Ouch!

[mikiek]

Well this has to be some sort of record. Not one to be proud of :mad:

Got my Zelos on Tuesday. It's up for major hull repair today. Scraped a wall while rounding a pond. I'm pretty surprised at the amount of damage. Also kinda surprised not to see some glass at the joint. Looks like the deck is just glued to the hull. I would have expected a little more reinforcement.

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Looks like it wants to separate at the stern as well

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Thinking about trying to get some epoxy in the crack then clamp it. Follow up with clearcoating some epoxy over the crack. Part of the biz I guess. :sad:

[vinnyp]

I'll 2nd that ouch comment!!

[mikiek]

One suggestion for you Vinny. Start slow :crying:

[fweasel]

Dayum. Sorry to see it. I fixed a crack in the seam exactly like that on my Impulse 31 last month, and a crack in my Voracity transom just tonight. I closed the crack with CA, then reinforced the joint from the inside with finishing resin mixed with chopped carbon fibers. Had I to do it all over again, instead of using the thin CA, I would use medium thickness to keep the mess down and hit it with an accelerator. The repair on the inside is pretty easy. Use PT-40 resin, warm it up in the microwave, mix in some chopped fibers, stir it up, and pout it down the inside of the hull along the damaged area. Prop the boat up to keep it from running and let it set in place overnight.

I swung a turn wide with my Zelos on one of the first runs, but fortunately it was a muddy shore and no damage. I also launched it up a rocky embankment, so I got that covered too.

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[mikiek]

It was my stupidity for even being in that pond with the Zelos :frusty: It's nice for the sailboats but too small for anything fast. Plus the hard edge all the way around. The cool thing is it's at work so we go out at lunch and do some RCing.

Man what did you use to get the resin up inside the hull? There's a pool noodle stuffed in there, I'll have to get that out first.

I'm still thinking about a layer or two of something on the outside. If anything, just to seal it up. I've been using WEST system epoxy on my sailboats, I can mix that thin and let it settle into the crack. It's going to look like poop but it should still be usable.

[mikiek]

Well phase 1 & 2 of the repair are complete. Per fweasel, I used some medium CA applied from the outside mainly just to hold the deck to the hull. I sanded down the joint a bit, I went thru the gelcoat but it looks better than when the gelcoat was cracked & chipped. Next I needed to epoxy the inside - no small feat. From the hatch it's about 10" towards the bow to the far end of the crack. My hand certainly doesn't reach that far. Guess I should have borrowed a kid.

The brushes I use for epoxy are those flux brushes - a metal tube with bristles on one end. So I got a dowel and jammed it in the other end giving me a handle about 12" long. Slipping all that into the hull wasn't easy so I unfastened the electronics tray and pushed all that to the other side - hope I can put all that back together. Then I did quite a few dry runs, getting the brush inside the hull and all the way to the bow without touching the bristles on anything.

My plan was to run a fillet along the joint of the deck and hull. I used a trick I learned from my sailboat build. The base WEST system epoxy is fairly runny - about like honey. I added some phenol thickener until the mixture was just barely runny. Then I took globs of that on the brush and slathered it all over the inside joint - front to back. When that was done I set the boat just about upside down, the side with the cracked edge a little lower than the other side. The idea is, before the epoxy sets gravity will pull it to the lowest spot - into the cracked joint. That's where it will harden.

So the epoxy is curing, in the morning I'll figure out how to put a seal on the outside. I also noticed whatever the stuff is that holds the tray mounts to the hull is cracked in several places so I'll be doing some more epoxy work in the hull as well. I apologize for not taking any pictures, but once that epoxy is mixed there's no slowing down.

Jeez, I never thought I would have to be doing this kind of thing on the first week of ownership :blink:

Putzing around these forums (and also fweasel's pix in this thread) it appears that the deck to hull joint is a real weakness in the Pro Boat fleet. Several boats with almost identical cracks as mine. Makes me think if I get another Pro Boat I may go ahead and lay an epoxy fillet in the hull BEFORE I get into more trouble.

[fweasel]

The deck seam can be a weak point on any hull. You did hit a solid wall after all. Two of my electronics tray mounts popped loose after my on-shore excursion and I reattached them with JB Weld.

[mikiek]

I found more damage this morning. A battery came loose at impact. It had moved off the tray and was up against a motor. The motor got turned to such an angle that the flex cable sheared off at the coupler. Had to get the piece of shaft out of the coupler - couldn't do that with the motor in the hull so I pulled the motor. Getting those mounting screws back in is going to be a bear. The other shaft looks a little expanded in the small area where you can see it exit the coupler. I may replace that one as well.

