The Unofficial all things Jet drive thread
#4851
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RE: The Unofficial all things Jet drive thread
No worries matey Trim tabs aren't needed on these boats, just move the battery around to balance it and you're away.
#4852
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RE: The Unofficial all things Jet drive thread
ORIGINAL: sundogz
I got more done on the JetCat. Tested it for leaks, were none. The Shoe Goo worked well. On the water cooling, I decided to keep the redundancy and ran two cooling systems. I drilled 2 more holes in the top for discharge (like a jet ski) so I can easily see if each side is cooling. And I patched the original hole in the side. I made a stainless bracket to hold the both esc’s on their sides. This made everything quite tidy, and all cooling lines are short and covered. The bracket is velcro’d to the tunnel, and the esc’s velcro’d to it, so that everything is removable if needed. The motor mount screw holes in the jet needed to be widened and I used a dremel tool to carefully do that. What a P.I.T.A, I should have done that before I installed the jets into the hull! (“note to self…). I drilled a hole in the transom so that I could to easily install/remove the motors using a long hex screwdriver. I used the steering boot hole to do that on the other side. I’ll just cover the hole with hull tape . Drilled another hole! and installed the antenna base with an o-ring seal. The receiver is velcro’d to the transom over the tunnel. The couplers from SicRc made it easy to connect the motors to the drives and everything is smooth and balanced. Now I need to program the esc’s and bench test everything. I will disable one of the esc’s bec by pulling a red wire on the ‘Y’ cable. Don’t want to burn up a bec (thanks, Steve). There’s a lot of room in the sponsons for moving the lipos to adjust the COG – your guess is as good as mine where that will end up being. I plan to use two Turnigy 2200mah 25C lipos unless run time is too short.
I got more done on the JetCat. Tested it for leaks, were none. The Shoe Goo worked well. On the water cooling, I decided to keep the redundancy and ran two cooling systems. I drilled 2 more holes in the top for discharge (like a jet ski) so I can easily see if each side is cooling. And I patched the original hole in the side. I made a stainless bracket to hold the both esc’s on their sides. This made everything quite tidy, and all cooling lines are short and covered. The bracket is velcro’d to the tunnel, and the esc’s velcro’d to it, so that everything is removable if needed. The motor mount screw holes in the jet needed to be widened and I used a dremel tool to carefully do that. What a P.I.T.A, I should have done that before I installed the jets into the hull! (“note to self…). I drilled a hole in the transom so that I could to easily install/remove the motors using a long hex screwdriver. I used the steering boot hole to do that on the other side. I’ll just cover the hole with hull tape . Drilled another hole! and installed the antenna base with an o-ring seal. The receiver is velcro’d to the transom over the tunnel. The couplers from SicRc made it easy to connect the motors to the drives and everything is smooth and balanced. Now I need to program the esc’s and bench test everything. I will disable one of the esc’s bec by pulling a red wire on the ‘Y’ cable. Don’t want to burn up a bec (thanks, Steve). There’s a lot of room in the sponsons for moving the lipos to adjust the COG – your guess is as good as mine where that will end up being. I plan to use two Turnigy 2200mah 25C lipos unless run time is too short.
#4853
RE: The Unofficial all things Jet drive thread
Thanks SkR8Pn. I've tucked the control wires in a shrink wrap package and put it in front of the esc's (over the prior stuffing tube exit) but am looking for something better to cover that mess. Programmed the esc's and everything worked. BOTH of the motors initially ran in reverse, so had to fix that. What luck, maybe not a good day to buy a lotto ticket!. I do have the esc's set for forward/reverse just to see if it can reverse at all (no reverse buckets on NQD drives). That would be nice to help get out of tight places. We'll see. I hope to maiden it this weekend and will post a video.
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RE: The Unofficial all things Jet drive thread
I have a ? for you gentlemen? Now our drought is not quite over but some water in ponds and rivers. Ok, my tear into is ready but need a approx. lay out. I'm using a 2200 3S and Sic esc with a Turnigy 2500kv and I don't use bec but use 4 AA in saddle pack formation. Also to grease the flex shaft on the short end at the rear; what's the best way? I was thinking of turning boat upside down after loosing up set screw and sliding flex shaft toward the motor and putting grease on a piece of bailing and fill the brass hole thru the 1/4" mesh of the pickup. I read both forums on the tear into's and saw not a whole lot . I have some CAR bearing oil by Trinity I could use but would like to hear input on this, oh BTW thanks! When you have time will be fine.
