Craig Carr Posted May 25, 2017 Share Posted May 25, 2017 Well I started this model 3 year ago and after putting it to one side for a year I finished it off and today was its maiden. Brilliant, no bother at all. I did upgrade the fans to the Dr Mad thrust 3S 10 bladers though (I can probably get 4 to 5 minutes with careful throttle control). The tips by the guys above were spot on. I did the same as Neil and Murray and extended the inlets all the way back to the bulkhead (I didnt fit the splitter inside the intake though). I have got access to tarmac at my club though and I feel that made all the difference (or very very short grass may be ok) and I think Tony now states this on his site. But I think realistically 4S would make all the difference Still as pleased as punch with the model. Lovely flyer. Left CofG as per plan (And used 40% expo ) The model on the tarmac just before take off The inlet modification/plan deviation (take it all the way to the bulkhead) Edited By Craig Carr on 25/05/2017 19:54:42 Quote Link to comment Share on other sites More sharing options...
Erfolg Posted May 25, 2017 Share Posted May 25, 2017 I am very impressed. What is much more important is that you are pleased. It is a testament to perseverance, and a really good looking build, well done.. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted May 25, 2017 Share Posted May 25, 2017 Still not flown mine again since I do not have tarmac available. Started to upgrade two of the fans to 10 blade but only one done. Very difficult to retro fit these and wonder if it is really worthwhile. Have nicked the ESCs for the Lanc anyway. Any ideas on 4s packs which would fit? I currently have Zippy compact 2700 3s. Good looking model Craig and glad that it went well. Quote Link to comment Share on other sites More sharing options...
Neil Hodson Posted May 26, 2017 Share Posted May 26, 2017 I used 10 blade 4S fans from Hobby King, Dr Mad Thrust and two 3000 mah Turnigy Nano Tech LiPo's. AUW is 2500 g and I get 8 minutes flying time. Flies very nicely now that I have got everything dialled in. Takes off from dolly without any bungee. Full up elevator until it unsticks. Needs a high alpha approach to slow things down on landing. Throws are 12mm with 40 % expo and 15 % down elevator mixed in to the throttle. Flies nicely scale like on about half throttle but it will go vertical on full chat. To get the weight down I ditched the u/c and most of the wood pack ply parts, substituted 1/16 sheet for the center section in lieu of the supplied 3/32, covered in white solarfilm, anti flash scheme to save weight of spray paint. Took a while to get everything sorted but now is very nice to fly. Quote Link to comment Share on other sites More sharing options...
brfc7 Posted May 26, 2017 Share Posted May 26, 2017 Looks great Craig, I'm looking forward to seeing it myself. baz Quote Link to comment Share on other sites More sharing options...
Craig Carr Posted May 28, 2017 Share Posted May 28, 2017 Posted by Neil Hodson on 09/09/2016 10:35:42: only downside at the moment is a massive pitch up effect with throttle. I have nearly all the available down trim in to keep things level at one third throttle but of course it needs loads of up when throttled back. I will make a mix to put down elevator into the throttle stick for the time being. I wonder if there is a way of angling the exhaust nozzles down at the back to cure this? Neil. Hello Neil, Just noticed your comment about the pitch effect when using throttle. Mine flys without the need for any elevator trim change throughout the throttle curve. Could it be your adjustment to the CofG that's causing that? Craig Edited By Craig Carr on 28/05/2017 07:53:02 Quote Link to comment Share on other sites More sharing options...
John Neale Posted May 28, 2017 Share Posted May 28, 2017 Hi Neil I think Craig is right regarding the CofG. Mine flies beautifully on a 3S 10blade fan set up taking off from tarmac in around 20 yards. However it is slightly tail heavy and on closing the throttles I get a nose up pitch which is a bit more than is needed for a perfect flare when landing. To counteract this I have mixed in 5% down elevon which only comes in when the throttles are closed. This keeps the nose rise under control making landings much easier because as commented on in previous posts this aeroplane glides for ever. It's great fun to fly though looking very realistic in the air. Enjoy yours. John Quote Link to comment Share on other sites More sharing options...
eflightray Posted May 28, 2017 Share Posted May 28, 2017 Mine is sort of based on the TN plan, but built using mostly Depron. She came out at 82" span and uses pushers. Flying weight is 8lb - 12oz. Had about a dozen flights so far, one of my favorites, (the other is in the background, a Spit again based on a TN plan but in Depron, 72" span, 7lb - 2oz ). Ray. Quote Link to comment Share on other sites More sharing options...
