whatala

Hi Phibel and opjose,
What kind of servos should I buy? HS-81? Futaba S3003 or S3004??
Thanks
Jason

opjose

Phibel DOES NOT have the same plane as you, Whatala!

This discussion really belongs on it's own thread as the confusion continues.

The EP version of the plane, which you have Whatala, needs MINI ( not micro nor standard ) servos for the most part.

whatala

Hi opjose,
MINI servo? I never heard of this term before
Is it like HS-65?
Thanks
Jason

opjose

No the HS-65 is a MICRO servo.

You are looking for "Mini' servos, approx 20-30g in weight.

These are smaller than standard servos but much larger than Micro servos.

jbarnes

Hey guys, I have the 72" C160 that I'm converting to electric after running two glows. Its a great flying plane. I also ordered the smaller EP version but have not started that one yet. I'm not really a electric guy but I've got two Eflite 25's and two 40amp escs. My plan was to put a single 4s 5000 pack in the fuse and run both motors. The 4s is a 30c rated battery. Do you see anything wrong with this kind of setup? Thanks, Jerry.

philbel

Your setup should be fine. I fly the Transall ( 7,5 pounds) with 2 x 35-48 1100kv, 2 x 60a escs, 10x5 3-blade props and a single 4s 5000 lipo. It flies very well. Landings are really scale. I put the 4s lipo right in the middle of the plane's belly, on a good velcro. I have to say this plane makes people at the club very envious! Have fun with your electric Transall.

Dangaras

I have purchased the EP version of the C-160, I plan to run 2 x TG35-36-1300KV ( I have a spare pair), MA 3-blade 10x7 props with counter rotation, 2 x 40A ESCs, 1 x 11.1, 4000mAh Lipo, 4 x DS-929MG servos, the question is, with this electric version, are the motor nacel mounts designed for the Electrc motors or does one need to purchase the HXT aluminum motor mounts to act as standoffs??

Also,does this model have the "down-right" feature built into the motor mounts? If so, then for the starboard motor, one would have to offset to "down-left" for counter rotation?

I had to make these adjustments for my nitroplanes P38 to get the counter rotation behaviour just right.

Dangaras

I got my EP C-160 today & started the initial review. There is definitely confusion about the type of servos required.

The elevator, rudder and nose wheel servos are standard servos. For example, Hextronik HX5010 (length=40mm, width=20mm) servos from Hobbyking.com drop right into the 3 servo slots in the main fuselage.

The wings require mini or micro servos such as Corona DS-929MG (mini), also available from Hobbyking.com.

I would use the HXT900 or DS-929MG or Blubird BMS-371 servo for running the nose wheel, If one chooses the mini servos one will have to pad the existing fuse servo slots with cross pieces of plywood to stop the minis from falling through.

FYI, servo classification (guideline only) as I have seen them on a few different sites are as follows;

Micro = 0-10g
Mini =  11-20g
Park =  21-30g
Standard = 31-49g
Xtra Large = 50G+

The Park group was probably initially a part of the mini servo group and recently split off with all the small park fliers and foamies that have popped up of recent.

Dangaras

I have started my build. I plan to add navigation lights & possibly flaps to this model. I will take pictures along the way and update this thread as I go for anyone interested in a similar build.

Tonight I started with the wings, I did the usual thin CA on the aileron hinges and started the inspection of the inner rear wing areas to determine if I can safely add flaps. There appears to be a solid area between the ailerons and the mounting bracket. I will probably add flaps there.

I also drilled the wing tips for the two sets of navigation lights, the strobes, the Red on the port and green on the starboard. I had to drill from the outer edge into the outer-most void area. Then I use a carbon fiber tube with a drill bit wedged & taped into it (the bit was the same size as the LED) to drill a straight set of holes through the members to the aileron servo hatch.



The LED wires are not long enough to get to the fuselage, I intend to add extensions as required. The tricky part will be mounting the driver circuit to allow removal of the wing for transport. The wiring for the motors, ESCs, ailerons, flaps & lights may make it such that the wing will not be fully removable, but unsecured and rotated to lie next tot he fuse. The loose ends are secured with masking tape to make sure they dont get lost by slipping back into the wing.

