DRAGONFIRE81M

i havent tested it yet i have a none brace set up in big blue but i havent gotten it wet yet to see . try it out and it it needs it you have the extra one i sent . you can do a tub test to see what happen . that way you dont have to rescue it if it goes wrong

asupervee72

i want to go to the lake but it is windy []

damfurst

I used shoe goo to secure the grate on the knock off. The jet skis have the screws already as part of the lower intake so that's why they were used along with some silicone gasket maker. epoxy would also work, but shoe goo is not as hard to remove if I decided to change things around for some reason. The grate I used is from an air filter for a car that I had burned in my wood stove in my shop. I works great so far.

Sorry to hear about the wind at the lake. We're supposed to get snow the next few days here.

mineralvann

I'm thinking about making a micro jet and was wondering on what hull i should use, so far i've got three options. 1. BBY Micro patriot http://www.bbyracing.com/elecmicrohulls.asp 2. Rennboot-Klasse "Micro-Mono" http://www.slomka-modellbau.de/micromono.htm and 3. Mini rio http://www.rcuniverse.com/magazine/a...rticle_id=1012 . Would like to avoid having to buy the mini rio as it will be about 4-5 times more expensive then the others but i'd also like a boat that is stable at high speeds. And if i remember correctly someone said earlier in this thread that the bby was difficult to balance right. I was also wondering if the graupner 29mm would fit but after seeing the pictures from bayshun with a mini jet i'm thinking thats out of the question as the mini rio is the biggest of the boats i've found so far. And as i would like to have reverse but only have a 2ch remote i was wondering if a esc with reverse would work insted of a reverse bucket as i dont have a 3/4ch remote. I'm thinking about powering it with 11.1 lipo cells with 2400mah weighing in at about a 100grams powering either this http://www.dealextreme.com/details.dx/sku.12828 or http://www.dealextreme.com/details.dx/sku.20082 are they in the correct rpm range and are the batteries light enough? if reverse on the esc dont work i will probably use a mystery 40a/60a esc from this site instead(assuming a flight\heli esc works like a boat esc. just need to waterproof and watercool it). And if anybody know of any other sites that sells cheap micro hulls or have jet drives cheaper then cornwall models please let me know.

asupervee72

i have a speed controller with reverse and my 29mm graupner drive reverses just fine without a bucket, though i dont ever use it other than to say hey look i have reverse

sundogz

Ebay sale: Heads up - This looks like it would make a good jet boat and is a good price (right now). You're welcome! [sm=wink_smile.gif] [link]http://cgi.ebay.com/RC-FIBERGLASS-SPEED-BOAT-HULL-RADIO-CONTROL-27-x-9_W0QQitemZ170325505372QQihZ007QQcategoryZ2564QQss PageNameZWDVWQQrdZ1QQcmdZViewItem[/link]

Quicksilver

but look at the aft of the boat, the hull has very noticeable curve. Would not be good. It'll bounce like crazy.

Quicksilver

You dont need it. I would beef the area where the stuffing tube enters the boat. Best imo, is to use fiberglass and do it on the inside of the hull, not in the duct. I would makes sure that the shaft is completely center while the fiberglass is drying. Just rotate the impeller.

Grates? I've talked about that to death, I don't em. imo gives you a false sense of security, just order some spare impellers, before you break one.

Madmax160764

Ho ! sorry it's a 2030 bl180 walkera motor whit 3200kv

asupervee72

did you mean something like this?

grael

If you mean what I think you mean, then yes, it's bad. I think you are talking about the "stator" on a Jet pump, it's almost as important as the impeller.

The stator vanes take the water that's spinning as it comes off the back of the impellor, and curve it around straight again. You will know, because if you run it damaged like it is at the moment, the water will come out of the outlet spinning in a funnel shape.

I've been making and moulding my own outlets, and I make the stator one piece with the outlet nozzle so it's a lot stronger, no joints.

asupervee72

nope that part is good, i was talking about the part before that, it comes before the impeller, stator goes after impeller right

lomdel

I built a few FE boats recently and would like to try my hand at a jet drive one. Which of the CEN Aquajet, Supervee27, Shockwave 26 or Formula Fastech hull would be your preferred coice for a new build? And drive options as well...

asupervee72

if those are the hull choices i think i would go with the sv, it's the only one that is fiberglass and not abs, i like the way it looks the best, unless you want some figures to "drive" the boat, the v isnt too deep so i think a jet would do well on it, stick the 40mm drive from graupner in it and some decent electronics and you should be movin. if i rated it in order of what i think would be best to worst it would go sv, cen, fastech, shockwave. look here for some drive options http://www.westbourne-models.com/erol.html#1X0

lomdel

What other hull choices are there in the 26" to 31" category?

Diegoboy

Huh? I could have swore the [link=http://forums.offshoreelectrics.com/showthread.php?t=5468]Fastech[/link] was Fiberglass. [X(]

asupervee72

oops it is fiberglass, i dont know why i thought it was abs, just looked like the top would be plastic cause of all the details, either way i dont think it would change my decision, seems like it has a deeper v than the sv. I only own a sv and looked at all other boats at their respective websites. Im sure there are plenty of hulls in the 26-31" category. these are just the rtr hulls or 90% rtr, though i figure you're just after the hull

sundogz

Quicksilver, are you talking about that overhang on the transom? That can be cut off easily enough (if necessary). And the bottom of the hull (see pic below) looks like the hull on the ABC Jet Ski and it doesn't 'bounce'. I dunno. Looks like an easy build.

