Tag Archive: soldering


Hello,

I am working on an exciting project. I am converting my Turnigy 9X radio to FrSky. In my other post I wrote about what parts were needed to do the conversion. Now I am trying to give a short summary of how I managed with the actual work.

As it turned out the DIY kit of FrSky is somewhat different of the one that RC Model Review tutorial uses. He used the old module, that was available by that time he made his review. The new kit has a switch for telemetry mode and firmware update.

FrSky DIY kit switch

I had to find some space for that switch. I drilled a hole on the back of radio under the metal support.

3-way switch (telemetry and firmware update)

3-way switch (telemetry and firmware update)

I faced some complication when I wanted to use my epoxy glue to fix the small circuit board with the bind switch and status light. The epoxy got wrong it the bottle, I had to discard it. Placed an order on new epoxy from local hobby shop but it will arrive only in a couple of days.

I followed the instructions when I installed the small programming board from Smartieparts. Rather easy to do. The small board that has USB connection has perfect fit in the radio back, in the battery compartment. Just slides into a cavity without glitch. This board enables even backlighting of screen, I haven’t ordered that though. So far I haven’t felt the need for lit screen.

Smartieparts USB connector 9X board Smartieparts 9X board Smartieparts board in place

Another important part was the battery upgrade. I left the original connector in the radio and cut the wire to the AA-battery compartment. Then I soldered on a servo connector to be able to use the matching connector on the Li-Fe battery pack. I not only double-checked but triple-checked the polarity. Did not want to perform inverse polarity failure.

Polarity!!!

Polarity!!!

Double heat shrink Ready to connect

I had the most trouble with the radio antenna. In the original review from RC Model Reviews that old FrSky module does not have a small washer on the antenna sleeve. The new one has. It is there for having a better mechanical connection. However it was more difficult to push through the plastic feature of my radio. I think the reason is that my radio was already modified once by its previous owner, so some of it parts were already altered. It should work most probably fine on a brand new unit. After some gentle violence I managed to get the antenna in place.

When I made the holes on the top of the radio to be able to get access to binding switch and status light I did not use any template. I just drilled one hole, put the small unit there and marked the next hole by eyeballing it. Then drilled it. And it went all right. I did not use a battery drilling machine, I only have a big machine, so was rather careful not to drill too deep into the radio. Went OK.

I received my glue so I can finalize the position of binding switch. I need to do the most tricky part of the build, the actual soldering of the DIY kit connections. When that is ready I can proceed as RC Model Reviews shows in his tutorial and build together the radio.

Soldered and added heat shrink to protect leads

Soldered and added heat shrink to protect leads

Used velcro to secure module

Used velcro to secure module

Velcro to secure module

Velcro to secure module

Module in the middle to not block metal contacts.

Module in the middle to not block metal contacts.

Bind switch "spacers"

Bind switch “spacers”

Bind switch spacer glued into housing.

Bind switch spacer glued into housing.

When all the building part is ready on the transmitter I need to refresh the software to er9X firmware as well. That will be a major leap for the radio software interface. Then I also need to change the radio receiver to FrSky on my Easystar plane. A lot of work is left actually.

As for today I checked if the radio can be turned on. It works, I did not make any fatal mistake yet. Good news, I was afraid that the “magical smoke” might get out of the radio… 🙂

With best regards,

Sir Crash a Lot

Hello,

I had to do emergency landing last time (on my 3rd flight), lost power totally. I tried to find the problem, I got huge help from my colleague who remembered a similar issue from the past. It was a cable connection that failed.

The symptoms were quite alarming, the ESC booted up normally, I could even steer the plane. But for any power input the propeller just stuttered. When it happened and I was in the air I did not notice the stuttering since air passing by rotates the propeller even at no power. Just upon the very last moment when I wanted to adjust my gliding angle became it appearent. Quite scary it was.

I checked first if the problem persists. It did persist. Then I replaced my 25A ESC to my helicopter ESC that is 40A. Same problem. This helped to rule out quite a lot of items. The only one remaining was the electric motor. This gave me a bit of headache. I just glued it back to its place since it became loose.