Additional pictures follow..



I have managed to mount one of the TG 35-36 -1100KV motors. I need to check the engine cowls & nacels to make sure there is sufficient clearance for the motor shaft & prop. I am waiting on some more of my ordered parts to arrive. to complete the wing assemblies. More pictures & comments as the build continues.

Dangaras

Tonight I can update on further developments of the EP build.

Once I got the one motor mounted, I started the fitting of the nacel. As expected, the Turnigy motor will require the nacel be modified to allow the TD prop mount to protrude through the front of the nacel.
 

This is the usual pain in the behind with electrics. The motors are always just too short or too long because the designer focused on one motor type. An adjustable motor mount would have been a great (yet additional expense) addition to this model.

 I will probably have to dismount the motor and add some "blocking" to push the motor forward by the few tens of millimeters required.

I was also able to get my wing navigation lights completely run through. I use 26 AWG stranded wire to extend the existing cables. The 2 ESCs are mounted behind the motor mounts with the power and control cable pulled through the front access hole. Each power cable is currently terminated in an EC3 block, but they probably will be soldered together into one traxxas male connector.

The entire wiring maze follows with close ups of the different bundles after

 

The ESCs are Turnigy 40A Sentury, the sentury connector is visible but will not be used. Best to put a large heatshrink tube on it to prevent any potential short circuits.



The servo hatches are installed with CS-929MG servos. I had to lengthen the servo arm slot to allow the servo full travel. Each servo was mounted with 3M double sided tape, then two pieces of pine were epoxied next to each servo for the screws to be inserted into for additional strength. Sorry, forgot to get the pix before I closed them up.



The starboard wing is still waiting for the arrival of the other 35-36 1100kv motor. I will use this wing to determine the padding required behind the motor to get the correct protrusion of the prop mount assembly.

jbbuggs

Thanks Dangaras i just got a cmp-160 ep and your writ up is agreat help to me. thanksfor it.

Dangaras

Jbbuggs,

no problem. I have built a few models and this is the one I chose to document for everyone's benefit. All the others (electric conversions) had different issues that I had to work around. I thought this one would be easier, but it is turning out to be as challenging as the others.

Dangaras

I managed to get some fuse work done last night. The two main servos are installed HXT5010 standard servos. The starboard servo runs the rudder and front wheel steering, The port servo will run the elevators. Notice the steering rod is installed on the right while the elevator rod is being fitted. The second picture shows the steering end linkage installed, there is a 45 degree bend in the rod to accommodate the steering arm being lower than the servo arm. The rods are new to me as they are carbon fiber with a black plug at each end that is epoxied into the end of the rod. The metal rods are then inserted into the plastic end-plugs and clamped in place with set screws allowing on the fly adjustments. The steering was designed with a screw-clamp and I do not like those, I chose to use a screw-on metal clevis to clamp to the servo arm instead.



The following pictures show the red tail and nose navigation lights, the white landing lights at the front of the main landing gear housings and the placement of the nav light controller. I will install the nav lights with a Turnigy receiver controlled switch to turn the lights on or off using a spare channel. Note these switches require a common ground, I have also included a link to the wiring diagram (http://www.hobbyking.com/hobbycity/s...X125509X52.pdf) that I made for this unit using a standard "Y" cable.






Ihave attached the PDFof the wiring diagram just in case it has been moved from it's original location...

Dangaras

I finished the installation of the servos, radio &lights, here are the new pictures:

This pix shows the Turnigy switch on the left and the Nav light controller on the right. I found using the HK packing tape is a really efficient and safe way to secure the loose wires & miscellaneous electronics where velcro would require too much volume and epoxy. If I ever have to remove them, a simple slice of the tape and the the wire or part is free.



