Archive for February, 2011


Hello!

I just placed order for some modelling glue products. It may sound almost irrelevant but as I have to build up my modelling infrastructure I need to buy even such auxiliary items.

I purchased my package from Autopartner, discussed with my modelling expert colleague what to pick up.

Based on his experience I went for the following.

epoxy with 6 minutes hardening time

UHU Por glue (for Depron / EPP)

I even bought some thread locker, that is only to have safe locking of propeller bolts.

What I learned from my colleague is that for different purposes you should use different glue type. For instance on the foam plane you have to have something that does not destroy (melt or dissolve) the foam structure. Another factor is what rigidity you achieve on the glued join. In some cases you might prefer very stiff and hard join, like on an engine mount. In some other cases you would prefer some softer join that can take up some deformation without braking.

CA glue is very fast and rigid with some higher price.

Epoxy is cheaper (good argument if you need to glue bigger surfaces), forms a softer join that takes stress and vibration.

UHU Por is a so-called contact glue. This means that you apply a layer on both surfaces you intend to glue together, wait 10 minutes and then push surfaces to each other. This join will get somewhat flexible, a good way to glue fuselage and wings.

I will need to get some practice with these glue types and have experience myself. So far I could only tell what I heard and read of them.

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Easystar schematics v1.1

Hello!

I promised to update my schematics in last post, now you can find the updated figures in this post.

I decided to not have OSD in first stage build. Earlier I thought of having the Simple OSD from Flytron in the back of the plane already from beginning along with 2 amp sensors. I thought that I will connect them later. This seemed to be a great idea until I started to check out how I can do the wiring. The more I read about it the more I got convinced how bad idea is to have OSD in the back. It was almost mad idea to have it there 🙂

Now I came to my senses and decided to have OSD later and then have it in the nose of the airplane. It weighes less than 5 grams, almost nothing. Wiring is quite easy if you are an expert. For me being a total beginner it will be nice task to have it properly connected. Eventually I might even have a new firmware in it, flashing the OSD needs access, one more good reason to have it in the nose. Nose of the airplane, that is 🙂

I tried to have an UBEC for extra safety but it got out of stock lately. Since in the beginning I can easily skip it and rely on the built-in UBEC of Turnigy ESC I took away this item from my schematics as well.

I plan to have long servo wires drawn from the receiver to the nose of the plane, so that I can attach my pan and tilt servos to it when the plane is ready.

Something like this (image from RC Explorer site)

With all these modifications my simplified schematics look like this.

It is hard to get any more simple than that, I will start with very basics. As I will have two wires drawn to the front I will be able to add OSD and FPV equipment without opening up the fuselage.

The only concern that I have right now is about RSSI connection to OSD. If I don’t find some workaround solution I might need to cut a hatch to the receiver later. This is possible, not a major issue.

Best regards,

Sir Crash a Lot

Hello!

I am about to order some parts for my Easystar build. Some of them are build material, others are missing components of the plane. Source of purchasing is Hobbycity.

For the motor and servo installation I will need some shrink tubes. It is better to have a shrink tube on the motor first and have the glue on the plastic shrink instead of glue the motor directly in the plane.

Same applies for the servos, it is easier to change the servo if it might fail. I purchase 30, 40 and 50 mm shrink tubes.

I will need servo lead extensions. I was not fully sure which type of connector do I have and need. I found a site which explains it well, can recommend to check it out here.

I will need JR connector as it looks like. Just to be covered for the future I will buy 20, 30 and 40 cm long cables both from JR and Futaba style leads.

I will need an ESC or electronic speed controller. I have a 40A Plush variant that I used in my helicopter. It is rather large and heavy for this plane, no need for this huge one. I could use a 25A variant. Lighter, smaller. I go for this, since I will have the ESC in the airflow, so a slimmer one will give me better (lower) drag, so I can glide better.

I purchase an ESC programming card as well. Without it you can program the ESC by moving the throttle stick and listening to beeps. Very complex operation. With the programming card you can see LED lights and set it very easily.

The main attraction of this shopping is the electric motor. A brushless inrunner with 2200 kv. This will propel my Easystar with furious power compared to the stock brushed motor.

I am short of 1 servo. Bought 3 pieces metal gear servo last time when crashed my helicopter. However for this build I will need 4 servos. So I buy one more servo.

For stocking up build material I buy some pushrod connectors.

The other main attraction is going to be the propeller. Instead of the stock one I will need 6×4 propellers that manage the power and revs of the brushless motor.

Found a very nice beech wood propeller in this size, I like the wood looks.

Just for the safe side approach I buy a plastic prop as well, in case if the wooden might not work out well.

I will need propeller adapter to secure the prop on the motor shaft.

Wanted to buy an UBEC but all of a sudden it is out of stock, so I skip that for now.

I got some present even! A colleague who is expert in RC flight gave me some piano wire pushrods with matching brackets. This will be great for my aileron mod on the Easystar.

I think with these items the build is possible. I skipped the idea of having OSD from beginning. After studying the wiring of Flytron OSD and considering the weight of it (less than 5 grams) I decided to have it in the nose of the plane. Much easier to set up, to do eventual firmware update and connect everything. This will simplify the whole build.

