Q-500 Racing Discuss AMA 428, AMA 424, and any other variants of Quickie 500 racing

Viper Q500 tips and techniques

Reply
Old 06-23-2008, 10:53 AM
  #1
daven
Thread Starter
 
Join Date: Dec 2001
Location: Waseca, MN
Posts: 8,455
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Viper Q500 tips and techniques

Use this thread to discuss building and flying tips and techniques in regards to the Great Planes Viper Q500. I'll pull some older posts and move them in here to keep them together.
daven is offline  
Reply With Quote
Old 06-23-2008, 11:31 AM
  #3
daven
Thread Starter
 
Join Date: Dec 2001
Location: Waseca, MN
Posts: 8,455
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

I grabbed this out of a long thread, lots of good info here.

Some of the recommended mods for the Predator that I remember (probably apply to the Viper as well) are:
1)Drill holes through the fuse into the hold-downs through the fuselage and pin them with epoxy covered round toothpicks. You should also do the same thing with the landing gear plate. Add some fiberglass or carbon fiber re-inforcement to the firewall area if you think it needs it.

2)Place a piece of 3/8" triangle stock under the wing hold downs and glue well.

3)Re-Tap the metric wing hold downs to 1/4-20 for ease of replacement. Before you do, check the wing alignment by triangulating to make sure it's square to the fuse and not sqewed. If it's off you can correct it when you re-tap by epoxing dowels in some of the holes and redrilling an tapping. The 1/4-20 bolts are easier to come by if you lose one. (Only Ed Smith has metric stuff in his box )

4)Mix epoxy and micro balloons and make a fillet between the wing hold-downs and the fuselage. How to techniques is somewhere in this forum.

5)Change the torque rods in the ailerons, especially if you're planning a really strong engine. The change is easy. Simply cut down both sides of the torque rodsabout 1/8" wide and lift the piece out to expose the torque rod. Remove the 2mm torque rods and replace them with one bent from a 4-40 Dubro threaded rod bent to the same dimensions that the 2mm were bent. Put them in the slot and put the 1/8" piece back in the slot. Press it down on the new rod and Ca it in place with thick Ca. Do not glue the 4-40 rod. Carefully drill the holes in the ailerons to 3/32. Install ailerons as instructions.

6) Check the finished airplane for lateral balance as well as for correct CG.

7) Want more? Instead of bringing the wood pushrods out the top of the fuselage, Darrol Cady suggests the following Darrol Cady mods.

Sharpen a piece of1/8" brass tubing and use it to cut holes in the side of
the fuse under the stab on the angle that the pushrods would exit the fuse.
Use two pieces of Dubro 4-40 threaded rod to make control horns that fasten
to the elevators and go to the bottom. Bend them so that they are about 1/8"
from the side of the fuse and run free for their arch. Then make up carbon
PushRods with the 2-55 threaded rod long enough to go through and exit the
fuselage. Install ball links on the control horns and attach the PushRod.
The extra that you cut off the 2-56 threaded rod should be glued into the
other end of the PushRod and made to a Z bend to attach to the servo.

There may be others, but that's what I remember. Also see these threads:
http://www.rcuniverse.com/forum/m_11...tm.htm#1120726
http://www.rcuniverse.com/forum/m_11...tm.htm#1141469


Stan Douglas
daven is offline  
Reply With Quote
Old 06-23-2008, 11:55 AM
  #4
Super Splatter
 
Super Splatter's Avatar
 
Join Date: Mar 2006
Location: , MN
Posts: 432
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

throw the wheels away, dig out the inside so you can put a jett tank in it, add more glue to the firewall area, glue the front hatch on, shim the tail , and don't put a LS on it.
Super Splatter is offline  
Reply With Quote
Old 07-13-2008, 03:43 PM
  #5
russm
 
Join Date: Aug 2006
Location: peoria, AZ
Posts: 470
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

thanks davin, nice job and needed
russm is offline  
Reply With Quote
Old 07-13-2008, 06:16 PM
  #6
vicman
 
vicman's Avatar
 
Join Date: Dec 2002
Location: Valdese, NC
Posts: 9,907
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

Got some reading to do...Thanks.
My Viper took the .25 FX great and was a race winner that way but has gotten totally screwy with the TT.40. Only when it gets up to speed, otherwise flies perfect.
vicman is offline  
Reply With Quote
Old 08-02-2008, 02:48 AM
  #7
freeair
 
