Learner Posted November 3, 2023 Share Posted November 3, 2023 I think the subject of prop clearance was brought up in one of your other build threads, perhaps go through those. Quote Link to comment Share on other sites More sharing options...
toto Posted November 3, 2023 Author Share Posted November 3, 2023 Hi Learner. It was. I'll check it out. I think there was a link to ecalc in there as well. I have time on my side at the moment so I'll get around to that closer to the time. Cheers Toto Quote Link to comment Share on other sites More sharing options...
Piers Bowlan Posted November 3, 2023 Share Posted November 3, 2023 My own take on it is that 4S would be the ‘sweet spot’ using that motor which potentially could give you 700-800W with a suitable prop without frying the motor (hopefully). More than enough but you don’t have to fly it like you stole it, you have a throttle! You could give George Worley of 4Max a ring and ask him for advice on which set up he would recommend. You don’t have to tell him you already have a motor, besides he might recommend another. 😊 At the end of the day to some degree it is about how you want the model to fly. Just check with a Watt meter before you commit aviation that you are in the right ball park. Quote Link to comment Share on other sites More sharing options...
Nigel R Posted November 3, 2023 Share Posted November 3, 2023 17 hours ago, Peter Jenkins said: devils own job to find the slots you've made! It's really not. You can just note down where the slots are on a bit of paper, or on the plan. I much prefer to have all gear and the various rods & linkages in place and working at the earliest point possible, i.e. before going near covering. Horses for courses. Quote Link to comment Share on other sites More sharing options...
Peter Jenkins Posted November 3, 2023 Share Posted November 3, 2023 1 hour ago, Nigel R said: It's really not. You can just note down where the slots are on a bit of paper, or on the plan. I much prefer to have all gear and the various rods & linkages in place and working at the earliest point possible, i.e. before going near covering. Horses for courses. Indeed. Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted November 3, 2023 Share Posted November 3, 2023 (edited) 2 hours ago, Piers Bowlan said: My own take on it is that 4S would be the ‘sweet spot’ using that motor which potentially could give you 700-800W with a suitable prop without frying the motor (hopefully). More than enough but you don’t have to fly it like you stole it, you have a throttle! You could give George Worley of 4Max a ring and ask him for advice on which set up he would recommend. You don’t have to tell him you already have a motor, besides he might recommend another. 😊 At the end of the day to some degree it is about how you want the model to fly. Just check with a Watt meter before you commit aviation that you are in the right ball park. Just out of interest to fill a few spare moments. I've had a look at 4Max's info for the model and they recommend a 400W power train. Sarik give the model's UUW at 5.5lbs, which although based on the IC version shouldn't be too far off the mark for a leccy trainer providing you don't use a monster battery. No going to set any speed records but a good starting point. Based on the above, your 800Kv motor, with a four cell pack driving a 12 inch diameter prop should work. Don't go too coarse on pitch for a trainer - six or seven inches will be ok. Max current is likely to be around 30A at full whack.. Just a paper excercise using the RCplanes calculator which I find is much easier to use than Ecalc and with only a bit of extra basic arithmetic. Quite a few variables and assumptions obviously, but I'd be surprised if the above figures were that far out. Remember, no matter what, your wattmeter is your friend to keep the magic blue smoke at bay. A very tidy and competent build, Toto - the model will be a good one and will be well suited to a bit of tuning to get more performance as you gain experience and try more advanced stuff in the fullness of time. It's a clean design and well suited to all the basic aeros with a few tweaks here and there. Edited November 3, 2023 by Cuban8 2 Quote Link to comment Share on other sites More sharing options...
toto Posted November 3, 2023 Author Share Posted November 3, 2023 Thanks for checking that out Cuban8. As long as I am on the correct path. I'm happy. Seems a big difference between the 400kv and the 800 kv motors though. As I said, my understanding of these calculation HAS to improve going forward otherwise there could be some expensive mistakes made. I'm literally at the reliance of others meanwhile. Toto 1 Quote Link to comment Share on other sites More sharing options...
