Steve Hargreaves - Moderator Posted October 19, 2014 Share Posted October 19, 2014 Shaunie is correct when he says lead free & unleaded don't mix....in a previous life working for a large military connector company we had an issue with some MIL spec connectors that had been tinned in the US (leaded solder) & then terminated in the UK with unleaded solder. The joint was reading a slightly higher resistance than was allowed. We sectioned the joint & discovered (under the microscope) that there was a definite layer between the two types of solder. This was a very high spec set of test equipment though.....in our sheds with our electrical items would it really matter? Probably not.....but nevertheless probably best avoided if you can.... Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted October 19, 2014 Share Posted October 19, 2014 If I'm reading the thread correctly, Simon has a fully working ESC which is specified for the motor/battery/propeller combination but has mechanical damage to one of the PCB tracks on the motor output. The perceived wisdom is to throw it away and replace it with a cheap and cheerful after market job (of which I have used several with no problems). This is "on safety grounds" - but Simon now has to solder 3 connectors with no previous experience. Are we all sure that none of these will end up as dry joints? (No reflection on your practical skills, Simon but good soldering does need a certain amount of skill and practice.) Personally, I would have no qualms in refixing the track and supporting the wiring with epoxy. If it fails subsequently, there's little or no chance of an instant burn out of the BEC part of the ESC so why is it so unthinkable to "risk" a deadstick with an undercarriageless and tough foam motor glider? Edited By Martin Harris on 19/10/2014 22:20:04 Quote Link to comment Share on other sites More sharing options...
Ted Posted October 20, 2014 Share Posted October 20, 2014 Martin, The duff wire is from the battery to input on esc if that goes it's not dead stick because everything will be dead. Ted Quote Link to comment Share on other sites More sharing options...
Peter Beeney Posted October 20, 2014 Share Posted October 20, 2014 Ted, With great respect, but from the photo that certainly looks like one of the 3 motor leads to me, so I’d take Martins handle exactly on how to go about fixing it from Simon’s point of view. Personally I’d just solder it back anyway but I do understand that’s not going to be easy for everyone. If that wire does come adrift the motor will stop but the voltage regulator, and therefore the radio, will still work ok. PB Quote Link to comment Share on other sites More sharing options...
Dave Hopkin Posted October 20, 2014 Share Posted October 20, 2014 The photo is confusing! The Battery leads (at the far end) look like they are wrapped in black insulation tape, the motor leads (closest) are wrapped in clear tape, its the clear tape end (motor leads) that are the subject of this thread - so a failure wouldn't cause a radio power down (unless maybe they shorted) But on the battery side is that a repair too? are the battery input leads totally secure, a fail there would be far more dramatic (as ALL radio would be lost) and having a power leads loose could put a short right across the battery with the high amperage wiring... the resulting conflagration might be very helpful for night flying but not recommended! Quote Link to comment Share on other sites More sharing options...
Simon Hall 2 Posted October 20, 2014 Author Share Posted October 20, 2014 Below is another pic of the ESC, hope this makes things a little clearer. The only thing I did to it after the crash was to tightly wrap some strong clear packing tape around the end where the damage was to hopefully 'hold' things together until I could see whether there was way to repair it. The red terminal which connects to the motor is what took the brunt of the damage. The blue motor terminal seems to have suffered no damage. The strong, thick solder is intact on the red terminal, but with the force of the crash, it has pulled away some of layers of the underlying PCB and made the whole connection very loose, sort of hanging by a thread in a way. The battery end was totally undamaged and the black shrink wrap around this is all standard. Just the clear packing tape is all I have added. I have the Turnigy Plush 40a (Hobbyking) in my basket from a link above, but would really like some help choosing the right connectors for my lipo and motor. A friend of mine will solder, as he knows what he is doing. I think the motor plugs are 3.5mm bullets? Not sure about the other blue connector. Links to all the bits I need will be much appreciated! Excuse the Gorilla Glue grafitti from my first couple of crashes! Edited By Simon Hall 2 on 20/10/2014 18:37:48 Quote Link to comment Share on other sites More sharing options...
Dave Hopkin Posted October 20, 2014 Share Posted October 20, 2014 Your battery is an EC3 type connector - Eflite always use them. The ESC/Motor connectors will be 3mm or 3.5mm Gold Connectors, you will have to measure them to find out which But note the ESC you have ordered does NOT come with any connectors...... Quote Link to comment Share on other sites More sharing options...
