Avistar assembly question
 

I'm almost to the step where I have to epoxy the two wing halves together. The instructions say only to put epoxy into the wing joiner cavity and the joiner itself, NOT to the inside surface of the two wing halves.

Am I supposed to put epoxy on the inner surface of the wings where they go together? Otherwise, the only thing holding the wings together will be the epoxy just on the wing joiner.

Thanks.

RE: Avistar assembly question
 

Pete1burn... It's been a few years since I put mine together, and it's still together...
But I epoxied all the surfaces... It may not be needed, but I also glassed the wing
joint... I have put a ton of flights up til this day, and loads of stress... And she's still
hanging together to tis day, just about 3 yrs later and 250+ flights

I only glassed the bottom of the wing... Sorry... Here's some pics..

RE: Avistar assembly question
 

Recently built mine about a month ago now. I glued ALL surafaces on the two wings. Its actually better to do this. In general, you should always do this so maybe the intructions just missed this one little point. I'd recommend to do it though.

RE: Avistar assembly question
 

Pete1burn,

I built my Avistar about 7 years ago and its still flying great. I'd recommend epoxying the inside surfaces together, this will add some extra strength to it. id use 30 minute expoxy for all the wing joining steps you mentioned. 30 minute is stronger, stands the test of time, and will allow you more time to clean up the excess epoxy that leaks out with rubbing alcohol. make sure not to flood the surfaces tho, a light coat will do :) also make sure you have equal portions of epoxy (very crucial) and use a throw away brush to spread it on with. Good luck with these steps, they always were the most nerve racking for me :D

RE: Avistar assembly question
 

Thanks for the replies. I was going to epoxy it anyway, but then I thought that there might be a reason for not epoxying it.

I stopped for the night before I got to that point. I'm gonna get some sleep and take a fresh look at everything tomorrow. Trying not to rush and make a mistake with my first build.

:D

RE: Avistar assembly question
 

Pete1burn,

When you epoxy the wing halves together, you want all the joining surfaces are well coated with at 30 minute epoxy. You want to make sure epoxy is down in the joiner cavity, on the joiner/dihedral brace, and on the center ribs. You also want to make sure you remove the covering from the rib faces to be glued - you want as much wood to wood joining as possible. Don't worry about excess epoxy running out since you can wipe that off with a paper towel wetted with alcohol.

When you join them, make sure the wing tips are parallel (no twist in the wing), then secure the wing with several pieces of tape to make sure it doesn't move around on you.

Hogflyer

RE: Avistar assembly question
 

Another couple of assembly questions:

Question on the aileron hinges. They are these octagonal fiber pieces with a slice through the long way.

1st, the image in the instructions (pg 7) show the hinges going in with the slice perpendicular to the wing, not parallel. Doesn't it make sense that the slice should be going horizontally so that the hinge can flex with the aileron movement?

Also, it says to wick 4 drops of CA into the hinges when installing them, but it also says there should be no gap between the ailerons and wings. If I am using CA in the hinges, won't that glue the aileron to the wing?

Thanks in advance.

Pete

RE: Avistar assembly question
 

Hey Pete... IMO, your right on the hinges, and ite the way I installed mine... I installed my
ails as the book said althe way up against the T.E..... And it has worked fine and help up
to the test of time.... But... If I had to do it over, I would leave a very fine gap...
The CA will "stick" the two together somewhat.. But as your done CA'ing all, you need to flex
the ails and it should be no problems... You need to get the slots/area cleaned and flat.. I
also drilled a little hole in the center of the slots to get more CA down in there... Key... You
need enough CA..... But not too much so as to get the hinge to brittle... Good luck..

RE: Avistar assembly question
 

Well, the aileron assembly went fine. Everything went together great.

When I got the elevator, things got sticky. (Literally)

I test fit everything dry first and it all fit just fine. I put some drops of CA on one side of the hinges and pushed them into the elevator. Then I put some CA on the other side of the hinges and started pushing the elevator into the horizontal stab. The CA set almost instantly. I couldn't move the elevator anymore, and the two left hinges were set while the two right hinges were sticking in by a hair. I ended up getting out the farthest right hinge, but the 2 inner hinges were all messed up.