Kevin Pearn Posted January 21, 2018 Share Posted January 21, 2018 I now have the plans for the 49” Model and just ordered the Dr Mad Thrust 4s 10 blade 3300kv EDF’s would I be right in thinking that Turnigy nano-tech 3.3 25-50c w/XT-60 would be a suitable battery. I will be fitting the undercarriage. Your thoughts on this would be welcome. Quote Link to comment Share on other sites More sharing options...
Craig Carr Posted January 21, 2018 Share Posted January 21, 2018 Hello Kevin, I personally used 3s units but Neil above used 4s and mentions usingtwo 3000 mah Turnigy Nano Tech LiPo's so I guess your in the right ball park. I would build the model and when you have your wings built (but unsheeted) work out the best sized battery you can fit in between the ribs but bear in mind not to exceed the planned AUW of the model (note there’s a correction on the AUW by Tony somewhere on this thread). A top tip when fitting the webbing on the front spars is to not fit the one between the ribs where the battery is. Then try and get a pack that while slide between the spars and towards the false leading edge. This should help you achieve the correct CofG without any nose weight. Here’s my 3s battery’s in place, they ended up pushed up right against the inner leading edge to get a balance I balanced to the little black dot on the third pic (same as stated on plan) Craig Edited By Craig Carr on 21/01/2018 23:16:05 Edited By Craig Carr on 21/01/2018 23:17:58 Edited By Craig Carr on 21/01/2018 23:19:05 Quote Link to comment Share on other sites More sharing options...
Kevin Pearn Posted January 21, 2018 Share Posted January 21, 2018 Hello Craig, Thank you for your response gratefully received. I have now spent the day reading all the thread and it has certainly given me things to bear in mind. One was why the wings were sheeted prior to fitting to the fuselage when there has to be cuts made then filled. I’ve taken onboard the need to lengthen the intakes and does a splitter increase the performance. I was concerned that I would be building a model that was only good for taxing up and down my drive😂😂 I will be using tissue on the surface as I have never used film before and this is my first venture into Ducted fans. Kevin Quote Link to comment Share on other sites More sharing options...
Allan Bennett Posted February 12, 2020 Share Posted February 12, 2020 The idea of a 48" Vulcan with 4 EDFs attracts me but, having read all through this thread, I'm not sure if this particular one is for me. There seem to be too many posts about it being under-powered and unable to ROG from grass. Since it's quite an old thread, my question is whether more-modern equipment, such as the EDF units offered by 4-Max, have tipped the balance in its favour? Any recent experience anyone? Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted February 12, 2020 Share Posted February 12, 2020 I could only get mine to take off from tarmac so decided to try changing the impellers to 11 blades but did not get too far. Speaking to Tony last year he reckoned that I should convert it to FMS or PowerFun types if possible since these have at least twice the thrust of the old HK units. The snag with these is that you need to upgrade the ESC`s to 40A and because space is limited you would have to find some physically small ones. Tony`s Concorde got away from the Buckminster grass easily enough with the more modern fans. Quote Link to comment Share on other sites More sharing options...
Craig Carr Posted February 12, 2020 Share Posted February 12, 2020 Hello Allan. I would agree with Martin. I made mine with dr mad thrust 11 blade units (on 3s) but you can’t get them anymore it takes off from tarmac which my club has so I’ve never tried grass. I would agree that the newer fms types will probably be the answer as the model is probably comparable in spec (size/weight wise)to the Vulcan which has been evidenced by people to take off from grass I did manage to shoe horn in 4 x turnigy 40amp escs but it does take some planning as Martin says If it helps the model is a peach of a flyer and with the fms units should be fine Craig Quote Link to comment Share on other sites More sharing options...