People laugh at me sometimes when I start a new hobby. Besides the main item (bicycle, model, RC boat) I buy every spare part I can find. Tools too. When I ordered the Zelos I also ordered one of every spare part that HH had. Came in handy this time. :w00t: On the bright side, I am getting a thorough tour of the inside of my boat :thumbup1:

[fweasel]

Make sure your flex cables are on the right side and spinning in the correct direction. When looking into the hull, bow forward, the winds in the cables should make a ^ pattern, and NOT a V pattern. The expanded portion of the other shaft is what has me concerned. As far as the motor mounts, ball end allen keys are your friend. Attacht he mount to the motor and snug thos two bolts hand tight then insert the assembly into the hull. The two bolts that hold the mount to the hull are pretty easy to get started, but a long skinny set of needle nose pliers can help. Align everything so the flex cable slips in and out of the collet with no deflection, then tightening it all down. Some thread lock on those threads isn't a bad idea either.

[mikiek]

Since I have a spare cable for each side, I will go ahead and replace the right side as well as the left. It could be OK but at the very least I will pull it and do a closer inspection. I'm considering sharpening the props while I have them off.

I believe I have read a few threads here where someone mentioned shortening the cables. I have no inclination to do that but it did make me wonder HOW it is done. Cutting the cable end of the shaft doesn't seem like a good idea and I don't see how cutting the threaded end would help anything.

I am trying to get the motor back in right now - "easy" huh? I do have some ball ends around somewhere but not sure any as small as that mount screw. One question, for lubing the bearings are you supposed to take the motor housing off or just put some oil on the shaft and let it run down inside?

A good day here for this sort of thing. Too windy to run, however I suppose I could be sailing.

[mikiek]

Oh by the way, the epoxy did just what I wanted. It ran down the side hull and underside of the deck right into the hull/deck joint. There's a decent fillet there now and it's hard as a rock. It ain't gonna break there again :thumbup: If I could get a camera in there I would have snapped a few pix. I put a first coat of paint along the crack and sanded that down. I think I'll tape off that section and use an airbrush for the next coat. My paint mix is not a perfect match but I can live with it.

[fweasel]

A set of metric ball end hex drivers are essential tools for this side of the hobby, especially on a boat with twin motors tucked down in the sponsons. No need to cut cables. You pull slack out anyway when you set the gap between the strut and drive dog anyway. On the stock motors, you can only access the front bearing, sort of. Like you mentioned, oil att he base of the spindle and let it work its way in. The rear bearing can only be oiled by removing the rear cap on the motor while its out of the boat. I do it, but only on the rare occasion that the motors get submerged.

Glad to hear the epoxy work is wrapped up. The funny thing about battle scars, is you're a little less worried about the small scrapes and scratches afterwards.

[mikiek]

A lot of scrapes & scratches today. I feel like I should post a pic of the boat - all back together. Thru sort of a comedy of errors I ended up with most of the insides on the floor of the garage this afternoon. Left motor, removed to get the bit of flex shaft out of the coupler. Right motor, removed to try to get stuff tube out. Right strut, removed cuz the flex shaft would not pass thru.

Replaced left & right flex shafts. Left was damaged during the incident. Right had a few broken strands - not sure how/why. Thank goodness for spare parts - went thru both my spare shafts in less than a week. Ordered more today. Made attempt at balancing/sharpening props.

This was an all day affair. Spent way longer than I expected. Very frustrating at times. Access to some parts was quite difficult. I did find my ball end drivers but even those didn't always help. Will be getting a driver set with a flex shaft. Will also be looking for a box end ratchet for the couplers. I've got to be able to do some of this type work in the field, or maybe at the beach. If you are really supposed to lube the shafts after 20 minutes of runtime I can see at least needing to be able to pull the cables off site. When I go RCing I'm talking hours not minutes.

I'm also frustrated by the amount of damage. Come on, I sideswiped a wall. It wasn't a Dale Earnhart :confused2:

I'll try to mix up some paint tonite. If I have the ambition I'll go ahead and tape off and spray. That would leave the epoxy clear coat for tomorrow.

To make it all worth it, I did a few runs on the lake this evening. The motor is a lot quieter, but the boat seems a little slower. Both probably caused by my prop work. There was maybe a 1/4 ounce of water in the hull afterwards.

