ProBoat's new 29" Mystic Brushless catamaran

[tiqueman]

Sorry, yes one package. You will only use 2 of the 5. One in front, one in back. And the bushings have to slide out from the end they are in... unless they changed the strut but I doubt it. Thoers probably a lip inside between the two.

[desmobob]

Sorry, yes one package. You will only use 2 of the 5. One in front, one in back. And the bushings have to slide out from the end they are in... unless they changed the strut but I doubt it. Thoers probably a lip inside between the two.

Got it! Thanks very much.

desmobob

[desmobob]

I got the Mystic 29 onto the water again today. Much better...

* The howl did not return in three sets of batteries. I did use a different type of grease on the shaft this time. (I also sharpened/polished and balanced the stock prop.) The first time, I used MiliTech1 (my favorite gun, bicycle and general purpose grease) but I don't think it's billed as "waterproof" or "water resistant." Today, I used Amsoil Water Resistant Grease from the local auto parts store. It's the typical blue color, and lithium-based. It's not very smooth or sticky but it seemed to work better. I have some new strut bushings on the way, just in case. Do they need to be pressed or driven out or can I make a small hook tool and pull them? I haven't really looked at them yet.

* I brought the temp gauge. On the first run, the boat came back with the motor and ESC very hot (~120). Turns out the port battery had kinked the water inlet tube where it runs through the battery tray. I was fully engrossed in the high-speed handling and forgot to watch for the tell-tale stream out the exit fitting. I let everything cool down a bit, then ran another set of batteries being careful not to place the battery where it would put pressure on the tubing. After each of the next two sets of batteries the boat came in with both the motor and ESC at 94 deg. I may change the routing of the water inlet so it doesn't pass through the side of the battery tray to avoid having trouble in the future.

I noticed a good stream of water out of the exit at low-to-mid throttle settings, but it looked like nothing was coming through it at full throttle. What could be causing that?


* At full throttle, I was running nose-high and porpoising. I moved the batteries ahead and it didn't seem to smooth it out. I raised the strut about 1/16", so the bottom of the strut is just touching when I set the boat on a flat surface. I had the 5000mah batteries placed so their forward end was even with the forward end (rear) of the motor. On the next outing, I'll try moving them a little further forward and/or experiment with the strut position.

I was more aware of my battery condition this time and brought the boat in as soon as I started to notice a fall-off in top speed. The first two runs, the cells were at 3.85V. The third time, I took a few "cool down laps" after that and the cells were at 3.75V when I came in. I used an on-board cell voltage alarm set at 3.4V but never set it off. Good.

I sure love this boat!

Take it easy,
desmobob

[Darin Jordan]

* At full throttle, I was running nose-high and porpoising. ... I raised the strut about 1/16", so the bottom of the strut is just touching when I set the boat on a flat surface.

Generally speaking... when you raise the strut up, it RAISES the nose of the boat up as well. Lowering it lifts more of the rear of the boat out of the water, pushing the nose down.

I believe that my MG is setup with the strut flat against the setup board (even with the bottom of the sponsons), or perhaps just a TAD higher... There are lots of others here who have set these up who might have some info for you as well.

Glad you are enjoying the boat. That was the whole point in putting it out!!

[Make-a-Wake]

Get her wet today, had to do quite a bit of tinkering with the strut and batts to get her going well..............still got a bit of wah wah in her. I was running on some pretty smooth water and in one direction she settled down and the other she porpoised a bit. Wasnt much wind at all but i think going into the wind settled her down a bit. Ran an x442 and the ESC and Batts were barely warm...........not blown away with the speed, but then again im used to running my 60+ mph boats. My buddy ran his Geico with stock components and an x642 and we were basically equal on top end. Fun boat though, and turns very well, did flip her once on his wake and ended up rightside up. Should be fun to race as a threesome next week.

[desmobob]

My buddy and I had a blast with our boats this weekend. Another friend was there and he's ordering one as soon as Horizon has the RTR package in stock. :-)
The next time we run them, we'll put out some course marker buoys in the bay and the REAL fun will start.

Both boats developed the howling after two or three runs but greasing the shaft eliminated it. My new strut bushings should be here today or tomorrow, so that should no longer be a problem.

I did have one thing happen that I needed to ask about....

After running the boat several times now, the Teflon shaft liner is coming forward and hitting the back of the collet. I can see white dust below the collet where the liner is making contact and getting worn down. Does it need to be glued or secured in place, or is this an indication that something else needs to be adjusted?

