Professional Viper 2M Build
#1
Thread Starter

My Feedback: (30)
Well with the permission from John at Aeroplane Factory Jets in Canton,GA. I decided to post this build thread for the Skymaster Viper 2M. As work and a new baby boy has taken up most of my time John was recommended to me by another RCU member. I think this type service is exactly what an individual like myself needs, and he's very reasonable to boot. John has been a wealth of knowledge for me and takes the time to take all my calls and answer everyone of my questions that I might have. On top of that he is one of the nicest guys I have talked to in the industry..
John plans on going through the plane, replacing factory air lines, reinforcing where need be, beefing up LG etc...Here are some photo's and John's info. I will be updating this as John updates me...
John Monaghan
Aeroplane Factory Jets
8587 Comming HWY
Canton,GA 30115
334-7281499
John plans on going through the plane, replacing factory air lines, reinforcing where need be, beefing up LG etc...Here are some photo's and John's info. I will be updating this as John updates me...
John Monaghan
Aeroplane Factory Jets
8587 Comming HWY
Canton,GA 30115
334-7281499
#4
Thread Starter

My Feedback: (30)
List of Equipment going in...
Jet Cat P-80SE
Powerbox 40/24
EV5U-PRO
JR DS8411's on Steering, Rudder, and Ailerons
JR DS8711's on Elevator, and Flaps
JR921 Receiver
SWB Arms with stainless ball links
Also going with a JMP Accumulator
Jet Cat P-80SE
Powerbox 40/24
EV5U-PRO
JR DS8411's on Steering, Rudder, and Ailerons
JR DS8711's on Elevator, and Flaps
JR921 Receiver
SWB Arms with stainless ball links
Also going with a JMP Accumulator
#6

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From: Coventry, Warwickshire, UNITED KINGDOM
The 8711's are way over the top for the baby viper, My big viper has 8411's on all surfaces except the rudder and Ali's baby viper has even smaller servo's on the elevators on his baby viper.
Ali recently had an incident where he had to land early in the flight, still carrying a lot of fuel and the difference in the extra weight was really noticeable. I think with your larger servos, powerbox and big airpower valve, that you are going to end up with a model weighing considerably more than Ali's and it will be detrimental to the way it flies. The same goes for the SWB arms and stainless ball links. It’s all extra weight that isn't really necessary. One of the reasons the 2m flies so well and in some respects better than the big viper is that it's has a lower wing loading. It would be a shame to loose that by building a heavier model than you need to.
Duncan
Ali recently had an incident where he had to land early in the flight, still carrying a lot of fuel and the difference in the extra weight was really noticeable. I think with your larger servos, powerbox and big airpower valve, that you are going to end up with a model weighing considerably more than Ali's and it will be detrimental to the way it flies. The same goes for the SWB arms and stainless ball links. It’s all extra weight that isn't really necessary. One of the reasons the 2m flies so well and in some respects better than the big viper is that it's has a lower wing loading. It would be a shame to loose that by building a heavier model than you need to.
Duncan
#7

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From: Northamptonshire , UNITED KINGDOM
My thoughts exactly.
If you want a jet to pile the bling into then go with the bigger Viper. The 2m is as good as it is when kept light and simple. Just my thoughts, feel free to go your own way.
Regards Al
If you want a jet to pile the bling into then go with the bigger Viper. The 2m is as good as it is when kept light and simple. Just my thoughts, feel free to go your own way.
Regards Al
#9

