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Author Topic: Something strange on the building board (New Build Diary)  (Read 798 times)
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JeffS_NC
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« on: October 23, 2021, 10:15:15 PM »

I have been reading WAY too many posts on this site about the P30 class, and figured "Why not?" and that I would give it a shot. I was kind of inspired by marcelop's post on here about his Guillows Javelin (https://www.hippocketaeronautics.com/hpa_forum/index.php?topic=2315.0) and the recent Lancer/Javelin Postal Contest and I got to thinking (dangerous thing for me! LOL!) that the Javelin does kinda/sorta remind me of a lot of the P30's I have been seeing here on the site, so into the old toolbox and start digging out the plans I had... Of course, being a pack rat and not getting rid of anything, I still have a bunch of different plans including the Javelin.

So with a couple of home made balsa strippers, an old piece of OSB that was sitting around that used to be a desk I made, a few pieces of cardboard, some concrete masquerading as 3/32" balsa, and a lot of spare time on my hands, I got to work. Started off by stripping out some 3/32" squares and started to work on the fuselage loosely based on the Javelin blueprints, but making it 28" long instead of the 21" long on the plans. Of course, I didn't actually make up a set of plans, but I had the idea in my head. So I grabbed a couple of pieces of 1/8" x 1" by 48" long strips of aluminum that I had out in the shed that were left over from my body experiment for the racing kart to use as a jig of sorts, a whole mess of pins, and a couple of pieces of cardboard with a few lines drawn on them and started cutting 3/32" wood/concrete pieces to build the fuselage.

Figured that since it has been quite some time since I have actually attempted to scratch build a plane, that what I have so far done on the fuselage ain't too bad. Yeah, there are a few little pieces that are not 100% at 90 degrees in two planes (pardon the pun) and a couple of other pieces that are not quite perfectly lined up with the top or the sides, but overall, I'm rather happy with it. Not too bad for someone that hasn't done this kind of thing for over 20 years.

Since I am still rather old school, I went with the old reliable of Elmers glue to put everything together, thinning it down with water and using a small brush to lay down a primary coat, then using the little "two straight pins and a scrap piece of balsa" capillary glue tool to add the second/last coat of glue. Put this in between the two strips of aluminum and a couple of 90 degree ruler thingies to use them as a jig, and let everything cure overnight to try to avoid having a fuselage that was more crooked than a Politician.

I left out the rear motor mounts for right now, haven't finished off the upsweep on the bottom rails in the back, and still haven't put the front end totally together just yet. Debating on using a couple of pieces of 3/32" for the motor mount with the hole drilled into them, or 1/16" sheeting with a little "washer" of 1/32" ply as a backup on the inside to reinforce the rear motor mount. Waiting on getting a piece of 3/16" thin wall aluminum tube to put a fuse mount in the back of the tail for a DT and to get that all lined up before I add a couple more stringers and a little bit more sheeting to finish up the back end. Wondering if I might need to shorten up the front by an inch or two so that I have ample room to put a nose block and a prop on it, possibly a GG setup, so that hasn't been glued up and sheeted with some 1/16" yet either.

Any advice that I can get (besides don't quit my day job and try to make a living building model airplanes) would be great! Wondering about the overall length, the motor mounts, and anything else that you great bunch of people might see that this old Noob might be missing... I know that I need to get a set of scales so that I can actually check the weight of what I have so far (betting that it weights about 2 grams less than a brick though) and decide on what wing I want to actually put on it. Since I have been involved in drag racing and other forms of motorsports, figured that I would let that help me to name this thing. Since this reminds me of a dragster chassis in its "bare bones" state, and because of a few other ideas that I have that I will disclose at a later time, the name I have come up with is "Top Fool Dragster" or TFD for short.

So without further ado, attached are a few pictures that I have of the progress so far. I didn't really want to put a lot of pictures on here because, hey, you've seen one fuselage, you've seen most of them! LOL!
 
