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In this episode of RC Plane Lab, Ron and Tom talk all about Hinges!
Episode 59 Transcript
This transcript has been lightly edited for readability. Timestamps are retained.
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[0:00] Hello everyone and welcome to RC Plane Lab. I'm Ron. And I'm Tom. Today we are talking about hinges. Yep. It's exciting. It is exciting. Before we get into that though, I want to remind everybody we are on Patreon. If you like what we do or if you've learned anything or if you just want to support us, head on over to patreon.com slash rcplanelab and sign up we appreciate any any support we get yeah yeah
[0:27] every every little bit helps because this is really not as cheap as we imagined it was going to be when we started so well we want to do things right right so anything that we get through patreon does not go into our pockets it goes into the show it goes into buying more equipment better lighting cameras cameras yeah we've got a few of those. And just like I said, in general, to better what we give to you guys. None of it gets
[0:53] spent on airplanes or anything fun for us. No. We're still out of pocket on a lot of the stuff we do, which is okay. Yeah. But anyway, so yeah, if you want to be a Patreon, go sign up. We would appreciate it. Also, we're on YouTube. If you're not watching us on YouTube, don't forget to go check out our channel there. Which is really exciting. We're getting there. Yeah. I feel like we're getting a little bit better as we go along, but we still have a long way to go.
[1:17] It was just like a podcast. We were terrible at the beginning. I can say terrible because I felt like we were terrible. But I feel like we're okay. We shoot for okay, right? Yeah, we strive for nothing but okay. Yeah, but we'll get there. We'll get there. Like I said, it's a learning experience. There's a lot that goes into this. Yeah. Which surprised me. I didn't realize that when we started. Yeah. Like YouTube, I just thought it'd be simple.
[1:38] you throw a video up there, but it's not. Wow. Yeah, it's way over my head. Like Ron does all the editing here and the amount of time he spends on it. Yeah, I thought it was just simple. You record it with a camera and put it up there for people to watch. But it's just not quite that simple. Well, I guess on the basic area it is. But yeah, we want to do things right. We do. Or at least try to and learn from our mistakes.
[2:02] Hey, and speaking of doing things, a lot of the content that we come up with actually comes from you guys. So either through the listener surveys or by contacting us, and there's many ways you guys can get ahold of us. There are. Yeah. But yeah, you can get us- I was going to say, are you going to tell them or are you just- Yeah, I was just going to tell them. You can get ahold of us on our website, rcplanelab.com. You can text or give us voicemail at the 1-800 number. It's 818-351-9846.
[2:36] That's not a 1-800 number. It's an 818 number. But yeah, you can text that number. You can also call it and leave a voicemail. You can comment on any of our Facebook posts. Also on our YouTube videos, you can comment on those. And that'd be one other way you could get ahold of us. You can email us. I'm Tom at rcplanelab.com. And that's Ron at rcplanelab.com. Yep. There's Instagram, which I'll be honest, I really don't know how that works. I don't even
[3:06] have, I don't think, an Instagram account, but we do have a RC Plane Lab Instagram account and it is monitored by… I think both of our wives actually kind of do it. Lori probably more so than Crystal, but yeah, I think they both have access to it. So other than that, I don't know Instagram. So there's lots and lots of ways you can get a hold of us. And don't forget, we also have really cool forums out there that I am guilty of not visiting as often as I should.
[3:33] But, yeah, we have forums there, and you can get a hold of us there, too. Yeah, forums.rcplanelab.com. Yep. Ask your questions. Pretty much links to all those cool features right on our website. So the website kind of being the main hub, you can go to any of these other features just by clicking links that Ron has put on the website. Except I don't have Instagram or Facebook on there. So he's correct with most of them,
[3:57] but not all of them. That's okay. Well, that's what I strive for. Mostly correct. See, we go for okay. So let's get on the hinges. You want to talk about hinges? Yeah, hinges. Hinges are kind of exciting. Well, they are. I think they're like one of the most important components on an airplane that we install ourselves on an airplane. Well, without them, I mean, you couldn't move. No, not really. You wouldn't be able to control your airplane.
[4:20] You would just go straight into a lawn dart into the ground. That's right. And pretty soon you'll get to see all of the hinges that we're getting ready to talk about, these hinges in action and how the steps I take to install them on YouTube pretty soon. If Ronald quit being lazy and gets his editing on. Yeah, so we've recorded the episode or the videos, I guess. Yeah, the hard part's done right no no no no no for you maybe but yeah we recorded how to install a bunch of these
[4:51] different hinges i don't even know how many he did but there were quite a few and he did an okay job so we'll okay see strive for okay well we'll get to see him as soon as i get off my lazy bum and get it edited and up. Maybe by the time this is up, we'll have some done, but I'm not promising that. Yeah. Well, even if the hinging video isn't up, it'll be up shortly after, hopefully. Yeah. So at least that's the goal.
[5:17] And the easiest way to find out when it is up is go to YouTube, look for us, subscribe, and hit the notification bell. YouTube, look for us, subscribe, and hit the notification bell. And if you subscribe to our YouTube channel, anytime we post something new on there, you'll get a notification when it gets posted, so you won't miss a thing if you subscribe. Right away. Yep. So hinges. Hinges. Alright. Lots of different styles out there. Well, let's name them off. What do we have first?