And while you were gone we did some experimenting and found mesh grates do in fact protect the impeller and don't slow the boat significantly - this is not just my opinion. Fishing line, leaves, pebbles, etc. can muck up the works, take out an impeller or burn out an esc. Seems like an easy prevention - and buying/replacing impellers doesn't sound like good advice to me ([sm=75_75.gif]my opinion).

Grael, you were right on that lipo - it was dead and didn't know it. Took an amperage reading - zero. Shorted the leads (don't do this at home kids) there was a small spark and after that, zero on the voltage and amperage. Never seen that one before - live and learn.

Diego, have you had a chance to run that Fastech in fast (frothy) water yet? I'd like to see how it handles. I bet it will do real well with that hull shape - Creek/river running is not about speed but torque mainly. And that boat has torque! You can tell the c.o.g. is set right. Looking forward to the results. Sdg

Quicksilver

yep! and so you know, we are talking about the same part. Mine broke off many years ago and in fact no version of my jet-villain ever had them in place. As far as a stator yeah you need that.

Quicksilver

What I'm referring to would be called rocker? I'm not sure of the term, but the back of that boat curves down right before the stern, it'll act like a trim tab, but one you cannot adjust. Hopefully the pic illistrates this.

Here's my deal, I've blown impellers with and without grates. Essentially all I do is run rapids. I feel they're useless if you are putting the boat in danger constantly. If you are using the boat strictly for a pond, you might want one, but I'd still not use one. Rocks get through the grates, leaves can hang on the grate, fishing line can get through. Now I'm not saying they don't work a bit, but really, unless you can build a really really good one, I say don't make one at all.

I've made one out of brass, made one using steel rods, made one out of aluminum stock and made one out of hardened steel saw blades. All of them failed when in rapids or in a lake. There's tremendous forces being put on the grates. Perhaps, with a light boat and lipos you can make one work effectively. For the most part, people say they added them and then never say whether they worked for 20+ runs or so. My boat weighs a lot, 16 cells, with a 700sc motor and the armor, it's up in the 6-7+lb region. Nothing is going to stop a rock from getting into a duct upon which the boat is essentially riding on.

Take 6lbs+20mph+force concentrated on the 10% of the hull that has the intake= forget about it.

If it works, great!
It doesn't work for me and if someone really makes a bullet proof one, I want to know how to make one ASAP. I haven't bothered getting the jet boat ready this year, because I'm on my last perfect impeller. My surface drive villain is like my Ferrari and the jet-villain is more like a Jeep.

Quicksilver

there is the villain but that wouldn't be really original. If it were me, I'd try the fastech, but if money were an issue, which it usually is with me, I'd probably find a cheap used SV hull. The aquajet works fine, believe we have two of those.

Hey this goes to everyone. Can you guys all send me a PM with what boat(s) you're using, jet unit and motor? Finished boats that work properly only. I could make a nice list of boats that we've built for future jet boaters.

sorry for 3 posts in row, I apparently miss a lot by sleeping....just trying to catch up quick before work.

sundogz

Quicksilver, could you have that backwards? I've always thought rocker goes up at the stern (hull bottom looks like the rocker of a chair) and can cause the nose to bounce up. But if this boats' hull goes down - wouldn't that cause the nose to stay down? (like trim tabs). Should be a good thing. And you're right, the bars or grates or rods that come on some jets don't work well. I've had pebbles go right through them. So we're using mesh expanded metal or 3/16" welded screen (like large window screen) and having good results. Doesn't sound right, but works! Sdg


Note:I've come back from the future to add a couple more photos for reference 5-25-09 Sdg.

sundogz

BBY OM21 Rapid Runner update:

I finally got a chance between the rain storms and windy days (man, what weather we've been having!) to try out the boat after modding the intake to lessen cavitation and I'm happy to inform you that it worked! Cavitation has been reduced tremendously, but now I have a different problem. The boat now hops badly. I tried moving the battery forward and adding more weight (another battery) but it didn't fix the problem. This is the first run after the mod: [link]http://www.youtube.com/watch?v=qyaKqkL-Xh8[/link] Again sorry for the cr*ppy video, my camera's not very good. It is fast, but hops terribly.

So now I am wondering if I should install trim tabs, or adjust the steering nozzle down some. All ideas/opinions are welcome. Sdg

areseaer

I would adjust it up. From what I read about full size jet boats is that the intake should be parallel to the water line as the boat sits in the water which would make the boat keep the stern in the water. It sounds like your boat is riding up out of the water. Maybe you could try to get your water line parallel to the jet intake and see if that changes anything.
It's something to try anyway.

asupervee72

ill send you a pic of mine when it is back together, i dont think this hull is even made anymore so im pretty sure im the only one that has a jet in it

the sv and the jet boat are getting painted, just primed right now