Viper Jet 2M Pointers/ tips.
02-24-2015 | 05:01 AM
#526
Another idea Danno.
As you know the Viper comes in tail heavy so you need as much weight forward as you can.
What I did was cut the inside of the intake ducting, mount the turbine as far forward as possible (to assist cg), mount the pipe wherever it needs to go, then cut the end off the fibreglass tail cone so it's only 10mil longer than the pipe. I think I cut 30mil off the pipe. The result is my Viper is balanced perfect with no lead anywhere, and you can't tell the difference. It also enlarges the gap at the back for hot air to escape as the standard set up is very cramped.
As you know the Viper comes in tail heavy so you need as much weight forward as you can.
What I did was cut the inside of the intake ducting, mount the turbine as far forward as possible (to assist cg), mount the pipe wherever it needs to go, then cut the end off the fibreglass tail cone so it's only 10mil longer than the pipe. I think I cut 30mil off the pipe. The result is my Viper is balanced perfect with no lead anywhere, and you can't tell the difference. It also enlarges the gap at the back for hot air to escape as the standard set up is very cramped.
LOL Thanks for the response, I keep ya posted.Cheers,
Dan
Last edited by rcjetsaok; 02-24-2015 at 11:43 AM.
01-12-2016 | 10:16 PM
#528
Don't know if anybody has a need or not, but, end of the season I pancake in my 2M Viper due to a flame out. Fuselage and wings weren't useable so I am on to the next plane. Anyway, I have a few parts and pieces if anybody needs anything.
Rudder, Elevator/Stabs are in great shape. I even have a replacement Rudder that has never been mounted all in the British anniversary scheme.
Retracts are great. Thrust tube, bellmouth and tailcone are undamaged. Canopy and cockpit are fine. Wingtube is good.
If anybody needs anything send me a PM and I'll see if I can help.
Rudder, Elevator/Stabs are in great shape. I even have a replacement Rudder that has never been mounted all in the British anniversary scheme.
Retracts are great. Thrust tube, bellmouth and tailcone are undamaged. Canopy and cockpit are fine. Wingtube is good.
If anybody needs anything send me a PM and I'll see if I can help.
01-28-2016 | 03:14 AM
#529
i know this is an old thred but i want to thank you for taking the time to review the VJ2M. i just picked up a NIB one from a friend and i have to say that i'm really impressed with how it goes together down to the paint. it has some of the nicest paint i have seen on an arf. I'd really like to see pics of yours done up in the updated marking . thanks again,WB_1
02-06-2016 | 05:29 PM
#530
Another heads up guys....
My builders put their own 2M together last week ( First from the latest batch with mods) They flew it at the weekend with everything going as per all the VJ's so far.
Things noted were..
The factory have made the tailpipe longer. This means you can mount the turbine further forward thus eliminating the need for any nose weight. My builders seem to believe that it might now be slightly too long for a P-80Se install. It was an easy job to trim it down, and a much better option than adding weight to the nose.
The really good news is that they report the new gear door cylinder placement has worked perfectly. With no mods to the standard kit they had 4 flights with no opening of the doors even during quite aggressive pulls.
They did mention that after shut down they found allot of excess heat building in the top of the fuselage ( Above turbine ) Enough for them to get worried about the well being of the fibre glass. They added some heat shield but it was still getting hot. They got round it by adding half a bypass to direct air out. I have to say that my two have not had this bypass fitted and I cant say i have ever noticed mine getting hot at all, but I will look into it better on the next run.
I hope this helps? If I find anything else out I will update this thread.
Regards Al
My builders put their own 2M together last week ( First from the latest batch with mods) They flew it at the weekend with everything going as per all the VJ's so far.
Things noted were..
The factory have made the tailpipe longer. This means you can mount the turbine further forward thus eliminating the need for any nose weight. My builders seem to believe that it might now be slightly too long for a P-80Se install. It was an easy job to trim it down, and a much better option than adding weight to the nose.
