5150Cat

Matt,
Yes, that's right. The Tygon......not tioga. Not sure what I was thinking there. Good call on keeping it short too. Never would have thought of that. Maybe I'll mount them right to the engine rails up in front of the engine.

I think you've sold me on the idea of under the rear there for the air ducts. I think I'll grab some NACA ducts and add a few of those on top and have a couple large outlets underneath and above the drives. I think that's genius. I'll get some of those ordered and start the input of those. Think a couple of large ones would suffice for that large snorkel I put on the top.....like I said I'll probably block those side ones off. Make them just for looks.

So when you say engine failsafe. Are you talking about a kill switch for the engines or more of some type of failsafe for the radio if the boat loses signal? I have the failsafe built in to my radio. But don't have anything else. I guess I'm clueless on this part of things too. I'm going to look into the kill switch thing for sure. Just makes it nicer to pop that hatch a have a button to poke at to kill things.

Mike

Justaddwata

My Feedback: (3)

The engine kill failsafes will actually kill the coil if there is any disconnect with the radio. If your battery disconnects in the boat for example - the engine kill will shut it down (Uses power from the receiver to close a relay to unground the coil. If power is lost the coil is grounded). My Reckless has a pair of them from Europe but theres no name on them



Radio failsafes work well but not in 100% of situations (like power failure, servo failure, linkage failure etc). The engine kills are not essential - just added insurance (and like insurance - not as affordable as it should be )

5150Cat

Is this something like you're talking about Matt?
http://www.zenoah-blackbox.co.uk/Products.htm

This looks similar to the ones you have Matt:
http://www.rc-car-online-shop.de/lsh...akkuzubeh,.htm


My question for the day has to do with the gas bag placement. I have a couple options. I can make a protective clear plexi "gas tank" that will hold the bag and protect it from anything sharp. My two options are either in the area just under the drive cable between the engine and gearbox, or in front of the engine. Not having the bag yet I'm really not sure how big around it gets. I don't know how full I'll need to fill it either.

My other option would be to place two 500ml bags on each side of the engine. This might be a good option instead of the single 1000ml bag. As you stated Matt this would make it easier to tell how each of the cylinders is tuned by monitoring fuel consumption. I could make two clear tanks then to hold the bags. Or for that fact I could use two 1000ml bags and just not fill them as full......

So many options and I have so little knowledge on boats!

Mike

Justaddwata

My Feedback: (3)

Those look to be the ones (Engine Kill failsafes).

You may want to see how the boat balances out to make a determination as to where to locate the IV's. A single IV will be a lot easier to fill/burp but a pair will have other benefits. I would stick with the 1000 you have and evaluate from there.

I would hold off in securing an enclosure for the IV until you have the boat running and can see how she handles with tank in front of motor vs behind motor. Dont worry about the knowledge - you gain it as you go!!

5150Cat

Back to the NACA ducts. I know they are probably pretty efficient in sucking air in. I'm wondering how effective they will be to remove air......I would assume it would be just as good?

Just thinkin......

Mike

FlogginHarvey

MAtt, I also use the ones from Europe. They Are Isamtec Kill Switches and they are awesome. Using them on the Mystic and Skater as well. You can use one brain in the radio box and two relays outside the box...available through MHZ Germany. Just need to know whether you are using the Futaba FASST or not...

MHZ Germany does NACA Ducts as well as Model Center Lorenz in Germany. He is GREAt to deal with also. NACA's work GREAT! Using them on the Mystic (as have MANY before me). The rule on venting as I have learned in three times out what is allowed in. I think Lorenz may also sell the Isamtec kill switches as well but not a 100% on that one.

The boats looking GREAT! The Mystic is in the paint booth as we speak...getting pumped up!

5150Cat

Nice Harvey! Thanks for the info. You don't have a web address for that Model Center Lorenz do you? Wasn't able to come up with much online. I'll get an order to him going soon though. I'll check out his scoops as well.

Like Matt suggested I think I'm going to mount some of the vents under the rear of the ledge of the boat just above the drives. Should be able to get some good sized outlets back there and it will still be stealthy and not mess up any lines on the boat.

Looking forward to seeing the Mystic when it's done.....be sure and post some pics!

Mike

5150Cat

So I found this:
http://www.asaad.com/killswitches.htm

I have a question on the kill switches though. I'm thinking there are a couple kinds from what I'm reading. One that isn't controllable from the radio and one that is. As long as it did the job is was supposed to I wouldn't think it would need to be controlled by the radio.

Here's my question though. I only have 3 channels on my 3PK. So that gives me steering, throttle and trim adjustment. Most of the kill switches require a plug in the rx to work. How does this work if I'm already out of channels? Can't seem to find out how that works online anywhere.

Mike

02f350psd

My Feedback: (3)

I think Matt suggested this somewhere but you can always set the carbs to that you can use "reverse" on the throttle to kill the motors instead of an additional channel for killing the motors.

