HobbyKing.com New Products Flash Sale
Tsavah's blog
Posted by Tsavah | Jul 31, 2014 @ 04:06 PM | 2,286 Views
Many, many moons ago I learned in welding class any device used to hold metal in place until the weld was completed was called either a welding jig, or fixture. Still not sure if there is a difference, but the concept of using a device to hold metal, or something else in a specific way until the bond was completed stuck with me. I have used the same concept to make foam shaping devices, but I don't seem to have a specific thread on the subject. What I do have is a collection of pictures in various threads showing some of the devices I have made and used to shape foam parts for model airplanes.

No doubt I will be making more for projects not yet started and am thinking I should share the tricks, or device types with others wanting the inspiration. That is the purpose of this "Mini-How To", a sort of show and tell thread. Hopefully those who read what I share and study the pictures will see something useful and inspire them to make jigs, or fixtures they need for their model airplane projects.

Posted by Tsavah | Jun 01, 2014 @ 03:08 AM | 3,024 Views
Was looking through some old video on Youtube and remembered an old RC Groups thread - http://www.rcgroups.com/forums/showthread.php?t=1116932

It turns out few are commenting these days, but the concept is as good as ever and very practical for anyone wanting to do a scratch build from recycled RC Park Flyer parts. Most folks new to the hobby have at least one RC airplane they have flown and either have parts that need recycling, or want to buy better parts for a new project. In my spin on the old idea you buy a plastic wiffle ball bat set from a dollar store and use the bat as a build-over plug for thin foam board. Two sheets of the Readi-board with the paper removed in plenty of foam board for the project. Your first decision is to start with a thin bat, or a fat one. Then you have to decide if you want to make a Baby Bam Bam Bat original, or a War Bam Bat. There are other options, but most will pick one of these two.

Posted by Tsavah | May 23, 2014 @ 02:15 AM | 3,191 Views
Some "bad eggs" to fly as gliders. I have been a fan of Egg, Q, Fattie, Fat, Phat, and all styles of cartoon planes. Especially if they can be flown as RC models. The original eggplanes, or egg planes are made as small aircraft models given the classic chicken egg profile. Wings, rudders, a canopy, and other details are added until the model looks like a deformed version of a recognizable aircraft. The small, plastic Egg Plane kits are very popular in Japan and many other countries. There are dedicated web sites to the models and experienced modelers scratch build aircraft that aren't yet available as kits. Some actually start with a hen egg, while others start with plastic eggs sold during Easter, or at other times. These kits are too small for RC aircraft models, but ... there are options.
Posted by Tsavah | Mar 06, 2014 @ 11:45 AM | 3,264 Views
Had another brainstorm in the form of a vision, but have yet to do any experiments to test the concepts. In short, the idea is to shape a thin foam sheet over a thick piece of glass to form a leading edge with a small gap between the top and bottom side of the foam wing. It is likely the foam sheet will need to be heated at the curve since the fold with a gap of at least 1/4" is tight enough to cause many stiff kinds of foam board to crack. What I saw in the vision was a sheet of thin foam that had thin, lightweight brown paper glued to the top of the foam sheet. On the brown paper was a thin plastic film like food wrap. A very thin layer of urethane glue had been applied to the foam sheet before the brown paper was applied, followed by the thin plastic film so a small, soft foam paint roller could be used to press the lightweight brown paper against the thin foam sheet before the fold was formed.

The purpose of the thin, plastic film was to ensure the small, foam paint roller remained clean of glue, and later to prevent the brown paper from adhering to the thick glass sheet. Once the brown paper skin had been rolled adequately to ensure proper adhesion to the thin foam board, the glass sheet was positioned to cover around 60% of the foam sheet with a brown paper skin. The remaining 40% of the foam sheet was carefully folded over the glass sheet while the glue was still flexible and hadn't yet started to set (stiffen). Another thick glass sheet was placed on
...Continue Reading
Posted by Tsavah | Feb 11, 2014 @ 06:17 PM | 3,693 Views
The focus of this build log is making an Extra Large (XL) copy of the foam toy glider called Titan by Air Hogs. The primary reason I want a larger copy of the Titan glider toy is because my old eyes don't see the details of the smaller park flyers as well as before. I can fly larger park flyers and relax without worries of becoming disoriented. Speed is also an issue for me, so I prefer slow and graceful. What this means is I need to build larger model airplanes with very low wing loading so they can be flown slowly and gracefully with little to no stress on my part. I like the contours of the Titan glider and if you have seen the many ways the original foam glider toy airplane has been modified to look like all sorts of popular aircraft, you may have a good idea why I picked it to make an XL copy. I will attach some pictures of the ideas and first steps I needed to take to progress towards the stated objective; Titan XL.
Posted by Tsavah | Dec 28, 2013 @ 05:44 PM | 3,886 Views
Made a lengthy Youtube video (16 minutes) doing a show and tell of the tools I use while constructing foam RC airplanes. Most of the home-made tools where made for thin foam shaping. Basically putting a curve in the thin foam to match a contour of an aircraft fuselage. Maybe something will be inspiring and useful for one of your builds.