The really good news is that they report the new gear door cylinder placement has worked perfectly. With no mods to the standard kit they had 4 flights with no opening of the doors even during quite aggressive pulls.
They did mention that after shut down they found allot of excess heat building in the top of the fuselage ( Above turbine ) Enough for them to get worried about the well being of the fibre glass. They added some heat shield but it was still getting hot. They got round it by adding half a bypass to direct air out. I have to say that my two have not had this bypass fitted and I cant say i have ever noticed mine getting hot at all, but I will look into it better on the next run.
I hope this helps? If I find anything else out I will update this thread.
Regards Al
02-07-2016 | 02:40 AM
#531
air tray - all in one
savox low profile 9-10kg servo fittet into horizontal stab
air tanks were located under the turbine mount
1 pic loaded bu ,istake - has n relevance - cant find a way to delete it
02-07-2016 | 03:38 AM
#532
Izzy, can you tell me what the number of the savox' servos on the elevators are ?
02-09-2016 | 04:23 AM
#533
SB2261
below is the link to the servo - zero play - but you need to rebuild the housing
also make sure to change the geometry such that the horn will be 90 degrees to the hinge line
skymaster glued the servo mounts wrong, and if you keep it that way , you need to use ball joints to make up for the mistake
( ask me how i know - i built mine, and fixed the others that i built for friends ) http://www.savoxusa.com/product_p/savsb2261mg.htm
below is the link to the servo - zero play - but you need to rebuild the housing
also make sure to change the geometry such that the horn will be 90 degrees to the hinge line
skymaster glued the servo mounts wrong, and if you keep it that way , you need to use ball joints to make up for the mistake
( ask me how i know - i built mine, and fixed the others that i built for friends ) http://www.savoxusa.com/product_p/savsb2261mg.htm
02-09-2016 | 05:17 AM
#534
SB2261
below is the link to the servo - zero play - but you need to rebuild the housing
also make sure to change the geometry such that the horn will be 90 degrees to the hinge line
skymaster glued the servo mounts wrong, and if you keep it that way , you need to use ball joints to make up for the mistake
( ask me how i know - i built mine, and fixed the others that i built for friends ) http://www.savoxusa.com/product_p/savsb2261mg.htm
below is the link to the servo - zero play - but you need to rebuild the housing
also make sure to change the geometry such that the horn will be 90 degrees to the hinge line
skymaster glued the servo mounts wrong, and if you keep it that way , you need to use ball joints to make up for the mistake
( ask me how i know - i built mine, and fixed the others that i built for friends ) http://www.savoxusa.com/product_p/savsb2261mg.htm
02-09-2016 | 05:20 AM
#535
another thing that bothers me about the elev. servos is them wanting you to mount them so that you have to open up the stab root the the fuse side for servo bottom clearance. i was thinking about mounting them conventionally but i'm concerned about the control horn being so close to the root of the elevator control surface.
02-09-2016 | 07:56 AM
#536
another thing that bothers me about the elev. servos is them wanting you to mount them so that you have to open up the stab root the the fuse side for servo bottom clearance. i was thinking about mounting them conventionally but i'm concerned about the control horn being so close to the root of the elevator control surface.
if you mount the servos as i dod you do not need to open up the root of the stab at the fuselage end , in fact , i made it so that the stabs are removable , and makes transportation easy
i will upload pics later tonight of mods i did
02-14-2016 | 02:04 AM
#537
as you can see had to open up a bit the servo mounts quite a bit and then made new servo mounts plates - glued with hysol to the spar and stab joiner
now it also works nice as the angles are correct
the savox servo is amazing - srong and zero slop
03-05-2016 | 05:26 AM
#539
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Just got done reading this hole thread.Now I am bummed because I just purchased the new jc rabbit 100se @ 24lbs of thrust.First turbine but seems its not going to be very acrobatic but more scale that will nife edge and looks like I may have some cg issues.I should of read this first instead of what sales men recommend.2700 dallar face palm.