Peter Jenkins Posted November 3, 2023 Share Posted November 3, 2023 Think of kv as gears in a car. A low kv means that power is generated at lower rpm so the prop goes round more slowly and can therefore, usually, be a larger diameter higher pitch one so equates to a high gear, say 5th or 6th. A high kv means the power is generated at higher rpm so the prop goes round much faster which means a smaller diameter and/or lower pitch, say 1st or 2nd gear. If you find that confusing just ignore my post. 2 Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted November 3, 2023 Share Posted November 3, 2023 Peter is spot on with his analogy and with that in mind one can select a power train suited to a particular application. A manic EDF with a tiny fan needs to rev so high Kv - a Junior 60 that wafts around in an unhurried manner will be nice on a slow turning large prop - low Kv. The tricky bit for those with only a rudimentary knowledge of basic electrical calculations, is getting the current (amps) and hence power (watts) flowing in the system to be within the hardware's specifications and accordingly if incorrect, giving the magic blue smoke a route of escape. It's not at all easy to get right for most people, especially when one throws in such choices as how many cells? What capacity? C rating? Do you want to run fewer cells at a higher current, or more cells at a lower current to get a similar power? How to achieve that? Why does it matter as long as the model flys? A good discussion to get the eyes of IC only die-hards to glaze over........😉 1 Quote Link to comment Share on other sites More sharing options...
toto Posted November 3, 2023 Author Share Posted November 3, 2023 Hi Peter, I won't be ignoring your post that's for sure. I need to get my head around it even if it takes a bit of time. All these comments will eventually hit home in a eureka moment. everybody has their own rate of learning and taking these things in. Unfortunately, I am on the wrong side of 50 and you know what they say about trying to teach an old dog new tricks ..... I get there eventually. As well as being grateful for folks input, I'm equally as grateful for their patience whilst it all sinks in..... at some point. Many thanks Toto 1 Quote Link to comment Share on other sites More sharing options...
Peter Jenkins Posted November 3, 2023 Share Posted November 3, 2023 Don't worry Toto, I was the wrong side of 60 when I started on electrics having been a diesel (teenager) and glow (50+ on) person. It's all very different when msking the change. The difference is that I only went electric after my first few aerobatic competitions. However, not having an IC engine noise to judge power settings I had to find another way of doing so and my JR Tranny could be set so with the throttle stick at the desired opening It emitted a beep. That was very helpful. I'm now well on the wrong side of 70 but still enjoying competing in aerobatic competitions. Quote Link to comment Share on other sites More sharing options...
toto Posted November 3, 2023 Author Share Posted November 3, 2023 Great to hear Peter ..... there's hope for me yet .....😄 Well ..... I hit the shed early tonight ( about an hour so far ) to let me achieve one of my goals .... fitting the motor. I had intended getting wing 2 started but that depends on completing some homework that I've been set ahead of tomorrow's flying session. Setting dual rates on both my NX6 and NX8 transmitters. Anyway .... you can read more on that on my " first taste of the skies " thread if you are interested ..... for now ...... on with the task in hand. First up ..... here is what you get with the motor ..... and the spinner thingy broken down .... So first ... I used the mounting plate to mark the holes on the motor mounting box ...... to mark where I had to drill the fixing holes in the mounting block. and then started building the motor ...... the mounting plate fixed into position with the supplied screws into countersunk holes .... Then to fix the spinner doofer to the other end with the supplied 4 x hex head type screws .... ( machined threads on all ) on with the spinner and doobry washer plate thingy ..... and we are left with this collett which I have been told on previous builds .... erm ..... assemblies that is surplus to requirements .... so its into the spares box with that for now unless advised otherwise. **** Note **** no thread lock used so far ...... Advice welcome .... Then it is bolted to the previously drilled mounting block using hex bolts and Nylock nuts ..... washers are inserted both sides of the mounting block ..... and **** NOTE **** I assembled in such a way as to have the cable that comes from the motor at the correct side to allow the cables from the ESC to feed through the mounting block for connection to the motor ....... after installing it the other way around initially. The hole as can be seen above will need drilled out as there is no way that the three cables will fit through. So .... not much in the way of progress tonight .... BUT .... if I get my transmitters set up for dual rates for tomorrows potential flying session ( which takes priority ) I will be back to start the second wing..... wish me luck cheers for now toto 1 Quote Link to comment Share on other sites More sharing options...