Join Date: May 2008
Location: queensland, AUSTRALIA
Posts: 891
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

i am thinking of buying a viper and fitting a near new o.s. 46 ax engine, any tips that i need to know without looking through heaps of posts ? thanks.
freeair is offline  
Reply With Quote
Old 08-02-2008, 09:01 PM
  #8
vicman
 
vicman's Avatar
 
Join Date: Dec 2002
Location: Valdese, NC
Posts: 9,907
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

My problem ended up being the Rx. After a swap all my problems went away and it flies like it should.
vicman is offline  
Reply With Quote
Old 08-02-2008, 09:52 PM
  #9
PhilMill
 
Join Date: Jun 2008
Location: Clermont, FL
Posts: 80
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

Bought a new Viper on Monday....Apparently they've changed it quite a bit....

Firewall is strengthened with trangle stock, landing gear block too, blind nuts for the motor mount are installed, the rear hatch is longer , longer servo tray with a place for the receiver and battery with velcro hold downs, wing hold downs are reinforced, the wings have different flatter longer sleeker wing tips, landing gear is painted to match the white plane, it has pizza cutter wheels instead of those plastic poker chips, the nose is glassed inside and outside for added strength, they installed gray plastic push rod tubes,couple other things....Looks like they did a better job on these new ones...

But they still have the fuel tank in the nose..I had to wallow out the front former a bit to make room for a Tetra tank on the CG...

Used mini servo's and a micro on the throttle - she weighs 3 lbs 12 ounces on the nose...

Nice plane, Gonna fly her tommorrow with a TT40 and then switch to a Jett 40 if she flys okay.....Maybe I'll strap on a Nelson short stroke...
PhilMill is offline  
Reply With Quote
Old 08-02-2008, 11:22 PM
  #10
Bozarth
 
Join Date: Apr 2004
Location: Aurora, CO
Posts: 1,284
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

The changes you mentioned have been in effect for almost 1 1/2 years. Good notes though! They fly very well.

Kurt
Bozarth is offline  
Reply With Quote
Old 08-03-2008, 05:43 PM
  #11
PhilMill
 
Join Date: Jun 2008
Location: Clermont, FL
Posts: 80
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

Really Bozarth? I had no idea, this is my first Viper....Got a bunch of Predators.....

Took her out for a trim flight today and it was a handful...It kept trying to dive into the ground.....Holding full elevator to get her down...

Shimmed the tail a bit, took her up again...better but not quite......Shimmed the tail a bunch more, finally got her flying straight and level with just a tiny bit of trim...Ailerons were great.....Now I gotta make some more permanent type shims and fly her again. Then ,maybe I'll epoxy the tail on when I'm happy with it.....Had no idea that it could be so far off when the tail was sitting perfectly in the saddle.....Hmmmmm Well, they're mass produced so I guess there are some drawbacks...

Flew my new Ninja today a couple times....Boy it's nice when you put together a race plane and all it takes is a click or two here and a click or two there and it flies perfect.....A little more "dialing in" and it'll be ready to race....Yeah for the composites....
PhilMill is offline  
Reply With Quote
Old 08-04-2008, 03:02 AM
  #12
Bozarth
 
Join Date: Apr 2004
Location: Aurora, CO
Posts: 1,284
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

Philmill,

I'll trade you one of my Vipers for your Ninja. I'll even pay for the shipping. Honest. Really. I'm serious.

Kurt
Bozarth is offline  
Reply With Quote
Old 08-04-2008, 09:59 AM
  #13
PhilMill
 
Join Date: Jun 2008
Location: Clermont, FL
Posts: 80
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

Hey Kurt, Viper for a Ninja? Heck, I've got 2 of em...