Simon Hall 2 Posted October 20, 2014 Author Share Posted October 20, 2014 Posted by Dave Hopkin on 20/10/2014 19:20:37: Your battery is an EC3 type connector - Eflite always use them. The ESC/Motor connectors will be 3mm or 3.5mm Gold Connectors, you will have to measure them to find out which But note the ESC you have ordered does NOT come with any connectors...... I really did not think it would be this difficult to replace the ESC with an aftermarket alternative. I did not have this problem with another cheaper backup Lipo which had compatible connectors. Does Parkzone (Hobbyking?) use some random connectors that no one else uses? I am now thinking of just buying the same Eflite unit to replace it. It's expensive, but measuring a half mil difference on a bullet connectors is beyond me as a total novice as well as the hassles of whether the soldering is good. Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted October 20, 2014 Share Posted October 20, 2014 EC3 connectors here The motor connectors will almost certainly be 3.5mm gold connectors (see here) buy both male & female & in case they don't match your mate can solder new connectors onto the motor as well..... Quote Link to comment Share on other sites More sharing options...
iqon Posted October 20, 2014 Share Posted October 20, 2014 does the E- flite one come with connectors fitted. if so buy that one, if not HK.......if you are going to have to solder you may as well get the cheaper one.....as long as you dont need customer support, thats on backorder.... Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted October 20, 2014 Share Posted October 20, 2014 Ooo almost forgot...you'll need some heatshring tubing too.....to insulate the bullet connectors after you've soldered then to the ESC.....something around 5mm id should do it..... Quote Link to comment Share on other sites More sharing options...
Dave Hopkin Posted October 20, 2014 Share Posted October 20, 2014 Loose heart do not young flying type person..... there is an easy answer... Go to your local £ shop, or B&Q and buy one of these Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted October 20, 2014 Share Posted October 20, 2014 Yep those should handle as much as 10A with ease Dave....unless they melt first..... If the soldering bothers you Simon then perhaps replace like with like & buy another Eflite unit.....this will of course be more expensive. Alternatively buy the HK unit & the connectors & send them to me...I'll solder them on for you.....drop me a PM for my address.... Quote Link to comment Share on other sites More sharing options...
Dave Hopkin Posted October 20, 2014 Share Posted October 20, 2014 Actually they are rated up to 60Amps, the larger sizes anyway.... and when you strip the wires so the bare ends go under both screws then the brass barrel providing very little conductive area anyway. Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted October 20, 2014 Share Posted October 20, 2014 The 60A versions will be about as big as the ESC itself. Unless there is some form of terminal protection then the screw bearing directly onto the conductors will break some of the strands...vibration will break a few more. A very poor idea in my view. Quote Link to comment Share on other sites More sharing options...
Pete B Posted October 20, 2014 Share Posted October 20, 2014 Gotta go with Steve here. I really don't think choc block connectors have a place in any RC model, if only from the aesthetic point of view... Mainly see in Ebay offerings, from what I've seen..... Pete Quote Link to comment Share on other sites More sharing options...
Simon Hall 2 Posted October 21, 2014 Author Share Posted October 21, 2014 Posted by Steve Hargreaves - Moderator on 20/10/2014 19:49:01: EC3 connectors here The motor connectors will almost certainly be 3.5mm gold connectors (see here) buy both male & female & in case they don't match your mate can solder new connectors onto the motor as well..... Thanks, gonna go for these and the heatshrink tubing with the Plush 40A ESC. Thanks for your kind offer of help soldering them, but my friend is pretty handy with this kind of thing, so I will watch how to do a good job and do it myself next time. I am sure there probably will be a next time, so I am going to order some more connectors as spares as they are so cheap! I have another Radian (PnP) on order so the old one will be given to my son to learn with once I am more confident with him after a few more buddy box outings. Quote Link to comment Share on other sites More sharing options...
Pete B Posted October 21, 2014 Share Posted October 21, 2014 If you're ordering from HK UK, you might find you can shop all-in-one.... EC3 x 10prs and 3.5mm bullets. That should keep you in stock for a while... Pete Quote Link to comment Share on other sites More sharing options...
Simon Hall 2 Posted October 21, 2014 Author Share Posted October 21, 2014 I decided to carefully pull off the clear packing tape that I originally put tightly around the damaged Eflite ESC to have a close look and take some better pics for you all to see. The loose red wire came right off! It was hanging off to start with. Now you should clearly be able to see the full extent of the damage from these pics. How it's worked since is beyond me. I have also added some pics of the bullet male/female connections. I can't see any other place for this ESC than the bin looking at it now. Quote Link to comment Share on other sites More sharing options...
Bob Burton Posted October 21, 2014 Share Posted October 21, 2014 As I said earlier in the thread - OUCH ! Mr. bin, meet Mr. ESC Don't forget to cut off the leads before you throw it away. They and their connectors could come in handy in the future. Quote Link to comment Share on other sites More sharing options...
