pchuckie

Building my first boat. Its a deep v. Going to use two gr2349 min jet drives with speed 500 motors. The size of the boat is 35" long 10" wide. The question I have is, what type of speed control should I use mechanical or electronic. I would kind of like to use one speed control to power both motors. I'm thinking with a mechanical speed control I could use the servo to drive the speed control forward, but hitting reverse I could rig something up when the servo went into brake/reverse it could lower the reversing bucket on the jet drive. With an electronic speed control I think I'd need a three channel radio, the third channel would raise and lower the reverse bucket on the jet drive. Not sure which way to go, any ideas and photos would be greatly appreciated.

sundogz

I'd go with two 29mm drives in a boat that size. And a shallow V hull is preferred with jet drive propulsion. You could use an electronic esc such as a Traxxas and an [link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXMGM3&P=FR]HPI Reverse Mixer[/link] to control the reverse bucket with a 2 channel radio. Just hold the throttle in reverse for 3 seconds and it will flip a servo the other direction. A Traxxas XL5 will power two Speed 500's in parallel.

pchuckie

Thanks for the reply. Any idea where I can source those drives you mention

sundogz

[link=http://www.jet-drive.de/index.php?option=com_virtuemart&page=shop.browse&category_id=4&Itemid=17]KMB [/link] has some 28mm drives available. There was a New Zealand seller on ebay that had some available up until a few weeks ago. [link=http://www.v-eastonline.com/products/JET%252d2-Booster.html]Graupner USA[/link] has some 29mm boosters, you'll need to get the steering/reversing nozzle. [link=http://www.cornwallmodelboats.co.uk/acatalog/graupner_jet.html]Cornwall[/link] might have some available as well. Do you need to have two jets? One 40mm jet would do as well on a boat that size, and the availability is better as Graupner stopped making jet units a while ago.

sundogz

Pchuckie, that person from New Zealand is back on ebay with the 28mm jet drive. [link=http://www.ebay.com/itm/KMB-28mm-Jet-Unit-Reverse-Bucket-/150723190691?pt=Radio_Control_Parts_Accessories&hash=item2317cd5fa3]Here's the link. [/link]

pchuckie

Got the boat finished enough to test it on the water. I used a Novak rooster esc out of one of my old cars to power the two motors. It's pretty slow, I should have opted for the bigger jet drives, but I had already purchased the graupner units. The radio I got was a traxxas 4 channel, I just used one of the channels for the reverse buckets, the fourth channel is for the bait release. Did I mention I'm going to be using this boat to tow my bait out further than I can cast it, thats why I went jet drive as opposed to props.

To get some more speed I'm going to get some bigger motors and a boat esc. As of right now it produces alot more thrust if I hook the motors straight to the battery. I've set and reset all the endpoint settings and it's still less powerfull throught the esc. I'm running 6 cells nicads, I may even try a 7 cell before I try the bigger motors.

Video http://youtu.be/1NqSLcsrdvg