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RE: JMA TOPGUN 2013 MAY 18/19
Hi Pat, Its just the cheap HD cam from Hobby King costing about £26, it uses a micro SD card, has its own lipo, its small and light at about 2/3 the size of a matchbox and can record for hours. Its simply packed off to give the right angel with servo tape and then stuck on plus a strip of good old gaffer tape for extra security. Its was all a bit last minuet, but I was reminded I had the cam in my Tx case wile waiting for Jamie to clear the runway so quickly popped it on.If you look carefully there's another cam on the canopy from the guy that was doing the filming of the event with his Hex-copter, it will be interesting to compare.I've always got the cam with me if you want to borrow it and you can give it a go when were at the field, CU soon?Regards Mark
Posted on: 5/23/2013 4:55 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11520006
RE: JMA TOPGUN 2013 MAY 18/19
Hi Mark S, no problem, ill hang on to it for now and leave it in the van, should our paths cross soon you can have it back then possibly at the next CJM?Regards Mark V
Posted on: 5/22/2013 10:40 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11519370
RE: JMA TOPGUN 2013 MAY 18/19
Hi There was also a dark blue fold up chair left behind Sunday evening, if its yours contact me and we can arrange to get it back to you. I managed to get a couple of flights in later on the Sunday when it was quite with my JL 1/6 F16 with a cam attached to the top of the fin, gives you a good look at the airfield from on high. https://www.youtube.com/watch?v=NXhO6xyudeg
Posted on: 5/22/2013 6:29 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11519097
RE: JET LEGEND VIPER BUILD THREAD
Congratulations Jeremy on your first flights As you have found out shes very stable at full flap, You can force your way in without picking up speed and get a very nice flare with no tendency to balloon. I remember mine too did roll a little but only with half flap on the first flights and had to be trimmed with a small bit of mixing Have many more and enjoy you up coming Jet Meet Regards Mark
Posted on: 9/1/2012 1:23 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11213301
RE: JET LEGEND VIPER BUILD THREAD
Hi Guys Here's my latest CG update, I'm now back to 49mm behind the wing tube centre with empty tanks and gear down. There is no tendency to balloon on the approach and it is still lands like its on rails. Its very stable in normal flight and at speed, strangely I still have quite a lot of up trim ? How ever at very "very" slow speeds clean ive got it for the first time to drop a wing in both straight flight and in a very "very" turn. The good thing is as soon as I let it pick up evan a littel speed it recoverd straight away. I have also tried spins upright and inverted and it recovers easaly just by letting go. Im not sure this is a result of the more rearward CG or I am just trying harder with the Viper as im gettin use to it? When I get a chance ill try it all again with the more forward CG and report back. I was teasing the hell out of it and would never imagine anyone silly enough to try flying it this slow or tight wile low or on the landing approach. In normal flight all manoeuvres are smooth loops are true fast and large or slow and tight, slow rolls still need a fair bit of forward stick wile inverted. I'm not going to go any further and will now settle on 35-40mm as I have noticed no diffrence beond this piont and still feels very safe at this position, Have fun The pic below shows the elevator trim setting for norm flight, it just like every Flash ive seen and owend!
Posted on: 8/26/2012 8:48 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11189506
RE: JET LEGEND VIPER BUILD THREAD
Yes, Dispite going to some lengths with the first install to keep it all forward to obtain the recommended and very safe CG, All of the 112mm dia turbines seem to weigh about the same at between 1400-1600g including the T12. Had I known that the CG was safe further back I would have just done my more usual install and layout as it has ended up now. It still did not take me long to put it together, it arrived on the Monday and was ready to fly on the Thursday despite having to try and fit everything up front. Had I gone with my instincts and made my usual layout as it is now I could have saved another day on the bench, its a very quick build. There plenty of scope to move things around for lighter turbines, having the ECU battery on top of the tank at the very least would be a given. I may well relocate my Rx battery just behind the nose wheel cover and refit my lights lipo further back along side the ECU Lipo You could fit the ECU Lipo along side the Turbine on its mounting rail, that should help a lot.