[REDLINE1]

I found this testers paint to be a very close match (at least on my Zelos). I found it at the local ace hardware. It's a flat finish (maybe they make it in gloss) so I had to go over it with clear.

[mikiek]

I may give that a try REDLINE. Always nice when you can buy a standard color. The gloss would not be a problem as I will follow up with some epoxy. That puts a nice clear shiny finish on things. I mixed some yellow a little while ago but it's not quite there yet.

The edge of the canopy has become my test surface. It's got several spots where I tried to match.

[mikiek]

I went ahead and taped and painted this evening. I want to get this over with. I'll do a little blending at the edges of the new paint, then clearcoat. Won't be good as new but it should work.

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I noticed that I left the gap at the prop/strut a little bigger than recommended. I've closed it down to 2 mm. The problem is the impeller from the motor moves in and out about 1-2 mm so depending where that is my prop gap can be right on or a little big. I understand about the shaft getting some twist in it when the motor torques it and that the twisting pretty much stops when the drive dog hits the strut. But would someone mind explaining the implications of the gap being too big or too small.

Here's a shot of the right shaft that I happened to notice didn't look quite right. It was definitely about to have a problem. Can't figure out how it happened.
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[fweasel]

That flex cable looks like it was overheated from friction right in front of the collet, or, possibly even slipping in the collet itself. Hard to know for sure without seeing where it falls when inserted.

The gaps at the struts are for the reason you described. The 1-2mm axial play from the motor shaft is normal. Set your gap as the motor spindle sits naturally. I usually leave about the thickness of the cable itself as my guide. You're not really going to ever have too much gap, unless you get ridiculous with it, the only side effect would possibly be uneven wear on strut bearing surfaces and problems with not enough cable in the collet. Not enough gap and the drive dog can bind against the strut when the cable winds up causing friction and increased load on the electrical system. Problems ranging from increased heat and noise or as bad as burnt up motors and ESC's. In the future, I spend money on any more stock flex cables. The upgraded cables from OSE or even the wire drives from Wohlt's are a much higher quality options. They're built better, stronger and run truer.

As for pulling the cables, I use just two 10mm box wrenches, both at the work bench, and in my field box. The water inside the hull may have been a leak between the strut and hull mating surface. I, and others, have cured that by sealing it with a small amount of silicone caulk.

[mikiek]

I definitely have that same leak. I see grease oozing out from behind the strut. I put some sealer on the strut that I had to remove yesterday. I'm gonna put a task down to do the same to the other when I regrease the cable.

Will check out the shaft upgrade for sure.

[Doby]

Your repair looks good..but please keep in mind that there are considerable forces put on a fiberglass hull when it meets a concrete wall..even an sideswipe.
Not the boats fault.

My 42"cat sideswiped another during a race..it opened up his hull very similar to yours...and that was fiberglass on fiberglass.

[mikiek]

You are absolutely right Doby. Complete foolishness on my part even trying to run in that pond. I've thought - maybe when I get better control of the boat. Learn to turn on a dime. But in the end it's still foolishness. Especially when I have a huge expanse of water practically in my backyard.

I'm trying to see the bright side. I have disassembled/reassembled most of the boat. A good learning experience. And you guys have filled me with lots of good information. That's a win.

[Mxkid261]

Repairs look good. Can't get upset at the boat though and think it should be able to kiss a concrete wall. Even if you had reinforcements over the seams it still likely would've cracked. Not much give in concrete.

[mikiek]

Thanks Mxkid261. I will be staying away from anything concrete in the future. This is my first speed boat so I really didn't know what to expect. I am still surprised at the damage but am more than willing to chalk this one off as user error.

Guess I'm just used to RC sailboats which I have done for quite some time. Not a scratch or dent on any of the boats. I'm getting the impression that scratches and dents are to be expected with the speed boats.

Last nite I mixed up some clear epoxy then added a few drops of the Zelos Yellow I mixed up. Painted that just on the cracks and gouges. It was thin enough so that it leveled out very nicely. The big crack almost disappeared. And it's a fair match to the original color.

I think all the taping and painting I did earlier was a waste. The colored epoxy is what I will do from now on. Long live the WEST system :bowdown:

I'll post some pix this evening.

[Mxkid261]

Battle wounds happen lol. You may even see some small cracks here and there in the gelcoat eventually after more use and depending how hard you run it.