Hobbycity/Joysway "Sea Fire" Hydro

[Doozie870]

Pulled the stuffing tube out and found, only a small nylon bearing is keeping the water from free flowing in lol. Had a few bearings so I expanded the tube slightly and installed them, this should be better for now, but honestly she needs to be converted to more of a standard 3/16 type setup or possible a wire drive.

[sjslhill]

Thanks Dooizer, ordered mine today.

Steve

[Doozie870]

Good deal man, I have a couple of guys in our aircraft club really close as well. Ordered some props and a data logger from OE, so we can have some #s to work from.

[sjslhill]

Dooize called today, he hit 44.9 with stock prop and 2200 4S packs, nano tech.

[Doozie870]

Hey Steve, glad the boat came in and that your's does not appear to have the coupler problem. Still taking on water through the driveline, even though its much better, not acceptable. I butchered a p220 trying to bore it from 3/16 to 5mm, so played around with the stock prop, achieved 44.9 so far, she seems to like the nose up. Put the batts all the way back in the tray, and the strut as high as it will go. Still needs some tinkering, may notch the strut bracket to allow it to go up some more, and possibly move the batts further aft by removing part of the tray. I would kill for some octura or prather props with a 5mm shaft bore to try out. Here is a quick vid right before the batts dumped. NOTE there does not appear to be low voltage cutoff on the esc.

Yup thats the gps on the hatch

http://www.youtube.com/watch?v=b4jLoxH8vMc

[Scott T]

Doozie,

Check the fit where the stuffing tube enters the strut. Any gap there will pump heaps of water into the boat.

Looks like an interesting project.

[Doozie870]

Looks like a snug fit? Going to remove the entire drive and double check everything again.

[GTX]

The boat actually looks like it goes better than I thought it would. How does it turn with no turning fin ?

Have you see the video of the Superior version of this boat, that thing looks insane fast, I wonder what motor the faster unit has in it.

Keep the updates coming, seems like an OK boat for the money.

[Doozie870]

So far I have not really pushed it in the turns (coming soon), seems to turn ok in both directions at slower speeds, has a real sharp angle on the sponsons.

Completely stripped the boat and found the entire bearings were rotating in the tube. Removed and soaked them in melted vasiline, after it re-hardens, will keep the glue out. Epoxed them back in place. Also filled in the weave?? of the flex where the bearing race rides with solder (sanded down) as there was a little play between the 5mm flex and the bearing race. Noticed some end play in the motor, so added a thrust bearing. I do not prefer the strut being the "bottom out point" if you will. Motor needed some up angle for a better alignment, I achieved this with some washers for the time being. Silky smooth on the bench now. May be able to salvage the p220 by reboring and sleeving it back down at a machine shop. Weather sucks here will run again when we get a break.

[Doozie870]

Quick update.. Relocated the water outlet fitting to an area where it will be more visable. Was finally able to get the P220 on the boat, its far from being true at this point lol, but should be good to test with. Left about 1/16th gap between the drive dog and the strut, really do not expect much contraction with this size flex, but marked the strut anyway to see if its going to rub. Off to the lake!

[FighterCat57]

FYI- that is the exact same drive tube setup as the Surge Crusher, check out that thread for several good solutions on stopping the seepage. I run one, bone dry now.

For starters, adjust the prop dog so it is snug against the strut. It's a two piece drive shaft/coupler, so it does not contract under load like a normal cable. The other solution is to drill/tap a set screw in the coupler or epoxy the drive into the coupler, allowing the shaft to contract tight against the strut.

I just replaced the drive/strut with a 4mm HOTR setup and have been very happy with the results.

Another solution was to use a .187 teflon liner and 9/16 brass tube as a stuffing tube and tighten as above.

All have led to dry hulls and happy owners. Except the hulls cracking around the motor mount!

[FighterCat57]

Quick update.. Relocated the water outlet fitting to an area where it will be more visable. Was finally able to get the P220 on the boat, its far from being true at this point lol, but should be good to test with. Left about 1/16th gap between the drive dog and the strut, really do not expect much contraction with this size flex, but marked the strut anyway to see if its going to rub. Off to the lake!

Looking at the third photo, looks like the teflon washer is missing? This will cause a leak.

HTH

[Doozie870]

Thanks for the info.

Well this was a very short trip lol. Almost no cooling water flow, hard to believe that moving the outlet maybe 3/4" higher cut it back that much. Needed to add down angle on the strut to cut back on porpoising, which is unacceptable to me, so the batts will need to moved back more. Not much change if any with the P220 top speed wise, but it does run a lot smoother with a better holeshot. Going to drill out the rudder pickup a little bit and do a batt relocation. Will take a vid of the next run.

[sjslhill]

Looking forward to your numbers tomorrow.

[Doozie870]

Pretty good run today, no numbers still playing with the cog, should be about the same, around 45 or so. Moved the batts aft 2" this really helped, now that the front is a little lighter I can drop the strut down some, as it seems to be dragging in the rear a tad. Shes getting real close. Motor esc batts coming in ambient lake temp.

This run pulled 2350 mah, not to bad considering no turn fin.

http://www.youtube.com/watch?v=Frsz9wyJMpQ