Posted on: 8/26/2012 8:18 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11178249
RE: JET LEGEND VIPER BUILD THREAD
Nice one Ian, You now know They are beautiful to land. Nice bit of turf you have to play on there. All we need now is a very large wind brakes all the way round our flying sites and we can all go out to play. Will it ever stop blowing. Regards Mark V
Posted on: 8/26/2012 8:13 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11178572
RE: JET LEGEND VIPER BUILD THREAD
The only other mod ive made to my Viper is to place wedges between the carbon plates and the UC to splay the legs outward a bit. I thought they looked a bit odd when straight, allmost as if they were splaying inward as std when it sat on the ground. I also poped a wedge behind the nose wheel retract unit to lean it forward a bit. When retracted the joint on the nose wheels trailing link is now only just inside the wheel well. Its only 2-3deg and prob only makes a small differance but i got board one evernig so tinkerd They handel well on the ground anyway I think it just looks a littel better?
Posted on: 8/26/2012 8:11 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11206310
RE: JET LEGEND VIPER BUILD THREAD
Hi all I was asked a question today via email regarding the flap mod i made to my Viper and thought it might be usefully to others Question I''m maidening my Viper Jet next Sat and was wondering if you could tell me what amount of down trim you have for your take off and landing flap. Also I did the mod to flap horn like you did, do you find it has a bit of play upwards when set level to the wing? Reply Measured at the inboard of the elevator I have 3mm of down elevator for take off and a further 1mm for landing. I have 6mm up aileron or "crow" with landing flap, this helps negate large amounts of elevator trim. I dont have any "crow for take off flap.The flaps are set to 32mm for take off and 50mm for landing. Its also got a 4 sec slow down set on the flap to smooth every thing out. Backlash on flap I do get a bit of up play when the flaps are neutral and was a bit worried at first but its been clocked on my GPS at over 230 mph and has not fluttered yet. I think perhaps I put the flap horn a little too rearward and its a little short but it dose give good leverage every were but at neutral. I gave it some thought today and think I have cured the upward backlash completely by glueing a wedge under the linkage, see the pics it works a treat! Regards Mark
Posted on: 8/26/2012 8:06 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11206304
RE: JET LEGEND VIPER BUILD THREAD
Nice to see another JL Viper airborne, well done sham your day was cut short. I hope you enjoy flying yours as much as I have flying mine. Looks fantastic on the Ground, How is the vis in the air with it in the Black and Bronze? Regards Mark V
Posted on: 8/6/2012 4:14 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11182593
RE: JET LEGEND VIPER BUILD THREAD
This is were I moved the tiny Xicoy V10 ECU and its battery too, The tray also doubels as a tank brace. Theres plenty of room up there for any size ECU and if extenden over the inlet duct the wieght could go evan further back. Be shure not to use too long a screw to hold the tray down to the cross braces or you will have extra vents in the tanks! You can see the new home for the pump in the "V" of the duct, this all moved the CG back about 25mm.
Posted on: 8/3/2012 3:48 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11178152
RE: JET LEGEND VIPER BUILD THREAD
This might help, I originally made an under tray to hold the retract and brake valves along with the pump and turbines valves in an effort to get everything forward. I like to place the pneumatics under the main tray out the way if i can as its hard to remove the main tray with lots of pipes etc attached at a later date. The last pic is after I removed the Jetronic E-Valves and replaced them with a simpel Beotec C36 Brake-Retact valve and moved the pump and turbines valves back to shift the CG. You may note in the second pic I found room for a second air tank, Ive found it to be unnessersery as the retracts are very reliabel and get lots of cycels but it could be used for separate brake air?
Posted on: 8/3/2012 3:45 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11178150
RE: JET LEGEND VIPER BUILD THREAD
Here is a pic of the T12 turbine first before I moved the valves back and then after to help with the new more rearward CG The CG at the moment is more or less at the rear of the inlet duct as you see it in the pic.
