Jim Stevenson

Hi Frank. Thanks for the info, this will go in my bookmarks for future use. Unfortunately it contains the line: "Combine this tiny 1.3gm device with an electric speed controller" so although it will be useful for other things I still need an ESC. Luckily my motor is from eFlight so there is a matching ESC available "off the shelf". I might still need this to allow me to connect a capacitor instead of a battery. Regards Jim

Hi John. I assume that it's forum policy that the forum is not used as a sales platform but if, as I am doing in this case, one member requests that either a third party (Derek Knight) makes contact with me regarding his merchandise, or that someone supplies a contact for the third party to enable the forum member to complete a project, will this break the rules? That was a big lump of legal jargon. Did it work? Regards Jim

OK Guys Have a look at this: **LINK**. Have fun Jim

Dave, This is something I along the lines of what I have in mind. It will need more research but it's a valid learning process. I might have to resort to a battery but we'll never know till I try. However getting the bits together may well take a while so be patient. Regards Jim

Peter, our posts crossed. But take a bow for the info. I like the supercap idea simply for the weight savings and automatic run time limiter. Same ideas the cheap cells really. I have no fixed ideas of how to do this so all ideas welcome. I would even look at beamed power, no battery just a car sized generator and transmitter, but I suspect that could be a way off yet. Keep posting, I can keep learning. Jim

John, I knew I had only a sketchy idea of how the motors worked so I asked for help and clarification and got it. Now I need to work out how to use the info to fit the components into the airframe. Since all of the components are tiny it will not be too difficult. Dave, as you can see I'm not against an ESC. I simply could not see the point in one. Now, with a better understanding of the components and their functions I am happy to work from there. Do you think the Supercap will function as a power supply in place of a battery? Once more Thanks guys Jim

Hi Dave Was doing my research when your post landed. I was confusing the methods of driving the rotor. Looks like you can get circular track DC or AC linear motors but "Brushless" is a different animal, So it seems I need a ESC. It looks like the reason for this is that in larger scale motors the ESC is built into the motor, a bit like the inverter in a car alternator, but when you come down to model aircraft sizes it is larger than the motor and needs to be separate. That clears up the requirements for the motor and the idea of a supercapacitor solves the weight problem so this looks doable. All I need to do now is work out what bits to order then get impatient waiting for them to arrive. I'll also need to build another 162 as the one pictured will not convert to EDF. Still, building them is a major part of the hobby for me. Regards and Thanks Jim

Since the previous post was a bit of a marathon I thought I should show you where I am at the moment with the build. Regards Jim

I seem to have opened a can of worms on this one. But let's start replying to your comments. Phil, I had not thought of a supercap and it sounds like a great idea. It will also be easier to mount inside the airframe. Thanks Dave, The implications from your post is that the brushless motor must be run through a separate set of "electronic" brushes and that the three wires are only to supply power to individual windings to create the continuous movement of the rotor. Please tell me if I am reading your comments correctly. Thank you. John P, You have got it spot on. All I need is a power supply which is ungoverned and as far as I was aware the "extra" wire was to allow the power to the motor to be varied. I realize that I lack the specific knowledge about these motors so I have asked for help and the forum members have responded very well indeed. Your query about linear motors is best answered like this: Take your straight centre conductor and curve it into a circle. Feed it with power and put your vehicle with the other windings over it and it runs in a circle. Move the vehicle to the inside of the circle at 90Deg to the circle and you have your rotor and your stator. Does that make sense? Peter, I was under the impression that ALL electric motors were DC. Traction voltage (trains, trams, etc) is in the I've range and so need regular feeder stations which could be done away with if AC was used with the relevant saving in costs. John O, You are absolutely right. I just hate to buy something then destroy a fully functioning model to get the bits I want. As far as space to fly goes for free flight I can achieve that inside a sports hall have a look at the videos on this page **LINK** It's not what I intend but it shows you the possibilities. Once again thank you guys. Armed with these suggestions I can now ask some more questions of others who may be able to help, but, please keep responding so that I can keep learning. Regards Jim

Great feed back guys! But, What I had intended was to fly this with some Spanish (El Cheapo) cells and accept that they will be defunct at the end of every flight. That way I get gradual run down of power for reasonable landing and the possibility of indoor flight. There is no R/C unit to be fitted so I don't need to split current etc, as the motor will be the only powered unit in the aircraft. I have no idea if the concept will work, or if the cells will actually run the motor, or even if they will damage it! However at the power rating of the motor it will soon suck them dry. So I will hopefully not need a GPS tracker Therefore I do not need a speed controller or cut out (weight saving) or a LiPo battery weighing three or four times more than the rest of the outfit. The wingspan is only 11.5 inches so space is a major problem but, Hey I'm doing this as a challenge. Idid notice the comment that the ESC provides switching as provided by the brushes in a "normal" motor. How certain are you of this as if its a linear motor there should not be any switching simply two emf fields? Soon as I get a handle on this board I'll drop a couple of pictures on but up to press I have not loaded an album up. It even took me three days to find the replies so apologies for the delay. Regards Jim

Not certain which I come under. Many years away from the hobby and previous last build in 1964. Current build is a free Heinkle 162 plan from Mikes Flying Scale Models: **LINK** So it's plan build but not commercial plans and I have no objection to ARTF or RTF. or even paper gliders which you can knock out in half an hour and hand out to Nephews, nieces, grandkids or envious onlookers (Have a look here : **LINK**and ,yes., I DOES fly reasonably well) and all it costs is a couple of sheets of paper. It's not how or what you build. It's the pleasure you get from the building or flying. I can't separate the two so I think of it as a double helping of fun. Regards Jim

Guys I need a bit of help here. A long time ago I got a set of plans for a Free Flight He 162 from " Mikes Flying Scale Models" webpage. The plans are great and the bulk of the build is complete. BUT, the beast is designed for the "Rapier" series of rocket motors and there are continuous problems getting them. This has made me determined to produce a ducted fan version. I'm still going to complete the original and have ideas to make my own rocket motors. However I am now at the stage where I have fabricated a jet pipe and compressor for the EDF and recently got a eflm30180mdfa motor which fits into the engine nacelle on the 162. So far so good. The snag is that I have no idea how to wire it to the battery pack and since this is to be a free flight model I don't even know if it will run without the ESC. Even discovering that it is a 7.4v motor meant looking up the model it is normally used in and seeing what replacement battery pack is sold for it. SO! can anyone tell me how to wire this up, will it run without the ESC or will that harm the motor? I'll drop a pic of the framework onto a post as soon as I have organised an album Thanks in anticipation. Jim