Hydro Junkie

Now tell me something I don't know
In a nutshell, that's why I don't do kit boats. I have a Circus Circus, an Eagle and a Pay'N Pak 20 all sitting in my garage, never to be built. I'm using the Pak right now as templates to build improved, lighter boats and will be doing the same with the other two, build threads will come later on each

kgibson4

My Feedback: (4)

HJ,

I agree, a kit is just a place to start from. But then again, the first boat I built, I wouldn't have known what to change on the kit. If I could do it over, I wouldn't have spent a lot of time on an intricate paint job before I had put the boat in the water and found out what needed improvment. Like I said before, it's a learning process an that's half the fun. I know I learned a lot from going to the lake and talking to more experienced boaters.

I'm really looking forward to those build threads.


Ken

tnltyme

That's why I'm talking to the guys on this forum. Alot has changed in 20 years!

kgibson4

My Feedback: (4)

And if you could take your Dad to some 1/8 scale unlimited races, there's a world of information there. Racers love to bench race, too.

Ken

tnltyme

That's the problem, boating has all about died in my neck of the woods. Duluth, Mn. used to have a boat club an weekly races. I guess it got hard to find a spot to run AND keep it. So that's why I run up to N Mn to run with my family. It's not a whloe lot of fun being on the water by yourself. The closest place where they race from me is in MPLS, Mn. And that's not exactly very close to the homestead.....

A sidebar. Is there a way to multi quote so I can answer a bunch of members in 1 post?

R.J. West

Hey HJ,

Why dont you show us some boats that you actually did finish instead of always showing us half done pics like you have been for the past, uh....5-6 years?


P.S... A Eagle is way better than a "Turkey"!!!

Hydro Junkie

In this case, a partially finished boat is more instructional and helpful than a finished one. I think you know the other reason I used on older picture BTW, have you been reading your PMs in the other forum RJ?

Blackout

Like others have said it sounds like the prop angle could be wrong. Convert to a flex shaft so that the angle is easily adjustable. A picture of the drive system would be great.

tnltyme

That's an understatement! Needless to say, it isn't going to happen...

tnltyme

JW, I'm glad you replied to Skyray's thread. That's exactly what the instructions for the motor called for, 7 turns I believe. As you know, the needle fell out. So, it is my understanding the instructions for the break-in setting were ignored and they went on their own. I wasn't around during the initial running of this boat. So what I'm reading here, it is set way too lean which is compounding the problem. Like was mentioned, the motor wants to die as soon as it hits the water from the lean setting which obviously isn't then trying to push the nose up.

As it stands, it's tail heavy which is good for now to try and get the nose up on launch. If we can plane it out we'll just have to run at a slower speed to not blow it over. Once we can get it on plane on a consistant basis, we can then tune it better for high speed runs by getting the CG moved forward.

I think we need to start from square one b/4 wemake any major changes. Step one is to fatten up the needle setting and see what happens. It may still nose in, but, we can at least eliminate the needle setting as part of the issue....

This is the first 11cc in our marina. Everything else is 7.5 and 3.5. It's definitely a learning experience.

Thanks for all the suggestions.....

tnltyme

One more thing until we try it again. I'll be sure to take pics before run it. Also, on that K&B 11cc I/B, what's the best way to start it. It's very hard to start since it isn't broke in yet. Fattening up the needle is going to make it even tougher. We loosen the plug to relieve some of the compression, which helps. We open the throttle some. I've also heard about clamping off the fuel line until it starts so it isn't flooding the carb. Is that a good practice? Any other tips?

Thanks......

JWMods

Hot batteries are the first thing, put in plug slightly loose, the person starting can hold the starter in one hand and pinch the fuel line momentarily with the other to ward off too much fuel. This is the method I use for super rich o/b bench running,, having someone else run the transmitter can help hold the boat down. 12 volts for the starter on some 67's can be tough even with with the plug loose. Many guys run 24 volts on they're starting systems nowdays.

If you get too much fuel pumped in it while starting you may have to pick the boat off the stand and let it run out the pipe and go at it again. You Do Not want to be lean, so using a hemostat on the fuel line I would not recommend. You could fumble around trying to get the hemo off and hit a lean condition and its possible to take the big end of the rod out in a micro sec.

Don't forget to tighten the plug once started,, the engine will be blubbering rich, thats good, and you may have to manipulate the throttle skillfully to keep it running while going to the water. Sometimes throttle can be on full with very rich setting comfortably while going to the water, being rich like that will not harm the engine. Several attempts at launch is not uncommon so keep your cool.
Have fun,

advanced builder

OK your right about Joe. But I think Joe Petro sells that mount also. Zippkit.com While your there CK out the Zippkit Rigger ,that old quicki 40 Will be back on the back burner. Here is my.21 Zippkit rigger the .12 is down lower on the page http://www.youtube.com/user/neillagarry

tnltyme

Thanks for the added info JW.  Me and my brother are ok with doing what it takes to get it working.  Dad,  however,  is not a young man anymore.  With is youth also went his patience.  We have used a hemostat in the past.  Maybe we need to rethink that tool...  Those hemos are not the easiest thing to take off.  I really don't care for them.  They also suck as hook removers for fish.  They always lock together and you have to fight to open them..