Posted on: 8/3/2012 3:43 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11178145
RE: JET LEGEND VIPER BUILD THREAD
Hi Steve The Spark trailing link UC is very well made and has plenty of travel, its also air sprung so no springs to get weak or stretch. Ive not been able to fly from our grass patch yet as we have ripe crops around but flying from grass is one of the main reasons I've bought the Viper The VT80 will be ideal, your not going to get the silly vertical I'm getting with the 27+lb from the T12 but it cant hurt the handling if its a pound lighter. I'm very sure it would fly very nicely with anything from an old P80, Wren Super Sport, K80 and be brilliant on the new Wren 100 or P100. I did have 5-6oz of lead in the nose to start with but soon lost that along with its 2200 singel cel Lipo for the lights I am now useing a lighter Rx and ECU battery's and then moving stuff back to above and behind the tanks. Theirs plenty of scope to shift gear, For a start I can move the Rx pack up to 400mm further back and could place the ECU pack on top of the duct or evan along side the turbine. The T12 turbine its self centres 100mm behind the CG so its weight hasn't a huge effect on the overall CG and you still have the pump fro your VT80 you could fit rearward. For those with heaver turbines, if needs be you could place weight as far forward as 800mm from the CG but should not need to. With lighter turbines you could put items as far back as the rear of the huge turbine bay.
Posted on: 8/3/2012 3:42 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11178138
RE: JET LEGEND VIPER BUILD THREAD
Here is a pic of how I Have set up my flap linkages on the JL Viper. I like to use std 3mm Kwik links as this allows me to keep the servo arms short and can use all 100% travel . The links can also "disappear" into the slot with out having to make the slots very much wider so look nice and neat. I first cut off the horn on the flap hinge and fixed a new epoxy glass one in line with the slot in the servo hatch. The Flaps are hollow so used plenty of epoxy and micro balloons filling the area around the new slot. The horns also placed further back to give better leverage at full down flap with out the pivot point riding over centre. Seams to work well and I have managed to keep 100/95% servo travel and in flap settings use 88% for up, 0% for take off then 80% for landing. If I had kept to the ball links I would have had to use much longer arms and reduced the servo travel halving there effective power. Ether that or use short servo arms then cut large slots in the very nice hatches which seamed a shame as they look really neat Threes nothing wrong with ball links and the JL ones supplied are very good but i did not feel they were called for here. The same is true for the Ailerons and Rudder and I have used Kwik links there to. I'm am sure the reason why flutter has occured on some other fast airframes is were the servos are at a disadvantage. We pay a fortune for good powerful servos, I try to get all 11kg usefull tork out of my JR 8421 servos were I can by useing at the very least 100% travel. If you have to set them as low as 50% of servo travel "for full control movement" you will only get 1/2 the efective holding power from them.
Posted on: 8/3/2012 3:16 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11174716
RE: JET LEGEND VIPER BUILD THREAD
Hi Guys Ive now had 23 flights with my Viper TL12 combo over the last few weekends and thought I would confirm the settings Ive given Jeff at Zedjet regarding the CG im useing for the Viper I am now at 36mm back from the centre of wing tube, Still got some up trim in and ive I have flown her in twice now with completely empty tanks and shes still rock steady. Im useing a DX18 so if anyone wants to try my knife edge and flap comp setting ill post if you wish, there all but spot on now but may change as I go evan further back with the CG!
Posted on: 8/3/2012 3:04 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11174574
RE: JET LEGEND VIPER BUILD THREAD
I'm quite please with this little trick with the power box Duel switch leads. Ive glued them together then made a lite ply flange, cut a hole in the top deck pused it through and fixed it with two small screws from the top. Nice and simple and keeps the leads from flying around in the cockpit or disappearing through a hole and hiding under the tray. I also made a housing from lite ply for the switch, its essayer to get to the buttons and the switch doesn't get in the way of anything under the tray. I still cut a hole in the deck under the switch as its very important to keep the switch cool, you may have noticed they get quite hot in use.
