Projects Canadair Ct114 Tutor Build

I didn't think I would have anything to pass on until paint. But there is still a lot of little things going on. I've been working on getting a better cockpit fit. Working towards a fit that looks like a proper seam, rather than a crack. Same thing with the nose gear doors. I decided to completely redo them. The gap was way to big when they were closed and the nose gear strut was contacting the right side gear door control horn. I want the nose wheel on the center line. This meant the retract assy had to be installed to the right of center. It was, but, a 1/16" to far right. Not fun. As the nose gear support had to be redrawn and reinstalled 1/16" to the left. The door assy will now be made from .080" styrene. Next problem. How do you glue nylon to styrene? Internet search. Surehold SH-302 Plastic Surgery super glue. It is made to glue many dissimilar materials, including nylon. I should have it next week. Next modification. I weighed the plane. In theory it is ready for flight. All up weight except for paint, 6.93lb. Double the proposed weight from when the project started. I checked with my painter and he says we will add 6oz more with paint. All up weight now is 7lb 6oz. Time to repower. The 70mm fan will only put out 3lb 12oz under ideal conditions. I have found a 80mm 12 blade unit that puts out 3.5kg (7lb 11oz) of thrust. I've also found you tube video of thrust tests showing this. The fan unit should be here at the end of the month. Later I'll post pictures of the changes. BTW I have a 70mm fan unit and ESC for sale.

Don
 

Mazin

New Member
Absolutely fantastic build thread!!! I've been wanting to do more foam and after seeing this I'm gathering the parts for a couple hotwire cutters. Again great job!
 
Hi Mazin. Thanks for the shout out. Just a suggestion on your cutters. Make sure to use a spring on the tension side. I made the mistake of not using one. The spring helps to maintain tension when the wire heats up and stretches. Constant tension helps with smooth cuts.

Don
 

Mazin

New Member
Hi Mazin. Thanks for the shout out. Just a suggestion on your cutters. Make sure to use a spring on the tension side. I made the mistake of not using one. The spring helps to maintain tension when the wire heats up and stretches. Constant tension helps with smooth cuts.

Don


NICE!! I will absolutely take your advice thank you!
 
Mazin. If you have any questions, I will help if I can. Here are some glues that worked and I found foam safe on pink ridged foam board.

1. BSI 30 minute epoxy. Areas of high strength.
2. Dollar store 5 minute epoxy. Works just as good as Home Depot $9.95
3. Lepage contact cement. Foam safe, 40 minutes before putting pieces together
4. Canopy glue. Foam safe, 3 hour cure.
5. Zap CA. Foam safe, but you must use Zap kicker only or it,s not foam safe.
6. 302 Plastic Surgery. It is a CA. It bonds many materials. The only I found that will bond nylon. I had to bond some control horns (nylon) to styrene plastic.
7. Not shown. 3M 77 spray adhesive is foam safe and quick to work with. Also, a hot wire cutter cuts it as easy
as it cuts the foam. Epoxy is impossible to cut unless you turn the cutter temp up to where the foam just melts.

There are other adhesives. These are what are available in my area and worked for me.
Good luck and have fun with your build.


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Mazin

New Member
Thats awesome man thank you!! I will do what can to help out as well, i have a few tricks up my sleeve. Not a master builder but i can get by and even show a little creativity every now and then.
I'm a big fan of the foam safe CA, of course i always used normal activator with it. Just crazy cost. I've been searching the zon and other sites finding the best deals i can its jist a little slow going right now. Thanks for the heads up on the epoxy because im actually having to restock all my adhesives due to years of just being left idol.....btw thats a pia because i hate buying that stuff lol.
Again great work and thanks!!!
 
Hi everybody. I must apologize. "In theory it can fly" too broad a statement. It does look like a Tutor that is all. I forgot about the fan upgrade, the wiring, the cowl ventsand the strake. So, the fan upgrade. The 80mm was basically a drop in. Just very minor sanding of the mount to fit it in and redrill the new mounting holes. Pic. one shows installation with out its inlet ring. More modification was required to the mount for the ring. Pic. 2 shows the comparison of the 80mm fan to the 70mm fan. I thought that I need a cheater hole gor the 70mm, why not do an air intake drawing air from the bottom. Pic. 3 is the templates for the arms. I also made round templates to make the connection tom the fan. Pics. 3,4,5 and 6 are test fitting it before fiber glassing. The space between the two inlet runs is for the 6s battery. The battery fit. But, there was going to be a major weight gain to support that 1+pound battery. Also there would be no way to get the intake out if I need to remove the fan for service. Scrap the intake and back to the inlet ring. Pics. 7 show the mount with the triangle support removed and the shelf cut back so it is just behind the inlet ring. Pic 8 the mount with the triangle epoxied back on. Pic.9 is the fan reinstalled with the inlet ring. Pic. 10 the cheater hole reinforced with 1/8 plywood. Tomorrow I'll do the wiring.