I had to cut the two inner hinges and glue in the far right hinge. So the elevator is sitting on only two hinges, on the far right and far left. Also, the elevator is off center by about 1/8 of an inch.

This CA is STRONG, so I don't think it will be a problem. There's also a small gap, but not big. I don't think it will affect anything in the long run. Do you guys think I should replace the whole horizontal stab, or will it be okay?

The rest of the assembly up until now has been a breeze. Part of why I was so surprised that it set so damn quickly on the elevator and I got the large ailerons in without a problem.

Attached a couple of pics. The first is a close up of the hinge, and the second is the elevator.

RE: Avistar assembly question
 

Pete1burn... On the hinges... your suppose to test fit all, get all adjusted and with the
hinge in both sides, adjusted and in place.. you then deflect and hold the control surface
up or down then add three or four drops of C.A. to each hinge, and repeat on the other
side.. not add ca then install the hinges... to ensure you have the hinge centered
equally in both half, you can stick a push pin in the center of the hinge before puttings
in both surfaces then c.aing... And when deflecting the surface, insure all stays in
alignment and that you do not pull the hinge out..

You may be ok as is??? It's hard to tell but but is the elev and stab even, not the off
center you were talking about , but even top and bottom front to back? it looks a bit off,
but it could be the deflection.. The only other thing I know to do is to cut the hinges at
the center, clean them(ends) up some and put new hinges on either side of the ones that
inplace... And just maybe you might be able to work them out???, but be very carefull if
you try, you donot want bulsa to come out with it because then the slot would be too big
for a CA hinge...

But you may be ok.. , But, then again I would question the amount of CA that got wicked
into the bulsa..... So it may be best to redo them??? IMO

Hope you understand what I'm trying to say.... I don't explain too good [:o]

RE: Avistar assembly question
 

Will it be ok? In one word or less, NO! Two hinges will not be enough to hold the elevator in flight, no matter how strong you think the CA is. You will need to cut the hinges free, cut new slots for the hinges in both the elevator and horizontal stab, and reassemble them correctly with new hinges. If you try to fly the plane like this you're more than likely going to bring it home in a bag.

The problem is that you did not attach the CA hinges properly. The hinges need to be IN PLACE in the both the stab and elevator before you apply CA to them. You can't put CA on them and then insert them, it just won't work. RCU member Minnflyer has written an excellent "how-to" on using CA hinges. Read it over before you continue on and see if it doesn't help you out. It can be found at:

[link=http://www.rcuniverse.com/magazine/article_display.cfm?article_id=55]CA Hinges How-to[/link]

Hope this helps

Ken

RE: Avistar assembly question
 

It will be virtuall impossible to put replacement hinges in the oribinal locations if there is debris in the holes(old hinges or CA build up) and that will be very hard to remove. Just plane on cutting the bad hinges and installing new hinges next to the original ones. Yes, not fun but needed.[:o]

RE: Avistar assembly question
 

BTW, the slits should have been perpendicular to the hinge line. The slit would have functioned much like the drill hole Raideron mentioned and allowed CA to wick deep into the hing pocket. The slit left a path (channel) for the CA to flow down.

RE: Avistar assembly question
 

the big reason why you can not use the old hing slots is that the cas has hardened the wood and any new ca will not wick into the wood and create a strong bond. The ca you have on now might hold the hinges to the wood but there are not enough hinges to take the stress of flight and the hing itself might fail also the elevator having such large areas of unsupported length might start to flutter and rip the elevator off. when done properly ca hinghes are great but when done wrong its a horror story waiting to happen

RE: Avistar assembly question
 

I found one extra hinge hiding behind a piece of cardboard in the box. I cut a new slit directly in the middle of the elevator and in the fuse under the rudder. Put in the hinge the right way this time, and it's much stronger.

