Any ideas about how to fix this?

[birdy]

Now, I have finally got around to building the wing of Mr. Miller's Harmony, I've just stuck on the top sheeting and removed the washout wedges. Then I checked, as instructed, that the washout is equal.

 

That is when I realise that I've just built negative washout into one of the wings (). Now I thought that the best way of fixing this would be to remove the top sheeting, but I seemed to have glued that on quite well, so if I do It'll mean destroying it. Any good Ideas before I try doing that? 

Edited By birdy on 24/04/2011 11:57:54

[Alan Cantwell]

erm, fix wot?

[Dave Potter]

Try again birdy. We can't fix what we can't see.

[David Gilder]

Easy to fix empty spaces...

 

Put something in it!!!!

 

 

Hee hee hee hee!!!!

 

[birdy]

Sorry, hit that enter instead of Tab

[Alan Cantwell]

come on then, gerrit SORTED,

[Bob Cotsford]

sight unseen - you have given it washin instead of washout, you could try damping the top sheet with a dilute ammonia solution and pin it down with the correct washout while it dries.

 

who knows, it might work.

I think I would probably just put it down to a lesson learned and build another wing.

Edited By Bob Cotsford on 24/04/2011 18:57:56

[Steve W-O]

Use a steamer, one of those stupid things they sell on TV saying it will clean your house.

 

They work very well on balsa, weight it past the position you want to go, and steam it top and bottom, then leave it for a few days, take the weights off, and after a few more days you will see if you need to go further.

 

I imagine a wallpaper remover would work to.

[Alan Cantwell]

EASY PEASY, i take it the wing is sheeted? make a series of cuts through the sheeting, at 45 degrees, this will take the torsional strength out of the sheeting, weight it down, prop up the wing tip trailing edge, this will close the gaps up left by the knife, glue the knife cuts with ALIPHATIC RESIN, this stuff sands, if you cannot get enough washout, then make the knife slots wider, works every time

[Biggles' Elder Brother - Moderator]

Clever idea. Though I'll try to avoid needing it

 

BEB

[birdy]

Good plan Alan. I'll try that - even if it doesn't work then the sheeting would be ruined anyway... It seems the simplest idea, but thanks anyone who suggested anything.

[Alan Cantwell]

it not my idea, it belongs elswhere, but its nice to pass on these tips, innit done it twice, works well, just watch the knife near the mainspar, and use a keen blade

[birdy]

Done that and I think its worked. Thanks again. So much easier then cutting it off...

[Alan Cantwell]

just make sure you have given the glue time to go off, and both sides are relexed up the same amount

[Peter Miller]

Sorry that I missed this when it was posted.

 

Cutting the sheet at 45 degrees was not a good idea. it weakens it too much. You could have done it by simply making several slits along the grain top and bottom and then pinning it down with the washout and running CA into the top slits. Pick it up and making sure that the washout is still in put CA in the slits in the underside.

 

How did you manage to insert the wedges from the front or did you put the thicker one in at the root.

[Erfolg]

Hmm

 

I have a model which has the wing built flat, the model is prone to tip stalling and flicking out during loops.

 

It would benefit from some washout. The wing is fully sheeted, will slitting top and bottom skins work?

 

It will save me building a new wing, or just leaving the model as a hanger queen.

[Former Member]

[This posting has been removed]

[Tom Wright 2]

Posted by Tom Sharp 2 on 26/04/2011 18:31:56:

this thread clearly shows the error of not buying ARTF

 

 

 

 

 

Och.........

 

TW2.

[Peter Miller]

Erfolg

 

Yes, you can get washout by slitting the sheet lengthwise as described.

 

This thread does NOT show the error of not buying ARTF . It shows the error of not reading the instructions properly and building as they were meant to be.

 

I have seen more ARTFs that wanted to crash or that have come to pieces in the air than I have ever seen of models built properly that showed the same tendencies.

 

Such as the Kyosho CAP 232 that had the wing with the maximum curvature on the underside. NO, not a an assmebly mistake It was designed that way and that model was notrious for spinning in. Or the Kyosho Spitfires tha regulalry lost half a tailplane...including two of the demo team that lost them at Sandown.

 

Then there was the manufatcurer that bproduced a range of semi scale models that were all lethal to fly. I saw three of them and they all spun in. Some twice after rebuilding. On this very forum someone asked Is there &&&&&&&&& model that actually flies.

 

I believe that they have improved since then.

 

I will make no comment on the original remark...I think it is obvious.

[Alan Cantwell]

Posted by Peter Miller on 26/04/2011 18:15:37:

Sorry that I missed this when it was posted.

 

Cutting the sheet at 45 degrees was not a good idea. it weakens it too much. You could have done it by simply making several slits along the grain top and bottom and then pinning it down with the washout and running CA into the top slits. Pick it up and making sure that the washout is still in put CA in the slits in the underside.

 

How did you manage to insert the wedges from the front or did you put the thicker one in at the root.

there is an 88 " span mustang with a 3w 60cc fitted, which will certainly disagree with you, it works, and works well the glue is stronger than the wood, the angled cut spreads the load down the wing, one cut overlaps another, therefore, the glue strengthens the next slit, using cyno is a bad thing on any sheeting join, it does not sand, the glue i mentioned sands readliy, we have only cut the top sheeting, thinking about it, would cutting the sheet the opposite angle on the bottom help the process, or hinder it? would both slits close up? if both sides where cut the same way, would the bottom ones open up??? our wing, i might add, felt superbly strong, its covered in profilm,

[PatMc]

I've rectified wash-in the more or less as Peter described on a built up all sheeted Seychelle glider wing & on a couple of badly made foam veneered wings. Only difference was that I did it with a single grain-wise slit root to tip & used PVA or epoxy.

On a couple of the models the wings were already Solarfilmed so a span wise thin strip of the existing film was removed & a wider strip of contrasting coloured film hid the repair with a matching strip applied to the other wing.

[Alan Cantwell]

sorry, i cannot see how you can tip the tip up by using a span wide cut, suerly all that can do is benda the back end up a tad--the enitre back end, several 45degree slits will let the wing twist from the tip, to the root, the models we where sorting where a lot bigger than the seychelle though

[Peter Miller]

I only descibe fixes that I have used myself and that I know work.

 

As I see it, cutting the sheet at 45 degrees cuts across the grain thus weakening the sheeting. slitting down the length does not weaken the wing.

[Peter Miller]

The reason that the wing is stiff is that the leading edge is a sealed D box. slitting the sheet down the grain allows it to slide and twist. The glue then seals the D box again and stops it sliding back to its original position.

 

Now you can tell me that you don't see how it does. OK. All I can say is. IT DOES work, It worked for me on a badly warped wing that had wash in after major repairs.

[Alan Cantwell]

fair enough peter, but the engineering in the fix reinforces every overlapping slit, i also know it works, and works well, vary the amount of slits for how much washout is needed, we didnt slit every inch, on the stang wing, it was every 8 inches on an 88"wing, on a, say, 60 inch wing, i would suggest every 4-5inch