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Something strange on the building board (New Build Diary)
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lincoln
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« Reply #1 on: October 24, 2021, 10:35:57 AM »

It wouldn't be a Javelin if the wood wasn't heavy. ;-)

You might consider a thinner airfoil (in percent, not necessarily in actual thickness) and a lower aspect ratio. (wider chord relative to span) Of course, the wider chord will require larger tail surfaces. Here's an article on how to compute tail volume, so you know how big to make it:

https://www.eaa62.org/technotes/tail.htm

You can measure and compute the tail volume for some design that you know flies well, and make yours to the same figure. Not to worry, it's just simple algebra.  I'd look up what McCombs book, Making Scale Model Airplanes Fly says, but my copy is falling apart.

Elmers is fine, unless your model gets stuck in a tree and rained on a few times.

If you have trouble making the remaining bend in the back, try wetting the wood in the area of the bend. Maybe put a wet rag on that spot or something? After soaking for a while, the bend should be easier. You might just soak the side of the longerons opposite the glue joints, so as not to soften the glue. I admit I've soaked a bunch of wood and bent it, which is great for curvy longerons, but I haven't soaked it that close to Elmers.
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JeffS_NC
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« Reply #2 on: October 25, 2021, 08:27:52 PM »

Thanks for the tips Lincoln! Right now, I have five or six different ideas for the wing, and about three ideas for the tail feathers, so I guess that I am either going to have to pick one, or figure out a way to switch out the wings to find out what wing works best. Two of the wing ideas are undercambered ideas, one is a flat bottom, one is a geodesic design, and either one or two are cut rib style wings. Might have to narrow down the cut rib idea though. Think I have the area of the stab set from the ideas I have, now I just need to figure out which way I want to go.

Ordered up a scale over the weekend, and hopefully I will get it in a couple of days. I'm almost afraid to see how much the fuselage is going to weigh right now considering the 3/32" sheet I had, but if it is way too heavy, I can always make up another fuselage with a different idea that will be lighter if this one turns out to be only 2 grams lighter than a brick. Might have to make an order for some of the lighter stuff and get a sheet or two if the fuselage I have now is too heavy. What would be a good weight to aim for on the fuselage? I have seen some of them in posts that are as light as 7 grams, and others that are up to 10 grams. I know that it will be a total weight thing, and that the tail feathers, the wing, and all of the other stuff needed has to weigh 30 grams minus the motor, but would like to have some ideas of what to shoot for.

I ended up using a piece of 3/16" brake line to mock up the back of the fuselage just so I could get it bent and taken care of. Since it was a rather light bend and not moving a big distance, I didn't need to wet it down, so the Elmer's is safe for now. Still need to make a few more parts and pieces, and when I get it just about done and weighed, I will put a couple more pictures of it and post the weight.
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lincoln
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« Reply #3 on: October 25, 2021, 08:45:50 PM »

If I remember correctly, it's supposed to be 40 grams without the motor. If you're not competing, my guess is that you can have a model that flies reasonably well at much more than 40 grams.I don't know how valid it is, or whether it includes robber, but there's a guideline I read someplace that a scale model should be under 0.5 grams per square inch to fly well. If we assume an 8:1 aspect ratio, that would allow 56 grams. However, my guess is that a clean model like yours could get away with more. It might need more than 1on grand of rubber, though.
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JeffS_NC
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« Reply #4 on: October 27, 2021, 05:28:16 PM »

Just a quick update. Got my scales in finally, got them calibrated, put the 99% complete fuse on it, and I get a weight of 8.471 grams. Figure that isn't too bad being 1 1/8" square, 28" long, and all 3/32" concrete. Er... Balsa. Now if I can find my stupid card for the camera, I will take a few more pictures. Just need to make up a nose block and pit the aluminum snuffer tube in it, and then I will double check the overall weight. Now to start cutting out some wing ribs!
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Kevin M
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« Reply #5 on: October 28, 2021, 07:39:43 AM »

 FWIW my latest P30 fuselage woodwork, which has similar structure to yours, weighed 6.84g without the nose block. The finished model was pretty close to the 40g target, so it seems you are not too far off.
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JeffS_NC
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« Reply #6 on: October 28, 2021, 10:30:27 AM »