Maybe I broke the connection there, where it is in the fuselage? Hope not. I started to peel away isolation from the contacts that are easy to access. The first one was okay, the second one actually was so broke that when I removed the isolation the connector just falled away. The cable just broke.

I decided to resolder all 3 of them. This item was not done by me, the connectors were on from the factory. Maybe they used some wrong parameters upon soldering, I don’t know. Anyhow during last time when I disconnected the motor and glued it back the cable broke and only that stiff black isolation held it together. At low power there was some current flow there, but after 2 flights and higher current draw the electrical connection got severed and the motor just quit on me. That explains the steering also, since it happens on a different circuit it was unaffected.

Now it is fixed, I tested the motor on the balcony. There was much rejoicing on part of my wife who tried to watch TV 🙂

I put some decals on the plane, now it is easier to see it in the air. I shall test this next time when I fly.

Best regards,

Sir Crash a Lot

What is needed for RC modelling?

Hello!

Maybe it is good idea to tell what is needed for RC modelling. This is what I learned, it might be subjective and linked to my scenario. But could be a good base for rethinking.

I would definately say that you need time and money in first place. You need to have also some room for this hobby. Even if you plan to fly your model outdoors you will need to do maintenance every now and then. So “renting out” the kitchen table could be an idea. Patience is a virtue here, you will need to get to some agreement with your partner.

Tools are also needed. I picked up this hobby with very low set of tools. I bought them as I progressed and sometimes I felt limited by the available set of tools.

If you start with a RTF model kit, so it is ready to fly from the box you will only need basic tools. But if you intend to maintain, do some sort of electric work on it (change motor, servo, etc.) you will need more tools. For an RTF kit you only need some small screwdrivers and plyers.

If you intend to get further you should consider more tools.

You might even want to measure small items.

If you want to take a deep plunge in RC modelling you get into electronics sooner or later. In this case soldering equipment could be a good idea.

My favourite item is the “3rd hand” tool. It does exactly what the name implies, it shall give you a much needed third hand when you need to hold the soldering iron in one hand, the soldering wire in the other hand and the object that you intend to solder just get tossed around on the table. Before your blood pressure might get into the critical range it is good idea to use this tool.

Soldering means more tools. I started with a basic 30W soldering iron. It is very basic. You plug it in and off you go. However there are flaws to it. The tip does not warm in an even way, I cannot change the effect and working with it is very cumbersome.

So I bought a stand for it. Hoped that it helps. It solved the issue of “parking” it while being hot but the uneven warming remained.

I think the best would be to just buy a proper soldering station that can have better effect control and better overall quality.

If you are getting deeper in electronics you might use a multimeter. It can track lost connections and help a lot if you know how to use it. I don’t own a multimeter yet but plan to get one.

Of course as you get specialized to some model you might need special equipment. Helicopters need for instance a pitch-gauge to set rotor pitch. But nothing is impossible, you can survive without one in the beginning.

With some imagination and the power of Google you can substitute a lot of special tools with more simple solutions.

I was not really good at using tools earlier (still having problems), with time I can see some improvement. Practice does the trick. If you use tools while working with your hobby you get the hang of it without noticing. I don’t tell that I became Black-Belt in soldering, I would say that I am still walking on thin ice when soldering. But improving slowly 🙂

When you use tools always think twice and act after. Prepare the table for instance. Do you work with sharp items? Have something underneath so you don’t damage the kitchen table. Are you not so used to sharp tools yet? Have some first aid kit prepared. Do you start with soldering? Have clearance from flammable items, take good caution with soldering iron. It is important to enjoy the hobby but injuries and damage can be a avoided with some care. Be safe with tools.

I think that as a base package this would be enough. As you get specialized in RC modelling you will create your own toolset based on experience and personal preference. My intention is to give a base for those who just begin with RC modelling. Hope that I can help.

Best regards,

Sir Crash a Lot