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RE: The Unofficial all things Jet drive thread
Hi Mike, here's a link to some pics to help with your layout, I use the same batt, note that the batt tray is slightly to one side to offset the weight of the ESC.https://www.dropbox.com/sh/qjf05wjcu.../WuJKi1G8LwYou should ideally use a marine grease and do the entire shaft, not just the end where it goes into the stator bush.Any reason you're using a separate battery pack to aower the receiver/servo, you're adding unnecessary weight there if you're ESC has a built in BEC.
#4856
RE: The Unofficial all things Jet drive thread
Most important is to grease the shaft with a good waterproof marine grease such as Pro Boat or Gorilla Snaught. These will stay put longer than bearing oil, and it will prevent cavitation from air leaking out and water leaking in. While it's out, put some on the rear bushing too. You have to remove the stator housing to do that, but get used to it, you'll have to re-apply from time to time. Reassemble and be sure the shaft is all the way back in the bushing when you tighten the coupler. I use silicone to seal it - it is easy to peel off the next time you do it.
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RE: The Unofficial all things Jet drive thread
Hi all just a few pictures of my jet projects, orange daVette still needs lacquer and will be getting the MHZ electric jet when it comes home
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RE: The Unofficial all things Jet drive thread
Thanks,
and yes had blue in water for short time 2-3 min engine cut and club rescued it and took rescue boat out of water, was end of a busy day
Steve
and yes had blue in water for short time 2-3 min engine cut and club rescued it and took rescue boat out of water, was end of a busy day
Steve
#4861
RE: The Unofficial all things Jet drive thread
I finally found time to maiden the JetCat conversion. I apologize for the crappy video. Note limited reverse capability of boat at start of video. 3500kv outrunners on 2S. A few bugs to work out, but all in all am happy with the arrangement.
[youtube]http://www.youtube.com/watch?v=cwqkmU4CAfU[/youtube]
[youtube]http://www.youtube.com/watch?v=cwqkmU4CAfU[/youtube]
#4862
RE: The Unofficial all things Jet drive thread
Another video showing how it heels over in tight turns. The bottom of the sponsons are at a slight 'V' angle which lifts one side a bit and digs in the other. I was a bit worried how that might affect things - that it might slide like an airboat. But it does the opposite. I can't detect any cavitation when one sponson is up, but the motor sound may be masking it.
[youtube]http://www.youtube.com/watch?v=JLo6yT4F1iU[/youtube]
[youtube]http://www.youtube.com/watch?v=JLo6yT4F1iU[/youtube]
#4863
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RE: The Unofficial all things Jet drive thread
Hi all
Finally got orange one back, it looks superb, pictures really don't do it justice, the metal-flake shards change colour with sun light, red, orange, gold, blue, green over a burnt orange candy. The name is a memory of a old friend, means Baby Doll. got it all built up ready for water, will see what tomorrow brings
Finally got orange one back, it looks superb, pictures really don't do it justice, the metal-flake shards change colour with sun light, red, orange, gold, blue, green over a burnt orange candy. The name is a memory of a old friend, means Baby Doll. got it all built up ready for water, will see what tomorrow brings
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RE: The Unofficial all things Jet drive thread
Hi Connerc, the modded jet drives have a brass sleeve inserted into the jet body which supports a flex shaft that the impeller is mounted on. The water pick-up is mounted in the stator housing and the intake has 4 stainless bars to keep the rocks and debris out. Also included is a precision motor coupler made to suit whatever motor shaft you're running. You can see pictures of the mods here :http://www.ebay.com.au/itm/170997743...55.l2649Cheers, Steve.
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RE: The Unofficial all things Jet drive thread
Hi,
Found this thread trying to find info on rc jet drives. I still haven´t seen a jet drive unit i real life except for one I just finished building at home. Impeller is 22mm and I plan on running a 2850kv 380xl on 3s in a DF "Mini Storm" hull. I have no idea if it will work good or what power to expect but I guess one has to start somewhere...
Found this thread trying to find info on rc jet drives. I still haven´t seen a jet drive unit i real life except for one I just finished building at home. Impeller is 22mm and I plan on running a 2850kv 380xl on 3s in a DF "Mini Storm" hull. I have no idea if it will work good or what power to expect but I guess one has to start somewhere...