[5:40] Well, gosh, I mean, before we even started naming them off, I did a kind of a, when we decided we were going to do hinges, I just rapidly kind of went through and wrote down all the hinges that I'm familiar with and the ones I use the most. And then we did a Google search and found that many more. So there's lots and lots of different styles of hinges out there. And we'll start with the most basic, which is tape. Tape? Yeah, yeah, tape.
[6:04] I don't really consider tape a hinge, but I guess you're right. When applied as a hinge, it becomes a hinge, right? So packing tape on some of our foamies becomes a hinge. Oh, I forgot. I have used that before. So pretty simple to use. You just basically cut a bevel on the leading edge of the control surface, and then you basically tape the flat side of it to the control surface to the airframe. There you go.
[6:37] You put a piece of tape across there, and now, presto, change-o, you've got a hinge. And if you want to make it extra secure, you flip it over on itself 180 degrees and then put another piece of tape on the back. Put another piece of tape. Pretty common practice with foamies and really, really small airplane. You can accomplish the same sort of outcome with monocoat or ultracote if you prefer. The same procedure, but instead of being self-adhesive
[7:05] you just iron it on not on foam i was gonna say yeah let's probably yeah we're getting back to bolsa on this one yeah yeah so if you're if you've got a really small balsa airplane you can get a cheap easy hinge by monocoating your hinge line yeah but like for the the cheap like profile throwaway type foamy airplanes that you don't want to spend a lot of money on those anyway. Right. And that's the perfect type of hinge is just packing tape. That's right. Yeah.
[7:31] I've even seen folks use, and I've used it myself, I think it's called, Band-Aid makes it. It's made for bandages. And it's a self-adhesive tape that has like a fi like a almost like a fabric embedded in it i've used that before as well the problem with that is it doesn't last very long but it's it's great for prototyping like if you're gonna design a foamy or something you just want something quick to put it together to see if it's gonna fly this tape you get from band-aid is
[8:00] pretty slick in the way it gets used well Well, really, though, I mean, like, profile foamies and stuff aren't really meant to last forever anyway. Well, that's true. I mean, like, I don't think they have a shelf life like a Balsa-type airplane would have. I mean, do you agree with that? No, I would agree with that. Okay. So, once again, that kind of goes back to the use the right hinge for the right airplane.
[8:25] And a cheap roll of tape is a lot easier to use than anything else for a profile foamy like that. True story. I wouldn't lie. And you're not a liar. That's for sure. Thanks. So the next type of hinge is probably the most popular type of hinge, and that's the CA hinge. That's the CA hinge. And all that is really, it's a very thin, flat layer of plastic that has some sort of cotton type flocking sandwiched on either side of the plastic.
[8:55] The purpose of the flocking is to wick the CA into the joint once you've prepared a joint. So really common on ARVs. Even back when kits were really popular, they were common and a common inclusion in the kit as part of the hardware package. Really super easy to use. They've provided, they're installed correctly. They're fairly durable. They're fairly strong when used in the right application. And like I said, they're fairly easy.
[9:32] You just cut a slot, slide the hinge in there on both surfaces, slide the control surfaces together, and put a few drops of CA in there, and there you go. You've got a hinge surface. So with this hinge versus any other type of hinge, how do how many hinges to put in a surface? Well, usually, so if you're not designing something yourself, if you're going off of plans, the plans will usually tell you how many hinges to use.
[10:00] I try not to get more than six inches, six to eight inches between hinges. Now, if it's a highly aerobatic with really huge control surfaces, I'll err on the side of caution and I'll go more than that every four inches or so. But really, it's kind of down to what the structure will allow you to use. kind of down to what the structure will allow you to use. CA hinges, because you have to actually create a pocket for them,
[10:37] if there's a structure on the backside of your hinge pocket that's, say, some hard balsa or even maybe plywood, then that'll kind of limit where you get to put your hinges because it's hard to cut a slot on a piece of plywood. Yeah. Well, it depends. Well, true. It depends on your tools. If you have the right tools, which we'll cover when Ron does the editing, when we do the hinge video. Well, we can talk about it here later in this episode, too. True.
[10:56] That way we can just kind of do a quick what is what and how do you use them. True. But, yeah, the CA hinge, very basic, very easy to use, pretty handy. Like if you have an airplane that is older and you want to recover it, these hinges are easy to cut apart. You just basically slice down the center of the hinge and then add new hinges either side of the old one, and off you go. Makes it easy for recovering and things like that. So pretty common hinge, pretty popular. I use them.
[11:25] It's not my favorite, but we'll get to my favorite here. Yeah, well, these are what I use on my dualist. And I know you didn't. You use something different on yours. Right. So the problem I came across, and I think this would happen on any plane I build until I kind of get used to it. So I try to the the control surfaces move farther than they needed to and by doing that i created a gap and i think that's kind of
[11:53] where that flutter came in that i had with the with the duelist could be so really i mean like i think i was going for like 45 degree deflection on that, which that plane doesn't need. Absolutely does not need that much. At all. Because when I flew it, I don't think I ever went full deflection. And I think you had the rates turned down some, too. Yeah, I think so. I don't know what it was that happened.