Ouch! That's light Kevin! Looks like I might be about a gram and a half heavy in the fuselage, but maybe I can get lucky and make up the weight difference with the idea I have for the wing and the stab... Actually have some decent 1/16" that I have made the ribs, stringers, spars, and trailing edges with, but still using the "brick weight" 3/32" for a leading edge. Tail feathers should be with the same 1/16", so hopefully they will be light. Since I have a scale now, I have been weighing each rib and all of the other pieces to make sure I am getting the lightest out of the bunch, and putting the heavier ones in towards the fuselage and the lighter ones out by the tips. Hoping that this will keep the weight towards the center and help reduce the polar movement when the plane makes a direction change.

The wing that I am working on, #1 so far, will be dead on 30" wide, and figure with the dihedral it will shrink about an 1/8", with a chord of 4 1/2" and a slight under camber. I have ideas for like 5 or 6 wings, and since I have no social life, figured what the heck, I'll make them all and see which one does best with which rubber setup and so on. The next wing that I will make will be a flat bottomed wing, 30" long with a chord of right at 5 1/4". Helps when you have a lot of plans sitting around and you can look at different wing setups!

Even if I never get the chance to fly this in a competition, it should be a fun project even as a sport flyer at the RC field! I know I am having a blast putting it together and trying out some of the ideas I have! Speaking of competitions, does anyone know if there is anything around the Charlotte North Carolina area or within a couple hour drive? Might be another month or so before I get TFD finished and tested, but I wouldn't mind trying my luck and meeting some other fliers!
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Kevin M
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« Reply #7 on: October 28, 2021, 01:08:09 PM »

Quote
Ouch! That's light Kevin! Looks like I might be about a gram and a half heavy in the fuselage

Well it took me three attempts to get it down to that on the back of some advice from members of this forum. The big difference was in selection of wood for the longerons. The 3/32" sq. I thought seemed right was too dense. The 10g motors on these don't pull too hard longitudinally.

However the previous, heavier attempts still resulted in nice flying models even if they aren't going to win competitions. I really enjoyed the process, as you seem to be doing. It can become a bit addictive.
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randoloid
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« Reply #8 on: October 28, 2021, 09:13:20 PM »

My first P-30 was 47g without motor and in my first competition I max'd out 2 of 3.

Learn to pick good air and get out there and have fun!
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lincoln
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« Reply #9 on: October 29, 2021, 02:35:53 AM »

If the air is good enough, even an 18 wheeler will fly. There's a video someplace.
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JeffS_NC
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« Reply #10 on: October 29, 2021, 04:21:01 PM »

Hey Kevin! Would love to see some pictures of your P30 if you haven't already posted them, also would love to know what the advise you got was to get it lighter! And yes, I am really enjoying putting TFD together, think that is like 3/4 of the fun for me! I have always loved doing the "small and tedious" things that most people can't stand, which is one reason I got into racing Karts and do pretty good at that. Only problem is my age and starting to have a few health issues that are slowing me down as far as going racing nowadays. All of the bumps and bangs are kinda rough on the old body since I'm no spring chicken anymore! LOL!

Just curious Randoloid, what was/is your first P30? Always good to hear of a model that is able to max out, even though the model is only half of that equation. I know doing all of the trimming and finding good air is a HUGE part of getting ANY plane to hit the max, maybe I will get lucky and start the learning process on doing just that soon enough. Gotta get TFD finished first! Still have a ways to go though.

Hey Lincoln! If you can find that video if the 18 wheeler flying, let me know... I could use a good laugh! Also, thanks for the advice that you have given so far, looking forward to you keeping tabs on me so that I don't make any huge mistakes!

