FINALLY, got to run my Spartan

[Snafujg]

Kevin, in one of your other posts, you mention the death wobble at WOT. I would suggest the double trim tab setup. It helped my boat tremendously. The only time I get the wobble now is if the water is choppy. If it's smooth, my boat sits on top of the water and glides nicely.

I think the death wobble comes from the trim tabs being so high. At high speed, the boat really gets out of the water so I think the original placement is too high. When you lower them down to the holes closer to the bottom, they seem to sit right on top of the water.

[dag-nabit]

Kevin, in one of your other posts, you mention the death wobble at WOT. I would suggest the double trim tab setup. It helped my boat tremendously. The only time I get the wobble now is if the water is choppy. If it's smooth, my boat sits on top of the water and glides nicely.

I think the death wobble comes from the trim tabs being so high. At high speed, the boat really gets out of the water so I think the original placement is too high. When you lower them down to the holes closer to the bottom, they seem to sit right on top of the water.

I have been reading the posts about moving/adding trim tabs and it is something I am considering trying.

Just trying one thing at a time, and also trying to just have some fun running our boats.

I will probably order up a couple sets of tabs to give it a try.

Kevin

[dag-nabit]

A very short video of my Spartan running. Nothing new or spectacular here, just proof it runs.

http://www.youtube.com/watch?v=WU4suaGaYE0

Kevin

[chadrob30]

Is the "vent hole" actually an oil hole? I always put a couple drops of oil in there before and after running lol....hope it's ok by doing that. Oops...

[dag-nabit]

Is the "vent hole" actually an oil hole? I always put a couple drops of oil in there before and after running lol....hope it's ok by doing that. Oops...

Perfectly fine to add a few drops of oil. Some boaters recommend adding a few drops of lightweight oil to the stuffing tube in addition to greasing the flex shaft.

I should clarify, I'm not recommending sealing off the vent hole, just suggesting it as something to try. My mod above, which includes sealing the vent hole, has resulted in having residual grease on the flex drive after a couple consecutive runs.

Kevin

[roadrashracing]

I ran my spartan today witht the new setup and it worked really well.

[dag-nabit]

I ran my spartan today witht the new setup and it worked really well.

Did you have grease residue on the drive line after a couple runs?

Kevin

[roadrashracing]

yep

[dag-nabit]

UPDATE:

So here is a bit of an update from a couple weekends ago. I have commented on some of this in other posts already but here it is....

On my last weekend off my Daughter and I had the opportunity to get in several runs with the Spartans, and our other boats. We had a blast, but it was an eventful weekend of running.

This was the first time my daughter ran her Spartan, and she was pretty excited, not more than a minute into her first run the drive cable snapped. We are running aftermarket .150 cables from Jeff, and the liners are changed out to Octura. I also modified the stuffing tubes as described above.

The cable snapped just .5 inch away from the stub shaft. not sure what caused it to fail, but fortunately the cable splayed enough to get tight in the liner and we didn't lose the prop. There was no sign of overheating and the liner was not damaged.

Slipped in the Traxxas OEM cable and we were off and running.

A few minutes later my Spartan died mid run. (of course about as far away from me as possible. I waded out to retrieve it while my daughter took great joy in trying to spray me with her rooster tail.

Turned out the negative wire on my Eagle Tree let loose. Bad solder from the factory. I thought the Eagle Tree was fried because the plastic wrap was melted and it was all black underneath. I soldered it back together a couple days ago and fortunately it seems to be still working. But we were without it for the weekend, so no data graphs for you this round.

A few runs later we had a little side swipe collision, We were coming toward each other with good room to pass by, I was at pretty much WOT and the boat took a pretty good sideways hop and I couldn't correct in time. It didn't appear to be much of a hit (sorry no video) but my turn fin caught her hull and sliced it open like a razor blade. (I had sharpened the edges on the turn fins)

The hull is cut clean through between the red marks, just as clean as if done with a razor.


I didn't have the correct glue with me for a repair, so she ran the Fightercat for a few runs.

After several more good runs I broke the drive cable in my Spartan. Running the same setup as in my daughters boat, but my cable snapped right near the collet end.