[12:15] I don't think I ever went full stick in either direction, and that thing had plenty of authority. Yeah, so by doing that, though, it really opened up that gap. And you have to be careful with the gap because, obviously, the bigger the more air you have going through it and that'll induce flutter yep but the trick that i found for installing these that makes it kind of easier i guess
[12:35] so you don't lose where the center is as i use a couple push pins oh yeah that go and you put the you push the push pins you push the push, hold on. That's hard to say. Yeah, you actually push the push pins. It sounded wrong when I said it. You push the push pins right through the center of that. It still sounds wrong. Sorry. Okay, for the eighth time, you push the push pins through the center of the hinge so that you mark horizontally where the center is.
[13:03] So that way when you push it into one side, it doesn't go too far. Yeah, it doesn't go past halfway. Yeah, and if this doesn't make too much sense, you can watch Tom do it when he actually does the video whenever I get that edited and posted. When you actually edit it and get it posted. But that's important because then you don't have to worry about it going in one side too far
[13:21] because you really want it to be right centered on there so you get enough bite on each side. Exactly. Yeah. Because there's no demarcation on a CA hinge, at least most of the ones, all the ones that I've seen that tells you exactly where the center of that hinge is. So it would be very easy to stick it in one side too far and not have enough sticking out the other side. And you don't even know that. Like when you're pushing it in, you could think that
[13:43] you're doing it to where it's centered. Exactly. You don't know without having those pushpins in there to kind of keep it centered. Yep. And then before you glue it, pull the pushpins out and push it the rest of the way together. Yep. push the aileron all the way to the wing or whatever surface you're doing and then bend it a little bit. Yeah. Not the 45 degrees I did.
[14:09] And then put some glue in it. And the reason I think yours opened up a gap is because when you flexed, let's say, the aileron in this case, you may have gone past the bevel that you created on the leading edge of the aileron. Yeah, I did.
[14:24] As long as the bevel on your control surface is at the angle that you want your total deflection to go, as long as you don't flex it past that point,'re not going to pull the hinge out yeah i flex beyond that point and pull the hinge out and now i have oh yeah now i have a nice gap how much glue do you put in that though so three to four drops of thin ca on either side of the hinge so i use way too much
[14:43] it's easy to do though because you want to, because you want to make sure that it holds. So after I saw it wick into both sides, I was like, well, that's good. Let's flip it over and do it again. Do it again. I was like, well, that's good. Let's flip it over and do it again. Oh, it's dripping out everywhere. Let's put some more in to make sure it got in. Yeah, thin CA is like our last episode we talked about glues, is like water. And that stuff will run everywhere so
[15:06] really three to four drops per side is plenty and i noticed too when i was doing mine with the ca i don't know if it was out gassing or whatever it was but it changed the the covering a different color yeah left kind of a white fog or a white haze like a haze on it and it's hard to get off it is it comes off yeah debonder will get that off. Yeah. Which you don't want a lot of debonder around your hinges that you just glued.
[15:29] No, but a little bit on a paper towel, usually that'll wipe right off. But yeah, it'll definitely leave a haze, which we talked about in the glue episode. Yeah, I think I used trim solvent to clear mine up. It worked well, but it actually discolored part of the covering, I noticed. The trim solvent did? It did. Oh, wow. Yeah, so I don't use that anymore on places where I'm gonna see. Yeah, that's strange because usually trim solvent, well, at least with monocoat, that's who makes it.
[15:56] Or made it, I should say. I didn't use monocoat. Oh, that's right. I used that China Coat stuff, or whatever it was called from- Interesting, that's good to know. Yeah. Because I did not know that before you just said that. Well, it was just the blue was the only one I saw it on. I use a metallic blue, and that's where I saw the difference in color. Oh, be darned. It kind of just took some of its finish off. Oh, be darned. Yeah. Okay. Be careful. All right.
[16:18] So be careful if you're using Monaco trim solvent on anything but Monaco. That's a small area first. Small area first. So the next hinge, pretty much identical in construction to a CA hinge minus the flocking, right? Get the flock out of here. I knew that was coming. I was waiting for it too. Yeah, I know you are. Is pretty much the nylon flex hinge. This was standard equipment before CA hinges were popular. So CA hinges
[16:47] pretty much replaced these in kits and ARFs. But basically, it's just a flat piece of nylon with a, I don't want to say a void, but a molded in kind of a part line right down the center of the hinge. So you have an A half and a B half half and exactly how far to slide it into the slot to get to halfway so you don't have to use the push pins if you don't want to and so it's just kind of like a thinner piece like a thinner spot in the middle
[17:15] to let exactly how far to go yep and that actually is where it bends too then right exactly that's designed to be yep that's designed to be flexed at that point. Also, usually, oh, go ahead. I was going to say really quick before you go on. So, time frame on all these. Like, are CA hinges the newest type of hinge? Or do they just gain popularity? Well, so the CA hinges are probably the newest style of hinge on the market that you can buy in a package.
[17:46] style of hinge on the market, that you can buy in a package. Like I'm not like in some of our bigger, like 3d type airplanes, those hinges are kind of built into the airframe, with a one piece, pen, like we're going to talk about here in a few minutes. but, but yeah, the CA hinge is probably the newest and by newest, I mean, gosh, these things, I think they came out in the early 90s. Like SIG was,
[18:05] I think, the first one on the market, and it was called Easy Hinge because they're so easy to use. And they started producing them in their kits and also as packages that you could buy. And this was early 90s. So they've been around a long time, and there apparently has not been a lot of development in hinge technology lately. Well, maybe it's as good as we're going to get then, and there's not much been a lot of development in hinge technology lately well maybe
[18:26] it's as good as we're going to get then and there's there's not much else that's simpler and easier they work really really well they really do and so do you have a problem like obviously hinges are made to flex over and over and over again yeah but i know like with plastic especially if you bend it back and forth you get the the stress cracks and then they're prone to failure over time. Does the nylon hinge have anything to do with that?