Thanks for any information,
desmobob

[Darin Jordan]

After running the boat several times now, the Teflon shaft liner is coming forward and hitting the back of the collet. I can see white dust below the collet where the liner is making contact and getting worn down. Does it need to be glued or secured in place, or is this an indication that something else needs to be adjusted?

Thanks for any information,
desmobob

From my experience with these, it could be one of two things... 1) The teflon was too long and the prop thrusting forward is pushing the stub-shaft up against it, pushing it forward in the stuffing tube... or 2), and more likely... The factory teflon they used doesn't fit snugly into the stuffing tube and so the flex cable rubbing against it, with the spirals "screwing" upwards toward the motor, are pushing the teflon up. This can happen especially if you are using some sticky, thick, grease.

You might be able to fix it by fitting a piece of water tubing over the forward end of the stuffing tube. However, if I recall, there isn't a lot of extra material up at that end. Another solution might be to very carefully put a couple of small "dimples" into the forward end to keep the tubing from creeping forward.

I think on mine, which was the very first Production boat, and was received before they fixed the flex cable rotation issue, I had replaced my cable with an Octura, and replaced the liner as well. I had to so some "stretching" of the Octura teflon to get it to fit, but it's in there now and doesn't move. I also think it's a little more "slippery" than the stock stuff... which is more like a hard nylon tubing than teflon...

[desmobob]

I got the chance to make one run this evening and the Teflon tubing stayed in place. (I had pushed it back into the brass tube to where it started when the boat was new). Tonight, when I pulled the shaft to clean and grease it, I did something I read somewhere here on the forums: I pushed the cut-off end of a Q-tip through the tube to clean out the old grease and water. When I was trying to wrestle the piece of Q-tip out of the short open area at the motor end of the tube, I ended up pushing the Teflon tube back almost flush with the brass tube. I'll find out later if that's going to create a problem.

I was wondering how difficult it was going to be to remove the stock strut bushings so I could install the new lead/Teflon Octura bushings I ordered. When I removed the drive shaft tonight, the rear bushing was sliding out of the strut on its own. I guess it won't be too hard!

In an attempt to eliminate the last little bit of porpoising, I positioned the strut with the bottom even with the bottom of the sponsons, but also tilted it prop-down as much as the free play would allow. The porpoising was eliminated at all but full-throttle, but the boat seemed slower and I wonder if I had caused some extra drive line friction or a little bit of binding by tilting the strut down, even though it was probably only a degree or two. I returned it to level and hope to get on the water again tomorrow for further testing fun.


This boat has me wishing I could dig a big pond in my back yard.

Take it easy,
desmobob

[desmobob]

In an attempt to eliminate the last little bit of porpoising, I positioned the strut with the bottom even with the bottom of the sponsons, but also tilted it prop-down as much as the free play would allow. The porpoising was eliminated at all but full-throttle, but the boat seemed slower and I wonder if I had caused some extra drive line friction or a little bit of binding by tilting the strut down, even though it was probably only a degree or two. I returned it to level and hope to get on the water again tomorrow for further testing fun.

I got a chance to run three sets of batteries tonight just before the skies opened up and it poured rain.

I leveled my strut from slightly prop-down back to zero degrees and set it's bottom even with the bottom of the sponsons. I also replaced the stock strut bushings with the Octura lead/Teflon bushings. I had to shorten the rear one a bit to make it even with the strut.

I installed a new Octura x640 prop that I sharpened, balanced and polished. (I was paranoid about the health risks and did the whole job with a fine hand stone and wet-and-dry paper in a sink full of soapy water.) I got to the lake, installed a set of batteries and put the boat in. When I took off, the difference in the prop really surprised me... I thought it would be pretty close to the stock one (which I had also sharpened/polished/balanced) but it seemed like it added a lot of performance. As a matter of fact, I flipped the boat over backwards just seconds into my first run.

I ran it around as fast as I dared and brought it in to check the ESC and motor temps: 80's (but I wasn't able to do a lot of sustained full-throttle running). On the next two runs I moved the batteries up to attempt to keep the boat on the water. The last run had them sitting an inch ahead of the motor. The boat looked flat or even nose-down in the water but once it got on plane it seemed pretty good. Full throttle still had it wanting to fly. Maybe the lake wasn't as flat as it looked....

My flex shaft looks like it's loosening up some more at the motor end, so I'm not going to run the boat again until I re-solder it or my new one comes in. I also ordered a new collet with a brass insert that's supposed to be a little kinder to the flex shafts. The Teflon liner has continued to stay in place.

