Hi,
I've got a slightly slanted hinge slot on the mini showtime... it's on the wing. The trailing edge is very thin, so the hinge slot portions of the trailing edge have an extra piece of balsa as thickener... so it's not viable to cut a new hinge slot adjacent to the old one.

So any special tricks for fixing a slanted hinge slot without ruining the tightness of the slot?

Thanks

What do you mean by "slanted?" Anyway, as long as the opening of the hinge slot is centered in the TE of the wing and the LE of the aileron I don't think it matters if the slot is "slanted." (I assume, by slanted you mean the slot angles upward or downward if viewed from a cross-section.)

Or, as long as the aileron aligns with the wing, you'll be fine (providing there is enough "meat" around the hinge to hold it securely).

I mean that, if you were to try to trace a straight line through the hinge slots, the "slanted" one would not be parallel along that traced line (it would instead intersect it at an angle). That's on the wing... on the aileron the slots are all straight. In other words, if I were to force the aileron installation without fixing the slot, on one of the CA hinges, there would be a significant twist causing the aileron as a whole to not move very freely at all. The servo will have to struggle with it much more.

edit: I just remembered that Great Planes brand CA hinges are a lot thicker than Hangar 9 hinges. I think I might have some GP brand hinges around here somewhere. So if I end up loosening the slot in fixing it, maybe the GP brand hinge will still fit tightly. Anyway, if you know how the related wing structure on the mini showtime is (descibed in 1st post), you'll see why you can't just cut a new adjacent slot.

I get what you mean - slanted when viewed from behind. Just cut a straight slot in the SAME place - it will all hold together ok once you add the CA to the hinge (assume using CA fuzzy hinges).

Cam

Yeah I guess the balsa wood might still be able to expand out (if the repair cutting is done just enough and no slivers of balsa come out in the process). Hangar 9 CA hinges are not as "fuzzy" as Great Planes hinges for example... they are a lot smoother, thinner... sort of like compressed.

That could work... just have to be done very carefully... can't let the old slot line influence the blade tracking of the hobby knife as I go. Have to be very careful not to allow slivers to come loose as I remove the blade tip. It will get a bit "mushy" I guess.

Just get the hinge pushed in, then pack out any gaps with wedges sliced from balsa - just jam them in whichever side needed to keep the hinge "level". Once all straight, carefully trim off any stray bits with a sharp hobby knife, then Zap it.

For the record, I hate CA hinges and only used pinned ones or hinge points. I build bigger stuff though - I'm sure the CA ones are ok at this size.

Good luck,

Cam

So I got done straightening the hinge slot. It's a looser fit now with the Hangar 9 CA hinge, but there is clearly still contact with both sides of the hinge... it doesn't just fall out in other words... only that the wood isn't squeazing it as much as before. Suppose I could let it settle a bit for a while in case the balsa "fluffs out" again somewhat.

This particular slot is on the side of the widest part of the aileron... but that is also next to the fuse... I guess the force felt during flight by each hinge should be roughly equal anyway.

Anyway, not much else you can do I guess.

I won't be doing anything extreme with the plane... just basic lazy aerobatics, patterns, so I guess it's no biggy if that one hinge isn't perfect.

I'll still look around for those thicker GP CA hinges. If I use those will have to recut the apposing aileron slot as well, because they really are a fair bit thicker (and more "fuzzy" ) than the Hangar 9 ones.

Thanks for the help

I guess what I did was in essence very similar, but without the hinge inside at the same time. Seems to be OK. I'll pay special attention to it as I CA it. But I'll let the wood settle a bit first.

They are a wierd invention. Just wish they would give the same attention to cutting hinge slots as they do to the rest of the construction on the ARF's. It's otherwise a very nicely done ARF.

Cheers

Ohhhh, I see what you mean.

Sounds like you've already received lots of advice. I guess I'd do what some of the other guys said - just go ahead and "straighten out" the slots by cutting new ones right over the slanted ones. I don't really know what the mini showtime is, but if it's a small electric model I bet you'd be just fine even if the hinges go into the new slots a little loosely. The thin CA will wick right in there and hold them just fine (I'd use a little extra though).

Too late now I guess, but I bet Horizon would have replaced the wing for you (I'm not speaking for them, that's just my speculation).

You will find that the majority of ARFs have slots like that.

I have a number of ARFs that have more than a couple of years flying on them. All of them do not see weekly use, but a couple do. And all of them had angled slots like your description.

I fix angled slots with a razor blade. I make a straight cut and slip the CA hinge into the straight cut. It displaces the wedge. The razor cut doesn't compress much balsa and the hinge usually fits as tightly as before. When the CA is applied, it wicks into all the slots and glues them solid. I'm sure of that, as I've had the "opportunity" to autopsy crashed models that had corrected hinge slots that were done with this method.

When drops of CA are applied they wick into any slots they touch and glue them perfectly. The technique only requires that you insure there are sufficient drops, and that's no different from good slots to bad slots.

It works for me.

BTW, on the infrequent occassion that the slot is too loose, which can happen with ARFs that have perfectly straight hinge slots, I usually retrofit the CA hinge. Dubro hinges glued with Hinge Glue work great. Matter of fact, they're as easy to install as CA hinges and are bullet proof. They're also easy to use on the same hinge line with CA hinges. And I often use them as the hinge closest to the surface's control horn, as I trust them far more than I do CA hinges. And I don't distrust CA hinges when they are obviously of decent quality.

Thanks for all the inputs. Because of the way the trailing edge of the wing and leading edge of the aileron are constructed there is a low tolerance for mistakes, so the feedback on what to do and how it will turn out was really helpful. I got done hinging the ailerons today and was able to focus on doing it without second guessing whether I should be doing it another way, etc.

It looks and feels like they are holding secure and they are both moving very well so the servos will not be loaded too much.

Thanks again