toto Posted November 3, 2023 Author Share Posted November 3, 2023 And ..... off we go again ...... and .... you know how this goes from the previous so I won't put you through that again. I am going to finish here for tonight for two reasons. first .... I need some beer time and my mate John Smith is getting impatient ..... and secondly .... I'm starting to make mistakes. I snapped a wing former that was too tight to fit in ....... but I percevered and it went ...... it went crack !!!! No big issue I can strengthen it once building in permanent as this is my usual dry test fit. I'll show the damage and how I try to fix it later when I come to it. getting too either lazy or careless so its time to stop for the night. Cheers for now .... more from the shed tomorrow night. toto 1 Quote Link to comment Share on other sites More sharing options...
GrumpyGnome Posted November 3, 2023 Share Posted November 3, 2023 Threadlock toto.... 1 Quote Link to comment Share on other sites More sharing options...
toto Posted November 3, 2023 Author Share Posted November 3, 2023 Thanks grumpy, I take it we are referring to the motor installation earlier. I'll catch that this weekend. I'm assuming both the motor mounting cross plate and the bolts that hold the spinner back plate on as well. toto 1 Quote Link to comment Share on other sites More sharing options...
Piers Bowlan Posted November 3, 2023 Share Posted November 3, 2023 Doesn’t the collett go on the motor shaft? Quote Link to comment Share on other sites More sharing options...
toto Posted November 3, 2023 Author Share Posted November 3, 2023 OK .... the last shot for tonight ....... The 2nd wing is progressing .... had enough now ..... toto 2 Quote Link to comment Share on other sites More sharing options...
GrumpyGnome Posted November 4, 2023 Share Posted November 4, 2023 7 hours ago, toto said: Thanks grumpy, I take it we are referring to the motor installation earlier. I'll catch that this weekend. I'm assuming both the motor mounting cross plate and the bolts that hold the spinner back plate on as well. toto Yup. Threadlock for all metal to metal is my SOP. 2 Quote Link to comment Share on other sites More sharing options...
Piers Bowlan Posted November 4, 2023 Share Posted November 4, 2023 Weights with lightening holes. Love it 🤣! Quote Link to comment Share on other sites More sharing options...
Learner Posted November 4, 2023 Share Posted November 4, 2023 9 minutes ago, Piers Bowlan said: Weights with lightening holes. Love it 🤣! You have to pay extra for the air in the holes too!! Quote Link to comment Share on other sites More sharing options...
Piers Bowlan Posted November 4, 2023 Share Posted November 4, 2023 41 minutes ago, Learner said: You have to pay extra for the air in the holes too!! Nothing in life if free, even air! Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted November 4, 2023 Share Posted November 4, 2023 2 hours ago, Piers Bowlan said: Weights with lightening holes. Love it 🤣! Years ago Webbies used to sell sheets of lightening holes, they were bagged up and hung next to the left handed sandpaper on the racks. Those late Friday night openings were a great laugh, but bought a lot of kits, many of which are still in the kit mountain 20 years later. Quote Link to comment Share on other sites More sharing options...
Learner Posted November 4, 2023 Share Posted November 4, 2023 30 minutes ago, leccyflyer said: Years ago Webbies used to sell sheets of lightening holes, they were bagged up and hung next to the left handed sandpaper on the racks. Those late Friday night openings were a great laugh, but bought a lot of kits, many of which are still in the kit mountain 20 years later. I bought some of that left handed sandpaper by mistake but luckily my mates left handed so I sold it to him👍 Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted November 4, 2023 Share Posted November 4, 2023 13 hours ago, Piers Bowlan said: Doesn’t the collett go on the motor shaft? Used when you need to reverse the position of the motor shaft and have the prop at the opposite end, if you see what I mean. Had to use that option on a particularly narrow fuselage. Quote Link to comment Share on other sites More sharing options...
toto Posted November 4, 2023 Author Share Posted November 4, 2023 Took a night off tonight. Absolutely shattered. Must be the fresh air from being outdoors at the flying field today. Hopefully back in the saddle tomorrow. I have an exercise to do on the Domino tomorrow to determine an issue on apparent lack of power within the set up so that will be first. Cheers for now Toto 1 Quote Link to comment Share on other sites More sharing options...
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