[18:50] I mean, do you have to worry about that or with the CA hinges either? They definitely have a lifespan. Okay. But because of the material they're made of, they're pretty resilient. And like the nylon flex hinge is designed for that purpose. And the material that they make it out of is designed to be flexed hundreds of thousands of times before it becomes brittle or breaks along that line. But they do have a lifespan.
[19:16] And that's another benefit to the nylon flex hinge and also the CA hinge is that they are easy to slice in half, pull your control surface away from your airframe for recovering or replacement. And then you can cut a new slot right next to the old hinge in most cases. So, but I mean, I can honestly say I've only ever seen a few times where a nylon flex hinge or a CA hinge has failed because of being flexed too much. Now, I've seen them fail
[19:47] many times, in crashes with impact damage. I've seen them separate, but as far as an operation goes, it's rare that I've seen one actually break due to, fatigue from use. Just from being used over and over again. That's good to know. So there's no, like, none of these are ones you should stay away from. They're all tried and true absolutely yeah like all the methods that we're going to talk
[20:08] about have been yeah exactly they've been tried and proven to be durable over many many years one more thing i want to say about the nylon flex hinge is that because it doesn't have the flocking on it like the cotton the cotton layers to wick the ca you really shouldn't use these with ca like the nylon hinge really needs to be used with epoxy yeah i wonder why they don't do that and they mold those hinges with like holes in the flats to allow the epoxy to sort
[20:39] of penetrate through the hinge and it creates sort of a pillar between like if you can imagine a cross section of the hinge the the adhesive would would form a pillar through that void and the hinge between the the two faces of balsa that are in either side of it to really give that a strong bond so you're not going to pull it out of the control surface if it's installed correctly but has to be done with epoxy CA I've seen folks use CA with these types of hinges.
[21:08] They'll use medium CA and then try to slide the – they'll put the CA on the hinge and then slide the hinge in the pocket real fast. That's not an ideal way to do it. Just give yourself time, use epoxy, and it's just super, super strong. You'll have a very hard time pulling that apart when it's when it's glued correctly okay so so that's the nylon flex hinge what else do we have tom so next we have the same type of hinge it's a nylon hinge but these this one it's a nylon pinned hinge
[21:38] dubrow makes these carl goldberg used to make them. Lots of companies make them. Pretty solid hinge. But the main difference is the fact that this hinge, instead of relying on that flexible piece of plastic doing the flexing, you actually have alternating joints that come to kind of key together and then are pinned together with actually a pin, a metal pin. So is that kind of like, if you looked at it, it would be more actually a pin, a metal pin.
[22:08] So is that kind of like, if you looked at it, it would be more of like a door hinge type? Exactly. Where you have an A and a B side that kind of go together? Exactly. Yeah. Like if you look at a hinge on one of your doors in your home, you open up that hinge, you can see that there's interlocking teeth that they sort of key together and then a pin slides down the middle, this is the exact same principle. So is there, because to me
[22:28] now you're getting to be a little bit more, I don't want to say engineered, but a little bit more complicated. Do you have any issues with that failing or a pin, because there's not going to be as much plastic on the pin side now, or on the hinge side, because you have obviously an A side and a B side where there's not going to be as much plastic on the pin side now, or on the hinge side, because you have, obviously, an A side and a B side where there's not a solid line of plastic.
[22:49] Do you have any more failures with this, or what's the… No, the… Like, I can just see more problems with this type of hinge than with the regular one.
[23:06] because there's a pin now in the center of the hinge, on either end of the A or the B side, because they have to make that bulk enough to house a pin, there actually ends up being more plastic, more material, more hinge at that center than there is on a flat nylon hinge. So they're actually, if anything, they're more robust than a flat nylon style hinge. And you have the benefit of having that nice, smooth interlocking joint rotating on a pin,
[23:32] as opposed to the resistance of bending plastic back and forth. Okay. If that makes sense. No, I get that then. So if you're getting thicker, so obviously then the middle is going to get thicker then, like with the hinges. So do you have to take into consideration, you're shaking your head yes. The hinge pocket. You have to take into consideration cutting a little bit more out there for the hinge to
[23:53] actually sit in? Exactly. Okay. Yeah. So you'll have to provide a relief on either the trailing edge of your airframe or the leading edge of your control surface, you'll have to provide a little bit of a relief for that pin to sit. Otherwise, you slide the hint, like if it was just sliding into a 90-degree surface with no relief, that pin would actually sit outside the center line of your
[24:18] control surface. So you do have to, and that's easy enough to do usually with a with a a custom-made sanding tool that we talked about in the previous episode or even just an exacto you carve out a little relief and we're talking a very very small it's like a v-groove then or something yeah exactly out of each side just some place where that that hinge can can be recessed so that you can maintain your hinge pin on the center line these hinges are a
[24:46] little bit more difficult to install than the standard old flat style ca or nylon hinge they require a thicker pocket because the hinge itself is is much more substantial the the plastic is actually thicker so it usually can't just the Also, the actual hinge itself that goes on the airplane is thicker than the other kinds? Yeah, usually than a comparable size flat nylon hinge. Yeah, the hinge is much more substantial. So usually… Here I go scratching myself again while I'm talking.