Simon Hall 2 Posted October 21, 2014 Author Share Posted October 21, 2014 Posted by Bob Burton on 21/10/2014 18:22:44: As I said earlier in the thread - OUCH ! Mr. bin, meet Mr. ESC Don't forget to cut off the leads before you throw it away. They and their connectors could come in handy in the future. I was going to say that about the lead connectors but felt silly. Would it be considered a bodge to just snip these nice connections off and solder/shrink wrap them on to the new ESC bare wiring? Edited By Simon Hall 2 on 21/10/2014 18:46:40 Quote Link to comment Share on other sites More sharing options...
Bob Burton Posted October 21, 2014 Share Posted October 21, 2014 By all means rescue the connectors with a view to reusing them but you will be be hard pressed to get the blue EC3 connectors apart. Solder and shrink wrapping the wires is acceptable but adds another point to failure. Quote Link to comment Share on other sites More sharing options...
Peter Beeney Posted October 21, 2014 Share Posted October 21, 2014 I think I might take exactly the opposite view with regard to the choc blocks. I’ve used them quite a lot throughout the years of modelling, mostly I suppose because I’ve always had them to hand. As a mechanical joint they are quite strong, ideal for say connecting two halves of a push rod. Extremely quick to assemble and with easy precision to getting the flying surface exactly where you want it. In this situation you can dispense with the insulation, and if you really want piece of mind use two. They’re cheap and come in a variety of sizes, just use the smallest that will slide over the metal rod. If such a complete push rod were given a strain test, to the point of breaking, I’d bet my house it would be the plastic quick links at the ends that parted company long before the choc block cried enough; and the metal quick links are not always that good either, I’ve noticed on more than one or three occasions a very ill fitting threaded end has allowed the link to slide up and down on the rod! Taking an angle on the electrical qualities, again in terms of general aeromodelling standards, I’d actually also rate them quite highly. One spec. to consider is that the resistance of a join should not be any higher than than the same unit length, (as of the choc block), of the joined conductor, and as it happens I think choc blocks will get somewhere pretty near this. As with the push rod, use the smallest that will take the wires, if the wire will carry the current ok, then so will the connector. If it were getting hot enough to melt the plastic that would be tending to imply that it’s resistance is also fairly high; high enough, perhaps, to have a serious effect on the performance of the motor anyway. As Dave said, the conductors should go right through the block, that’s one way of doing it, alternatively if space etc. allows then it’s possible to twist the copper conductors together and slide in from one end. A check on the robustness might also throw up a few disparities, too. Try connecting a receiver battery to a switch harness with say a four foot piece of wire and a couple of (correctly connected) choc blocks, then drop the battery from five feet so that it snatches up and see how many times the choc blocks let go. Times out of ten. I’ve never done this myself, so I’ve no idea, but I’d very much suspect not many. Now do the same thing again, but using the standard receiver battery plug. Again, I’ve never done this, but I think I can guarantee this plug and socket will definitely let go… ten times out of ten. Thus purely in terms of model safety, I certainly know which connector I would prefer. I’m sure there’s even more milage here, but even on this score I have no qualms whatsoever in using these electrical connectors; but, as always, it’s just a personal choice. And I have to say, I’ve never had even the suspicion of a problem with these things. Simon, For postage costs I’d certainly be willing to have a look to see if it’s repairable. I’m sure it might even be a doddle compared to repairs to indoor models with all the bits torn off those little PCB’s. PB Quote Link to comment Share on other sites More sharing options...
Dave Hopkin Posted October 21, 2014 Share Posted October 21, 2014 I think there is a great deal of "over engineering" of electrical circuitry in the installation side of electric flight, For example, I have here a 4-Max/Purple power PPPO-3548-790, quite a beefy beast rated at 850 Watts for a 60Amp ESC, when I put a Micrometer on the motor wires, they are 1.5mm (presumably multi conductor wires) Now forgive me, but would I wire up a 60Amp Circuit using 1.5mm Wires? According to British Standard 6004 (household wiring) the diameter of flexible cable (multi conductor) for 60Amp is around 15mm Mark and it doesn't change significantly be it DC, 2 Phase AC or 3 Phase AC...... So I remain totally confident that my chocolate block connector will be far less failure prone than home soldered bullet connectors with the potential for dry joints But its a personal choice Quote Link to comment Share on other sites More sharing options...
Pete B Posted October 21, 2014 Share Posted October 21, 2014 That's as may be, Peter, but TBH my approach on this thread to a new modeller has been to encourage an ethic of caution, safety and 'Best Practice', if you like. It's one thing for an experienced modeller to make a judgement on what is a viable repair to damaged equipment but a novice would probably do better to err on the safe side until that knowledge and experience is gained. Pete Quote Link to comment Share on other sites More sharing options...
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