Yea okay.....Shipping will be around a thousand dollars though...!!!!!!!!!!!!!!!!!LOL

Phil
PhilMill is offline  
Reply With Quote
Old 12-29-2008, 11:36 PM
  #14
freeair
 
Join Date: May 2008
Location: queensland, AUSTRALIA
Posts: 891
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

another needed mod to the Viper . [ V- TAIL ] remove the center top block on the V-tail then remove about 2 inches of covering from both tail halves , top and bottom. add a 3 to 4 inch piece of light fibreglass cloth with epoxy or resin to the top and bottom surfaces. i say to do this as for no particular reason other than a poor build / glue job from factory my V-Tail halves separated , luckily the model was on the ground with engine idleing before take off.
freeair is offline  
Reply With Quote
Old 12-30-2008, 06:36 AM
  #15
s. wallace
 
Join Date: Feb 2002
Location: Endicott, NY
Posts: 782
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques


Quote:
ORIGINAL: freeair

another needed mod to the Viper . [ V- TAIL ] remove the center top block on the V-tail then remove about 2 inches of covering from both tail halves , top and bottom. add a 3 to 4 inch piece of light fibreglass cloth with epoxy or resin to the top and bottom surfaces. i say to do this as for no particular reason other than a poor build / glue job from factory my V-Tail halves separated , luckily the model was on the ground with engine idleing before take off.
Probably a very good idea, a guy that races in our series had the same failure, but while racing. The resulting damage was repairable but post crash inspection showed the V-Tail glue joint was almost dry, very little evidence of glue. He was really in a sense lucky the model wasn't totalled.
s. wallace is offline  
Reply With Quote
Old 12-30-2008, 09:15 AM
  #16
Giant
 
Join Date: Sep 2002
Location: HOBE SOUND, FL
Posts: 74
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

Good Idea, I've had two Viper tail failures in the past year with the total loss of both aircraft. Now I always reinforce with fiberglass or just build another tail. After the second failure I sent the remains back to Tower and they replced it free of charge. A good company.
Giant is offline  
Reply With Quote
Old 01-24-2009, 09:36 PM
  #17
ScaleSpeedShop
 
Join Date: Sep 2006
Location: Wichita, KS
Posts: 12
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

Here's a motor brace we made for the nose of the viper. It's made from .012 Aluminum Flashing that you can get at your local hardware store.
Attached Thumbnails
Click image for larger version

Name:	Tr51260.jpg
Views:	293
Size:	33.4 KB
ID:	1118687   Click image for larger version

Name:	To43717.jpg
Views:	296
Size:	24.0 KB
ID:	1118688   Click image for larger version

Name:	Lq39025.jpg
Views:	256
Size:	19.3 KB
ID:	1118689   Click image for larger version

Name:	Ic85321.jpg
Views:	270
Size:	21.8 KB
ID:	1118690   Click image for larger version

Name:	Ep86033.jpg
Views:	371
Size:	29.8 KB
ID:	1118691   Click image for larger version

Name:	Kb43977.jpg
Views:	268
Size:	26.4 KB
ID:	1118692   Click image for larger version

Name:	Qs29296.jpg
Views:	242
Size:	24.0 KB
ID:	1118693   Click image for larger version

Name:	Gf19097.jpg
Views:	256
Size:	26.0 KB
ID:	1118694  

Click image for larger version

Name:	Tr20170.jpg
Views:	243
Size:	28.4 KB
ID:	1118695   Click image for larger version

Name:	Vh46138.jpg
Views:	238
Size:	22.6 KB
ID:	1118696  
ScaleSpeedShop is offline  
Reply With Quote
Old 01-25-2009, 12:32 AM
  #18
freakingfast
 
Join Date: Jan 2005
Location: Mather, CA
Posts: 2,222
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

The most important thing you can do for the firewall is epoxy down the fuel hatch cover. Don’t screw it down. Even better, replace the balsa cover with glued down aircraft plywood. Remove the covering material in the glued area on all 4 edges for 100% contact. This forms a very strong box structure VS a channel. . Its funny how may people want easy accesses to the tank and ignore the instructions, I can’t blame them.


The second reason that the firewalls fail is that some guys spin up the starter, than slam it into the spinner nut sometimes misaligned, shaking the heck out of the poor plane.
Back the prop off compression so you get some momentum, line up the starter on the spinner and push the switch....much less violent.