Don









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Admiral

Well-Known Member
Looking good Don, you must be getting exited now you can see the light at the end of the tunnel.
 

D.O.G.

Goblin 380 Supporter
Yes sir Don. That's going to be one nice bird to fly. Can't wait to see a video of her :).
 
Thanks Keith. Thanks D.O.G. The light is not very bright yet, but at least it's on. I will post a video when I'm done the rest of the build. Hopefully it's a nice day and I can get it outside and chase some snow flakes around the parking lot.

Don
 
Fly-n-Low. Thanks for the shout out. I thought I would get the wiring posted today, but did not have enough time. Retired and time goes by faster now than when I was working. Some days I think I will go back to work for a rest. Not.

Don
 
Okay. Wiring in the fuselage. Those who have read along from the first will remember Pic.1 The 35 pin connector. The first side, the female side, sends the commands and the power to the wing. Ailerons, Flaps, Landing gear, door controller, landing lights, landing light power, navigation light power, power from the nav light controller to the nose lite and vertical fin lite, upper red beacon lite, commands fro the gear/door sequencer to the nose gear retract and nose gear servos. Pic.2 . The receiver side, the made up extensions have been labelled and soldered in place. I also siliconed all the solder joints to add insulation, vibration protection and some strength in that area. Pic 3. I made a mounting board from 1/16 ply and 3/4 tall balsa stand offs on the two ends and the front leaving the rear to get the wiring to the receiver. Glued into place with 30 minute epoxy. Pic. 4. The harness to the wing. Again the back side of the connector siliconed. The harness plugs into the wiring on the wing. No wires to be cut if one of the controllers needs to be removed. Also, the wing has to be painted and I don't want the harness in the paint. Pic. 5. The battery tray for the 6s battery. Pic. 6. Battery in place, the large red and black ESC wire on the left of the battery along with the white, red, and black throttle wire. The harness is hooked up to the receiver and to the right back to the wing. Pic. 7. Ease of connect and disconnect. Canopy off, disconnect harness, invert the plane on the stand, remove two wing bolts, slide the wing back and carefully lift up and the wing is ready for transport. Reverse to put it on. Hopefully tomorrow I'll post the last of the build.

Don





DB 35 connector.jpg Wiring 1.jpg View attachment 22635 Wiring 2.jpg Wiring 3.jpg Wiring 4.jpg Wiring 5.jpg Wiring 6.jpg
 
Nose strake and cowl vents. A strake is a piece of metal that is usually longer than it is wide. Depending on what characteristic the designer wants to achieve, it can be mounted on the nose, in front of the wing, or at the rear under the tail cone. The Tutor nose strake helps with flight stabilization. I'm sorry but I forgot to take a lot of pictures.
Pic 1. A rainy day at Base Borden to get a picture and mesurements of a strake. Pic. 2. At home nice and dry on the computer for a head on shot. Hard to see the strakes.
Pic. 3. The strake is installed. Real size is 2" wide x 64" long. 1/8 is 1/4" wide x 8" long. Using pic 1 for a starting point. I leveled the model. Marked the spot where the strake meets the light on the real plane. Took a measurement from the table to that mark. Measured back 8" on the nose and measured up from the table and put a mark at the same height as at the nose. Ran a pencil line between the two marks. Put some masking tape along the pencil line so that you can still see the pencil line. This ia the guide for the hot wire cutter. I set the depth of the hot wire cutter to 1/4" and cut a 1/16" slot 8" long. To get the curve for the strake, I used a piece of cereal box card board 3" x 8".
Pushed the edge of the cardboard into the slot at the nose light. Then traced the curve on to the cardboard. Only got about an inch of line on the cardboard. Used scissors to cut the curve. Put the cardboard back in the slot in the same place. The card board went the 1/4" to the bottom of the slot. This put more of the length of carboard in the slot.
Traced that outline and cut that curve. I did this a bunch of times until the cardboard was touching the bottom of the slot all the way along the 8" slot. Now I took this profile and transferred it to 1/16" plywood. I moved the cardboard up a 1/2" and traced the profile again. I cut the profile out of the plywood. I now had a 1/2" x 8" strake.
1/4" goes into the slot leaving a 1/4' X 8" strake. After test fitting and tweaking with sand paper, I transferred the wooden form to the plywood and cut it out. Before glueing the strakes in, I marked the position of the cowl vents. Then used the hot wire cutter to relieve the foam so that the vents can be flush mount.




