Ok, I've built a couple of planes now (Nutball, Flyer, Delta, Baby Blender v2, Axon) and have two more I'm just finishing up (Old Fogey and Bloody Wonder) and I keep having the same problem on all of them.
Namely my control surfaces don't deflect well. By deflect I mean move towards the side with the bevel. They move towards the paper side just fine. But none of them move well towards the bevel.
I'm cutting my bevels with a knife. I do a score just through the paper about 5mm away from the hinge line and peel the paper off to help guide me. Then use a fresh blade to slice as close as I can to the hinge and the paper. I then go back with a sanding sponge and make a few passes to even it all up. The result usually looks great...and seems to move really well.
But then I do one of two things. On the Nutball and Axon I put tape over the hinge - it still seemed to move well by hand. But when I hook up my servos my control rods end up bending and I get very little deflection. I've checked that the holes in my horns are directly over the hinge line (I've used cut up gift cards, zip ties, grayson hobby laser cut horns and now the FT laser cut horns for my horns) and it all looks good, and I can't feel any binding...but the servos just don't want to push.
Instead of tape I've been trying Chad's hot glue trick that's been mentioned in the show a few times - just running a thin bead of hot glue right down the hinge line and then scraping it into the foam and removing any excess. But after doing this my surfaces don't feel nearly as free - and my hot glue seems to stay sticky for a few days which leaves me worried about the surfaces sticking if I move them to full extension.
I'm using .032" music wire from my LHS for my control rods. The Flyer has the best control surfaces I've made yet - but only because I used a BUNCH of zip ties to constrain the control rods:
And even then the rods tend to flex more than I'd like.
On the delta I figured they were short enough rods it wouldn't be an issue...but I think I'm going to have to add some zip ties on there as well because they're bending and I'm getting more travel in one direction than the other as a result.
The baby blender I used linkage stoppers finally instead of z bends and the triangular bend for adjustment - but again my elevator barely moves down (it always seems worst on my elevators for some reason.)
Last night I added servos to the BW and used the next size up on wire for the elevator (.047") and it seems great. no zip tie supports required at all. But that wire seems MUCH heavier and bulkier. On the ailerons I used the same .032" wire I've been using - and I get basically no downward deflection at all, the wire just bends. I'm debating whether to switch to the heavier wire on the ailerons as well or if I should just add some zip ties and see if that helps.
Maybe I'm not making a big enough bevel? I'd try with no glue and no tape...but I'm really worried about how well that would hold up since I do nick the paper while cutting the bevel sometimes.
I'm having a blast building and flying...but it's getting really frustrating having the same problem over and over - and it's always worst on the elevator it seems.
Any ideas?
Namely my control surfaces don't deflect well. By deflect I mean move towards the side with the bevel. They move towards the paper side just fine. But none of them move well towards the bevel.
I'm cutting my bevels with a knife. I do a score just through the paper about 5mm away from the hinge line and peel the paper off to help guide me. Then use a fresh blade to slice as close as I can to the hinge and the paper. I then go back with a sanding sponge and make a few passes to even it all up. The result usually looks great...and seems to move really well.
But then I do one of two things. On the Nutball and Axon I put tape over the hinge - it still seemed to move well by hand. But when I hook up my servos my control rods end up bending and I get very little deflection. I've checked that the holes in my horns are directly over the hinge line (I've used cut up gift cards, zip ties, grayson hobby laser cut horns and now the FT laser cut horns for my horns) and it all looks good, and I can't feel any binding...but the servos just don't want to push.
Instead of tape I've been trying Chad's hot glue trick that's been mentioned in the show a few times - just running a thin bead of hot glue right down the hinge line and then scraping it into the foam and removing any excess. But after doing this my surfaces don't feel nearly as free - and my hot glue seems to stay sticky for a few days which leaves me worried about the surfaces sticking if I move them to full extension.
I'm using .032" music wire from my LHS for my control rods. The Flyer has the best control surfaces I've made yet - but only because I used a BUNCH of zip ties to constrain the control rods:
And even then the rods tend to flex more than I'd like.
On the delta I figured they were short enough rods it wouldn't be an issue...but I think I'm going to have to add some zip ties on there as well because they're bending and I'm getting more travel in one direction than the other as a result.
The baby blender I used linkage stoppers finally instead of z bends and the triangular bend for adjustment - but again my elevator barely moves down (it always seems worst on my elevators for some reason.)
Last night I added servos to the BW and used the next size up on wire for the elevator (.047") and it seems great. no zip tie supports required at all. But that wire seems MUCH heavier and bulkier. On the ailerons I used the same .032" wire I've been using - and I get basically no downward deflection at all, the wire just bends. I'm debating whether to switch to the heavier wire on the ailerons as well or if I should just add some zip ties and see if that helps.
Maybe I'm not making a big enough bevel? I'd try with no glue and no tape...but I'm really worried about how well that would hold up since I do nick the paper while cutting the bevel sometimes.
I'm having a blast building and flying...but it's getting really frustrating having the same problem over and over - and it's always worst on the elevator it seems.
Any ideas?
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