This forward looking view into the fuse shows the AR6200 radio installed ahead of the servos with the satellite receiver off to the left at the back of battery compartment with the antennas at a 90 degree orientation to the main AR6200. I glued hollow plastic tubes to the main AR6200 receiver antenna leads to keep them from curling or getting caught up in the other wires.. The main radio was installed here to allow the servo leads to be connected without the need for extensions. Itry to make things fit without having to deal with extensions as they are one more point of failure that one does not need to worry about.




Ihave resolved the motor mount issues by adding 17 mm of padding to the front of the motor mount. Iused a few pieces of pine that Ihad lying around and covered the top with a thin sheet of plywood. The ply extends the motor by the extra 2 mm to get me past 15mm just to make sure the front of the prop assembly would extend past the front of the nacel face. Istill have to line up the motor to get the correct mounting and shaft hole alignment and dremmel the nacel face to ensure the prop mount fits without touching.

These pictures show the two pieces of pine to be epoxied horizontally with the plywood sheet for the facing. The second picutre is a close up of the un-epoxied assembly (sorry about the focus problems)............



The two following pix show the assemblies mounted with 15 minute epoxy.

Dangaras

And the build continues. My padding calculation did not take into account the curvature of the nacels and the fact that the Turnigy motors have a pretty high bell curve at the prop shaft assembly. Ihad to dremmel the entire front of the nacel away to get the motor to fit. I also had to move the motor mount mounting holes for the motor up (vertically) by 4 or 5 mm to get the motor to fit dead center in the nacel opening. Iwould suggest that other builders check this closely when using different motor types..





More picures with the motor remounted. Something to note that might affect this models flying characteristics, most models have the motors mounted with a bit of down &right angle. Ihave noticed that this motor mount looks like it forces the motor to be straight, if not at a slight "up" angle. Ihave also included the bottom view with the wiring connections and ESCmounted.



This is the view from the bottom with the nacel in place.. Snug.



Here is the view of the nacel mounted over the motor. Fits dead on.





One of my concerns is cooling for the ESC. There is no airflow ducting for air to exit. Ithink I will be opening up the intake &exhaust ports at the front and rear of the nacels. Without the airflow, Isuspect there could be some misadventure in my future. Even with the nacel opened up to accommodate the motor there needs to be an exit large enough to allow the air out. If Iremember correctly, the ratio should be inut = 1:4.... This could be an issue.



Ihave finished with the fuse assembly. Ineed to add the screen mesh to keep crap from entering through the wheel wells & Ihave to mount the HK battery alarm and LED monitor.. These things are great for making sure you have enough juice to keep flying, the alarm sceams if you don't and they tell you if you have enough with a quick glance.

This is the LED 2 to 6 cell battery monitor

http://www.hobbyking.com/hobbycity/s...idProduct=6589


This is the 3 cell audible &flashing LED alarm/monitor (there are 2 to 6 cell versions). Greatest thing short of a remote RFbattery monitor.

http://www.hobbyking.com/hobbycity/s...idProduct=7223

Dangaras

Additional details. regarding the build... I have had some time during Christmas eve, eve and Christmas eve to get some of the finishing details out of the way.

I did some extensive dremmel work on the nacels to get the perfect fit. I also decided that the dremmel had chewed up the fiberglass too much for me to leave the rough edging undealt with. I used some thin, self adhesive lead strips (used in fake stained glass windows) to create a dark border around the holes I opened up. Gives a nice finished look to the nacels. I used 20 minute epoxy and painted it on to the lead strips to make sure it stayed there permanently. As I indicated, I opened up the leading and trailing holes in the nacels to facilitate increased airflow to the ESCs. Both pictures show the nacel fitted just prior to me using the screws to fix it permanently.



The next 2 pictures show the placement of the LiPo battery monitor in the wheel housings. This allows me to see the lights during flight and hear the piezo alarm clearly. I also used screen door nylon mesh to prevent "crud" from entering the fuselage while on the ground.




The next three pix show the wing to fuse wiring bundles. I chose to coil the wire bundles under the wing and tape them in place with the HK special packing tape. This stuff is indestructible and holds like epoxy to smooth surfaces. There was an awful lot of wires to manage and I wanted to ensure there would be no entanglement in the servo arms EVER.. I also used the Hobby King servo lead clips that make sure they never come loose. Could have used a loop of dental floss, but this is easier all round for removal and re-attachment.