5150Cat

Yeah I'll probably do that psd.....I think Matt mentioned to do this as well as extra insurance. I think. Extra insurance is all good in my book!

Mike

5150Cat

Ok so here's my mock up of my exhaust box. Not sure how this is going to turn out but it seems right in my head so we'll see. It's really tough to get it all fabbed up using hot glue and styrene but my buddy needs templates so he can knock them out in stainless for me. Then as soon as my metal guy gets back from Texas I'll have him weld everything up.

We'll see how it turns out. Could back fire on me but I think I'm onto something.

Mike

5150Cat

Getting everything in the hull tonight to see where I'm at I came across another question.(go figure.....)

On the big boats. Do you guys normally use solid steering linkage such as a threaded steel rod type thing? Or is it possible to use a pull/pull cable type system?

Seems the cable idea might work out but I've always used the solid link type thing. As long as it turns I can't see it making a huge difference?

Mike

isola_d_elba2007

You can use a pull pull system with threaded steel rods if you want ...if i find a picture i post it...

You have to use a rudder like this


Uploaded with ImageShack.us

And a servo set-up like this with two steel rods



Uploaded with ImageShack.us

FlogginHarvey

Here you go for Isamtec and Modelblaucenterlorenz

http://www.modellbaucenterlorenz.de/impressum.html

http://www.modelgasboats.com/Magazin...fe_by_Isamtec/ review on the switch

http://www.isamtec.de/isamtec/Killsw...XT_Benzin.html The Futaba NXT is for the Futaba FASST systems only but he does make different versions for the different radio systems. I really like them.

The other nice kill switch (in my opinion) the RCKillSwitches killer bee. The price on the Killer Bee with waterproofing and indication light is pretty close the Isamtec switch as it has all of this stuff on the main/base unit through the whole lineup

5150Cat

Thanks Harvey! I'm going with the Killer Bee setup. Contacted them and that seems to be the good setup.

Thanks for this links!

Mike

5150Cat

Well I officially have to say that I'm not happy with American RC Boat company. Can't see me ever ordering from them again. I ordered a fuel tank and six shooter filler 2 weeks ago and have heard nothing. After a call, two emails and even a text to the number I'm not sure what the hold up is. I don't mind waiting but it would be nice to get some confirmation of some sort. Know what I mean?

Anyone else have issues with this guy?


On a better note. Took the exhaust parts over to my buddies house last night. He is going to start on cutting parts this week and I should have that going within the next few weeks. Also cut the top hatch out of the boat and he's going to look at getting some micro small hinges made for it. Pretty sweet. Pics as I get them!

Mike

5150Cat

Finally got some more work done on the boat last night. I'll get pics posted later.

I cut out the hatch.....which sucked by the way. But finally got a hinge and latch system on it so I plan on mounting the kill switch accessible through that hatch and also it will be nice to see the fuel level. Should be a nice touch.

Also ordered a FASST extension for the rx. Since I've heard it's not going to hurt and there can be some interference with the inline twin and the carbon fiber in the hull.

Also getting ready to order servos. Been having a heck of a time figuring out which servos to order. Think I've settled on Hitec's high voltage servo that can handle 7.4v. It has something like 400oz of torque or more which is plenty I would think. And I can run just a standard 7.4 lipo and shouldn't have any troubles.

Slowly.......coming together! Pics tonight!

Mike

FlogginHarvey

I think you will be happy with the RC Kill Switches kind. I use one of those on my wife's Scarab. It works GREAT.

On the servos, if you are still using the twin S6 drives then go with a twin set of servos. Most I see with S6's stick with the quarter scale servos and link them up with 4-40 linkages and ball ends. There was a couple of fly RC sites that Peter Mueller turned me onto for the Mystic and they worked great.

The Rhino Digi's are MONSTER's and water resistant. Davesmotors.com has them for the HPI Baja's. Two of those and you will be as right as rain. They are around 350oz on 6.0V still water resistant...they are now sold under the Hitech name in the States. Here's a link to towerhobbies:

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXYUM6

http://www.chiefaircraft.com/rcmsec/...ories/SWB.html
http://www.airwildpilotshop.com/prod...00108311040163

5150Cat

Ok Floggin, now you're just rubbing it in. You have that awesome cat on it's way, and now you're trying to tell us your WIFE actually has a boat?!?!?! C'mon now. Is this a true thing or is this like my excuse for my toys....."it's uhhhh for my wife!" Either way that's cool!

I'm looking forward to getting those switches ordered. Hopefully this weekend.

