Scott Schneider

Dana,
Bummer ... yea a lot of vibration going on at that connection. Unless alignment is dead on and runout dead even you got [:@]
have a new shaft cut without the step and work on the runout of the dogbone coupler to get it perfect.

Honestly tho, with the engine in A/V mounts and dog bone couplers needing perfect alignment, really not the ideal connection type IMO.

infinityteg

My weekends running was just carnage. took the boat to my auntys place who has a small river running through her property. its about 6-7' wide which is probably not quite enough when your doing 50-60k/hr. After seeing all the real sprint boats, they al get beaten up a bit. The biggest hole has gone right through and it only the pool noodle holding the wood over the hole. and a broken pipe mount

cheers
steve

Scott Schneider

Steve,
But did you have fun

See an RCMK in there now for power, how it run for ya ?

infinityteg

it was a blast. just not long enough.

the rcmk is great. just that little bit more power than the Zen has made such a difference.

dicko

I joined the deck to my hull today. It's coming along now. Starting to look like a jetsprint.

I've got a build thread going over at the Snikwah site.

http://modeljetboat.com/forum/index.php?topic=14.0

Scott Schneider

You running the 3 or 5 blade impeller ?


Work faster, more hours, late nights .... get er done
Lookin good

dicko

I'm limited to the setting time of the resin at the moment. Typically it's our first cold week as winter sets in so the times are a little longer. I need to go buy a heap of parts before I get much further too. I just got a quote from Bruce at Gizmo Motors for a few things I need & once I have the cash I'll fire that order off. I'll have to get Ken at Retallick Engineering to fabricate a nice stainless header for me to fit the boat & also make me a pipe to suit the 29cc head I plan on putting on there. I'll also get him to modify the 29cc head too.

This is one of 2 builds I am currently working on. I must admit, I'm putting more time into this than the cat. I should probably get onto the cat soon, I plan on racing that in a couple of weeks!

After i mount the backing plate for the skirt bracket, I might have a go at laying up the carbon for the rollbar. I'll need to make a mold for that though.

infinityteg

Scott
I made the mistake of only getting the 5 blade impellor. i wish i had of got both now. but the lil extra torque from the rcmk has made a world of difference.

Dicko
Builds looking good. ive saved all the pics for future reference
I made my cage out carbon. I only done the female mold though. i used 5 layers of carbon uni's. Im not sure on the weight of the fabric now though, it is strong as ever though. i just used some 18mm custom wood screwed into a u shape and car bogged the corners into a nice curve. then used brown packaging tape layed evenly for the molding surface. it wasnt hard to sand the very small ridges the tape overlap left.

cheers
steve

dicko

That's funny, I use packaging tape for a lot of my molds too. The resin just won't stick to it & it's easy to pop parts off!

I have the rough measurements for Craig's Swashdrive roll bar & will make a similar sized one out of carbon. I found that if you squeeze the excess resin out of the carbon you can get a much stronger laminate. I plan on using the mounting blocks Craig provided with the kit to mount the roll bar to. I will probably only have time to mount the jet unit today & I'll get onto the mold over the weekend.

Cheers
Jason

Dana W

I came up with a solution . With what little drive shaft I had left on the pump I managed to find a round collet with set screws for the 1/4" pump shaft . I put a square drive collet on the engine . I installed a square drive flex shaft and now I'm good to go .

Scott Schneider

Much better set up


Reason I ask is because I have both and been running the 3 all along, but also running the RCMK Evo top end may have the power on hand for the 5 ?
Running the 3 acceleration is instant like a light switch and rpm is @16K ....
*So how snappy is yours with the 5 blade ?

infinityteg

well dana i dont think youll have a problem with the flex shaft set up. mine and scotts has held up like that now for a while.

scott
without being able to compare the three blade with the 5 im not too sure of the difference. I find the accleration of the boat very good. While running the Zen in it turning you could hear revs drop off a little but it is definitly not as noticable with the EVO.

cheers
steve

Scott Schneider

Hot dang !! .... found better performance, better intake loading and overall less blow outs and odd behavior with some intake mods !!
Added an intake bubble made from a tea spoon then attached just ahead of leading edge on intake. A bit deeper angles on intakes leading and trailing edges done as well. Together hull is working great as is without the C/G changes I though it needed

On smooth water now boat will run WOT without proposing what so ever, turns under full power generally brings a one point turn without loosing suction. Go crazy on steering and throttle boat will still unhook and do table top spins for giggles

Will post a few pics of the mod later tonight .....

Scott Schneider

Here is what the mods look like

Dana W

Interesting However I didn't have any porpoising with my CG moved back .

Scott Schneider

Dana,
I know likely a crutch fix for the forward C/G, but had to try it out.
But runs just great now, maybe the C/G will make it even better !!

** So with yours, what C/G % were you able to set yours up at ?

Dana W

I did what you suggested 27% .

Scott Schneider

Fair enough

wave waker

Dana W,

here's the pics, this is a 40x15 inches warehouse hobbies jetski hull. thanks


jul

Scott Schneider

Well that's very cool

infinityteg

Cool. that'll be an interesting project

Dana W

WOW , I didn't know they where making a jet ski . I'll look into what pump they're using .

cheesewizz69

Tony made a few of them in the late 80's and into the 90's. He still has the molds but I don't think they sold very well.

timjz

My Feedback: (1)

I've been thinking about building a boat like this for a long time. Would the KMB hold up long-term to a Zen/RCMK? I had a KMB drive a few years ago but never used it & sold it. I remember paying WAY more for it than they seem to go for now.

Would the KMB would be ok just for playing around? How much more are the Graupner drives & what kind of extra performance to you get?

daniel53

Hey everyone