Spent some time today doing the 1st coat of Elmers on the wing assembly, and after work, I am going to start to assemble it to look more like a wing and less like a firewood kindling pile! Took me about a day to cut out the ribs, then strip off a few pieces of 1/16" to the sizes I wanted, and had a heck of a time cutting out the 3/32" concrete sheet I have to make up the leading edge. Ended up having to cut three squares out to get one that I liked. Then I spent some more time doing the fancy Xacto knife cutting on the spars to accept the wing ribs. Now I remember that I always HATED trying to get the notches the right width and the right depth. After a dozen tries, I think that I got the notches cut out to the right size so that I only have a couple of thou of an inch of wing rib sticking up, which will be smoothed out to the same height as the spar as soon as I do the finish sanding on the wing. If anyone has a nice little tip about cutting out notches like that, I would love to get ideas! Might save me some time and headaches on the next project! Speaking of sanding, I still have to do some finish sanding on the fuselage and get everything all nice and squared off, and if I am lucky, I might actually get it to lose about .001 grams in the process! Still can't find my doggone card for the camera to post some pictures of the progress so far, so I will have to hunt that down over the weekend also.
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calgoddard
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« Reply #11 on: October 29, 2021, 08:23:14 PM »

JeffS_NC -

I have never heard of cutting out notches in spars to receive wing ribs.  The common practice is to notch wing ribs to receive spars.  Take a stack of ribs like those pictured and use a notching tool to sand the correct size of notches in marked locations in the ribs, simultaneously.  For example if the spars are 1/16 x 1/16 make a notch forming tool by gluing sand paper to one side edge of a rectangular piece of 1/16-inch sheet balsa wood with CA.  Trim off the excess sand paper on each side of the rectangular piece with an Xacto knife.  You can glue a fence onto the rectangular piece of sheet balsa wood parallel to the sand paper and spaced 1/16-inch back from the sandpaper to limit the depth of the notches.

If the TE has sufficient width, notches can also be sanded into the TE to receive the rear ends of the ribs using the same tool if the ribs are made from 1/16-inch sheet balsa wood. I prefer to use 1/16, 3/32 or 1/8-inch square sticks for the leading edge of the wing and stab, depending on the size of the model.  The stick can be rotated 90-degrees so that one corner faces forward. In that case, you can sand a fish mouth notch into the front end of each rib so that it fits nicely on the LE.
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Kevin M
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« Reply #12 on: October 30, 2021, 02:33:49 AM »

Here you go Jeffs_NC
https://www.hippocketaeronautics.com/hpa_forum/index.php?topic=25796.0
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JeffS_NC
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« Reply #13 on: November 02, 2021, 05:48:39 PM »

OK, been a little under the weather and haven't felt like doing much, but I did get one of the wing halves 95% complete. After spending days looking for the card for the camera, I finally found it, in of all places, the camera... LOL! Always helps to look in the most obvious places to start off. This is the first idea that I have on a wing. I have a few others, and those will be getting built later on. This was the most complex one the way I wanted it, so I figured that I would start on it first.

Calgoddard, maybe I am calling it by the wrong name, but after you take a look at the pictures, maybe you will understand why I am notching out the spar instead of the ribs. Love the idea of using a piece of 1/16" and gluing a little strip of sandpaper on it! I'm stealing that! LOL!

Kevin M, thanks for sending the link to your build! Awesome build you have there, and it has also given me a few ideas on what I need to do to lighten my fuselage up some from reading all of the advise you have gotten!

OK, since I have one half of the wing almost completed, and I found the card for the camera, here are a few pictures of the 1st wing design.
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JeffS_NC
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« Reply #14 on: November 09, 2021, 07:08:10 PM »

And we are back! Been a while since I have posted on the progress on TFD, so here is an update so far. Couple of reasons that it has taken a little bit for me to post anything is for the following reasons:

1)  People with either OCD or ADHD should NOT own digital gram scales!!! I found out that I enjoy having this around way too much, and now I see that I have weighed almost every piece that I put on TFD so far! LOL!

2)  I got another kit for a P30, and of course, since it is the "new and shiny" plane, I just had to break into it and start to put parts and pieces of it together. Before I knew it, the stabilizer and the wing were completed. Surprising how fast a laser cut kit will go together, even when you sit there and weight each and every piece and figure out where it needs to go in the plane to keep the weight all to the inside to reduce polar movement.