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From: North Port,
FL
KX450:
I agree completely with Duncan. We (Hatcher's Hangar) built ours "box stock" other than Bill creating a beautiful set of vents between the ventral fins. Servo's were 8411 equivilents by Hitec. You must use the small and thin aileron flat type servos in the stabs. Nothing else fits. We used JR
We did opt for the EV5U (weighs 2oz more than three servos and three valves) 5 way valve for simplicity. Once you use this unit, it is hard to go back. Ditch the PowerBox or any system similar. . .simply not needed plus there is little room under each cockpit floor.
Having installed Cheeta and complete system added 4lb 1 oz to the airframe. Total weight including Blue Box toys pilot and UAT full came in at 26lb. 1oz. for the paint in the mold 2M Viper we received.
We opted to replace all air lines and the needed T and Y air line fittings. Cylinders were tested and found to be good. The included AirPower fill valves were tossed. . .they leaked and were replaced with Robart "one way" fill valves. Less weight as well. You can see our 2M install pictures on the other Viper thread.
Maiden soon.
Good luck with yours.
Eric
I agree completely with Duncan. We (Hatcher's Hangar) built ours "box stock" other than Bill creating a beautiful set of vents between the ventral fins. Servo's were 8411 equivilents by Hitec. You must use the small and thin aileron flat type servos in the stabs. Nothing else fits. We used JR
We did opt for the EV5U (weighs 2oz more than three servos and three valves) 5 way valve for simplicity. Once you use this unit, it is hard to go back. Ditch the PowerBox or any system similar. . .simply not needed plus there is little room under each cockpit floor.
Having installed Cheeta and complete system added 4lb 1 oz to the airframe. Total weight including Blue Box toys pilot and UAT full came in at 26lb. 1oz. for the paint in the mold 2M Viper we received.
We opted to replace all air lines and the needed T and Y air line fittings. Cylinders were tested and found to be good. The included AirPower fill valves were tossed. . .they leaked and were replaced with Robart "one way" fill valves. Less weight as well. You can see our 2M install pictures on the other Viper thread.
Maiden soon.
Good luck with yours.
Eric
#10

