Ray Wood Posted December 23, 2008 Share Posted December 23, 2008 Hi AllThe overweight model senario would appear to be initially down to wood selection using light ply allows less structure internally , Its also easy to overdo the primer under the colour , Tony normally advises Prymol primer on plastic film to make the paint adhere , the application by cloth or tissue rather than blasting it on seems to be advised on the web , then straight on with the colours .Being a big Brian Taylor designs fan he uses tissue , dope thinned/sanding sealer which manages to keep the weight right down , this would be great on the sheeted surfaces of the Hurricane , but I intend using Solartex on the stringered part of the fuse as its structural . Ray Quote Link to comment Share on other sites More sharing options...
Charles Forsyth Posted December 30, 2008 Share Posted December 30, 2008 Hi All,My Hurricane had it's maiden flight today. I found an experienced model flyer at the club who took the controls for me. My swivelling home made tail wheel made his take-off a little exciting, it was Ok when the rudder became effective.After two minuites of flying the model had an electrical fire which took the pilot by surprise, sudden loss of power so soon. Unfortunately the speed fell away quickly and a turn toward the airfield was enough to iniitate a full spin. The model hit very hard. The model is repairable, amazingly the battery and motor are OK. The cowling withstood the force of vertical impact. The firewall pulled away, the fuselage is mostly intact and the wing has repairable damage.The plane flew very well it could have had a little more aileron deflection above the reccommended rates. I managed to get some video, but did not capture the spin.Yours ayeCharles. Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted December 30, 2008 Share Posted December 30, 2008 Oh dear what a shame Charles - what caused the fire ? Quote Link to comment Share on other sites More sharing options...
Peter 'Ivanna Crashalot' Savage Posted December 31, 2008 Share Posted December 31, 2008 did the experienced flier check the model over before he flew it?my grandad has a caravan at his flying site with almost every model magazine ever in, ill look to see if they have the specials Quote Link to comment Share on other sites More sharing options...
Charles Forsyth Posted December 31, 2008 Share Posted December 31, 2008 The big crunch! Amazingly intact for such a heavy plane. That cowl was unharmed!Part of my fleet, now minus a hurricane!Hi Timbo, The battery wire caught fire, I had extended this wire a little and obviously the extension wire was not up to the job. The model had a reciever battery back-up.Unfortunately the model was too low and far away to glide back to the strip, it spun off the turn as my test pilot tried to turn it toward the airfield. I dont think it needed any trimming, it appeared to fly very well. I am amazed that the fuselage is so intact. The fuselage is an easy repair, not so easy for the wing. I checked the model before it flew, I must admit it was my lack of electrical knowlege and using the wrong gauge of wire to extend the battery lead that caused the failure. I probbably should not have extended it anyway. It,s all a learning curve. The best thing about these forums is we can share our learning mistakes with others to avoid them being duplicated. Charles. Quote Link to comment Share on other sites More sharing options...
Charles Forsyth Posted December 31, 2008 Share Posted December 31, 2008 Here is a link to my maiden flight of my Hurricane....http://uk.youtube.com/watch?v=U_I_uYCT7mc Quote Link to comment Share on other sites More sharing options...
Sandy Taylor Posted December 31, 2008 Share Posted December 31, 2008 Hi Charles, your video has spurred me on to finish the build - i'm up to covering the model at the moment. I'm using oratex which has a slightly fabric texture which accepts paint better. I also made a steerable tail wheel that is linked by pushrod inside the fuselage to the rudder servo - will be interesting to see how that works! How did you end up doing your panel lines? I'm in the same situation as you in that i don't own an airbrush - in hindsight was it worth getting one, or is paint and a brush just as affective?? Sorry for all the questions, but what kind of charger are you using and is it up to the 5s 5000mAh battery?? I'll post some photos on the site soon. I'll bet the weather is a bit warmer here (Oz) than in the old country??!!Sandy Quote Link to comment Share on other sites More sharing options...
Sandy Taylor Posted December 31, 2008 Share Posted December 31, 2008 Here is my steerable tail wheel set up - bit hard to see, but the wire has a collar which sits on top of the spine. The wire is then bent at 90 degrees, and the end fitted with a ball and socket joint which is then connected to the pushrod and then to the rudder servoInstead of fixing the cowl from the outside which would leave visible screw heads, i fixed it through the firewall.Covering in process using oratex, which is a profilm product that has a slight canvas texture to the outside which apparently accepts paint betterMore covering of the bottom of the fuse before i ran out of the oratex....only to find the local hobby shop didnt have any more so will have to order some in....more waiting....not happy!If anyone has any hints or tips about what kind of paint to use and how to do panel lines/rivets/weathering it would be much appreciated!Cheers Sandy Quote Link to comment Share on other sites More sharing options...
