Melchizedek

Hi Jerry,

The black servo mounts were purchased from DreamWorks ->> http://www.dreamworksrc.com/catalog/Servo-Mounts-Arms
They have a couple for the different brands of servos.

A little heads up on this mount. It said it fit a standard Futaba servo. Well it kinda did.
First the inside corners of this mount have a very small radius.
My Futaba servo case is square. My square peg in there round hole kept the servo from seating far enough for servo screws to line up with threaded mount holes.

I did not find a lot of solutions for side mount servo trays to fit my application. When I did the out of stock button was lit up.
So I decided to file the round hole to fit my square peg. It didn't take much and this mount is very beefy so it didn't really weaken it .
Now that the servo seat nicely, issue 2 raised its ugly head.

The threaded servo mount holes were slightly out of line with center for servo holes.
What this meant was I could not use those little metal eyelets that come with your servo.
Those things that the mount screw bears down on and keeps your servo floating in a sea of rubber.

Well my servo still has the rubber sleeves but no metal eyelets.
My servo is swimming in a puddle of rubber instead of a sea.

It is possible I clicked buy on the wrong one or they shipped the wrong ones or ?


Another alternative is what I did on my Kadet.
I made wood rails for the servo to slide straight forward and back.
And then formed an aluminum band to clamp it in place.
It was necessary to grind the mounting ears off of servo for this.
Do you think this voided my warranty ?




Kevin

YellowBlueBird

Thanks. I was not aware of this site.

Jerry

Leroy Gardner

Kevin you have all the tricks of the trade up your sleeve and useing them on your plane suggests you have been holding out on your abilities which are showing up all over the plane. Well if you got them I say use them, it is intresting to see the many building styles we all have and learn new ingenious ways of doing things from a rookie at that, or so you say.

Plane is looking good, can hardly wait to see what you do to the fuselage.

Leroy

VincentJ

+1

Melchizedek

Thanks guys,
I can't wait to move forward to the rest of the build.
Soon very soon.

I also can't wait for VJ's paint and Leroy's maiden. Very cool things to come.

Kevin

VincentJ

Kevin I make my own servo brackets from aluminum angle stock that I purchased from the hardware store. It's easy to make, you're assured a perfect fit for the kind of servos you are using and they are very inexpensive...

Melchizedek

Vince, Very nice solution. I will use your method next time.
Thanks for sharing. One of those V8 moments if you know what I mean.

I was able to work on the plane a little this week,
Think I'm gonna try to do an hour here and there thru the week.
They start to add up and make a dif eventually.

Put the outer wing panels on the inner to check fit.
I notice when the joiners were tighten down that there was a lot of lateral play at the joint on the leading edge.
Turns out all those huge lightening holes make for a lot of flex side to side.
If I had to do it over I would have skinned the bays both sides of the joint like Leroy did on his.

First I thought of adding some torsional framing at the joint to fix the flex.
Then it dawned on me. The wing tips when glued to the other end will stiffen this up.

So I proceeded to glue the wing tips on.
This was a Pain In the _ _ _.
The FG wing tips did not fit very well. The opening was bigger than the wing tip.
I ended up cutting a slice in the trailing edge of wing tips and removing some material to be able to pull them together on the small end.
I wanted to epoxy them on but this would be impossible at least initially.
I used thin CA. Held and glued and inch or so then move on until all the way around.
First attempt wing tip was crooked and had to pull it off. Next time around I spot glued in a few spots first and then checked.

The pictures don't show it but there are some surface undulations especially on the flatter bottom side.
There will be some bondo and elbow grease to get them right.



The wing tips did stiffen the wing panel right up. No more flex.
It was kinda cool watching the wicking action of the CA .
The translucent fiberglass showed everything.
Then My sinuses said " hey butt head, it ain't that cool, just wait, i'm going to get you "
I will finger some epoxy at the inner joint line to make it strong.

Next up I straightened the other side of the wing joint with another layer of epoxy and micro balloons.




Kevin

triumphman49

My Feedback: (149)

Mel, Got one of those dumb questions for you, . . . . Using the RDS setup is a computer radio the only "throw" adjustment? ?

Thanx - T-man49 in Al

Melchizedek

T-man,

No dumb question at all.

The flipper arms if gotten form IRF machine works come in 3 different angles.
Off hand I can't think of the exact angles. But think of them as small med and large.

In my setup I am using the med one. The throw is set by the servo endpoint on the transmitter.
My end points are at about 50 % . I could have gone with small.