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From: Coventry, Warwickshire, UNITED KINGDOM
Here you go, this was taken from Ali's thread about the 2m viper, there is a spec list at the bottom
My current 2m is running with zero nose weight, even with a P-80 Se installed. ( The first needed a fair few ounces of lead to balance) The reason being as follows..
On VJ2m number 1 I installed standard size JR 8411's in the stabs. I just felt safer this way as its my tried ands tested servo set up. On model number 2 I went with the suggested Midi size servo and fitted the JR DS3201. This is a plastic geared 4 KG of power digital midi servo. I know to some this will appear to be too small and under spec a servo, and I have to admit I was dubious. But to date I have had 4 flights with this servo set up and pushed the model as hard as I can with repetitive positive and negative snaps. Continuos rolling loops and cuban eights. Square loops, constant loops ( Both inside and outside) Tightening in diameter till the model eventually snapped out and some very aggressive and high speed pull to push manoeuvres at high speeds. Basically a flight envelope outside of what I would expect top see of a jet of this type, and have had no issues, flutter or even a feel of control surface response fading.
I am happy to recommend a midi servo set up, but fully understand why some may want to use smaller servos. To these end users I would say, it is possible to fit 8411 size servos. it does require some careful work sanding out the servo carrier rib in the stab and the surrounding area, just be aware you may need to add nose weight to counteract the extra weight of the larger servos so far aft in the model.
On the second model the turbine was also moved forward some ways compared top the first. I still have another 2-3 inches that I could go but the restricting factor is the tailpipe length. On this model I have moved the turbine as far forward as I dare ( I have 1.5 inches between tail cone of the P-80 to the inlet to the tailpipe ) and even then I have had to cut down the cosmetic bolt on tail come that bolts on to the outside of the fuselage by approximately 2 inches. This is not noticeable and was only a precautionary measure to stop the thin fibreglass from melting. I have also added a coat of heat shield paint to the inside of the remaining tail cone just to be safe. So far I have seen no distortion of this tail cone, but will be sure to update as time goes on if this changes.
I guess all of the above is just a heads up to say to owners that it is finally possible to get a nice scale jet without having to add nose weight, or huge batteries to balance. You just need to be aware that a bit of attention to the very back end of the model will pay dividends.
The ventral fins on both my models have come loose. I must say not in normal use but rather when I caught them loading them in the van. As when the model sits on its belly they are very low and easily knocked. Both times the same thing happened in that the 3mm threaded rod broke free from inside the ventral fin. What I do know is drill a 4mm hole through the inside skin of the ventral fin ( So it is not visible when they are fitted) I then pour rocked powder in and around the the thread of the rod inside the ventral and cyno to harden. You could use epoxy/ aeropoxy just be mindful of the weight added to the back end.
Some will argue that it is better that these fins are easily detached if knocked so will choose not to do this mod, which is fine as they have never come loose in the air.
Ref the finish of the model..
So far the only VJ2m's that I have seen or had experience of have been painted in the mould examples. The initial impression of these as they come out of the box has not been great. With both myself and customers commenting on the dull finish of the paint work, and appearances of quite a few surface blemishes and imperfections. This is one of the draw backs I guess of a paint in the mould finish. The good news is that it's not all as bad as it first appears. I have found that most of the imperfections seem to be removable, and the dull finish is also workable. Both my models have had a few hours spent by me in T cutting and polishing the top coat, which has in both cases transformed the appearance of the model. I found that I could remove many if not all of the finger prints or marks which seem to be in the release agent. Then a polish with a good car polish really helped bring the top coat to a good shine. I am sure many of those that have seen either of my vipers up close can testify to that?
I also found that a little bit of time spent on markings makes a world of difference. I have worked with a great vinyl guy here in the UK to make a complete sticker sheet that really helps transform the VJ2M. These include the following .
2x Viperjet 2m logos ( just no 2m for those with the larger ones )
2x Als Hobbies ( These will be free and for customer to use as they please )
2x Chrome fuel fill caps
2x Chrome Vents for rear under tail near tailpipe
2x Chrome circles with rivets for rear side of fuselage
2x Chrome without rivets ( same area as above)
8x Chrome vent holes for vents on the very front of the nose
2x Spektrum stickers
2x Jet Cat stickers
the above can be changed by request
200 Chrome rivets
40 smaller chrome rivets that will work for the rivets around the apu exhaust on rear side of fuselage and if you want to they also look good going down the side of the intakes.
As well as lots of lengths of 3mm black trim line that when applied to the line between yellow and white really makes that contrast stand out.
All in all I spend an entire evening on just the appearance of the model. Between the T cut, polish and sticker application. I really do think this is a worthwhile exercise as it transforms the model.
The equipment list of what I have used in the model is as follows.
Jet Cat P-80 Se
JR 8411 x 5. Ail. Flap and rudder JR super servo horns on flaps. After market longer horns on Rudder and ailerons to get throw ( These were one hole longer than JR horns)
JR 3201 x 2 Stab with JR super servo horns to get movement required.
Hitec 645 steering
Spektrum 12100 Power safe Receiver
Airpower EV5u multi valve and sequencer
I changed my door rams to BVM 3" stroke ( Mains only. nose is stock)
3300 Mah Jet Cat Lipo for ECU
2x 2500 AA size Nimh 6volt RX packs. All bats in the nose section either side of nose retract bearers.
Dubro 40 Oz tank as secondary Tank
UAT ( or equivalent)
BBI/ Dragon Pilot in front seat only .
We are currently working on a really professional set of wing bags for the 2M. They will be a smaller set of what we have already for the Big Viper jet and go along way to helping protect your pride and joy. I will update when these are available.
Sorry to waffle on, but these are things I have picked up from my experiences and I hope they may help new or possible VJ2M customers. If you have any questions then please feel free to email me directly on [email protected]
I will try to follow up soon with some photos of various things on my 2M as well as an accurate centre of gravity and what control throws that I am using.
Read more: http://www.rcuniverse.com/forum/m_96...#ixzz0rlcgAOWY
My current 2m is running with zero nose weight, even with a P-80 Se installed. ( The first needed a fair few ounces of lead to balance) The reason being as follows..