#4867
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RE: The Unofficial all things Jet drive thread
Hi Guy's, just thought i'd add a project i have been working on for some time,
I will be in production soon to make 1/6 scale Jetsprints, i have been designing my own Jet unit of which have a 30mm Alloy impeller, trimmable nozzel, i am doing a run of 300 jet units , pricing will be determined once i get all the costs back.
As for the hulls they will be Vac formed abs plastic, and i will be supplying 2 different huill designd, a 650mm Long Jetsprint, and a 800MM long Marathon river race jet boat. Both hulls will have hatches and rollcages, dummy drivers.
I have attached a few photo's of the 3d print of the jet unit inlet, still got a few things to change on it before i go into production of them but essentially it will be the same./
Regards Mick
I will be in production soon to make 1/6 scale Jetsprints, i have been designing my own Jet unit of which have a 30mm Alloy impeller, trimmable nozzel, i am doing a run of 300 jet units , pricing will be determined once i get all the costs back.
As for the hulls they will be Vac formed abs plastic, and i will be supplying 2 different huill designd, a 650mm Long Jetsprint, and a 800MM long Marathon river race jet boat. Both hulls will have hatches and rollcages, dummy drivers.
I have attached a few photo's of the 3d print of the jet unit inlet, still got a few things to change on it before i go into production of them but essentially it will be the same./
Regards Mick
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RE: The Unofficial all things Jet drive thread
Hi Mick,
I was planning to do a similar thing back about 5 years ago.
I designed and built my own circuitboard in the end- http://grael-minifactory.blogspot.co.nz/
After doing the development in the above blog I did other things over the last 4 years including RC gliders and building my own surfski.
http://www.blueheronkayaks.com/phpBB...php?f=3&t=2334
Back on the project now, got it doing circle and line movements on the X Y axis but I need more speed, the M6 threads don't move the build platform fast enough. I have a bunch of parts on order to convert the mechanics to Rostock, then I'll modify my firmware to run the three axis in that configuration.
Are you printing in ABS or PLA? Heated build plate ?
Looks like the print needs some dremmel finishing before the mould stage.
I noticed your deck attachment bolt positions are sunk into the plastic, could be a lighter build if you widen the mounting flange out slightly.
What diameter is your print nozzle ?
Graham
I was planning to do a similar thing back about 5 years ago.
I designed and built my own circuitboard in the end- http://grael-minifactory.blogspot.co.nz/
After doing the development in the above blog I did other things over the last 4 years including RC gliders and building my own surfski.
http://www.blueheronkayaks.com/phpBB...php?f=3&t=2334
Back on the project now, got it doing circle and line movements on the X Y axis but I need more speed, the M6 threads don't move the build platform fast enough. I have a bunch of parts on order to convert the mechanics to Rostock, then I'll modify my firmware to run the three axis in that configuration.
Are you printing in ABS or PLA? Heated build plate ?
Looks like the print needs some dremmel finishing before the mould stage.
I noticed your deck attachment bolt positions are sunk into the plastic, could be a lighter build if you widen the mounting flange out slightly.
What diameter is your print nozzle ?
Graham
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RE: The Unofficial all things Jet drive thread
ORIGINAL: sundogz
Have you had any reservations about the P16 being a stepped hull? This is just speculation, but are you concerned that the froth caused by the stepped hull might induce aeration at high speeds? It's for this reason that I looked so long for a non-stepped hull to use for a jet conversion.
ORIGINAL: SicRC
My only concern about building my twin KMB 28 powered PX16 is what's gonna happen when one jet gets a gob full of air and loses thrust.
My only concern about building my twin KMB 28 powered PX16 is what's gonna happen when one jet gets a gob full of air and loses thrust.
http://www.youtube.com/watch?v=rEj1ainByTs
:-)
Nothing wrong with a stepped hull jetboat...
I stopped designing them after that one, it did all I wanted and more.
#4870
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RE: The Unofficial all things Jet drive thread
Hi grael,
mate this 3d print is only to prove the drawings, i have actually paid for the injetion molds to make the units, they will be in ABS , but the impellers will be Alloy or Stainless, i am working on them to be Stainless more than Alloy though.