Also the angle of attack of the servo arm will change angle of deflection
ie my servo's are at 90 deg to flipper pocket. If you change the angle of attack for example 75 %
The overall travel of aileron lessens.

But the only way I know of to set the throws (fine tune) is by transmitter.

Hope that helps

Kevin

triumphman49

My Feedback: (149)

Thanks for that quick response Mel. Should have guessed mfg would have allowed for some form of varied throw.

I do like your choice, . . . . suspect that as your familiarization grows, the servo movements will be more "normal" !

T-man49 in Al

Melchizedek

T-man brings up a good point that I didn't ponder.

Does anybody see a dark side to only half rotation on the aileron servos ?

I do have a set of the less angled flippers. I could desolder the mediums and solder in the small angle flipper arms.
Thus giving full rotation (or near) of servo.

This would be a drag, would only want to do this if benefits warrant it.

Thanks,

Kevin

Leroy Gardner

Kevin one of the live and learn things of RC is changing some of the things on the plans. In most cases it doesn't make that much difference where control throws are concerned. On the positive side when you can do that with servo arm lengths and horns you have eliminated one more element that can go wrong. I did stick to the plan when I did mine and glad I did, the differential is dead on and there is nothing to program at the radio, can't say that at the rear where there is 3" on elevator and rudder, I can change the position on the elevator arm and solve most of it there and radio adjust the pull pull on rudder.

You made a comment on skinning your wing joint so here is some food for thought. When you cover them the covering will likely pull the ribs inward some creating that "oh crap" look that you will instantly know why. If it were me I would pull the rib caps and do one bay on outer wings in sheeting and sheet the whole center section, the reason should be obvious at this point, but thats only if it were me. Forgot to mention I would have also skinned one bay at wing tips also on a wing that size, they are always the first thing banged up, besides giving more to stick the covering to unless your going to wrap them with covering. Just some thoughts on my end, your doing great.

Leroy

Melchizedek

Leroy,

Your posts are always well thought out. Thank you.

Concerning the two bays at each wing joint. I am pondering skinning them like you suggest.
The ribs stiffened up considerably with the layer of epoxy and micro balloons. Not enough I fear that the fabric won't have the last laugh.
Will think on this.

Well I cleaned up the wing joints.



Having tightened the joiner hardware half a dozen time I started pondering what I have read a few places.
That is that the set screws on the joiners have a tendency to strip out. There is not much more than and 1/8 inch of aluminum thread.

So I decided to put some insurance in (just in case) (you never know) (Murphy came calling) (Gorilla grip strikes again)

I put two Merlyn Locks in each joint. One behind main spar and one behind secondary spar.

If you are not familiar with Merlyn Locks, go to this tutorial by the originator Merlyn Graves.
It is about midway down the page. ------>>> http://www.rcscalebuilder.com/forum/...37&PN=0&TPN=30

First I needed to backfill the wing rib with some 1/8 " aircraft ply.
Then I did just as Merlyn does.






The area that the brass tube projects thru the wing will get blocked in for support and also a surface for covering to attach to.
I used Merlyn Locks on my Something extra. This is what it looks like after covering. The two oblong holes to the right of each wheel pant.




Till next time,

Kevin

Leroy Gardner

Great idea on the Merlyn locks, you just solved the problem before you had it which you also found. I never did care for that kit joint that so many have problems with, there is alot better way to do it. I think many don't realize the forces at that joint that the large wing area creats. You did a good job adding some extra bonding of your joint track, that part looks pretty solid.

Leroy

Melchizedek

Leroy, concerning the Kit Joiner bars. I think I am going to try and add some material to one edge (set screw edge) of the male ends of the jointer hardware.
Goal being to make it a very snug fit and eliminate the set screws. Therefore relying only on the Merlyn locks to hold wing together.
Also eliminating 3 more holes in wing bottom.

I wish I had gone with wing tubes like you did. But I think I will have a tight sound wing joint in the end.

Kevin

Leroy Gardner

I guess I have spent so many years in the fabracation industry that I carry that experience into my plane building, the thing about that joint has already proven it's self to be flawed, not so much as to total failure but to the point of slop and striped out retainers and a case of what to do now. Part of the problem lies in the short coupler not spreading the forces on it over a long enough area to take the stress off of one place. The wing is a giant cantilever that produces the crow bar effect directly on the short joint, why that has never been addressed is beyond me, it's left up to the builder who in most cases assumes it must be okey because he don't know any better regurdless of how much has been said about problems with it. Far be it from me to tell anyone how they should build or do anything with their plane. but having knowledge of the dynamics of forces in structure is a good guide line for me when I build and make changes to my planes especially where the wings are concerned. It's still not too late to put a wing tube in with what is already there, personally I think down the road you'll wish you did.