Strake 1.jpg Strake 2.jpg Strake 4.jpg


Cowl Vent

Pic. 1. Lower vent. Pic. 2. Upper vent. Behind the upper vent is the electronics bay. These vents draw out the warm are and keep the temperature of the bay down. Back in the last century -1950's-, car customizers, used to stamp louvers into the hoods of the cars. When moving, air coming over the hood would draw warm air out of the engine area to help cool the engines. If you enlarge pic 1 or 2, you will see that this is a hood scoop installed upside down with the scoop still facing forward. Now air passing over it will draw warm air out of the bay. Pic. 3. Example of louvers used on cars. Pic. 4. These are 3D printed vents. I made an appointment the lab at our local library to use the 3D printer. I took pc 2 and my measurements with me to the lab. One of the techs worked with me and out came pic4 in plastic. Two hours time and the outragious price of $1.75 I have 4 tutor vents. Because the vents are installed upside down, I used .030 styrene plastic to take up the difference in height. The two plastics glued together nicely using model plane plastic weld glue. When glued in place, I have a nice flush fit. Pic 5. The lower vents are curved just like in pic 1 of the real plane. I had to shim these vents and curve them. This 3D plasic will not bend it breaks. But, if heated it can be formed. When printing this plastic is a liquid at 195 deg F. It can be formed at around 80F. I just happen to have a heat source in that is in that area. ME. Body core temp 98.6F. If a person is in a room at 70F. Skin temp is usually the same or a bit higher. Got out my infared thermometer, pointed at my thumb and squeezed the trigger. 72 and a bit. That will do it.
I shimmed the vent except for the bottom edge. I put my thumb on the lower edge and a bit of pressure. Slowly the edge started to bend. After a few test fits and thumb heat I got a good fit. Shimmed the bottom edge and glued in place. PIC 6 and 7 show the amount of curve. Pic 8 shows the final installation.
Now I'll try and get a video together.

Don



Vent 1.jpg Vent 1-1.jpg Vent 1-2.jpg Vent 2.jpg Vent 3.jpg Vent 5.jpg Vent 6.jpg Vent 8.jpg
 
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Tony

Staff member
That thing is looking better and better with every update! Loving the new ducting and the little details on the outside are fantastic!

And I know what you mean about days going by faster lol. When I made my hobby my job and worked from home (which I still do, just on a different computer now lol), days just fly by.

Keep the updates coming!!! Loving this!
 
Hi everybody. My little bird is finished. I decided to cover it in ultra cote rather than paint. Less weight.
I won't get it in the air untill next spring. If all goes well at that time I'll post a video.
Thanks for following the build.

DonIMG_1439.JPG IMG_1440.JPG IMG_1441.JPG IMG_1442.JPG IMG_1443.JPG IMG_1444.JPG IMG_1445.JPG IMG_1446.JPG
 

D.O.G.

Goblin 380 Supporter
OMG Don. That bird looks awesome. Sweet job and can't wait to see her in action next year :encouragement:
 

Tony

Staff member
Dude, that thing looks absolutely AWESOME!!! Congrats on a fantastic build! can't wait to see this bird in the air!
 
Thanks D.O.G and Tony. I hope this project will get others to build something. This was one mother of a project, but at the same time very gratifying. The next project will be a Canadair CL415 water bomber. It's from plans by a fellow in Malaysia. He does complete videos on you tube. He has many planes and the plans are free and all have video of the build. The scale of the bomber is 1:15.5. 93ft 11 inch wingspan. 72 inch model. I don't know if I can get it in the same closet as the Tutor.

DonCL 415 278.jpg water fight.jpg
 
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