There was evidence of overheating on both the stuffing tube and flex cable with both showing discoloration. The liner was destroyed at the point the cable failed. The stuffing tube did not get hot enough to melt the plastic on the component tray.

Again I was fortunate not to lose the prop. Although the stub shaft came out far enough for the prop to contact the rudder and gouge it a bit.

This of course raises the whole chicken or egg question; which came first, did the cable start to fail, bind, over heat, and then completely fail, or; was the drive line dragging causing enough friction to overheat and cause the cable to fail?? There was no prior evidence of drive line heating, and it failed in the straight part of the stuffing tube, not at the bend.

You can see the discoloration on the stuffing in this photo


Failed cable is also discolored


Damage to liner, the pile of "stuff" is failed liner material, it would pretty much turn to powder if rolled between your fingers.


Damage to Rudder


Despite the set backs we had a ton of fun, we both like our Spartans (when they run they are a blast) and if they can hang in reliably for a couple seasons I will be OK with the coin I had to drop into them to make them work.

All the other mods are working great, good water flow from the trim tab pick up, grease residual on the flex drive after running with the longer stuffing tube, Tacon motor seems good so far, lvc on T180 seems a bit quirky but watching it to see what is happening.

Everything is repaired and ready to run this coming weekend if the weather co-operates.

Kevin

[dag-nabit]

TURN FINS STRICTLY COSMETIC??

After the collision with my daughters boat, one of the screws on my turn fin was pulled out and the threads stripped.

I took the turn fins off and took the boat for a short run. It seems to handle and turn fine without the turn fins.

I haven't run it enough to form a definitive opinion on the handling characteristics without the turn fins (especially high speed turns) but the initial indication I'm seeing is that the turn fins are ineffective on this hull and pretty much cosmetic only.

I hope to get in some good runs this weekend and will update after I have a chance to further evaluate the handling sans fins.

Kevin

[bdp1174]

Hey Kevin what type of glue do you recommend on abs plastic for hull repairs and for gluing the seam between the top and bottom hull pieces?

[dag-nabit]

Hey Kevin what type of glue do you recommend on abs plastic for hull repairs and for gluing the seam between the top and bottom hull pieces?

Most glues that work well on ABS actually fuse the parts together by chemically "dissolving" the plastic together. Most glues that work well on ABS will contain toluene or acetone, although there are a couple other chemicals used that also work.

This works well if the parts mate together well, as was the case with my repair. I just used good old Testors plastic model cement and let it dry overnight. If possible clamp the parts firmly together until the glue sets. The shape of the hull doesn't always facilitate easy clamping, On this particular repair I used a piece of lightweight mechanics wire wrapped around the hull and then just twisted the ends with pliers to tighten it enough to cinch the halves of the split tightly together.

I have seen a couple other products recommended here (I think there is a thread on it) but availability of "designer" adhesives isn't great where I live. So I went with what was readily available.

If you have a gap between the parts that require repair, then you need to source a product that has gap filling ability.

Kevin

EDIT: Here is the thread on adhesives: http://forums.offshoreelectrics.com/...ad.php?t=25560

[roadrashracing]

Have you solved your grease exit problem yet? I blocked the whole in my strut with some jb weld, I ran two packs today with that setup, no grease mess and a nice coating on the flexshaft yet.

[dag-nabit]

Have you solved your grease exit problem yet? I blocked the whole in my strut with some jb weld, I ran two packs today with that setup, no grease mess and a nice coating on the flexshaft yet.

Yes, with the extended stuffing tube, and the hole plugged in the strut, I have a decent coating of grease left on the flex shaft after two, back to back, runs.

The silicone plug came out of the hole on my daughters strut and the flex shaft on her boat was pretty much completely dry after one run.

Going to have to find a more permanent way to plug the hole.

Kevin

[dag-nabit]

Crappy weekend at the lake for running RC. Cold, wet and windy all weekend.

Only got one run in with the Spartans.

Mine was handling well with the turn fins removed, and got a quick video of my daughter running hers in rough water.

http://www.youtube.com/watch?v=jfZRhlHR2fk

Kevin