Useful Foam Working Tools (RC)- Part 1 (16 min 27 sec)

Posted by Tsavah | Dec 01, 2013 @ 02:58 PM | 3,848 Views
I am currently playing around with the idea of taking a copy of the Titan toy glider fuselage (recycled foam drink cups) and making a XP-55 variant. Seen a few fantasy aircraft models in plastic, foam, or wood completed for an art project. Some were models of a XP-55 Ascender like design from a computer game called Crimson Skies, which I played many hours more than a few years ago. There are other games with sky pirate themes and a genre called dieselpunk with some interesting art. I tend to like fantasy aircraft designs that look like they would make an interesting RC airplane. Here are some drawings and a video of ideas I am kicking about.

xP-55 Ascender Project (3 min 51 sec)



Posted by Tsavah | Oct 21, 2013 @ 05:25 AM | 4,045 Views
I seem to have over looked using foam drink cups as a source of foam for cheap, thin skinned Titan glider toy fuselage clone/copy. If you have already seen the fuselage examples I made to demonstrate using foam drink cups to hack out another fuselage in the park flyer size/range, or bigger, then you pretty much know the details. The only difference is I took the fuselage of the Titan glider toy and trimmed it down to use as a build-over plug. The process is simple enough. You start by cutting foam cups into open cones by removing the bottom. You can also remove the lip for the plastic lid if you don't want to sand it down to match the thickness of the rest of the cup/cone.

The catch is the foam drink cup sections often have a sharp cone shape and don't match the fuselage plug design. I have been cutting the cone sections as needed so each cone matches the fuselage shape and the next cone section edge (diameter). I have to make as many cone sections as needed until I have the fuselage cloned, or copied. I also laminate a second skin over the first to ensure a strong, fuselage copy. From prior foam drink cup recycling projects, I know how to link cones together for the fuselage design I desire. If this is a new concept, you may want to review what I have done already and posted in my blog. The Youtube videos and pictures should help make the process easy to understand. One thing is for sure, free foam is a hard deal to beat. Especially in these days of lay-offs and cut-backs.

Posted by Tsavah | Oct 19, 2013 @ 04:38 PM | 6,001 Views
Continuing the "show and tell" of how to make a featherweight copy of the Titan toy foam glider by Air Hogs. Since this toy foam glider is very popular for RC conversion, but often not available for purchase, a method for making a clone is needed. Some want to make an RC conversion, but the toy glider isn't available for purchase. In this example the copy of the fuselage will be around 20% larger in volume, but not all that much longer than the original. The detail is in making foam rib rings, or fuselage rings out of thin foam strips, which are cut with a curve to match the fuselage shape....Continue Reading
Posted by Tsavah | Jul 16, 2013 @ 07:07 PM | 5,450 Views
If you are wondering what is needed to turn a foam cup into a fuselage of an airplane, these pictures should do the trick. If you are a paper airplane model builder, some of this will seem new, but not all that different. The foam cup becomes the skin of the airplane and rings cut from foam cups are used as internal ribs to stiffen/shape the skin, or join foam cups, or fuselage sections. You can make foam skin sections and join them together while using an internal profile frame, or outer former that ensures each section is glued to the next without a twist or bend.

Note: if the pictures are too small, click on them and a new page will appear. Use page view tools (upper right side) to enlarge as much as you want. If you enlarge the picture enough, you can see the foam cup beads, or make each letter of my comments in the picture huge.