Pictured, is a new in-box fuselage with the tail pre-broken. I removed the covering around the area applied medium CA in the crack and held it closed than carbon fiber strips were added high on each side and one on the bottom.
Attached Thumbnails
Click image for larger version

Name:	Rp44791.jpg
Views:	240
Size:	59.7 KB
ID:	1118848  
freakingfast is offline  
Reply With Quote
Old 01-31-2009, 01:09 AM
  #19
freeair
 
Join Date: May 2008
Location: queensland, AUSTRALIA
Posts: 891
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

i must say very nice job on the motor brace but having only 2 fixing points [ rivets ] is not enough. if this was made in a box type section and fitted with say 4 x rivets [ 2 top and 2 bottom the strength would be much better. with the latest model Vipers they have added fibreglass cloth around the front and side outer fuse engine area plus f/glass to the inner mount and tank bay, what i now do for more strength is epoxy the front top hatch on then pin all 4 sides with 2 x 1/8th cane squers [ total 8 ] then finish with a wrap of light glass cloth , this has proven great strength with running Profi and Nelson engines from other club members .
freeair is offline  
Reply With Quote
Old 03-10-2009, 08:53 AM
  #20
DMyer
 
Join Date: Oct 2002
Location: Potomac, MD
Posts: 642
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

To stiffen the Viper front end I always add triangle stock to all the front end corners where it is missing including the top hatch. I sand off the covering on the front firewall and make up a 1/8 front plate of good 5-6 ply aircraft grade plywood slightly larger than the existing firewall. I use the backplate mount as a pattern to drill out the mounting holes - and then apply slow cure epoxy to the firewall and bolt on the new 1/8 front firewall plate between the old firewall and the motor mount and let cure. The exisitng firewall is too soft IMO and the new quality 1/8 plate gives the motor a much better seat. You also gain some firewall glue area as the new plate contacts the fuse 4 fuse sides at the front. I replace the top hatch with a solid piece of plywood - no window needed and glue on with epoxy. I next drill three holes through each fuse side into the the motor mount and epoxy tooth picks or small dowls. These mods take a couple hours work at most and add a ton of stiffness to the front end as well as making as stiff a mount as possible on the VIPER for the motor to produce all the HP it is capable of. One last thing is that the GP motor mount is a very soft alloy - I prefer using a good Nelson backplate mount.




dan
DMyer is offline  
Reply With Quote
Old 03-10-2009, 08:56 AM
  #21
tIANci
 
tIANci's Avatar
 
Join Date: Jan 2004
Location: Kuala Lumpur, MALAYSIA
Posts: 10,489
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

The new batch of Vipers have f/glass on the inside and outside of the firewall. Its still not that strong enough. I needs to be beefed up. Mine just started to peel off. I opened it all up and find that the fibreglass is nonsense, is not flush in the corners. The balsa tri stock comes off with ease. Time to remove it all and fix her up again.
tIANci is offline  
Reply With Quote
Old 08-19-2009, 01:29 PM
  #22
vertical grimmace
 
vertical grimmace's Avatar
 
Join Date: Mar 2004
Location: ft collins , CO
Posts: 7,158
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

One nice thing with the new ARC Viper is all of these mods can be done without having to pull off the covering. What a great offering from Great planes. We use these in local 428 as well but they do need some strengthening here and there. I did have a wing blow off with the Nelson on it. The wing mounts probably need to be looked at as well.
As for electric starter damage, at least for 424, I start mine by hand. I am a CL flyer though and electric starers are not only hard on airframes but engines as well when not properly used.
vertical grimmace is offline  
Reply With Quote
Old 08-19-2009, 03:44 PM
  #23
fizzwater2
 
Join Date: Aug 2004
Location: Paola, KS
Posts: 2,724
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

Freakingfast - does it help to have a Cat scan of the fuselage? The cat in your picture sure looks unhappy at the break!

fizzwater2 is offline  
Reply With Quote
Old 09-07-2009, 11:48 PM
  #24
freakingfast
 
Join Date: Jan 2005
Location: Mather, CA
Posts: 2,222
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

Good one! Cat scan
I no longer work on planes in the house because of the dang cats, and I can't take the CA fumes or the balsa dust in the house either. One cat zipped open a wing chasing a fly and another 17lbs kitty stepped on a wing and punched a hole through the sheeting.

I now work in the garage only, no nosy cats to get into things there.
Attached Thumbnails
Click image for larger version

Name:	Nl29428.jpg
Views:	115
Size:	145.7 KB
ID:	1270943  
freakingfast is offline  
Reply With Quote
Old 09-08-2009, 04:44 AM
  #25
GSJames
 
GSJames's Avatar
 
Join Date: Nov 2003
Location: Weatherford, TX
Posts: 566
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Viper Q500 tips and techniques

There are lots of funny pictures of cats, dogs etc doing funny things with amusing captions at:

http://icanhascheezburger.com/

The "CAT scan" photo would make a good addition
GSJames is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 03:38 PM.