I got the main part of Wing #1 done, other than the sanding and covering part. I have wanted to go with the tip plates on this wing for a couple of reasons. One, they look neat! Two, I can decrease the amount of dihedral on the wing to attempt to get as much lift as I possibly can. Three, I was reading calgoddard's post on his Flat Wing P-30 (https://www.hippocketaeronautics.com/hpa_forum/index.php?topic=25280.0) and I really liked some of the ideas and arguments that he posted. Made a lot of sense to me! Measurements on the wing are 29 15/16" long and a 4 1/2" span. The tip plates will be 2" in height. Think I might have gotten this "build light" thing down a little bit, because the bare bones of the wing come across the scale at 6.632 grams.

Got the stabilizer complete except for the tip plates. Still need to cut those out, but I am debating on doing something a little different on them. I could make them out of 1/16" balsa, same as the wing tips, but I had a couple of foam plates sitting around. Next thing I know, I have a hobby knife in my hand and I am cutting out the bottom of the plate! The stabilizer was suppose to be 12" long with a 3" chord, but I screwed up reading the tape measure and ended up cutting the leading edge and trailing edge to 11 3/4" instead. Hope that I won't need that extra 1/4" of length! Kept with the "build light" theme on the stabilizer, and without the tip plates, the bare bones of the stabilizer tips the scales at 1.086 grams.

I also put a couple of pictures of the overall look that TFD will have, minus a few bits and pieces. (Top Secret stuff... LOL!) I am debating on re-doing the fuselage after reading Kevin M's post on his P-30 (https://www.hippocketaeronautics.com/hpa_forum/index.php?topic=25796.0) and all of the advise that everyone gave him to help lighten up his plane. Really not needing to reduce the weight with wing and stabilizer #1 right now, since they only weigh 7.718 grams right now, but since the fuselage does tip the scale at 8.471 grams, without the nose block or the prop and equipment on it, I figure that I need to try to put it on a diet. I guess using Craft Store 3/32" concrete sheets didn't help, and I do see a few areas where I can reduce some of the overall weight and maybe lose a gram off the total. Then of course, I could just order me a sheet or two of some lightweight 3/32" and also some 1/32" and build a lighter overall box style fuselage or maybe roll one instead. I have seen a few YouTube videos where someone is claiming to have gotten a rolled fuselage down to just under 6 grams, so if I really want to go light, that option is there.

If anyone has any suggestions or advise that they could offer after taking a look at what I have now, I would love to hear it! Still a "Noob" to doing the scratch building, which is one of the reasons I ordered up another P-30 kit to have, just in case TFD turns out to be a flop. Anyway, here are a few more pictures of the wing, the stabilizer, and a couple of overall pictures to take a look at for you guys!
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Re: Something strange on the building board (New Build Diary)
Re: Something strange on the building board (New Build Diary)
Re: Something strange on the building board (New Build Diary)
Re: Something strange on the building board (New Build Diary)
Re: Something strange on the building board (New Build Diary)
Re: Something strange on the building board (New Build Diary)
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JeffS_NC
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« Reply #15 on: November 12, 2021, 02:31:04 PM »

Getting to my least favorite part of the build process, the sanding and covering part. I know that it is some peoples favorite part of the build because it is the final step before going and trying the model out, but I suck at covering models. Started on the stabilizer, got that covered already using tissue, and now I am starting on the wings. Figure I would get the "warpy" parts out of the way first, because there is NO WAY this 3/32" concrete in the fuselage is going to warp. Any hints or suggestions on covering these things without having a wavy mess at the end would be appreciated greatly! Using domestic tissue, a glue stick and thinned Elmer's to get the tissue on, then either weighing the piece down to the board or pinning it to the board before I spray it down with 91% alcohol, and I am STILL getting warps like crazy.  Any ideas?
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« Reply #16 on: November 15, 2021, 11:39:17 AM »

JeffS_NC -

There are many different ways of covering balsa wood fuselages and flying surfaces with tissue. I will describe my preferred method, which is a hybrid of many methods used by other builders. I will break my comments into three different posts due to their length.