[25:18] That's okay. So usually when you install a pinned nylon hinge, it'll require that 60-size arrow broach that we'll be talking about in the video. But it requires material to be removed instead of just a slot or fibers separated in the airframe or control surface. You have to provide room for the hinge, and then you also have to protect the hinge pin itself, that interaction between A and B, from the glue that you're going to use to glue it.
[25:51] You don't want glue to get in that joint and lock up the hinge. Because then it's not a hinge. Exactly. Lots of ways to do that. You can use 3-in-1 oil, very carefully applied. You can use my personal favorite, which is a little Vaseline or KY, or not KY. Petroleum. Petroleum jelly, thank you. Well, jelly, KY comes in. Anyway, a little protection on that hinge pin to keep the epoxy that you have to use
[26:20] with this hinge, just like the nylon flat hinge, to keep that pin protected from the adhesive so you don't lock it up with epoxy. So yeah, it takes a little bit more to install, and they're not quite as forgiving for being out of alignment either, because all of these hinges rotate on the same center line. If that hinge is, if one hinge is installed out of alignment,
[26:42] it creates a lot of binding. So again, like we'll talk about in our hinging how-to video, all those hinges have to be aligned, which means your pockets have to be slightly oversized to give those hinges room to sort of align when you flex that control surface when you glue it up. So when you do that then, because you said to cut a slot, like a recess slot, just in one side. So do you line it up on the side that you don't have a
[27:09] recess slot cut into? No, the recess, you'll have to provide a relief on both surfaces. On both surfaces? Yeah. Okay. Yeah. Because I can see how that'd be more difficult to get it lined up. Yeah. Yeah. Because you want that, you want that, that center line where the pin is, you want that to rest equally centered center pretty much so you'll have to have a relief on both sides because the hinge is mirror image one
[27:30] side to the other but that should be okay because when you like when you put the hinges in to get them lined up it's it's an epoxy so it's going to be loose it's still going to be wet yep so you can put it i mean is that how you do it then you put put it in. That's exactly how I do it. I'll mix up some 30-minute epoxy in a small batch, not a big batch. And then I'll put the hinges in place, slide the control surface onto those hinges in the airframe. Excuse me.
[27:56] And then I'll slowly flex that control surface, not quite to its max travel, but at least 10, 15 degrees at least. Not quite to its max travel, but at least, 10, 15 degrees at least. And what that does is that sort of moves those hinges in the pocket so they all get in alignment and all happy together. And so they're not binding because once it's dry and once it's cured, you're not going to be able to move it at all. Yep, you're done.
[28:17] Not as easy to remove if you ever need to recover. They do require quite a bit more work to remove if you ever have to get to a point where you need to recover it, or you want to get the control surface off, whatever that reason is. So with the, putting the petroleum jelly and stuff on that, is that difficult to make sure you don't get it? Like, because I can see putting jelly on it, putting the stuff on to make sure
[28:42] that it doesn't stick, but then how do you wipe it off to where you don't get the epoxy on it? Because the epoxy is going to ball up a little bit, right? No, I understand what you're saying. So the way I do it, and this is, gosh, I did it again. It's okay. The way I, I must have to scratch my ear so I can think, I don't know, a subliminal thing or something. Turning the gears inside. Exactly. They're stuck, so I've got to get the cogs moving.
[29:08] Anyway, the way I do it is I have my hinge pockets cut, and I've got my hinges installed, and I've got everything dry fit. I like how everything is looking. What I do right before I glue it is I'll take, in this case, Vaseline on a toothpick, and I'll just kind of brush a little. It doesn't take much. I mean, you don't need a lot.
[29:31] Just a little bit on both sides of the—so I'll flex the hinge all the way over, put a little bit of the Vaseline there, and then I'll flip the hinge over and do the same thing on the other side. But a real trick way to do it is to take like a— A trick way? Yeah, a really slick way to do it is to take a baby food jar lid or any kind of small metal lid, put some Vaseline in that, and then set your covering iron in a vise or something so that
[29:58] the shoe is up. And you set that lid on that shoe at a medium setting or so, and it'll liquefy that petroleum jelly. And you just simply dip the hinge, fold the hinge over and dip just the hinge line in that jelly and pull it out and you're good. Do you do both sides? Do you flip it? I do. Yeah. Yep. Just to make sure I've got as much in there as I need. And then you've got a permanently lubricated hinge. You don't have to remove that vaseline at all. You just leave it
[30:24] in there and it provides a nice lubrication for that pin. That's a good idea. I might have tried those one day. I don't know yet. We'll see. I'm a big fan. They're not my favorite hinge. We're getting to that. But those are really good quality hinges. And Dubrow, I've been using Dubrow hinges forever. And they work really well and they operate really, really, really smooth. That's what I like about the pinned-style hinges.
