G+_Steve Prior Posted July 26, 2015 Share Posted July 26, 2015 My KH250 build just passed the smoke test! Link to comment Share on other sites More sharing options...
G+_Sean Eno Posted July 26, 2015 Share Posted July 26, 2015 Great job! Link to comment Share on other sites More sharing options...
G+_Oliver Jackson Posted July 26, 2015 Share Posted July 26, 2015 Most challenging part of the build so far? Just wondering as I'm undertaking it soon. Thanks. Link to comment Share on other sites More sharing options...
G+_Steve Prior Posted July 27, 2015 Author Share Posted July 27, 2015 It turns out that tinning wire and soldering bullet connectors isn't my favorite thing to do. Since the KH instructions have us cut the motor leads out of the ESC shorter I ended up using those pieces to make the power distribution board and didn't touch the 1 meter of red and black wire at all - saved me the bother of tinning one end of each wire. I did notice that the holes in the power distribution board are sized for I think 12 gauge wire, so the 16 gauge supplied in the kit doesn't fill the hole so you have to bridge the gap with solder. You also need more bullet connectors than RTFQs.com ships, so order extra, also some more heat shrink tubing, especially in black if you care about getting the colors just so. Also see my post just after this one - two bad bullet connector connections almost convinced me I had two bad ESCs and a would have derailed the build had I not got unexpected debugging skills. Mounting the Flip controller was a little odd - RTFQs.com supplies some nylon pieces for this which are different than how the KH episode does it. I didn't see how to use the supplied pieces, so I ended up using 4 standoffs I bought from a pack on Amazon and had to supply four 12mm M3 screws which weren't in the kit. Then things went great. Today I got in some actual flight tests and that went very well. This quad with a 4S battery flies like a beast compared to the Syma X5. I didn't crash at all, though I did break two props. I finally figured out that of the props flex high enough they hit the top of the frame - not good. So I sanded down the edges of the frame until the props can't reach it, more better. I might also have a defective battery because one cell of the 4S battery seems to discharge much faster than the others. Not looking forward to dealing with that exchange. So there are some minor issues due to the RTFQs.com kit not exactly matching up with the KH podcast instructions, though they are not serious if you buy some extra stuff. RTFQs.com also ships the kit with 2 bladed props instead of the tri-props that KH uses. Maybe because I'm using a 4S battery I get the feeling that the third blade would be a good thing, so I just ordered a few sets from banggood.com. I went all in for the radio on this build and bought a FrSky Taranis Plus - might as well go for it and not want to upgrade later. I also bought the telemetry piece to measure the battery pack condition and report that back to the transmitter - I'm not comfortable with the KH250 kit as is not giving you any battery low warning. I'll also end up adding red/green LEDs like the Syma X5 has so it's easier to see which direction the drone is facing, until then I'll keep the drone much closer so I don't get confused. I'm used to flying the Syma X5 around my front yard after work in the evening, but the KH250 makes a LOT more noise - whiny noise sounds like a mosquito the size of a VW Beetle, might bug the neighbors. Link to comment Share on other sites More sharing options...
G+_Oliver Jackson Posted July 27, 2015 Share Posted July 27, 2015 Steve Prior? Yeah there isn't enough bullet connectors, they provide 12 but in actuality you need 20 pairs due to the nature of the esc two wires going into 3 wires as escs are basically dc to three phase motors. 5*4 =20 it's a little bit of a con if you're going to provide a "complete kit" and you're missing basic things. I went for a different flight controller in the end, the CC3D it seemed much easier to set up and it was basically the same price. I might just not bothered with the bullet connectors and just solder the wires directly, I mean it would make it look a lot nicer imo and there would be less points of failure sure it's not great for when you want to swap the motors or esc due to damage but it's only going to require me to heat up the solder and remove the wires from each other... For the flight controller I opted for the turnigy i6 because it was relatively cheap and well regarded for the price, I would get the taranis but I don't have the money really. $250+ dollars basically in the UK anyway. My parts still need to come I ordered them on the 21st July but they still need to fly across the ocean. I was surprised to see how little shipping was I thought it was going to be an arm and a leg. Once I have mine built I will probably fly it in a large field away from everyone so there is no one to bother. ? EDIT: sorry for my poor punctuation, my English sucks. Link to comment Share on other sites More sharing options...
G+_Nathan Sikita Posted July 28, 2015 Share Posted July 28, 2015 so I have a quick question, I'm new to quad building and the like and just wanted to know if the type of solder you use to connect the wires matters much? Link to comment Share on other sites More sharing options...
G+_Steve Prior Posted July 28, 2015 Author Share Posted July 28, 2015 I'm new to building quads as well, this is my first one, but I've done other DIY stuff. Funny you should mention solder. I've had a spool of pretty thin solder for about 30 years (which I thought might be a lifetime supply) and started using it for this, but found that filling those bullet connectors with solder was burning through it pretty darn quick. So when I ordered the additional bullet connectors I also ordered a small roll of thicker solder. There's electronic type soldering where you're being delicate and then "electrical" type where you're joining bigger stuff. This is the bigger stuff. I'm using tin/lead solder, I don't know whether 60/40 vs 63/37 tin/lead ratios matter. Something around 0.5-0.6mm diameter would be great, I got 0.9mm which was workable, though bigger than I would have liked ( http://www.amazon.com/gp/product/B000G31NWK?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s01 ) . Does this help? Link to comment Share on other sites More sharing options...
G+_Nathan Sikita Posted July 28, 2015 Share Posted July 28, 2015 yeah it does, thanks for the help Link to comment Share on other sites More sharing options...
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