I sure am enjoying this boat. It still impresses me with its acceleration, speed and handling. The weekend after next we'll have three of them in the water at once and I'm sure it will be interesting.

Take it easy,
desmobob

[tiqueman]

Your strut bearing comment intrests me more than anything. Octura and aeromarine bushigs fit with room to spare in both ends of the pb strut.... well, unless they changed the seat depth? Did you pull the bushing back out to confirm there wasn't another bushing in there or that it was actually contacting the set?. Sounds like your getting her dialed in well.

[LiPo Power]

Darin
If the flexshaft is installed properly, when the motor is working, spinning, the spirals are screwing down toward the prop so in my opinion the turn of the flexshaft should push the teflon down, not up.
I think the teflon is too loose inside the bras tube in this case.
I had a little of this problem on mine and the issue was corrected by installing short piece od fuel tubing, see picture.
Problem is gone now and this also helps to keep the grease inside of the tube.
Robert

From my experience with these, it could be one of two things... 1) The teflon was too long and the prop thrusting forward is pushing the stub-shaft up against it, pushing it forward in the stuffing tube... or 2), and more likely... The factory teflon they used doesn't fit snugly into the stuffing tube and so the flex cable rubbing against it, with the spirals "screwing" upwards toward the motor, are pushing the teflon up. This can happen especially if you are using some sticky, thick, grease.
You might be able to fix it by fitting a piece of water tubing over the forward end of the stuffing tube. However, if I recall, there isn't a lot of extra material up at that end. Another solution might be to very carefully put a couple of small "dimples" into the forward end to keep the tubing from creeping forward.

I think on mine, which was the very first Production boat, and was received before they fixed the flex cable rotation issue, I had replaced my cable with an Octura, and replaced the liner as well. I had to so some "stretching" of the Octura teflon to get it to fit, but it's in there now and doesn't move. I also think it's a little more "slippery" than the stock stuff... which is more like a hard nylon tubing than teflon...

[desmobob]

Your strut bearing comment intrests me more than anything. Octura and aeromarine bushigs fit with room to spare in both ends of the pb strut.... well, unless they changed the seat depth? Did you pull the bushing back out to confirm there wasn't another bushing in there or that it was actually contacting the set?. Sounds like your getting her dialed in well.

They must have changed the seating depth! I took the strut off and very thoroughly cleaned it out with brake cleaner and Q-tips after removing the stock bushings. (The rear bushing would slide out easily but the front one had to be drifted out with some light tapping.) The front bushing fit deep into the strut with room for the lip on that cone-shaped piece that goes between the strut and the tube. The rear bushing was about 2mm or so too long and hung out the back of the strut. I held it with my fingers and ran it across a sanding block until it fit flush.

The bushings had a nice loose sliding fit in the strut and the prop shaft stub had a nice loose sliding fit in the bushings. I greased the outside of the bushings when installing them.

Take it easy,
desmobob

[desmobob]

Darin
If the flexshaft is installed properly, when the motor is working, spinning, the spirals are screwing down toward the prop so in my opinion the turn of the flexshaft should push the teflon down, not up.

That's exactly how I figured it, too. I was very surprised when my Teflon liner was moving UP the shaft and getting ground up by the collet. Whatever was causing it has stopped causing it, but I picked up a spare piece of Teflon tubing just to be safe.

Take it easy,
desmobob

[desmobob]

Your strut bearing comment intrests me more than anything. Octura and aeromarine bushigs fit with room to spare in both ends of the pb strut.... well, unless they changed the seat depth? Did you pull the bushing back out to confirm there wasn't another bushing in there or that it was actually contacting the set?.

They must have changed the seating depth! I took the strut off and very thoroughly cleaned it out with brake cleaner and Q-tips after removing the stock bushings. (The rear bushing would slide out easily but the front one had to be drifted out with some light tapping.) The front bushing fit deep into the strut with room for the lip on that cone-shaped piece that goes between the strut and the tube. The rear bushing was about 2mm or so too long and hung out the back of the strut. I held it with my fingers and ran it across a sanding block until it fit flush.

I'm wondering why ProBoat would have changed the seating depth... maybe it's just that my strut's rear bushing area was not reamed to the correct depth?


Take it easy,
desmobob

[tiqueman]

I'm wondering why ProBoat would have changed the seating depth... maybe it's just that my strut's rear bushing area was not reamed to the correct depth?


Take it easy,
desmobob

Very well could be.