[30:48] So, well, let's talk price afterwards, like cheapest to most expensive. I don't know, but let's get through all of them first. We don't have that much left. So the next one is my favorite. It's a variation of the flat pinned-style hinge. This is a hinge that's called a pinpoint hinge. Robart makes them. I think there's a few other companies that make them. They're basically just a round hinge or a round piece of plastic that has a pin in the middle, just like a pinned hinge, except these
[31:17] are round. They're very, very strong. You do require a technique to install them, but they are super, super strong. And they're really, really versatile too, depending on the angle that you install them. Like you don't have to install these in line. You can have, the hinge protrude, I say, out the bottom of a trailing edge and then back up to the, the other control surface. So you can actually have a control surface that kind of has
[31:45] a fowler type actuation. Oh, so when you say in line, it didn't have to be on the center line of the control surface. Exactly. I got you. Okay. Yeah. So your hinged line can be wherever you want it to be. And that's the beauty of these things is that they're not a flat piece of plastic that you have to figure out how to mount. It's just a hole with another smaller or another slightly larger hole to accommodate the point. Why can't you do that with the other type of hinges?
[32:10] Well, you can, you certainly can, but it would look a little awkward. Let's say you wanted to do a Fowler type actuation. Which, what does that mean? So that's where the control surface, instead of just being hinged, you hinged to just go up and down, it actually comes kind of down and out as it actuates, like a flap, for example.
[32:33] Instead of just being hinged to where it just goes straight down, a Fowler actuation actually, as it moves, it actually kind of pulls away from the leading edge or the trailing edge and comes down at the same time, kind of like the flaps on the line. On that eFlight air tractor? Exactly. And so you can accomplish that by actually drilling a hole. Instead of in line with your hinge line, you just come down below, and your hinge is actually at some weird angle to your trailing edge exposed.
[33:04] So it's not in the hinge actual joint. And then, your control surface, the other hinge goes up to the control surface and then they sort of operate at an angle, which is pretty slick. I understand a little bit what you're saying then. Yeah, it's much like if you Google Fowler flap operation, you'll see what I'm talking about. And that would be hard to do with a flat hinge because then instead of just simply drilling a hole to glue the hinge into, you have to figure
[33:28] out a way to put some sort of a flat, wide slot. And then you have that flat, wide hinge hanging out there in the airfoil, as opposed to something round and streamlined. And so the other thing, I guess, then, that judging by the way you're talking, that would make that easier, is the fact that they're longer hinges? They are. And that was another point I was going to make. So they require a deeper pocket because the hinge is much, much longer than a flat style hinge,
[33:56] because the hinge actually resembles a rod that's, say, on a Robart 40 size, their standard medium size, I think is what they call them eighth inch hinge the hinge itself from one end to the other is probably pretty close to two and a half to three inches long total so you can see the it requires quite a bit more structure in the hinge pocket so for that side then is and a half yeah roughly inch and a half or so yeah as opposed
[34:26] to a ca hinge which is like an inch overall might be maybe it might be a half an inch on either side of the center yeah okay so it requires more structure for the hinge to be glued into but because of that a side effect is that they are stronger so you may have to like if you're going to retrofit an older airframe you'll'll want to make sure that there's material enough for that hinge to grab a hold of, preferably all the way.
[34:52] These hinges are barbed on either end, so they're designed to hold onto the structure with epoxy. So you'll want to make sure that if you're going to retrofit an older airframe that you actually have enough material to glue these hinges to. But in a new build, it's easy to do. Like on my dualist, I use these on my dualist. I just added material to the trailing edge of my horizontal stabilizer, for example, so that I knew I had enough engagement for that hinge, if that makes sense.
[35:24] Yeah, I understand. So the pocket is long enough for the drill bit to go into? Exactly. So you're not drilling into air? Into air, right. Yeah, okay. So they do require a technique to install, which is not very hard. Actually, Robart, for their hinges, they sell a tool designed just for their hinges that makes it pretty foolproof. I can do it, so I think just about anyone else can. But like I said, it does require a little bit of a technique.
[35:51] But once you've got it down, it's super easy to do. You drill, in the case of the Robart eighth-inch hinge points, you drill an eighth-inch hole, and then because the center of the hinge is a little bit thicker than the points themselves, you come back and you counterbore another 16 i think it was just deep enough to accommodate that hinge pin area kind of like on a flat hinge how you have to yeah flat and recess same idea here but yeah once you do that
[36:17] man you slide these things in there and they are super super strong and then just like they are a little more critical for alignment because you don't have that nice wide flat area to sort of, you can go oversize on your hinge pocket a little bit to give the hinge room to self-align, when you flex the control surfaces. The hinge points are much less forgiving of having them not in alignment. And by alignment, you mean horizontal alignment. Exactly.