On VJ2m number 1 I installed standard size JR 8411's in the stabs. I just felt safer this way as its my tried ands tested servo set up. On model number 2 I went with the suggested Midi size servo and fitted the JR DS3201. This is a plastic geared 4 KG of power digital midi servo. I know to some this will appear to be too small and under spec a servo, and I have to admit I was dubious. But to date I have had 4 flights with this servo set up and pushed the model as hard as I can with repetitive positive and negative snaps. Continuos rolling loops and cuban eights. Square loops, constant loops ( Both inside and outside) Tightening in diameter till the model eventually snapped out and some very aggressive and high speed pull to push manoeuvres at high speeds. Basically a flight envelope outside of what I would expect top see of a jet of this type, and have had no issues, flutter or even a feel of control surface response fading.
I am happy to recommend a midi servo set up, but fully understand why some may want to use smaller servos. To these end users I would say, it is possible to fit 8411 size servos. it does require some careful work sanding out the servo carrier rib in the stab and the surrounding area, just be aware you may need to add nose weight to counteract the extra weight of the larger servos so far aft in the model.
On the second model the turbine was also moved forward some ways compared top the first. I still have another 2-3 inches that I could go but the restricting factor is the tailpipe length. On this model I have moved the turbine as far forward as I dare ( I have 1.5 inches between tail cone of the P-80 to the inlet to the tailpipe ) and even then I have had to cut down the cosmetic bolt on tail come that bolts on to the outside of the fuselage by approximately 2 inches. This is not noticeable and was only a precautionary measure to stop the thin fibreglass from melting. I have also added a coat of heat shield paint to the inside of the remaining tail cone just to be safe. So far I have seen no distortion of this tail cone, but will be sure to update as time goes on if this changes.
I guess all of the above is just a heads up to say to owners that it is finally possible to get a nice scale jet without having to add nose weight, or huge batteries to balance. You just need to be aware that a bit of attention to the very back end of the model will pay dividends.
The ventral fins on both my models have come loose. I must say not in normal use but rather when I caught them loading them in the van. As when the model sits on its belly they are very low and easily knocked. Both times the same thing happened in that the 3mm threaded rod broke free from inside the ventral fin. What I do know is drill a 4mm hole through the inside skin of the ventral fin ( So it is not visible when they are fitted) I then pour rocked powder in and around the the thread of the rod inside the ventral and cyno to harden. You could use epoxy/ aeropoxy just be mindful of the weight added to the back end.
Some will argue that it is better that these fins are easily detached if knocked so will choose not to do this mod, which is fine as they have never come loose in the air.
Ref the finish of the model..
So far the only VJ2m's that I have seen or had experience of have been painted in the mould examples. The initial impression of these as they come out of the box has not been great. With both myself and customers commenting on the dull finish of the paint work, and appearances of quite a few surface blemishes and imperfections. This is one of the draw backs I guess of a paint in the mould finish. The good news is that it's not all as bad as it first appears. I have found that most of the imperfections seem to be removable, and the dull finish is also workable. Both my models have had a few hours spent by me in T cutting and polishing the top coat, which has in both cases transformed the appearance of the model. I found that I could remove many if not all of the finger prints or marks which seem to be in the release agent. Then a polish with a good car polish really helped bring the top coat to a good shine. I am sure many of those that have seen either of my vipers up close can testify to that?
I also found that a little bit of time spent on markings makes a world of difference. I have worked with a great vinyl guy here in the UK to make a complete sticker sheet that really helps transform the VJ2M. These include the following .
2x Viperjet 2m logos ( just no 2m for those with the larger ones )
2x Als Hobbies ( These will be free and for customer to use as they please )
2x Chrome fuel fill caps
2x Chrome Vents for rear under tail near tailpipe
2x Chrome circles with rivets for rear side of fuselage
2x Chrome without rivets ( same area as above)
8x Chrome vent holes for vents on the very front of the nose
2x Spektrum stickers
2x Jet Cat stickers
the above can be changed by request
200 Chrome rivets
40 smaller chrome rivets that will work for the rivets around the apu exhaust on rear side of fuselage and if you want to they also look good going down the side of the intakes.
As well as lots of lengths of 3mm black trim line that when applied to the line between yellow and white really makes that contrast stand out.
All in all I spend an entire evening on just the appearance of the model. Between the T cut, polish and sticker application. I really do think this is a worthwhile exercise as it transforms the model.
The equipment list of what I have used in the model is as follows.
Jet Cat P-80 Se
JR 8411 x 5. Ail. Flap and rudder JR super servo horns on flaps. After market longer horns on Rudder and ailerons to get throw ( These were one hole longer than JR horns)
JR 3201 x 2 Stab with JR super servo horns to get movement required.
Hitec 645 steering
Spektrum 12100 Power safe Receiver
Airpower EV5u multi valve and sequencer
I changed my door rams to BVM 3" stroke ( Mains only. nose is stock)
3300 Mah Jet Cat Lipo for ECU
2x 2500 AA size Nimh 6volt RX packs. All bats in the nose section either side of nose retract bearers.
Dubro 40 Oz tank as secondary Tank
UAT ( or equivalent)
BBI/ Dragon Pilot in front seat only .
We are currently working on a really professional set of wing bags for the 2M. They will be a smaller set of what we have already for the Big Viper jet and go along way to helping protect your pride and joy. I will update when these are available.
Sorry to waffle on, but these are things I have picked up from my experiences and I hope they may help new or possible VJ2M customers. If you have any questions then please feel free to email me directly on [email protected]
I will try to follow up soon with some photos of various things on my 2M as well as an accurate centre of gravity and what control throws that I am using.
Read more: http://www.rcuniverse.com/forum/m_96...#ixzz0rlcgAOWY
#11
Since i'm looking at putting some of the same equipment in my v2m i thought i'd have a look at the weight difference of standard vs bling
Air System<div></div><div></div><div style="margin-left: 40px;">Standard system
2x Dual action valves : 72g
1x single action valve : 25g
Sequencer : 15g
2x air gauges : 30g
Total : <u>142g</u>
Bling System
<font face="arial,helvetica,sans-serif" style="font-size: 10pt;">EVSD-5U-Evo</font> : 145g
2x fill valves : 10g
Total : <u>155g</u></div><div>RX</div><div style="margin-left: 40px;">Standard System
Powersafe RX : 35g
Bling System
Pbox inc lcd and switch: 260g</div><div>
So to sum up, if you go for the bling airsystem then you are 13gheavier over standard but at the same time you simplify the install immensely. However if you decide to go with the powerbox then its a heftier 225g which is about the weight of a decent battery. Bear in mind I assumed above that you will connect the batteries direct to the rx and not have a switch or a reg
</div>