03-05-2016 | 05:38 AM
#540
Just got done reading this hole thread.Now I am bummed because I just purchased the new jc rabbit 100se @ 24lbs of thrust.First turbine but seems its not going to be very acrobatic but more scale that will nife edge and looks like I may have some cg issues.I should of read this first instead of what sales men recommend.2700 dallar face palm.
03-05-2016 | 11:54 AM
#541
I fly mine with a Jetcat P100 and I am quite happy with the performance
https://www.youtube.com/watch?v=u8X_IgWggFQ
https://www.youtube.com/watch?v=u8X_IgWggFQ
03-05-2016 | 02:59 PM
#543
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I purchased the turbine before my email to skymaster no worries your opinion was not miss lead.I normally over power all my models for my style of flying just to have thrust on reserve.Something I can pull into a harrier and have enouph thrust to pull out of it before stalling.1:1 thrust to weight with fuel.Keeping it light it should be a great flying first jet.
Has any one tried any thrust vectoring for this model.I know its not a 3d model but should open up the flight envelope.
https://youtu.be/uioXwlDrN4E
Last edited by Ash Creek Flier.; 03-05-2016 at 03:16 PM.
03-06-2016 | 01:40 AM
#544
100N turbine will be great on this model - more than enough power
here a link of a good flying bud , and the secret is to keep it light
https://www.youtube.com/watch?v=Az0CES8D4kM
here a link of a good flying bud , and the secret is to keep it light
https://www.youtube.com/watch?v=Az0CES8D4kM
03-06-2016 | 11:58 AM
#545
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Thanks guys for the video.Big confidence booster.For what this cost I was freaking out a little and possibly over thinking it.Still planning things in the long run.Still a little worried about cg for as far forward I see a lot of people mounting there turbines and the jc rabbit is only 2.2 lbs but will figure it out when I get that far.Extra juice on batteries more than likely.
What do you guys think as far as fuel tanks.Is it worth spending the extra for glassed kevlar will they rupture just the same in the event of a crash as the supplied tanks.
What do you guys think as far as fuel tanks.Is it worth spending the extra for glassed kevlar will they rupture just the same in the event of a crash as the supplied tanks.
03-06-2016 | 03:15 PM
#546
Thanks guys for the video.Big confidence booster.For what this cost I was freaking out a little and possibly over thinking it.Still planning things in the long run.Still a little worried about cg for as far forward I see a lot of people mounting there turbines and the jc rabbit is only 2.2 lbs but will figure it out when I get that far.Extra juice on batteries more than likely.
What do you guys think as far as fuel tanks.Is it worth spending the extra for glassed kevlar will they rupture just the same in the event of a crash as the supplied tanks.
What do you guys think as far as fuel tanks.Is it worth spending the extra for glassed kevlar will they rupture just the same in the event of a crash as the supplied tanks.
03-06-2016 | 10:57 PM
#548
the kevlar tanks are not that great if you ask me , they have a very terrible seam for the top tank that the clunk has a hard time to deal with
as far as mounting the turbine , i would mount it as far forward as you possible can , to avoid adding extra weight ( be it lead or larger batteries )
keep it as light as you possible can.
try mount everything as far forward too
the merlin 100 is a light turbine , so that really helps with the weight issue
as far as mounting the turbine , i would mount it as far forward as you possible can , to avoid adding extra weight ( be it lead or larger batteries )
keep it as light as you possible can.
try mount everything as far forward too
the merlin 100 is a light turbine , so that really helps with the weight issue
03-07-2016 | 02:02 PM
#549
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From: milduravictoria, AUSTRALIA
Hi Guys, No disrespect to Izzy,but he is wrong about the elevator horn. The way he has it is the link pivot point is a long way behind the hinge point ( which is " live" hinged),this makes the throws unequal without adjusting the ATV and this adjustment,in turn, means the travel above and below the hinge is not a normal curve. This creates all sorts of mechanical/throw issues. You may never notice this, but look at the trouble the Pattern guys go take to avoid these issues. Sorry I'm a purist coming from pattern to jets.
Cheers.
Cheers.