This third picture shows how I coiled and fixed the nav light wiring bundle on the starboard side of the fuse to keep it away from the servos. The yellow object is the nav light controller and the Turnigy radio controlled switch is below it all fixed in place with packing tape.




The next two pix show the fuse front with the battery harness and HK battery LED monitor visible. The first pic shows the EC5 connector paired into two EC3. The second pic shows the MA 10x7 3-blade props installed. I originally planned to use 11x7 props but they did not clear the fuse. I am using counter rotation here so the starboard prop is a pusher.

I performed a static power test and ran the engines up to 90%. There is sufficient power and the 3-cell, 4AH, 25C LiPo held up well over a five minute period. I need to find a luggage scale to accurately measure the thrust. For now I use the old "it took off and flew well" method based on initial 100 watts per LB estimation with minimum 25% overage calculated in.

The final work required is, install the 3-blade black spinners, figure out & build a "crud blocker" for the front wheel, fix the LED battery monitor in a permanent position for easy reading on the ground, install the ident numbers, locate the battery in the optimum spot to then aid in balancing and balance hopefully without need for additional weights.

I will post the final build pictures once I have these items complete.

The final task will be; wait until there is favourable flying weather here in Toronto to execute the maiden flight.

Some of the negative observations;

1. The rudder does not line up correctly with the rear stabilizer.
2. The amount of work necessary to fit the motors Ichose to the mounts and to the nacels.
3. The battery compartment hatch is poorly shaped and does not fit nicely into the fuselage. the problem is the poor assembly job on the fiberglass shaping and gluing used to hold the hatch together.
4. There is no hatch for the wheel openings that allows way too much crud from getting into the fuse when executing ground manouvers.

Hope everyone has a Merry Christmas.

Dangaras

In response to a question from a beginner to the hobby regarding building this model;

I built the EP C-160 (electricversion no designed for gas or glow). I would not attempt this model if you have not built a few prior to this. Being a top wing it should fly very well (some of the posts indicate otherwise). Twin motors present another challenge.


I have 10+ models and 3 of them are twins but this one still created challenges for me. The biggest issue will be the mounting of the motors and the wiring. Even being careful with my dremel I still beat up the nacels and had to do "repair" work to cover the dings.

Wiring up the two motors for starboard counter rotation, single receiver control & matching the speed of rotation can be challenging.

I still have to perform a 70% throttle static test to determine how long the 3 cell 4000mAh LiPo will last. I may have to get a second one to get respectable flight times (more than 6 minutes in my opinion).. I also think the model is nose heavy as Ihave assembled it and will require further balancing.

If there are any specific questions, I will try to answer them as best as I can.

gehr2box

Maidened my CMP C-160 Transall today. Flew very well. I bought the plane in 2006 on eBay for under $130 and was sitting on it until last month. I've read all the threads on this plane and thought I should add my experience to the mix. Got in two flights before it started raining. 8 minutes on the first and 9 minutes on the second. Take off roll and landing speed were about the same as an average glow powered sport plane. Initially I had all control throws set to the maximum and used expo to keep it tame around the center of the stick on the first flight. This is my normal practice on a new plane to ensure I have plenty of control authority in case of unexpected trim issues. I noticed a tendency to balloon with large pitch changes that I attributed to the expo curve kicking in and/or the short coupling between wing and tail. The second flight was on low rates without expo and I still found the pitch to balloon unexpectedly with larger inputs. Nothing scary, just a little more reaction then expected. Normal elevator inputs resulted in predictable pitch changes. I didn't notice any tendency to porpoise with large or small inputs. The CG is currently at 75mm. I have read that a number of people have used 75mm or more on this plane for CG, so it could just be the short coupling causing it.