Air System<div></div><div></div><div style="margin-left: 40px;">Standard system
2x Dual action valves : 72g
1x single action valve : 25g
Sequencer : 15g
2x air gauges : 30g
Total : <u>142g</u>
Bling System
<font face="arial,helvetica,sans-serif" style="font-size: 10pt;">EVSD-5U-Evo</font> : 145g
2x fill valves : 10g
Total : <u>155g</u></div><div>RX</div><div style="margin-left: 40px;">Standard System
Powersafe RX : 35g
Bling System
Pbox inc lcd and switch: 260g</div><div>
So to sum up, if you go for the bling airsystem then you are 13gheavier over standard but at the same time you simplify the install immensely. However if you decide to go with the powerbox then its a heftier 225g which is about the weight of a decent battery. Bear in mind I assumed above that you will connect the batteries direct to the rx and not have a switch or a reg

</div>
#12
Thread Starter

My Feedback: (30)
John did advise me against the ev5u..The problem was I already had it, bought it with the kit. Now I am definitely contemplating it. John, plus some of the threads I see say the ev5u sees a lot of problems..If the powerbox, and ev5u adds that much more..That might have to go also.I will be talking with John today and getting his thoughts...Thank God for the classifieds...
I did see the orange viper you did, Beautiful job, Beautiful jet...

I did see the orange viper you did, Beautiful job, Beautiful jet...
#15
I think it was either duncan or alex that said that the problems they were having was due to water getting into the system so they added a water trap to their compressor and that solved the problem.
I am going to use the ev5u in my viper along with a powerbox royal 12k as i got one for a couple of hundred off the new price. The extra weight will be accounted for in battery size and choice (a123s in my case) along with the positioning of the unit to allow for cg issues. Over and above what has already been discussed here I will be putting in a smoke system (jetcat) which in addition to the pump will add more weight d/t to the smoke tank. Still, if I want it light(er) I won't fill the smoke tank.
Speaking about smoke pumps, I wouldn't buy a jetcat one until they sort out their electronic issues as mine (which was my second) has been with them since the beginning of june and have been told that it'll be at least another 2-3 weeks before I get it back. Here's hoping they find the problem with the units!
I am going to use the ev5u in my viper along with a powerbox royal 12k as i got one for a couple of hundred off the new price. The extra weight will be accounted for in battery size and choice (a123s in my case) along with the positioning of the unit to allow for cg issues. Over and above what has already been discussed here I will be putting in a smoke system (jetcat) which in addition to the pump will add more weight d/t to the smoke tank. Still, if I want it light(er) I won't fill the smoke tank.
Speaking about smoke pumps, I wouldn't buy a jetcat one until they sort out their electronic issues as mine (which was my second) has been with them since the beginning of june and have been told that it'll be at least another 2-3 weeks before I get it back. Here's hoping they find the problem with the units!