My tissue covering experience has been solely with Esaki tissue, which is light and strong.  It has a grain and can shrink a great deal when sprayed with water and especially when finished with nitrate dope.

I don’t ever cover with domestic tissue.  It is heavier and not nearly as strong as Esaki tissue.  I am therefore unfamiliar with how much domestic tissue shrinks. Unlike Esaki tissue, most domestic tissue I have tested did not have a grain.
 
The manufacture of Esaki tissue has ceased, but I understand from comments on HPA that there are a number of substitutes that have similar properties.

Many people pre-shrink the tissue before covering in order to reduce the likelihood that the wing and stab will warp during the life of the model.  If you go this route, there is an excellent tutorial on Youtube by Maxfliart (Tom Hallman), who is surely one of the world’s best builders and fliers of stick and tissue scale models. My problem with pre-shrinking the tissue is that the finished wings and stabs often have saggy tissue and excess wrinkles. Saggy tissue does not impart the desired torsional strength to the balsa wood frames.

I am the designer of the Three Nite P-30 which is sold as a laser-cut kit by Volare Products.  It was designed for beginners but is easily capable of consecutive maxes if built and flown per the included instructions.  It is important that beginners be able to cover the wing and stab of that model with tissue in simple fashion, with a minimum tendency for subsequent warping. Therefore, in my instructions, I describe a simple technique for covering the balsa wood frames of wings and stabs with tissue that produces warp resistant flying surfaces.  This technique is described in my subsequent post.
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« Reply #17 on: November 15, 2021, 11:47:48 AM »

This is a continuation of my prior post about covering with tissue.

I typically build the balsa wood frames of outdoor models with nitrocellulose glue (thinned Duco or Am-Droid) or cyanoacrylate (CA).  I attach the tissue with a 50/50 mixture of white glue (Elmer’s brand) and water.  Thus, if I ever want to recover the frames, I just immerse them in a bath of water for a few hours so I can remove the tissue. Joints glued with nitrocellulose or CA won’t dissolve in water. While many people prefer attaching tissue to balsa wood frames with glue stick, I have not had good results with glue stick. Inevitably some areas of the tissue do not adhere well when I use glue stick, regardless of the brand of glue stick and regardless of the amount I apply. Also, glue stick may not be water soluble, so it is not as easy to recover the frames compared to frames that have tissue adhered with thinned white glue.

I don’t pre-shrink the tissue.  I apply it with the slick side down with a ¼-inch overlap along the edges.  On the fuselage the grain of the tissue should extend lengthwise, i.e., parallel to the length of the fuselage. For the wing and stab, the grain of the tissue should extend span-wise. This alignment of the grain imparts maximum torsional strength. Easki tissue shrinks across the grain, i.e., perpendicular to the grain. You can determine the direction of the grain by tearing a small section of the tissue. It will tear easily along the grain, but it is very hard to tear across the grain.

Once the white glue and water mixture has dried overnight, I finish the tissue with a 30/70 mixture of Eze Dope and water using a soft wide artist’s brush.  Eze Dope is sold by a company called Deluxe Materials. It is available on Amazon. One bottle can probably be used to finish dozens of models so don’t be put off by its price of $17.16.  Eze Dope is proprietary formula that looks like white glue. It is odorless. The mixture shrinks the tissue. It has a nice semi-gloss finish when it dries. The flying surfaces covered and finished in this fashion resist warping.  If unintended warps appear in the finished flying surfaces Don DeLoach taught me to use a heat gun to remove them.  You will need to put the heat gun in a vice or have someone else hold it for you. This is because you need two hands to twist the flying surface while repeatedly passing it briefly in front of the stream of hot air. Don’t overheat the tissue!
 