Looped from level flight just fine, but don't think it will have enough power for large diameter loops. Didn't roll it yet, but aileron response indicates it will roll just fine. 60-70% power seemed to provide very scale like flight. During my stall tests I found it to be very tame. With the motors turning at a very slow idle speed and the nose held level it didn't drop a wing. It just seemed to descend slowly with very little forward speed while maintaining a level attitude. Ailerons remained effective and the glide was straight. It did not drop a wing until I abruptly applied full up elevator (I had substantial throw available). It broke to the right. The flat glide with near zero forward speed would seem to indicate that the 75mm CG is spot on.

I converted it to electric flight with the following components:

- Motors - 2 Turnigy 35-42c's (equal to an Axi 2820)
- ESC - 2 Turnigy Plush 40 esc's
- Batteries - 2 Turnigy 4000mah 3s Lipo's rated at 30C (One for each motor)
- Prop's - 2 APC 10x7 sport prop

This motor/esc/prop combo draws 36.4 amps at full throttle per my watt meter. The plane weighed in RTF at 8.5lbs. This works out to around 95 watts per pound.
After an 8 minute flight with average throttle position at 70% each battery had depleted only a hair over 2000mah, so with this setup 12-14 minute flight times should be reasonable with a little power in reserve.

I modified the kit as follows:

The NLG is junk. It consists of a very soft aluminum axle pushed onto a 5/32 hardened steel shaft and locked on with 2 set screws. No way this is going to last on a grass field. The nuts used to secure the wheels to the axles were the wrong size and would not tighten. There is no suspension or movement permitted with this setup. I grass field will transmit a whole lot of pain to the mounting bulkhead and its attachment to the fuselage. I bought a Dubro 5/32 Nose gear strut, added a Dubro EZ adjust axle, cut down the strut to size and used the trimmed off portion as an axle for the nose wheels. It fit securely and with the spring wound into the strut provides a little relief to the bulkhead when hitting the bumps on the field.

The fuselage has 3 full bulkheads in the kit I received. One at the nose, one at the trailing edge of the wing and a 3rd a couple inches behind the wing trailing edge. I managed to pull the last one loose a little with light hand pressure. I re-glued all of them with 30 minute epoxy and added a 3/8 x 1/4 hardwood longeron from the NLG bulkhead to the MLG front mount and then on to the MLG rear mount. This should distribute some of the NLG load.

The fuselage wing mounting area and hardware are not up to the job. The wing lead edge mount area of the fuselage is very week and does not have a bulkhead to help support the wing. I could flex the fiberglass that the wing front mount screw attaches to easily. In addition after the the initial installation of the wing, cracks formed on the fuselage in the center join area at the lead and trail edge of the wing mount area. I added 3 layers of 2oz fiberglass with 30 minute epoxy in this area wrapping half way down the inside of the fuselage. I also added one layer of glass to reinforce the trailing edge bulkhead attachment area. I replaced the small single wing leading edge attachment screw with a 1/4" allen bolt. The trailing edge screws provided will do in that position because there are two of them.

The engine nacelles are very light and each has a separate access cover for use with access to a glow engine. I found that the complete nacelle can be installed and removed with the electric motors in place. Since I don't need the access hatches and in the interest of adding a little more rigidity to the nacelles I epoxied the hatches in place on the nacelles. If I need motor access I can pull the prop, 4 screws and remove the entire nacelle cover in one piece. I opened up the scale turbine exhaust outlet and air inlet to permit cooling air for the motors and ESC's. I also trimmed the prop shaft opening a bit to allow more air through to the motor. I am not using spinners because they will block the cooling air needed to keep the motor/ESC happy.