#16
Does this include the servos to actuate the valves in the "non-bling" setup?
The EVSD-5U doesn't need servos since its all electronic.
The EVSD-5U doesn't need servos since its all electronic.
ORIGINAL: reaps
Since i'm looking at putting some of the same equipment in my v2m i thought i'd have a look at the weight difference of standard vs bling
Air System<div> </div><div> </div><div style=''margin-left: 40px;''>Standard system
2x Dual action valves : 72g
1x single action valve : 25g
Sequencer : 15g
2x air gauges : 30g
Total : <u>142g</u>
Bling System
<font face=''arial,helvetica,sans-serif'' style=''font-size: 10pt;''>EVSD-5U-Evo</font> : 145g
2x fill valves : 10g
Total : <u>155g</u></div><div>RX</div><div style=''margin-left: 40px;''>Standard System
Powersafe RX : 35g
Bling System
Pbox inc lcd and switch : 260g</div><div>
So to sum up, if you go for the bling airsystem then you are 13gheavier over standard but at the same time you simplify the install immensely. However if you decide to go with the powerbox then its a heftier 225g which is about the weight of a decent battery. Bear in mind I assumed above that you will connect the batteries direct to the rx and not have a switch or a reg
</div>
Since i'm looking at putting some of the same equipment in my v2m i thought i'd have a look at the weight difference of standard vs bling

Air System<div> </div><div> </div><div style=''margin-left: 40px;''>Standard system
2x Dual action valves : 72g
1x single action valve : 25g
Sequencer : 15g
2x air gauges : 30g
Total : <u>142g</u>
Bling System
<font face=''arial,helvetica,sans-serif'' style=''font-size: 10pt;''>EVSD-5U-Evo</font> : 145g
2x fill valves : 10g
Total : <u>155g</u></div><div>RX</div><div style=''margin-left: 40px;''>Standard System
Powersafe RX : 35g
Bling System
Pbox inc lcd and switch : 260g</div><div>
So to sum up, if you go for the bling airsystem then you are 13gheavier over standard but at the same time you simplify the install immensely. However if you decide to go with the powerbox then its a heftier 225g which is about the weight of a decent battery. Bear in mind I assumed above that you will connect the batteries direct to the rx and not have a switch or a reg

</div>
#18
Thread Starter

My Feedback: (30)
Well I just got off the phone with John and as recommended to me before, I am going to get rid of the powerbox and the 921 and go with a 1222...I do want to save weight, the issue I was having is that I already had the receiver and powerbox. So if anyone needs some cheap new stuff...
I do believe Ali's wing bags accommodate the wing tips..

I do believe Ali's wing bags accommodate the wing tips..
#23
Well, if you really want to save weight, get rid of the P-80SE and get yourself a Cheetah or Merlin 90. You'll save nearly 2 lbs between the lighter engine and lighter accessory kit + less fuel to carry.
The Merlin 90/Cheetah offers exactly the same performance level than the P-80SE and is 20% lighter ( with 5 minutes of fuel )...
The Merlin 90/Cheetah offers exactly the same performance level than the P-80SE and is 20% lighter ( with 5 minutes of fuel )...
#24
Obviously the guy has already bought the P80 and the 8411s, 8711s and the metal arms. There is NOTHING wrong with using these items on this jet. This jet is 76" long and has a 79" wing, this thing isn't that "baby sized if you ask me. The elevator is 14" long and 2.5" wide. Thats a big elevator. The alerons are 14" x 4" and the flaps are 13" x 4". I would like to see Oli's stats on these.