Kevin there is no doubt about your building capabilities and as you grow you will find that knowledge is your best friend. Your a wood worker and if you had to put a cantilever type 4' extension on your counter top that had to support 100 lbs. on the end and could not use a kicker for support how much would you build into the joint to support the force of 100 lbs., it's the same thing, think about it.

Leroy

Melchizedek

Well a little more progress.
I blocked in the Merlin Lock tubes with balsa sticks I used 5 min epoxy on this so the tubes got bonded well to the balsa.
This will all get sanded down to the form of the wing bottom some day soon.



Next up I back tracked a little.
Due to the overwhelming response from everybody to my question concerning servo rotation (post 161)
I decided to change out the flipper arms. The first photo shows old and new flipper side by side.
2nd shows both new. With the differential of the ailerons I now have 82 % and 60 % rotation.
I feel much better now that my little servos can stretch there legs a little.



Next up will be to join the two center wing halves together and then I will start on the fuse.
I will put a field joint in the fuse just behind the wing trailing edge.
The reason for this is to fit this plane inside a Honda civic.
Also one other change I am pondering is a full cockpit with pilot.

I am really ready to move on from the wing. But feeling animated about the fuse.

Kevin

Melchizedek

Glued the two center sections of the wing together this morning.
This was a messy affair. Sig recommended slow cure epoxy.
No kidding, if you used fast set up it would be to bad for you.
I used hysol 9462. It wont be dry till late tonight but will be forever one.
If you look closely there are 2 Dihedral braces that set the dihedral and lock the 2 sections together.





There is more to do to the center section but not till this part is dry.
So I will set this aside and ponder the fuse .


Kevin

Melchizedek

Got up very early this morning to get some work done before Mothers Day festivities.

As I stated in my last post I am going to have a field joint in the fuse just behind trailing edge of wing.
If I followed the build, the fuse has a joint in it. Just it gets glued together perm. My joint will fall one bay back.
The fuse will break at F6. 1/8 aircraft ply bulk heads will be added hear both sides of joint.
These bulkheads will contain alignment dowels and Merlyn Locks.
The rudder and aileron servo will be placed just inside F6 on tail section.
I know this is adding weight to the tail (cardinal sin) but will try to keep weight to minimum.



So I needed to replace wing saddles cause they broke at the now wrong place.
Laid wing saddle parts on plan and glued a scab to tie them together at there correct location.
I then traced and cut out a couple of blanks. Then put Mr. Knees to them to finish the cut.




With the wing saddles made it was time to frame up the front section.
It was necessary to shorten the front fuse by 1 1/8 inch to accommodate my DLE 55ra.
The framing at F6 and the diagonal cross brace at F6 was epoxied in.
Also vertical stick at F6 is spruce as is all perimeter sticks.
The dark line at the saddle joint and F6 stick is 1/16 ply.
The angles of each end of saddle were a little off once corrected it needed embiggened.




If there are any Mom's following this thread ( you never know).

Happy Mothers Day

Kevin

acerc

Just for clarification, you are building the fuse so that it will be separable at the former F-6, front half, rear half, and held together by fasteners for flight? Right?

Melchizedek

Yes, that is correct Robert.

acerc

This is going to be interesting!!
You have more kahuna's than I...

Melchizedek

Oh contrar Robert. You will be flying that soon to be marvelous piece of art soon.
That sir is Kahuna's of the Grande type.



The second front fuse frame is framed up and one rear fuse frame is together.
The front fuse frame is eventually skinned on the inside with light ply. Only the first bay or so is skinned on the aft fuse.
So I decided to use epoxy on all faming joints and let the squeeze out create a fillet.

The top longeron on the rear fuse gets splice at the beginning of the stabilizer.
This is to give + 1 deg pos incidence. I decided to increase the length of the splice.



A 1/4 inch spacer is placed between front and aft fuse at the field joint.
This space will be taken up by the two 1/8 ply bulk heads to be installed later.




Kevin

VincentJ

Nice work Kevin, will you be adding gussets on your joints?

Leroy Gardner

Fore some strange reasion I knew this was'nt going to be your traditional fuse. build, almost stranger than fiction. If there is a will there is a way, is there a why?. Intresting to say the least.

Leroy