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ohh hell this is gonna be fun 
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lol I hope you got 8mmComment
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Update.
I received a set of ABC 1816 props from Dasboata as well as a set of SMC SRD-V3 Speedrun 6S 5300mAh packs.
I tried the new packs with the ABC 1814(3) props which I have been running on this rig. That combo did not work well. These packs have some serious punch, waaaaaay more than the Zeee's. It didn't seem to like the 3 blade props, it was lifting the back end out of the water and skipping. Some tuning required here perhaps, maybe some more weight needed.. not sure yet. I decided to give the SMC packs a go with the new ABC 1816 2 blade props from Dasboata, before messing with any tuning. This combo worked quite well, had some skipping at first but learned to be more gradual on the throttle and once she plants and bites, she goes good.
It hit 102mph on two back to back passes. And this was with a serious mishap on both runs... I seemed to have made the water pick-ups a little too aggressive (see above posts for a photo of them). At these speeds, it blew the tubing off the pick up tubes both runs... the boat very quickly filled with water during the runs. Not good. So basically I was doing a tractor pull, the boat was getting heavier by the inch, with no cooling to boot lol. Got lucky that nothing was damaged.
I had the silicone tubing ty-wrapped onto the pick up's which are made out of 7/32" brass tubing with slight notching cut into them to act as barbs. I can't secure them much better than that, aside from using adhesive. I have decided I have to re-work the pick-ups. Going to downsize the tubing from 7/32" to 3/16" and cut less aggressive teardrops. Curious to see how much speed was lost from taking on all that water, plus will be less drag with smaller pick-ups. Stayed tuned...
Last edited by mmars89; 08-22-2023, 04:16 PM.Comment
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wow thats insanely fast!
a good way to flare tubing is with the harbor freight center punch set.Comment
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She's got a little more in her I think! Those SMC packs are incredible.
I did think about flaring the pick-up tubes, I have punch sets and a brake line flare tool kit that would work. I think I just oversized them though. My thought process was maximizing flow for the best cooling possible obviously, but at those speeds the pressures are just too great from those big pick-up's, much more than needed. I'm thinking 3/16" tubing with much smaller teardrops will be the way to go. Less drag also. I am also toying with the idea of going with 6v pumps and 3/16" pickups with no teardrops for even less drag. With that, I would run an external receiver battery pack which would be beneficial to not pull power from one of the ESC's BEC. Furthermore, if I'm right about needing a bit more weight in the boat, this would help with that as well. The pump set-up does make sense to me for a boat like this, going from a stand still to flat out pull and back to a stand still.Comment
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UPDATE:
Cooling line blow out issue fixed by downsizing water pick-ups to 3/16" and putting a flare in the brass tubes using a brake line flaring tool so the silicon tubing has something more substantial to bite on. Worked on more tuning and tested many different props. So far my PB is 107mph. Will continue to extract more speed. There is room to prop up a bit, and I have not pre-heated LiPo's yet.
SeaKing 180A V3 ESC's
Leopard 4074 2200kv 2Y Motors
SMC SRD V3 5300mAh 6s LiPo's
1816-17-45(2) Props by Dasboata
-1.2* Trim on drives
CG at 32-33%
Thanks!Comment
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I've made flares for solid cooling tubes with a small collar of the next sized brass tube glued onver the end to build up a shoulder. I've seen member Otto make barbs on his hard line cooling tubes by dipping the ends in epoxy to build up a rim. Just last weekend I had a similar issue with my Bulgarian cat at the Mini Shootout. 100mph+ speeds were blowing my oversized silicone hoses right off my carbon hard lines. I had previously been using only a single zip tie. I smeared a light coating of clear silicone caulk over the tube, reinstalled the silicone lines, then used 3 zip ties. They held up to multiple long 110mph+ passes after that without issue.Vac-U-Tug Jr (13mph)Comment
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Those are all great ideas, thanks for sharing! I like how BUMBLESPECIMOODA used a small piece of silicon tubing as a form and built up barbs with epoxy mud. Will be doing this on my next build.Comment
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UPDATE:
Was able to hit 115mph with LiPo's pre-heated to 90F and 1816-17-45(2) props from Dasboata. But of course, I did not get this on video (GoPro battery decided to fail).
Went out a couple times after with the camera rolling and hit 112mph, she must be camera shy lol Hopefully can get out again before the end of the season and get a 115 or better on video.
Quite impressed with the "budget" electronics I used for this build, was not expecting to break 110.
Cheers!Comment
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nice run!Vac-U-Tug Jr (13mph)Comment
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UPDATE:
Hit a new PB of 117mph. Not the prettiest run, bad driving and bad line, but hit a good speed. I'm thinking 120mph is in reach with current set-up. Probably won't get it out again this season, lakes will be frozen pretty soon in Alberta. But it's on like donkey kong for next season!
Cheers!Comment
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Also, does anyone know the speed "record" for this hull? In any configuration, sanctioned/official or not. Just curious!Comment
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