By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by CML

David's Standard Ballerina

First scratch build for many years

All Topics | Latest Posts

Search for:  in Thread Title in  
john stones 118/01/2016 22:19:09
avatar
10793 forum posts
1481 photos

Hobby King David, good stuff strong as Profilm

John

David Hayward.18/01/2016 22:28:27
avatar
170 forum posts
82 photos
Thanks John
David Hayward.19/01/2016 21:22:07
avatar
170 forum posts
82 photos

I am using a Slec tank and so needed to make the opening in F3 slightly deeper. After fuel proofing the tank area I formed a snug fit with foam using impact adhesive to hold it in place, so the tank is removable and held securely in position by the foam.

Servo bearers also glued in position after test fitting with a servo.

20160117_162154.jpg

David Hayward.19/01/2016 21:27:07
avatar
170 forum posts
82 photos

Construction of the first wing is under way and looks pretty much like everyone else's....

20160116_123153.jpg

20160116_140241.jpg

David Hayward.24/01/2016 17:21:58
avatar
170 forum posts
82 photos

The first half of the wing has progressed enough to remove it from the board and make way for the second half.

20160124_165001.jpg

Now the bad news, on starting to build the second half I made a schoolboy error and forgot to include the 1/16 cap strip under the the rear spar adjacent to the aileron. All spars and ribs glued and then I realised my error. I lifted it off the board but was not happy that it was going to be right to just glue the cap strip on.

I thought I was going to have to cut all new ribs however before finally scrapping the wing built so far I decided to try and take it apart. I had used pva glue and so tried holding one of the joints under running water; this had the desired effect of softening the glue and enabling me to gently open the joint. It would have been a lengthy process to do this to each and every joint so I put 1/2" of water in the bath and popped the wing in to soak for about 3-5 minutes. This softened all the bottom joints which then came apart so I turned it over to soak the top to release the top spar.

Carefully dried off all the pieces with a towel and then left to dry slowly for 24 hours. While I had this interruption I built a bench for the spare bedroom as I had been using the dinning room table as the garage is too damp and plans tend to grow by a significant amount.

20160123_130940.jpg

Well it appears to have been a success, no ill effects on the wood as far as I can tell, so back to building the second part of the wing for the second time......and paying attention this time!

20160124_114024.jpg

Peter Miller24/01/2016 18:19:27
avatar
10407 forum posts
1232 photos
10 articles

Now that is dedication to making sure you got it right.!

kc24/01/2016 19:31:56
6145 forum posts
169 photos

Sometimes an error can be overcome by bodging but usually it's better and often quicker to re-do the part entirely. David may be the only person building exactly to the plan so full marks for doing it properly!

David Hayward.31/01/2016 17:42:55
avatar
170 forum posts
82 photos

So, after my minor discretion the second half of the wing is in pretty much the same state as the first and ready for the ceremonial joining of the two halves. I have followed Peter's method in as much as R1 of the first half is perpendicular to the board when built, so all the dihedral angle goes onto R1 of the second half; trust I have that right. I came up with the following method to enable me to cut the spars at the correct angle for them all to meet....

20160126_200005.jpg

A temporary template the length of the wing panel, raised by 2" to give me the angle. Any other suggestions?

So then the necessary image of the two parts clamped and drying. I used epoxy on the areas covered by the dihedral brace and pva on all other parts. Having gone to the trouble of trying to get the angle on the top spar correct and a nice close joint I ended up with about a 1/16" gap between them. While I would have preferred a closer joint I am trusting that the strength of this joint comes from the brace running along the spars and my 1/16" gap won't be an issue?

20160130_180424.jpg

Edited By David Hayward. on 31/01/2016 17:43:45

john stones 131/01/2016 18:00:43
avatar
10793 forum posts
1481 photos

Yes brace gives the strength, I get little gaps all over, fill em with glue like the rest of us wink

John

David Hayward.31/01/2016 18:29:14
avatar
170 forum posts
82 photos

Thanks John, I don't feel so bad about it now.