As for the hulls they will not have steps , but will be a more scale like the actual Jetsprints/ marathon river race hulls. I have purchased a CNC Router to make the mold to Vacuum form the hulls out of polycarbonate or ABS. The hulls and jet units will be sold as a kit, you will have to put them together. I am working on selling along with the kits various sticker kits of a few jetsprint race teams like XXX or True Blue.
Please keep looking as i will be printing the whole jet unit up first to get an actual look them before i release the to the molders.
Nice to see you back on the forum mate, lets see if people like Sundogz visits???
cheers Mick
mate this 3d print is only to prove the drawings, i have actually paid for the injetion molds to make the units, they will be in ABS , but the impellers will be Alloy or Stainless, i am working on them to be Stainless more than Alloy though.
As for the hulls they will not have steps , but will be a more scale like the actual Jetsprints/ marathon river race hulls. I have purchased a CNC Router to make the mold to Vacuum form the hulls out of polycarbonate or ABS. The hulls and jet units will be sold as a kit, you will have to put them together. I am working on selling along with the kits various sticker kits of a few jetsprint race teams like XXX or True Blue.
Please keep looking as i will be printing the whole jet unit up first to get an actual look them before i release the to the molders.
Nice to see you back on the forum mate, lets see if people like Sundogz visits???
cheers Mick
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RE: The Unofficial all things Jet drive thread
Look like you've been putting a bit of spare $ into the project!
These sort of things (modern 3D printers) are pushing a world revolution in fast conception to manufacture.
For lower quantity production you might want to consider 3D printing PLA moulds to produce silicon rubber moulds with, then use those for polyurethane resin plastic final pieces. Got to include risers and sprues for resin inflow and air outflow, if you vacuum the mixed resin before pouring you can get some very nice parts out.
I'm experimenting with various design tools at the moment. Having some programming experience, I'm really liking the look of "openscad".
Working on a minimal budget at the moment, also doing a first revision redesign of my circuitboard, I'm looking to put more axis on board for multi product extruding, if you youtube "rostock and richrap" you'll see what I mean, multicolour prints.
Good luck with the jet unit production... I'm not so sure there's a big enough market for them but this thread and others on the forum have shown that RC jet boats are certainly being adopted by a lot more people. I still remember a local shop owner arguing with me that small Jet boats were not possible, that if it could be done somone would have already done it... Just the sort of person I enjoy proving wrong, wrong wrong!
These sort of things (modern 3D printers) are pushing a world revolution in fast conception to manufacture.
For lower quantity production you might want to consider 3D printing PLA moulds to produce silicon rubber moulds with, then use those for polyurethane resin plastic final pieces. Got to include risers and sprues for resin inflow and air outflow, if you vacuum the mixed resin before pouring you can get some very nice parts out.
I'm experimenting with various design tools at the moment. Having some programming experience, I'm really liking the look of "openscad".
Working on a minimal budget at the moment, also doing a first revision redesign of my circuitboard, I'm looking to put more axis on board for multi product extruding, if you youtube "rostock and richrap" you'll see what I mean, multicolour prints.
Good luck with the jet unit production... I'm not so sure there's a big enough market for them but this thread and others on the forum have shown that RC jet boats are certainly being adopted by a lot more people. I still remember a local shop owner arguing with me that small Jet boats were not possible, that if it could be done somone would have already done it... Just the sort of person I enjoy proving wrong, wrong wrong!
#4872
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RE: The Unofficial all things Jet drive thread
ORIGINAL: grael
Look like you've been putting a bit of spare $ into the project!
These sort of things (modern 3D printers) are pushing a world revolution in fast conception to manufacture.
For lower quantity production you might want to consider 3D printing PLA moulds to produce silicon rubber moulds with, then use those for polyurethane resin plastic final pieces. Got to include risers and sprues for resin inflow and air outflow, if you vacuum the mixed resin before pouring you can get some very nice parts out.
I'm experimenting with various design tools at the moment. Having some programming experience, I'm really liking the look of "openscad".
Working on a minimal budget at the moment, also doing a first revision redesign of my circuitboard, I'm looking to put more axis on board for multi product extruding, if you youtube "rostock and richrap" you'll see what I mean, multicolour prints.
Good luck with the jet unit production... I'm not so sure there's a big enough market for them but this thread and others on the forum have shown that RC jet boats are certainly being adopted by a lot more people. I still remember a local shop owner arguing with me that small Jet boats were not possible, that if it could be done somone would have already done it... Just the sort of person I enjoy proving wrong, wrong wrong!