Sandy Taylor Posted December 31, 2008 Share Posted December 31, 2008 Some of the detail i have completed including the exhaust, radiator and dust filter which suits on the bottom surface of the cowl. I got all this detail from photos of the hurricane my grandfather flew in ww2 in burma. The hurricanes came from africa so they were fitted with these dust filters which i thought i would replicate.Here are some of the photos of my Grandfathers Hurri when he was flying in Burma (he is my technical advisor on the build!!)On this photo you can see the dust filter fitted under the cowl. I am going to try and replicate the 4 x 20mm cannons on the wing as well. Unfortunately the photos are only in B & W so i cant tell what kind of paint job it had. Anyone who has any links to RAF 11 squadron in Burma please let me know. I really have to do my model justice because Papa won a DFC in this plane, so hopefully i WILL learn from you Charles and not have any electrical fires! Quote Link to comment Share on other sites More sharing options...
Charles Forsyth Posted January 1, 2009 Share Posted January 1, 2009 Hi Sandy,I keyed the profilm covering with wet and dry paper and sprayed the final coat right onto it. I did not use a primer. I worked out where the panel lines were going to be and marked them out with a pencil. You can either press your lines into the balsa wing or scratch them out using a scapel. I opted for the scapel. Next time I think I will press my lines into the balsa with a pencil, spray over the top and scratch out highlights with the blade. I made a template for the panel lines using tracing paper and simply pressed down through it so that I would have an exact mirror image on the opposite wing.I used Revell enamel paints, I found these to be better than Humbrol. The airbrush is a luxury item, it is a must if you want to blend your paint areas or to spray on the soot effect from the exhaust.I am using a BC6 Bantam Dual Power battery charge/discharger, this toy really "rocks" and I would highly reccommend it for charging various types of batteries. It has so many safety features and is a joy to use. There are verious boards available for different batteries, the boards have the connectors for balancing.I am now thinking about buying a VQ Hurricane and converting it to electric, it's almost the same size as the Nijhuis Hurricane. Just make sure those wires are beefy enough to do the job from the battery.I really like your exhausts and the door on the back of the radiator is easy to do and adds extra interest and detail.Have a happy new year, just got back from Dancing the new year in with a live band, Delapina Swing. Last week we had the fabulous JIve Aces! . The dance Lindy Hop is such a riot! (Jitterbug is a simpler form of Lindy Hop).Charles. Quote Link to comment Share on other sites More sharing options...
Charles Forsyth Posted January 1, 2009 Share Posted January 1, 2009 I am amazed that this is what is left after a heavy model hits the ground hard from a vertical spin from about 90 feet. There is a lot to work with here, I thought it would be a big pile of match wood. The cowling has no marks on it and it buried into the ground, just needs recovering. This is an opportunity to remove those heavy dowls which control the rudder and elevator.Wing repairs underway.Do not try this a home..............Battery extension lead. Quote Link to comment Share on other sites More sharing options...
Tom Foreman Posted January 1, 2009 Share Posted January 1, 2009 Hi Charles what gauge wire did you use and what sort of current were you pulling?CheersTom Quote Link to comment Share on other sites More sharing options...
Charles Forsyth Posted January 1, 2009 Share Posted January 1, 2009 Hi Tom,I am not sure what gauge wire I used, it's some that I bought last year and was using with my 11 volt lipos.I dont think it's a good idea to have such a long extension wire either, unfortunately I am no expert. The current would have been very high, I think Derek flew the model at full bore, the 4Max 5sLipo charges to over 20 volts and I had a 70amp Opto ESC. I know it would have certainly been in excess of 1200 Watts. I was never brave enough to put the watt meter on to measure the current. I trusted the 4Max reccommended set-up. It was my lousy wire that created the problem. There was so much power from my electrical set-up, it never would have needed constant full throttle. I am going to call 4Max to buy some heavy duty wire similar to what is on the battery.Charles Quote Link to comment Share on other sites More sharing options...
Peter 'Ivanna Crashalot' Savage Posted January 1, 2009 Share Posted January 1, 2009 unlucky never give up though! Quote Link to comment Share on other sites More sharing options...