Posted by Tsavah | Jul 13, 2013 @ 08:36 PM | 5,128 Views
Many modelers looking for small aircraft projects build dust collectors for the shelf, or display cabinet, some build rubber band powered planes, others prefer free-flight (gliders) projects, and the rest build RC models. In this thread I will be focused on the smaller airplane models made from foam coffee drink cups and other options. In a prior foam cup airplane model thread I am focused on using the larger foam drink cups common to many fast food restaurants and convenience stores.
Posted by Tsavah | Jul 11, 2013 @ 09:46 PM | 5,550 Views
The title hints at how broad this build log will be, if I can keep at it long enough. As a bit of introduction and background information, I had a brain storm, a moment of inspiration, more than a few days ago and the related ideas just keep coming. I was thinking about the cost of many ready to fly park size flyers that are too large for indoor, unless you have a huge hangar to fly in. A few do have a huge indoor space to fly in, the lucky devils, so naturally I'm jealous, or is that envious? I have to wait until the wind is near dead calm for the small Parkzone flyers. If the RC flyer is larger and heavier, I have more opportunities to fly since they can manage wind better. The catch is the price tag for most large RC airplane models is tough to manage. The cost of shipping just makes it worse.

I have loved building airplane models from an early age, but I also want to keep the cost down for materials and tools. The cost of the RC hobby is expensive even for scratch building. I know about Dollar Tree Store foam core poster board and the fan fold foam (FFF) offered in some home improvement warehouses, which is cheaper per sheet. Other options are more expensive, but offer slightly different characteristics many users like and want. So, what other sources of foam can a person use to construct free-flight, rubber band motor, or RC airplane models? One answer is foam from trash. I have seen more than a few video on Youtube that show builders taking foam packing
...Continue Reading
Posted by Tsavah | Jul 11, 2013 @ 09:21 PM | 5,045 Views
The title hints at how broad this build log will be, if I can keep at it long enough. As a bit of introduction and background information, I had a brain storm, a moment of inspiration more than a few days ago and the related ideas just keep coming. I was thinking about the cost of many park size flyers that are too large for indoor, unless you have a huge hangar to fly in. A few do, the lucky devils, so naturally I'm jealous, or is that envious? I have to wait until the wind is near dead calm for the small Parkzone flyers. If the RC flyer is larger and heavier, I have more opportunities to fly. The catch is the price tag is tough to manage.

I love to build airplane models, but I also want to keep the cost down for materials and tools. The cost of the hobby is expensive even for scratch building. I know about Dollar Tree Store foam core poster board and the fan fold foam (FFF) offered in some home improvement warehouses, which is cheaper per sheet. Other options are more expensive, but offer slightly different characteristics many users like and want. So, what other sources of foam can a person use to construct free-flight, rubber band motor, or RC airplane models? One answer is foam from trash. I have seen more than a few video on Youtube that show builders taking foam packing and using a hot wire to cut the material into thin sheets. The thin sheets are then used in a manner balsa wood sheets/boards have been used for a very long time.

I was thinking that is
...Continue Reading
Posted by Tsavah | Jul 04, 2013 @ 02:40 AM | 5,240 Views
Was watching a few Youtube video focused on Peanut scale balsa and tissue airplane construction methods and had a brain storm: cloning toy foam gliders. The reason behind the idea of cloning toy foam gliders has to do with the shortage of the toys in local stores and an itch to convert another to RC. Also, it may actually be cheaper, or better to clone the toy foam gliders than to buy them each time I want to make another RC conversion. So far the "Titan" foam glider toy by Air Hogs is the popular choice for a RC conversion project, but there are RC conversion threads for other toy foam gliders, most of which are smaller. After giving the idea of converting a toy glider to RC some thought, it hit me - a person could start with a foam box, add ribs, stringers, and a foam sheet skin to give it shape, and construct any fuselage one can imagine. The construction method removes the need for hot wire cutting devices and methods for hollowing a toy foam glider to make room for the RC gear. The foam used to make the toy gliders isn't damage resistant with the added weight of RC gear, batteries, and an electric motor or two.

The foam types used for toy foam gliders don't stand up to minor crashes and hard landings when RC gear is added, and may not hold up well as a hand chuck glider for long. This suggests better types of foam need to be used for the toys, or it would be a good idea to use better foam types to make a clone of the toy glider. Many people like the
...Continue Reading
Posted by Tsavah | Feb 20, 2013 @ 05:58 PM | 5,662 Views
I need to do more searching, but there seems to be a small aircraft designed for one person called a "Sky Mini" that looks a lot like a cartoon Cub, or similar designed aircraft. The short, stubby fuselage might be wide enough for two persons, but the very short wing span suggests it will only carry the pilot. So far, I am not having any luck finding an RC version of the craft, but even in scale it would fit within the caricatured aircraft theme. Currently I am kicking around the idea of a larger than usual copy of the aircraft. Even at 1/4 scale the model may be large for a park flyer.