My batteries would not fit in the nacelles, so I had to locate them in the fuselage. In order to do that I needed to extend the battery leads about 12" to each ESC. I read a lot of stuff here and elsewhere about surges causing failure of ESC's due to extended battery leads. It's generally recommended to extend the ESC to motor leads if an extension is needed. But long ESC/Motor leads can generate noise which can impact radio operation. One work around I read about was to add a 220uf capacitor at the ESC for each 4" of battery lead extension. The voltage capacity of these capacitors should be at least as much as the capacitors already found on the ESC. I initially thought my extensions would be 16" so I added four 220uf 50v capacitors to the battery leads on each ESC. They are soldered in parallel to the battery leads. They help absorb the surges generated by the long leads. Since my leads ended up being only 12" the protection afforded by the extra cap is good insurance. Larger gauge wire is also supposed to help a little, so the extensions are 12GA noodle wire. I had a CG problem with the battery position. The best place would be between the MLG, but that made for a tail heavy condition. I tried them at the lead edge of the wing and ended up with a nose heavy situation. My solution was to install them at an angle so they did not extend as far forward in the fuselage. The batteries are velcro'ed together and mounted in a balsa box that installs at an angle in the fuselage between the rear of the wing lead edge mount and fuselage bottom. The upper part is attached at the wing leading edge attachment mount plate and the lower part attaches on the longeron I installed to support the NLG bulkhead earlier. It's about 1 1/2" longer then the batteries to permit shifting the CG by placing foam pads behind the battery to move it aft. I cut 8 large diameter holes in the box to vent/lighten it. Its function doubles as a structural support for the wing lead edge mounting as well as the battery holder. The only downside is that the wing must be unbolted for the batteries to be installed/removed. I didn't want to cut a big hole in the fiberglass just to get at the battery easier. It's pretty light weight glass and I wanted to keep it intact for strength.

The biggest issue with this kit by far is the problem with some kits having the incorrect incidence in the precut horizontal stab mounting slot. Mine was WAY off. I had 5 or 6 deg of positive incidence in my stab slot. I had to remove a 3/8 thick wedge from the top trailing edge of the mounting slot and add that same amount of wood under the stab to fix it. After gluing the stab in position I discovered that I still had a little over 1 deg of positive incidence in the stab. Nothing I could do at that point but shim the wing or be prepared to add some nose up trim after take off the first time. I elected to do the latter.

My kit was the all white version with blue wing leading edges, red wing tips and Turkish army decals. The decals include the windows for the cockpit and side windows. They were completely unusable. The inner and outer layers separated and looked like the windows had air bubbles trapped over the black. I made some new windows from trim monokote. I had a plan to make the plane look like one of the Southern Air Transport C-130's that used to stage for Honduras out of my area in the '80s. Rather then recover the wing trim, I painted the blue/red wing/stab/rudder and lower half of the fuselage with gray Krylon and added 1/4" black pin stripping at the edges. Looks good and so far the paint is sticking without problems on the covering material of the wing and tail. I printed up the "Southern Air Transport" for the fuselage, N number and the corp logo for the rudder onto some Testors decals sheets and it looks pretty good.

I hope this info helps anyone else considering this kit. It gets a lot of attention at the field, looks great in the air and it flys pretty good too

Here is a video of the 4th flight.
[youtube]http://www.youtube.com/watch?v=XgRLQx8M2uo[/youtube]

Dangaras

I see that this thread has two different models, the Transall C-160 and the EP C-160. I have built a new EP C-160 which was designed for electric operation &not Glow..

Ihave also noticed that older models have had some major issues that have been resolved in newer revisions.

Anyone planning to build these models should pay close attention to these details as there are noticable differences and the information can crossover usefully on both builds.

Specific items:

1. The EPversion has a hatch above the nose landing gear (NLG)that is designed for the battery insertion. The Glow version requires other assembly tricks for batteries.

2. The main wing has 2 rear allen bolts and a forward protruding spar at the front that notches into the fuselage. The glow version appears to have a screw at the leading edge of the wing.

3. The EPversion is lighter and may require significantly less battery mAh to get similar flight times.

4. The horiz stabilizer - main wing incidence issue appears to be resolved..

5. The landing gear is all made of a very solid steel & the wheel collars ae perfect.

6. The fuse decals are all installed & there is no issue with adherence.

Similarities;

1. The fuse fiberglass is very soft in some places, need to be careful.

2. Need to open up the nacels to allow additional airflow for colling purposes is a must.

Dangaras

Here is an onboard video of the 2nd maiden of my C-160.

[youtube]http://www.youtube.com/watch?v=9d4lZRiaXOc[/youtube]