My third Three Nite P-30 shown in the attached picture was covered with Esaki tissue using the technique described above.  It has been transported hundreds of miles between low humidity and high humidity locations and the wing and stab have not warped.

My comments are continued in my next post.

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calgoddard
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« Reply #18 on: November 15, 2021, 11:50:26 AM »

This is a continuation of my prior two posts about covering with tissue.

Be aware that balsa wood fuselages and flying surfaces covered with tissue that has been shrunk with thinned nitrate dope look much better than if shrunk with Eze Dope and water.  The finish is better and the tissue is much tauter.  However, some people in our hobby dislike the smell of nitrate dope and thinner.

Except for the flat wing of my Three Nite P-30 and Flat Iron Embryo, I always build a predetermined amount of washout into the wing tips of my outdoor models. The tip plates on the wing of my Three Nite  P-30 and Flat Iron Embryo eliminate the need for dihedral and washout.  In constructing a typical wing with dihedral, I use shims to raise the trailing edges of the wing tips from the building surface during construction of the balsa wood frames. This is permanent and more accurate than twisting flat flying surfaces during the drying stage of the covering process.

Besides the covering technique that is used, the internal construction of the flying surfaces plays a big part in resisting warps. The density and torsional strength of the balsa wood used for the LE, TE and spars can have a significant impact.  Diagonal ribs help resist warping but also make construction much more tedious. Incorporation of a tubular carbon fiber composite spar and capping ribs with carbon fiber tow can eliminate the need for diagonal ribs while still resulting in very lightweight wings and stabs. Some events require the models to be built per plan so all you can do in terms of construction is select the best wood, i.e., the stiffest wood for a given density that meets your weight budget. In some cases the rules allow adding structure, such as by enlarging the cross-section of structural members shown on the original plan.  I generally shy away from this because of the added weight and based on my assumption that designer probably knew best.
 
I hope you and others find my comments about covering with tissue to be useful. I will continue to follow your build with interest.
« Last Edit: November 15, 2021, 12:03:13 PM by calgoddard » Logged
steveair2
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« Reply #19 on: November 15, 2021, 04:02:37 PM »

Here is the link Calgoddard suggested.  It's a great video and maxiflyart is making more tutorials.

https://www.youtube.com/watch?v=A_Hap0gT9Pg
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JeffS_NC
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« Reply #20 on: November 16, 2021, 10:08:37 AM »

Thank you calgoddard and steveair2 for the tips and the link! I ended up watching the video, along with a few others that maxfliart has done, and that guy is a real master! Think I have figured out 90% of the problems that I have been having with covering. All of this time, I have not been pre-shrinking the tissue, so I ended up going up to the dollar store and bought a 20X20 canvas picture for like a buck, then proceeded to cut the picture off of it and used the frame as a tissue rack. After using the glue stick to stick the tissue down on the frame, I gave it a nice little mist, and let it sit until it dried. Come back about 30 minutes later, and the tissue shrank so much, that it broke out one of the corners of the cheap frame. No wonder I have been having so may issues trying to cover models and keep them warp free! Fixed the frame, reinforced it this time, and stuck another piece of tissue on it. Gave it a spray, cane back 30 minutes later, and this time I got a piece of tissue that I could bounce a penny off of, and yes, I did try that for grins and giggles. Cut this loose from the frame, broke out my old Top Flite covering iron, gave it a little press to get any "strangeness" out of the tissue, and sat it to the side. Cut all of the old tissue off of the stabilizer, did a little tweaking on the framework, broke out the glue stick, and started to glue down the tissue to the frame. Put the tissue on, used some 91% alcohol to reactivate the glue, stretched it out and got it nice and smooth, then pinned it down to my board. Gave it a light mist, came back after two hours, took it off the board, and ALMOST NO WARPS!!! I was amazed! Only had a slight little warp on the one tip where it raised up like maybe a 1/16" from one rib to the end rib. That I can fix! Now off to do the wings and see what happens! Thanks again guys for all the advice and help on my least favorite part of building models! I actually might start to like to cover a model now! But about the sanding part...
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