Craig Carr Posted February 12, 2020 Share Posted February 12, 2020 My Vulcans innards. A bit of a telephone exchange. The escs are along the middle of the fuz and one side. I braced them away (so not touching) the tubes as they were made from A3 laminating pouches and I was worried any heat from the escs may deform them Edited By Craig Carr on 12/02/2020 15:23:44 Edited By Craig Carr on 12/02/2020 15:25:32 Quote Link to comment Share on other sites More sharing options...
Allan Bennett Posted February 13, 2020 Share Posted February 13, 2020 Thanks guys. Looks like I've got myself a project for next winter. Static thrust quoted for the FMS units is 2.39lbs on 4S which, with four of them, should in theory give unlimited vertical If true, I might consider omitting the retracts, and hand-launching. On second thoughts maybe not -- ROG is much nicer. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted February 13, 2020 Share Posted February 13, 2020 You will not require 4s. Beside the flight time being less you will have trouble squeezing the packs into the already very limited space. Quote Link to comment Share on other sites More sharing options...
Murray Hackney 1 Posted February 13, 2020 Share Posted February 13, 2020 Can I refer you way back to my post of 12.06.15. We have an extremely bumpy grass strip, and my Vulcan still flies well to this day off my lightweight trolley. Maybe I was lucky, but I have not changed anything since my original modified specification. Hope this helps! Quote Link to comment Share on other sites More sharing options...
Daithi O Buitigh Posted February 13, 2020 Share Posted February 13, 2020 Posted by Martin McIntosh on 13/02/2020 09:34:54: You will not require 4s. Beside the flight time being less you will have trouble squeezing the packs into the already very limited space. Don't forget, Martin that there are TWO FMS units - the 3S and the 4S. The 4S version running on 3S has LESS thrust than the 3S version running on the same set-up. From the thrust quoted by Allan, he has the 4S versions Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted February 13, 2020 Share Posted February 13, 2020 Agreed, but the 3s FMS and even the PowerFun units have at least twice the thrust of the old Dr Madthrust ones. Don`t go on the bench test thrust, you will be lucky to get half of that when installed in a model. Quote Link to comment Share on other sites More sharing options...
Allan Bennett Posted February 14, 2020 Share Posted February 14, 2020 I don't have any parts yet -- just at the pre-planning stage. I was quoting the data for the 4S version on 4-Max web site. I'll check out the different versions of the EDFs before I order anything. Which, if any, of my present 3S and 4S batteries will fit when I see the plan might be the ultimate decider, unless there's a really clear advantage in one or other setup. Murray, yes I saw your post about a dolly. I tried one once (can't remember what with) and didn't like it. I'd much rather go with retracts if I can. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted February 14, 2020 Share Posted February 14, 2020 2700 3s Zippy compacts just fit as a guide. Quote Link to comment Share on other sites More sharing options...
Allan Bennett Posted April 10, 2020 Share Posted April 10, 2020 My build is underway, but I've made a mistake, I think, with the fan tubes: I just picked up some A3 laminating pouches, but they're much too flimsy. The packet's advertising blurb says that mine are 80 microns, and I can get them in thicknesses up to 250 microns. Any suggestions what's the best compromise between weight and rigidity please, before I waste any more money? Quote Link to comment Share on other sites More sharing options...
John Neale Posted April 11, 2020 Share Posted April 11, 2020 I think the recommended thickness originally was 160 micron acetate but having sampled some I settled for 240 micron thickness. The increase in weight is negligible and it has been perfectly satisfactory on my Vulcan, now nearly 5 years old. I have also used the same 240 micron on my new Hunter and JP. Good luck with the rest of the build Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted April 11, 2020 Share Posted April 11, 2020 Tony, I sent you a PM on this forum asking about moulds for vac forming, only I don't think you have read it yet. I don't want to subvert this thread so I wondered if you could see my PM and comment. Many thanks Andy. Quote Link to comment Share on other sites More sharing options...
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