Look like you've been putting a bit of spare $ into the project!
These sort of things (modern 3D printers) are pushing a world revolution in fast conception to manufacture.
For lower quantity production you might want to consider 3D printing PLA moulds to produce silicon rubber moulds with, then use those for polyurethane resin plastic final pieces. Got to include risers and sprues for resin inflow and air outflow, if you vacuum the mixed resin before pouring you can get some very nice parts out.
I'm experimenting with various design tools at the moment. Having some programming experience, I'm really liking the look of "openscad".
Working on a minimal budget at the moment, also doing a first revision redesign of my circuitboard, I'm looking to put more axis on board for multi product extruding, if you youtube "rostock and richrap" you'll see what I mean, multicolour prints.
Good luck with the jet unit production... I'm not so sure there's a big enough market for them but this thread and others on the forum have shown that RC jet boats are certainly being adopted by a lot more people. I still remember a local shop owner arguing with me that small Jet boats were not possible, that if it could be done somone would have already done it... Just the sort of person I enjoy proving wrong, wrong wrong!
Hi Grael,
I did think of doing them another way but just thought they woulf not be nearly as good as injection molding them, after all i sold my business to get this all going, dont worry though as i was going to be making RC car bodies , other rc boats using infusion process ( hulls up to the 92" mark) , also helping production in water ski's.
The printer i got is a CUBEX, not nearly as expensive as it's counterparts and it has a print area of 240mm x 240mm x 180mm.
Also got a 3d Scanner , Solidworks CAD program, Vacuum former. Yes a few $$ there.
I will be doing a larger Jet to suit a 1/4 Conley V8 too, but that may be a little while off yet.
I will keep posting pics of the little jets as the news comes.
Cheers Mick
#4873
RE: The Unofficial all things Jet drive thread
Mickie, I like the concept of a short bodied jet drive. You probably should soften the intake ramp transition. Eliminate the hard angle entirely and make it a smooth transition into the intake chamber. See arrow.
Grael, no, I haven't forgotten that project! But as I remember it, the whole hull bottom was a series of steps. And no 'unstepped' control hull to compare it to. I am still unconvinced there isn't some tradeoff or losses involved. But then, I have a hard head at times! Good to see you're still lurking.
Grael, no, I haven't forgotten that project! But as I remember it, the whole hull bottom was a series of steps. And no 'unstepped' control hull to compare it to. I am still unconvinced there isn't some tradeoff or losses involved. But then, I have a hard head at times! Good to see you're still lurking.
#4874
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RE: The Unofficial all things Jet drive thread
ORIGINAL: sundogz
Mickie, I like the concept of a short bodied jet drive. You probably should soften the intake ramp transition. Eliminate the hard angle entirely and make it a smooth transition into the intake chamber. See arrow.
Grael, no, I haven't forgotten that project! But as I remember it, the whole hull bottom was a series of steps. And no 'unstepped' control hull to compare it to. I am still unconvinced there isn't some tradeoff or losses involved. But then, I have a hard head at times! Good to see you're still lurking.
Mickie, I like the concept of a short bodied jet drive. You probably should soften the intake ramp transition. Eliminate the hard angle entirely and make it a smooth transition into the intake chamber. See arrow.
Grael, no, I haven't forgotten that project! But as I remember it, the whole hull bottom was a series of steps. And no 'unstepped' control hull to compare it to. I am still unconvinced there isn't some tradeoff or losses involved. But then, I have a hard head at times! Good to see you're still lurking.
I have actually redone the whole inlet and the opening is now 15mm longer and as such have made a better flow, also modified the shaft support so be beafier..
The whole design should be finalised later on this week.
Regards Mick
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RE: The Unofficial all things Jet drive thread
Mickie-
I had an electronics and software business for 4 years.. my dream job! Mine came unstuck with too much time in the same house as the ex wife.
Hopefully you have some marketing deals ready to go, without that it's hard to get volume.
Make sure to chase any other opportunities to use that 3D printing kit to generate $$$
I had an electronics and software business for 4 years.. my dream job! Mine came unstuck with too much time in the same house as the ex wife.
Hopefully you have some marketing deals ready to go, without that it's hard to get volume.
Make sure to chase any other opportunities to use that 3D printing kit to generate $$$