Question about the engine. I am using an OS .46AX in this. The holes on the engine mount are further apart than the holes on the engine itself. I'm not quite sure how it's supposed to go in this way. Can anyone offer some advice? I looked all over the instructions, but there's nothing clear saying how it's done. Just says attach the engine with the supplied hardware. Attached a pic to help explain better. I can't imagine you're just supposed to sandwich the engine between the two brackets.

Thanks in advance.

RE: Avistar assembly question
 

there should be a flat metal plate that lines up to the holes in the mount and the ears on your engine sndwich between the mount and the plate. if you look at the online manual found
here http://www2.towerhobbies.com/cgi-bin...?&I=LXPY56&P=7 the second page shows
that there is an addendum to the manual for new engine mount hardware. Good luck.

RE: Avistar assembly question
 

Pete1burn.. I thought you meant 2 hinges per side, not just two hinges for all
of the elevator.. Guess it was a bit easy flexing the elevator to cut the slots out
and installing the correct way???........ So now you have a total of 3 hinges?? You
still have to question the bond of your other two hinges.. Which "most" likely
will not be as strong as it should be..... Not to mention alignment...

You should really take the extra time, get some new CA hinges from a hobby
shop and replace them all correctly... Better safe than sorry!!!..
Bringing her home in a bag would not feel great, But hurting someone or even
worse...... would be tragic

When thinking about whats said above... Know that our models are like bullets
with meat grinders on the front of them... They can be very unsafe and dangerous
to yourself and people in the area if we lose control of them...
So we have to put each model together as it should be and each kept maintained
so as to do all that we can to insure that all is up to par and ready for flight....
I'm off...... B Good...

RE: Avistar assembly question
 

For the motor mount, look at page 24 of this manual. Different plane but same basic mount concept:

http://www.horizonhobby.com/ProdInfo...450-manual.pdf

It DOES just "trap" the motor between the brackets. Works real well and allows for adjustments.

RE: Avistar assembly question
 

Thanks for the advice. Purchasing some more hinges and a slotter at my LHS this afternoon.

Yet another question on the fuel tank - this is supposed to push all the way up to the firewall so that the rubber neck with the fuel and pressure lines are through the firewall, correct? It took me a minute to see that the fuse was cut perfectly to accept the fuel tank. Just confirming before I make any more mistakes. :)

RE: Avistar assembly question
 

Yes, that is how the tank mounts in the plane. Push the tank all the way up to the firewall so that the neck of the tank sits in the hole of the firewall.

Ken

RE: Avistar assembly question
 

How are you supposed to see the fuel level without taking off the wings then? :D

RE: Avistar assembly question
 

Oh yeah, props. I bought a bunch of 11x6 wood and nylon props. If I place a wood prop on a pen, one side droops down, so it's off balance a bit. Do I just sand the heavier side a bit until it evens out? I know vibes from unbalanced props is a bad thing.

RE: Avistar assembly question
 

In all seriousness, you're not. You fill the tank before each flight so you know how much fuel you have.

RE: Avistar assembly question
 

NEVER remove material as it may weaken the blade. You can spray clear varnish on the back of the lighter blade to make it heavier. Do this in thin coats.
On composite blades you can add paint to both tips to make them easier to see when running. Add more to the lighter blade.

RE: Avistar assembly question
 

Simple, just fly until it runs out of fuel, then you'll know its empty :D:D:D Sorry, just couldn't resist that one.

You need to time a full throttle engine run on the ground and see how long it runs. Use a timer set at 1 or 2 minutes less than the amount of time it took to run out of fuel. Since you should fly at less than full throttle, you should have plenty of fuel left for a couple of balked landings.

For balancing a prop, I use the Top Flite Power Point Balancer
http://www2.towerhobbies.com/cgi-bin...p?&I=LXHY61&P=

Just make sure you use it in a draft free environment as even a small draft can cause a prop to rotate.

Hogflyer