Tom Foreman Posted January 2, 2009 Share Posted January 2, 2009 Thanks Charles, I have used 12 AWG for battery harnesses up to 900W (60A) and 14 AWG for motor wires (three wires to spread out the load) at the same power. Just interested at what current your wire failed, if it was 14 AWG at 1200W (18.5V x 65A) perhaps at a guess. I know that when you get to really big EDF power systems e.g. 3.5KW you have to buy big bullet connectors because the Dean plugs just melt away . All good information for when I get around to building one .Cheers,Tom Quote Link to comment Share on other sites More sharing options...
Tom Foreman Posted January 2, 2009 Share Posted January 2, 2009 Just did a quick search on the Web for current rating of wire, and their conservative figures read like this14 AWG Max Continuous Load 30A 12 AWG Max Continuous Load 41A10 AWG Max Continuous Load 55A8 AWG Max Continuous Load 73A6 AWG Max Continuous Load 101A These values are for longer runs on car electrical installations and they do say for battery packs with short runs that higher currents can be used as cable flexibilty and weight will be more important. The wire insulation also has an effect as well.I personally would use 12 AWG for your battery cable, but you might want to bench run it first to see if the wire melts before you commit it to the air, at least put your multimeter on it and check the current is within parameters. I once used a recommended prop size for a recommended power system by the manufacture given in the instructions and it pulled 80A instead of its rated 60A max, on closer inspection of the instructions they were referring to a cooler wind version of the motor that I had been supplied with and a simple change of prop dropped the current, glad I found out before the maiden Tom Quote Link to comment Share on other sites More sharing options...
Charles Forsyth Posted January 2, 2009 Share Posted January 2, 2009 Hi All,George at 4-Max gave me a link to this interesting website for Silicone wire and connectors.Lokk at the Ashlock connectors I have never seen these before. http://ashtekelectronics.com/shop/index.php?target=pages&page_id=what_is_ashlokhttp://ashtekelectronics.com/shop/index.phpThe advise is to make sure it's silicone wire as this can withstand higher tempretures, no more than 12 inches in length if using an extension lead. Use the wire on your battery as a guide, 4mm wire that can take upto 100amp would be OK.http://ashtekelectronics.com/shop/silicone-cable-p29836.html ****SILICONE WIRE 4mm*****Charles. Quote Link to comment Share on other sites More sharing options...
Ray Wood Posted January 5, 2009 Share Posted January 5, 2009 Hi CharlesGreat shame about the Prang ! Looks like your getting on well with the repairs .The down side of electric versus - ic is you can hear when an engine cuts .Did you build any washout into the wings ?RegardsRay Quote Link to comment Share on other sites More sharing options...
Tom Foreman Posted January 5, 2009 Share Posted January 5, 2009 The problem isn't 'incendiary' its the short life span of the batteries that I have problems with, costs a fortune replacing worn out batteries! Hope they bring out a battery with a bit of a longer life. Quote Link to comment Share on other sites More sharing options...
Peter 'Ivanna Crashalot' Savage Posted January 5, 2009 Share Posted January 5, 2009 are you referring to lipos? i have some lipos that are about 3 yrs old and they still work Quote Link to comment Share on other sites More sharing options...
Tom Foreman Posted January 5, 2009 Share Posted January 5, 2009 Lipos and now my beloved A123's, I must be doing somthing wrong as I'm lucky to get 6 months out of them. I mean they still work but they are 20% down on capacity. Think I might start using the 'store' facility on my charger Quote Link to comment Share on other sites More sharing options...
Peter 'Ivanna Crashalot' Savage Posted January 5, 2009 Share Posted January 5, 2009 i use really cheap lipos, all our expensive ones have puffed up, the cheap ones though have not Quote Link to comment Share on other sites More sharing options...
Tom Foreman Posted January 5, 2009 Share Posted January 5, 2009 I've never puffed one, perhaps I expect too much from our poor lithium friends Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted January 5, 2009 Share Posted January 5, 2009 Tom Foreman wrote (see)Lipos and now my beloved A123's, I must be doing somthing wrong as I'm lucky to get 6 months out of them. I mean they still work but they are 20% down on capacity. Think I might start using the 'store' facility on my charger Thats a good start Tom. Quote Link to comment Share on other sites More sharing options...
Peter 'Ivanna Crashalot' Savage Posted January 5, 2009 Share Posted January 5, 2009 actually, i seem t remember the date we wrote on them being 2002 Quote Link to comment Share on other sites More sharing options...
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