David Hayward.31/01/2016 18:54:34
avatar
170 forum posts
82 photos

Decided to tackle the aileron bell crank installation next never having done this type of installation before. I have made my own bell cranks from some 1/8th plastic, mounted these on ply plates as per plan, then attached piano wire linkage to servo having just bent the end 90 degrees; I will solder a washer on to secure later, but to begin with I just wanted to assemble everything dry and check operation.

It became obvious once assembled that the piano wire link should lie central top to bottom but close to the leading edge side of the hole as movement in either direction causes the piano wire to move back towards the trailing edge side; if that all makes sense? a couple of images should hopefully make this clear...

20160131_142329.jpg

20160131_142416.jpg

20160131_142555.jpg

I have initially tack glued this and when this is dry and the mountings are held in position I will finally glue and add triangle section to support.

Peter Miller31/01/2016 18:59:47
avatar
10407 forum posts
1232 photos
10 articles

That all sounds perfect.

Just like I set mine up.

And on your problem with the bgap betwen the root ribs. Now you know WHY you glue the second R-1 in while joining the wings. That way there is no gap!!

john stones 131/01/2016 19:00:40
avatar
10793 forum posts
1481 photos

Either use a nylock nut or make sure you thread lock those bolts, they're very sneaky and run off once covered surprise

John

David Hayward.31/01/2016 19:11:26
avatar
170 forum posts
82 photos

Thank you gents; its good to get your affirmation so I know I'm not too far off track. I probably didn't explain it very well Peter but I managed to follow your instructions and glue the second R1 when joining the two wing halves, but I did end up with a small gap between the ends of the top spars which you can see here20160131_190900.jpg....

Peter Miller31/01/2016 19:16:50
avatar
10407 forum posts
1232 photos
10 articles

I sometimes do the same. The dihedral brace will cover that and the sheet covering joining to the ribs will add strength.

An almost identical wing withstood 24.8G so you don'tneed to worry.

David Hayward.02/02/2016 20:03:43
avatar
170 forum posts
82 photos

A quick question about the undercarriage legs, I have belatedly realised the ply support actually goes one full rib/bay beyond the end of th u/c legs; assume this is correct and not a discrepancy on the plan?

Devcon102/02/2016 21:09:00
avatar
1394 forum posts
487 photos

Hi David,

I guess it would go beyond to help spread the load into the wing structure.

Great build, very neat and you're a braver man than I to attempt that fix on the wing.

Regards

John

Peter Miller02/02/2016 21:14:44
avatar
10407 forum posts
1232 photos
10 articles

Actually it is as per my drawing Not sure why I did it that way but it works.

David Hayward.02/02/2016 21:54:22
avatar
170 forum posts
82 photos

Thank you John, Peter, had a sudden moment of doubt and wanted to make sure as I was about to rout out the sheeting to expose the channel for the u/c wire. I'll get to it!

David Hayward.08/02/2016 13:39:41
avatar
170 forum posts
82 photos

Continuing with the aileron linkage and servo set up I had a look at how I could mount the servo within the centre section as required. I came up with the cradle type of structure here, however later discovered this was actually too deep and fouled F4 when offering the wing up to the fuselage to check; good job I checked!

20160208_131744[1].jpg

Plan B, I noticed Peter has suggested some Radio Active servo mounts so have ordered a set of these; much simpler. While I wait for these to come I carried on with the wing tips. It seems people have approached these in different ways, I have kept pretty much to plan (I believe) and this is what I have so far, top and bottom view...

20160206_174202[1].jpg

20160206_184054[1].jpg

Yet to cut and fit the edge strips around the perimeter of the tips but this will be next.

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of RCM&E? Use our magazine locator link to find your nearest stockist!

Find RCM&E! 

Latest Forum Posts
Support Our Partners
CML
Gliders Distribution
Wings & Wheels 2019
Pepe Aircraft
electricwingman 2017
Cambridge Gliding Club
Slec
Sarik
Advertise With Us
Latest "For Sale" Ads
Do you use a throttle kill switch?
Q: This refers to electric-powered models but do you use a throttle kill switch?

 Yes
 No
 Sometimes
 Rarely

Latest Reviews
Digital Back Issues

RCM&E Digital Back Issues

Contact us

Contact us