[36:49] Like on a horizontal stab or something, you're talking about side to side, not up and down. Exactly. Okay. Yep. So other than that, once you develop your technique and you've got the installation down to a T, they're really nice hinges, and I like them because they do operate very, very smoothly and they are super strong. Again, because these are a pinned hinge, the hinge, the joint requires protection just like the flat hinge did from the adhesive,
[37:17] in this case epoxy. You can really only use these with epoxy. But yeah, same principle applies, a little Vaseline on the hinge, joint there of the hinge will protect it from the epoxy. These are probably the most difficult to remove if you ever need to remove the control surface. That's nice. That's good to hear. That's what my big yak has on it. That's what I got to take apart yeah well i mean usually because of the how smooth they operate and the way they operate
[37:52] usually you can open these up like when you disconnect your control linkage you'll usually have enough flex or enough opening in that in that hinge area that you can usually get by with recovering these without actually having to take them off the airframe. And that's one, in my opinion, one advantage of this hinge is because you don't have that nice wide flat area to try to work covering around. It's just
[38:17] a small little eighth inch wide hole, essentially, that is usually pretty easy to recover in place. Do they come bigger than eighth inch yeah i think robar makes them in three sizes they make like a small half a like small airplane size and then the eighth inch which kind of covers everything from 20 size to big airplanes and then they make a i think they call it a quarter scale size but they're actually
[38:44] three sixteenths diameter hinges and that's probably what's on your yak i was gonna say the ones on my act look bigger than eighth oh yeah yeah that's probably the the robart three sixteenths ones the big ones yeah okay yep so but there's other companies that make them too i i don't i can't think of the names off the top of my head but i've seen some of the yards that come from overseas have pinned hinges in them too and i'm
[39:05] sure those aren't robart hinges they're probably some other copy probably like a rabart or something yeah but yeah this is my favorite hinge i really like these i like but i like to tinker so i like the fact that it requires tinkering to install them and get them set up. And these are probably the hinges that I'm going to try to use on our tri-motor project. Oh, you think so? I think so. We'll be able to get a scale-enough look with them? Oh, yeah. Oh, absolutely. Yep. Okay.
[39:38] Well, another nice thing about these hinges I didn't mention is that with the Robart hinges, you can actually recess the hinge, say, into the trailing edge of the horizontal stabilizer, and then you can create a rounded profile into the leading edge of the elevator, and then you can actually kind of slide those two inside each other. And as long as your center line of your hinge runs, the center line of the leading edge of the hinge on the elevator you can
[40:05] actually have an actuation where you never get a hinge gap ever because it's just rotating kind of like a ball and socket kind of a thing well that's kind of like so that medium-sized yak that i bought yeah we were looking at that before and i don't know what kind of hinges are on that but that is completely like self-contained yeah and there is no gap whatsoever so it's actually like a rounded front on the ailerons and then a completely
[40:32] concave rounded area that it sits in the inverse of like a long pin that goes through the whole thing yeah those are those are a hinge that that's not a hinge that you're gonna buy like in a package that's a hinge that's designed into the airframe. Yeah, just by looking at it, that is one that is designed into it like before they even start to build the airplane, they know that's how it's going to be done because you can't add it later. Right, exactly. It has flat pieces.
[40:59] In the case of the Yak, they're fiberglass. Actually, fiberglass plates coming out of the trailing edge of the wing and then fiberglass plates glued to the leading edge of the ailerons that then kind of come over and they lap together and then a hole drilled continuously through all of the hinges and then joined by one single hinge pin. Which is actually kind of nice. I like that. It's really slick. I
[41:19] like that. I like that layout, but that's something that usually has to be incorporated into the design of the airplane right from the beginning. Well, it would definitely be the most difficult, I think, to make to get all those lined up because you don't get two chances at it. So I think that would be like CAD designed into it. But the other thing that I think would be more difficult between that and any other kind is finding the pin to go into it.
[41:42] So it's like the pin that's on those is, what do you think? That's three feet long, give or take? Yeah. So it's like a three foot long, I don't know if it's aluminum or steel or carbon fiber, whatever it is. I think the pin on that one is actually a carbon fiber rod. Okay. So it's that, but then at the very end of it, it has threads. Yeah. And then the very end of it, like on top of the threads is what is it like a five
[42:05] millimeter hex hex something like that like an allen second or allen socket wrench thing so that's completely i don't know why i messed that one up like an allen head socket wrench thing whatever but that's i mean that's a completely you can't get that hardware anywhere right not that i've seen, at least. That is specific. That was made for that airplane, yeah, for sure. So I like it, but I don't know if I would ever build anything with it just because of the difficulty with it.
[42:33] And besides that, you can replicate that same interface with Robart pinned hinges. Well, what I like about the interface with it is the fact that I can take the pins out. Yeah. So if you have like a big rudder or something you need to take off for storage or for transportation, you can use that and pull the pin out in one fell swoop. Yeah. Do any of these other ones come with like a removable pin? No, they don't come that way.
[43:01] Some of the, I think the large, they might actually be called extra large Dubrow pinned hinges. I believe those have cotter pins in them so that you can pull the cotter pins out individually for each hinge. But I've never, I don't think there's a hinge on the market that is designed to be set up the way that Yak is. But certainly you could take a Dubrow hinge, take the cotter pins out and set it up that way
[43:25] for sure yeah that would be maybe we could do that on the on this one on the big project here if we need to i mean if that's something you want to do i mean we can make it happen because we haven't built anything yet if we need to we can do it but i don't see a reason because the the rudder is what five inches on that it's's not going to be a big difference. So any other, is that like your hinges? Yeah, that's going to pretty much cover most of the standard types.
[43:54] I mean, there's lots of other types of hinges that you can buy on the market designed for various things like landing gear doors. There's hinges you can buy for that that allows the door to sort of drop away from the airframe before it actually kind of opens. It's an offset style hinge. Bombay doors, kind of the same idea. There's lots of different hatch hinges. There's lots of different types of hinges.