I will update my schematics, in a separate post you can see the updated (and more simple) plan for the electronics. The missing UBEC implies update on schematics, another good point to update.

I will get back with more info upon the arrival of my package.

Best regards,

Sir Crash a Lot

Easystar schematics v1.0

Hello!

In last post I showed you my shiny new aircraft, in this one I will publish my shiny new schematics.

I colleague of mine is great expert in RC flight and he created such a mapping of what does he need to have. He intends to build a much more complex system with stabilization, real good OSD and some sensors even. So his schematics are really advanced. Mine is more like something basic, still I thought that this could drive some order in what I do.

This setup would include first of all an UBEC for safety reasons. This would enable me to have backup power if the ESC might fail. UBEC does not equal to Union of Banana Exporting Countries, it means something else. It is a power supply that handles current for power hungry components other than electric motor. One example here.

Other interesting item is an OSD. That means on-screen display. I chose (so far) the Flytron SimpleOSD XL Edition v2. This can do some important stuff that I look forward to.

It can for instance monitor 2 batteries. I plan to use 2, one for driving the plane, one for FPV. This will get less interference. It is always good to know how much capacity you have left, specially if you plan to glide for longer time. Simple time calculation will not work in this case.

Secondly it can monitor RSSI data, this will enable me to see when does my radio link lose fidelity, when it is time to turn back for sure.

Thirdly it can do some basic GPS functions even. I don’t know if I will use this, could be good later.

What I need to check out is how to connect these in reality. Schematics help quite a lot but details are not there yet. I also need to check out how to connect current sensors. I will need 2 of these, so that OSD can count how many mA are used up from the battery.

I also need to know how big UBEC do I need. No idea yet, I will do research on this. Notice the question marks on schematics.

My intention is to build the plane so that I don’t need to cut holes on it later. So I try to build in everything that I might need in the beginning. So I might need to get current sensors and OSD prior to build it. Or I can insert them later, I need to learn more about this as well. A lot to learn, as it looks like. It is highly possible that I will come back with v1.1 and other versions of my schematics.

If anybody wonders what program I used for this schematics I can recommend OpenOffice and its Impress component. It is comparable to Powerpoint, a bit different. But it is freeware.

I hope my schematics is not full of errors. Consider it as a work in progress, not final version at all.

Best regards,

Sir Crash a Lot

Hello!

Let’s begin in medias res. Great news, my first two packages arrived. One containing the airframe, the other some accessories. First came from Autopartner, second from MJ Hobby.

I read earlier that Multiplex is doing excellent job when packaging their products and their crate boxes are surprisingly small. So I anticipated some reasonable size crate box. Of course what does reasonable mean? Specially if one doesn’t have a single clue about model airplanes and what size of boxes they do come in.

After work today I went to the local postal distribution point (a candy store actually) and fetched my package. The elderly gentleman asked me to give him some directions about the size of the package so he doesn’t need to check all of them. So I told him that he should look after some box that is longer and not so thick. Then all of a sudden he fetched a box that seemed almost large. When he gave it to me I almost threw it up in the air since it weighs nothing. As I lifted air. The element of surprise was there 🙂

I have to confess that I ordered some extra items, so the big crate box contained my Easystar and some balsa plywood and even some carbon-fibre rods and pipes.

Just for visual reference I placed my faithful little Lama v3 helicopter in front of the boxes. It looks like being parked in front of Sears Tower in Chicago or something…

My small box contains a very sharp knife (to cut foam) and some Du-Bro hinges. Sweet!

I just show how the company packed my stuff. They used already used packaging material. This is quite wise, you don’t need to scrap everything if you can reuse it. I did not get any damage, even the fragile plywood survived. So it works.

Finally, the Easystar! I do understand the comments now about how small this package is. It is small actually, very small diameter, rather long than thick. If I consider that the wing span will be 1.3 meters it seems smart packaging to me. Let’s see what is inside!

When I opened it I could see a huge sheet of nice decals. As I heard in another review “some ultra-cool stickers!” 🙂

Below that I could find a manual (detailed one), and different pieces of airplane.

The wing mounts, vertical stabilizer and horizontal stabilizer.

Steering leads and wires are glued onto top lid of package. Fuselage visible in box.

I “assembled” the plane and set Lama v3 next to it as visual reference. Rotor diameter for Lama is 340 mm. This plane is large. For me at least. Like it so far 🙂

Even Bender likes it as it seems. Who is Bender? A character in cartoon series Futurama. Created by Matt Groening, the same person who created The Simpsons. Recommended to watch.

A small box very well secured in one corner of big box contains Permax400 motor and propeller. Also different small items are kept there.

I am very happy with this package.

I need to fetch a brushless motor yet, a matching propeller. Some glue will be needed and some other hinges to do aileron mod. After that I could actually start the build. Very exciting it is, if I am allowed to use the twisted way of expressing myself as Master Yoda could have put it.

Let’s continue in next post.

Best regards,

Sir Crash a Lot