The craft I am talking about isn't to be confused with other models, or airplanes with the "Sky Mini", or "Mini Sky" phrase in the name. For example; Dynam has a 500mm free flight toy called a Hawk Sky Mini EPP hand glider that is currently sold by NitroPlanes. It doesn't look anything like a Piper Cub, or another top wing, lightweight Bush Plane. Even so, the Hawk Sky Mini glider would make an interesting small RC project if someone wanted a very small backyard flyer with a motor. I have a slightly larger version of the same thing upstairs waiting for attention, but it cost a lot more then $8 plus shipping and came with necessary mini RC gear, minus the receiver and transmitter.

Posted by Tsavah | Nov 03, 2012 @ 01:36 AM | 6,156 Views
Since I didn't find a model RC airplane named Curveball, or Curve Ball, I am laying claim to the name Curve-Ball and the before mentioned variations for this idea. If you know what a NutBall, Snowball, IFO, UFO, PBF, and others of the theme are, then you already know what a Curve-ball is going to look like. The only real differences are; the wing is more of an oval than a circle, the wing tips are curved/shaped in rather than glued on, twin rudders are used, the stabilizer is between the rudders, and the motor mount can be pretty much anywhere between the rudders, stabilizer, and leading/front edge. How you attach the battery, servo, ESC, and other electronics is open to whatever configuration you have used on any round, square, and other shaped RC flying wing in the past. As far as I can tell, any NutBall, Snowball, PBF, or other flying wing design is a good place to get ideas. Also, look at how thin foam board can be shaped using heat, lamination techniques, cold rolling, or pressing methods to cause the thin foam to "remember" the desired shape with curled up wing tips.

I have had good results with cold rolling, heating, and lamination, but not so much with pressing since I don't yet have the required tools, or a low tech method that is cheap and easy to cause a shaped plank to curl up as needed at the last 1/4, or wing tip area. I prefer to keep the center 3/4 area flat so there is less mechanical trouble with the stabilizer section between the two
...Continue Reading
Posted by Tsavah | Jul 05, 2012 @ 11:11 AM | 7,742 Views
Was watching more Youtube video and came across a very interesting model called a "Bird of Prey", a Boeing aircraft. The name is taken from a research plane used to test various stealth technology concepts. The RC version is still a rare thing to see, but the flyer is very stable, even if you change a number of measurements, or lines of the test bed aircraft drawing. In short, the wing configuration is a narrow and short version of many flying "W" designs you can view in RC Groups. The flying "W", also called a Capricorn, uses a simple principle and can be flown as a single foam sheet design. To take the configuration a step further, add a long, flat fuselage to the narrow wing and turn it upside down and you have the basic Bird of Prey design in profile. The next step would be to add a top and bottom foam skin to suggest the stealth test bed of the same name. Since the flying "W" designs tend to be very stable flyers, it is reasonable to think adding a few more parts for looks won't change much.

Let me post a few Youtube video for inspiration.

Bird of Prey & The X-45 (UCAV)-USA (Super Fighter) (1 min 17 sec)


...Continue Reading
Posted by Tsavah | Jun 29, 2012 @ 06:34 PM | 8,400 Views
I have been totally taken by the work of others where a common aircraft type is exaggerated in details, or outline, and looks like a flying cartoon RC plane. I cannot help but smile when I watch a video on YouTube, or another service that features a cartoon, or phat RC aircraft. At first you would swear the little RC plane is too fat and the wings are too small to keep it in the air, or manage a take off. Low and behold the cute little featherweight foam wonder flies just fine. Well, most of them do until the wind picks up. The cartoon designs tend to be fair weather fliers due to their featherweight construction methods, but they sure are crowd pleasures. Before I start gabbing about a project I have started, I should post a few video to see if you enjoy the work of others as much as I do. In this case, the focus will be on the P-51 Mustang RC flyers in the cartoon style.


0812Q版P 51配樂飛行 (4 min 32 sec)


ey0927399 is the master of cartoon style flyers. I'm not sure were he gets his inspiration, but it may come from a cartoon about airplanes. I must remember to post that video link also. Obviously a few of his cartoon jets seem to be copies inspired from the cartoon available on YouTube. In the mean time, we have one of our own who also builds cartoon RC aircraft of a slightly different look. He also sells short-kits and plans for his creations. I really need to add the RC Groups link for some of his builds and...Continue Reading