[44:21] But for control surfaces, I think we've pretty much covered pretty much the gamut that's available right now. So, now that we're done with hinges, how do you install them? Don't get into it too much, because I know this is audio. It's kind of hard for people listening to find out, and there will be a video showing it. But what are some good techniques? What are some good tools to use with them well so a few things like on the ca
[44:45] hinges something that makes them easy to easier i should say to slide into the slots are make sure your slot is more than just a slot use the right tool remove some material create a pocket ca hinges and flat nylon hinges the same same idea if you don't create a pocket when you slide that hinge in, you're adding thickness to the trailing or leading edge, depending on what we're talking about. And then when you cover that, you'll see that. You'll see a bump.
[45:14] You'll see a bump everywhere there's a hinge. So to avoid that, use the right tool, dig out the balsa for the pocket, make sure there's a proper pocket there for the hinge. Also with CA hinges, something that makes them easier to install is to cut 45-degree corners on all the corners. Just take a little piece of that hinge off, and that'll kind of allow it to go in the slot a little bit easier if your pocket's a little tight. Some of the hinges I have are
[45:39] rounded on the edges, too. There you go. If they're rounded, you don't have to do that. Exactly. But I know what you're talking about. Some of them literally are just like squares or rectangular pieces of whatever that material is. Yeah, nylon with the cotton flocking or whatever that is. Yeah. So yeah, CA hinges. And with all hinges in general, make sure you have a pocket, not just a slit in the wood. Well, CA though would be the only one really you could kind of get away with
[46:04] just using a slit. True. It's harder to put in, but you don't have to worry as much about it. So really for something like that, you could just use your X-Acto knife. Yep. If you had to. If you had to. That's not the preferable way, but it's a way. Yep. And then, a technique I'll use when doing CA hinges and, you plunge the X-Acto knife in there and then you've got your pocket. I take the X-Acto and I kind of slide it back and forth in the pocket.
[46:31] And I let the backside or the spine of the blade sort of kind of burnish the wood in the pocket. And I'll do that on both sides. And that helps, too, with the insulation. Well, that kind of opens it up just a hair. Keeps the bumps to a minimum. But, like, what's an arrow broach? I've heard you talk about that. Yeah, so that is a really, really neat tool. It's designed for the purpose. It's not a tool that's been adapted from other forms,
[46:58] but it's a serrated blade that is triangular in shape designed to be plunged into balsa, and it actually shears off balsa fibers and creates a pocket for the hinge. Super easy to use. It's actually kind of fun to use, especially on open framework. But because it does remove balsa, it tends to put that balsa in the structure. Oh, like in the cavity. So like if you have open structure, you might want to wait before you finish sheeting it. You might want to provide some place
[47:31] for those balsa shavings to go. Otherwise, they're trapped in there forever and they'll forever be getting on your nerves every time they rattle around. I have a few airplanes like that. So I know. And same thing goes for covering. Yeah, don't cover until it's done. Right, exactly. And that way you can get all that shavings out and not be annoyed like Tom. Yeah, you can move the hinges in after the covering, but cut the slots before you cover it.
[47:52] Yeah. That'll help you out a lot. Yeah, I can see that. My favorite tool, unfortunately, you can't get anymore, is the Great Plains slot machine. And unfortunately, that was discontinued a while ago. But man, that makes cutting slots so easy. It really does. And I tell you what, I mean, for a tool that has been out of production for as long as it's been out of production, I see a surprising number of those for sale on the RC groups, classifieds, and on eBay even. So they can still be had.
[48:24] But eventually, yeah, I mean, when you want one, one may not be available. groups classifieds and on eBay even so they can still be had but eventually yeah I mean when you want one one may not be available yeah so if you see one buy one yeah and they usually go for around 35 or so dollars or sometimes less but definitely worth the investment especially if you're gonna build a lot and especially with if you're gonna build a lot with flat style hinges man
[48:42] that tool is the cat's meow yeah it's so quick so easy and you're going to build a lot with flat-style hinges, man, that tool is the cat's meow. Yeah, it's so quick, so easy, and you're done cutting a hinge and you're ready to cut more. Yeah, exactly. You're like, wow, that was fun. I've got to cut some more. And then you're looking for more airplanes to build so you can cut more hinges with it. Just another note, how I apply epoxy whenever I'm using hinges that require epoxy,
[49:10] I don't coat the hinge with epoxy and then slide it in the slot. What I like to do is I like to take epoxy and kind of ball it up on the slot that I'm sliding the hinge into,
[49:26] and then I'll take the hinge and push it into the slot, and that pushes the epoxy in with it and leaves most of the epoxy in the in the pocket not at the top of the pocket at your hinge at your hinge line i can see how that's helpful because then you don't have all that push out coming back into the hinge the actual hinge itself okay for a flat style hinge it helps a little but on our
[49:40] pinned style hinge it helps a lot nice to keep lot to keep epoxy out of those joints that we're trying to protect with the Vaseline. Okay. Another little tip I use. Anything else? No, I think that that pretty much covers it. Be sure to check out our YouTube video. If it's not out when this comes out, hopefully Ron will get off his lazy bum and do the editing he needs to do to get it out shortly after and it'll all become crystal clear when you see the video there you go sooner rather than
[50:09] later yes exactly all right cool well then until next time i'm ron and i'm tom good night good night សូវាប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់បានប់� Thank you.