I am definitely doing two servos for the steering. I was even all over those servos you were talking about. I have that exact same servo in my 5T and my 5th scale street car. They are awesome. But I just don't trust BEC units anymore. I've seen to many fail or burn up. So I want to eliminate that. So I think I'm sold on the Hitec 7.4v HV servos. That 5755MG only has 250 oz in at 6.0v. The 7954SH's that I'm looking at have a monster 403 oz in at 7.4v......And that's just crazy! I'm just liking that all the power will go to the servo and I don't have to worry about amp draw. The other really nice thing about running a 7.4v battery is the fact I can use my Maxamps 3100mAh lipo and it will run those monster servos literally for weeks if I wanted it to. And the battery is a nice and tidey 3.25"x1"x1". Very tiny and light. I highly recommend those Maxamp guys too. If you call them up they will usually throw you a discount right over the phone. Wicked batteries too. They have 100% of my lipo business.

Mike

5150Cat

Got some more pics also. I got the hatch cut out......and holy crap that didn't suck ***** or anything. My fingers still hurt from the modified saw blade I used to cut it out. The hinges I ended up using were just the hidden gear door latches used on the airplanes. Looks nice and clean and still very functional. It all looks like crap right now due to the fact they are only temp hot glued in there. I'll get them glassed in one of these days......

For a latch I used Dubro's wimpy cheesy little hatch latch. It is barely worth the $3 I spent on it and I expect it to fall apart the next time I sneeze. So my machine shop buddy is already starting on a modifed version of the same latch only beefed way up and out of black ABS plastic. Much stronger, much more reliable and black! How can I go wrong there?

The exhaust has been put on hold because he's so overloaded with real work and other parts I've given him. So I have to be patient. But it's all in the works.

Couple more quetions for you guys. First off on the fuel bag. Finally got that today after a few weeks. You can see the pic......how the heck do I plumb that thing? It has a "Y" in it. I know I am running a lead from each motor to a "Y" harness. From that harness it goes into one of the leads on the bag.....I think. But where does the fuel filler come in? And it has two holes....one for filling and the other is like a breather? I can get another pic of that if needed. I'm clueless and need to sit down and really figure it out.

And what does everyone think as far as engine break in. I don't have a small pond or area of water that I can put the boat in water(that's not salt) for a short drive. What does everyone think about locking the engine to a stand since it's already in the rails, leave it hooked up to the gearbox so it's not free spinning, and breaking it in right here in the driveway? I could get an empty milk jug or just the garden hose to keep water flowing? My buddy thinks that's a lame idea and I just need to get it in the boat and do it that way. Any thoughts here? I think at least for the first tank to break it in nice it would be cool to have it out and accessible for changing idle and carb settings. But what do you guys think? The throttle servo is attached to the actual engine assembly so that would allow me to still use the radio also. And obviously I'm not planning on pinning it WOT with no load.

Mike

5150Cat

Ok, I think I have the fuel system worked out. Just took a second to sit down and focus on things. My question is this though. There is a "T" in the line that the goes from the filler to the tank/engines. What's to keep the fuel going into the tank and not flooding the engine at the same time?

And the fuel tank fill has an additional hole on it. I'm guessing an overflow or breather? Where should I route this?

Mike

FlogginHarvey

Bags don't need breathers. You just gotta be careful on burping all the air out of it when fueling. With mine, I usually hook up the filler pump, unfill to prime the pump and then fillerup...The Slimline can/pump combo is AWESOME!

The first time you fill them let it sit full for a day or two becuase the bags get super soft the first time they take fuel...after that they season up and are great. NEVER empty out all the way...it will get HARD!

5150Cat

Hey floggin,
The tank doesn't have a breather......but the actual fuel filler neck has a breather. I'm just not sure where to route that breather?

Mike

Justaddwata

My Feedback: (3)

What filler are you using Mike? I would either block it off or use another filler.

IV bags must not be vented. Any air in the bag will shorten the life of the bag (long term) and cause you to stall out early into the run. As Trey mentioned - you have to burp the bag when you fill it to purge out all air before using the tank (after every fill). Also as mentioned - the bag will usually (some brands do not) go through a sort of metamorphosis over a couple of days when first fueled and will actually get very soft (almost jelly like) and even weep fuel for a day or two. Fear not - the bag does not leak and will firm up and be good to go. It should not be used during that period. Once the bag has metamorphosised it should never be stored empty or with air in it (air inside will make it brittle). IV bags are fantastic but more work.

5150Cat

Matt,
I'm using the MH$ filler. I tried to get a good pic with the cell phone but it failed. I'll bust out the SLR this week and see if I can't get a better shot of it. Basically I think I'm making this part tougher than it is. I just need to block it off.

The filler is basically a female piece. There's a male part that hooks up to the pump that you lock in there. When you lock it in place this hole I'm talking about is blocked off. But when it's out and the filler is capped off this hole is for a drain I guess that feeds right back into the tank.

Hopefully that's making sense. I'll get a good pic this week but am 99% sure I just need to block it off like you guys said.

Mike