Posted on: 8/2/2012 3:26 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11178165
RE: JET LEGEND VIPER BUILD THREAD
Here you go Jeremy, it just in front of the right tank, note I've lined the tray with 2mm lite ply to tidy things up, the pre cut holes never seem to be just were you want them! I also made a "mud guard" or housing for the nose wheel for when it finally gets to the grass strip, its a nuisance picking grass out of the pilots teeth every time you land! Ive also shown how I've retained the Rx Lipos, easy to take out to recharge. I have also cut a RX sized hole for the servo leads to come through the tray, that means I don't have to unplug every thing to remove the tray
Posted on: 8/2/2012 3:05 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11178156
RE: JET LEGEND VIPER BUILD THREAD
Hi Jeremy Its still very stable at 36mm back so 20-25 will be fine but be ready to trim the elevater back a bit to keep the nose up. Ive have made it so I can move stuff around now so I will be creeping the CG further back this week end. Dont expect and thing dramatic to happen but wish me luck
Posted on: 8/2/2012 1:45 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11178128
RE: JET LEGEND VIPER BUILD THREAD
Just been given some vids of my first day out with the Viper, bit shakey and a lot of wind noise but should give some idear of how she handels http://www.youtube.com/watch?v=XML-iCg-_y0&feature=plcp http://www.youtube.com/watch?v=wrLl7unmR68&feature=plcp http://www.youtube.com/watch?v=wKZZ9LdbfNs&feature=plcp Im no expert pilot but the Vipers steady evan in on a windy day and is very easy to land dispite the bumps.
Posted on: 8/1/2012 9:00 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11177230
RE: JET LEGEND VIPER BUILD THREAD
Just taken the basic settings from my Viper and DX18 Tx Elevator is 16mm each way with 30% expo at full rate, fairly soft but enough for hard turns if you feel the need to pull the stick hard. I am still flying with 3mm up trim with the CG 36mm back in norm flight at half power and if you aply full power it only then will start to clime. Needs nearly 1/4 forward stick inverted to keep level. Ailerons are 20mm each way with 30% expo at full rate , quite lively at full rate so I've been using 80% rate for norm flight Rud 23mm each way and she will clime out of knife edge so 1/2 to 2/3 is enough for a pass Rud to down Elevator for knife edge is 13%, might try a bit more but moving the CG might change that Rud to opposite Aileron is 18% Flap is 24mm for take off with 18% down Elevator but still needs a bit more but thums are taking care of this small trim change at the moment. Landing is set to 55mm with 5mm crow which slows it down really well, Ive got 22% down trim which seams about right Ive also got a 4 sec delay to smooth it all out Clean it takes an age to slow down and you run out of space waiting for it to slow enougth to try stalling it as its a very clean airframe, but the stall is straight and "mushy" it wont drop a wing With the flap half down it realy hangs in there wont stall at all just nods, I did not push it any harder as it was so slow at that point it might have got a bit hairy. Landings are a joy and if you wish she will come in at well over 45 deg with out speeding up, flares nicely and will not balloon at all. Once you get the wheels down on the deck she sticks to like a limpet but oil up the brakes as the wheels are set wide and it can swing if you don't have a graduated brake valve. With the Jetlegend T12 on board and 24mm of flap she will lift off in about 60-80 feet on tarmac and then go vertical if you feel the need, evan with all 3lt of fuel on board! The Jetlegend/Spark T12 Turbine has got to be one of the best value 27lb turbines around, I've got well over 4 hours on it now and nearly 50 flightsand its never missed a beat Its internal kero start that works first time every time. I get 9,1/2mins on 3lt with enough for a further 1,1/2 mins for go rounds (ive ran the tanks dry wile flying just to find out!) The Viper is 22lbs dry so add another 6-7+ lbs for the fuel and at that weight I can clime vert from the ground as high as I can see all for only £1500, ask Jeff at Zedjet if you want one.
Posted on: 7/30/2012 1:01 PM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11174661
RE: JET LEGEND VIPER BUILD THREAD
I have not tried it yet but im sure we can share model memories just by mailing the file on the memory cards in the DX18 Txs Im willing to give it a go if any one is intrested. I realise the throws and sub trims would need to be alterd but it might be helpfull?
Posted on: 7/30/2012 12:38 PM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11174599
RE: JET LEGEND VIPER BUILD THREAD
Hi Again Sorry if I'm playing catch up on this thread but i noted you guys have had i prob with hooking up the 2mm air lines. Well i had the same issue but sorted it quite quickly buy simply pushing the line on to std fittings, every things stayed airtight so far.
Posted on: 7/30/2012 10:23 AM by Author "modelmancan"
in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=11174596
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