Scat Cat 500 - Build thread from kit

[thenated0g]

I will probably do a test on a piece of balsa sheeting and just see how well vinyl sticks.

Got the other side of the wing almost done so set them up to see how they will fit together. Looks Good. Will join with Gorilla glue in the spark and central area and than after it sets i will join them with a generous piece of S-Glass in 6oz and laminating epoxy, wrapped around that joint.


And a video of cleaning up the second wing after bagging:

 

[thenated0g]

Sitting at the pharmacy after a tooth extraction waiting for meds. What's in my phone...
Started working on the wing to fuselage connections. The wing gets 2 dowels glued into the leading edge and the fuselage gets a piece of ply with 2 holes. The trailing edge of the wing gets a piece of ply glued down to be screwed thru into the wing blocks on the fuselage. Now that those steps are done I can fiberglass around the seam on the wing. Plane is upside down in photos. Sorry couldn't reasize them down smaller on my phone.

 

[rockyboy]

Looking good!

Also, I've found that photo resizing apps for the phone are a lot easier and more convenient to use than the desktop ones!

If you're on android, here's the free one I use

https://play.google.com/store/apps/details?id=com.simplemobilephotoresizer&hl=en_US

 

[bracesport]

@thenated0g - very nice build - the Balsa looks like it is super nice to work with - Is that the full wing width, or are there more sections?!

 

[thenated0g]

Thats it, about 51" i think it says on the box.

 

[thenated0g]

Mixed up some laminating epoxy and cabosil filler, filled the area where the carbon spar was low and the corners around the tail wing hold down block so the fiberglass would have a smoother transition. Than laid down some 3 oz fiberglass across the carbon spar and some 6 oz s-glass nose to tail on the bottom. Once this sets i will do the top of the wing. also glued on the horizontal stabilizer.

 

[thenated0g]

Since this kit was originally designed for a gas setup i have been kind of guessing at electronic locations. Decided to put as much stuff forward as i can for Cg. I decided to try and flush mount the ESC in the front compartment for airflow, but cutting a hole in the ply made it pretty weak so i made a fiberglass sandwich out of one layer of 6oz s-glass and about 4-5 layers of 3oz cloth. Came out nice and strong. Needs some more trimming and an internal structure to hold the esc in place but i think it will work well.

 

[bracesport]

Every time I use the epoxy I get more excited about future opportunities! 😀

 

[thenated0g]

 

[danskis]

Of you haven't already check out "RCtimer" for motors

 

[thenated0g]

Got the main wing covered. I am just kind of guessing at battery placement as this was a gas plane originally, so trying to finish as much as i can and get as much electronics installed as i can to help figure out the battery spot.

 

[thenated0g]

Servos and linkage installed
I went with some big boy servos from Hobbyking. I didnt want to worry about them stalling out on the expected high speeds.
9kg torque fail for under $7. Analog, but metal gear. I have used about 20+ of these on various big and medium builds over the years.

 

[bracesport]

@thenated0g - I got some big boys like that for the pitcheron project!

 

[thenated0g]

Motor and esc installed, everything is installed except the radio now. Esc should get lots of airflow. Kind of guessed at motor angle, a little down and right.

I found that the plane is very balanced as it is, battery is going almost right on cg, so i glued in a piece of plywood with my standard covering of goop on the inside so i can apply velcro later.

 

[bracesport]

@thenated0g - the balsa is looking great and I am looking forward to seeing the final assembly - your fleet is growing at a steady rate - my wife wants me to cull some of mine!

 

[thenated0g]

Almost done

 

[bracesport]

@thenated0g - I am a fan of silver and this one is also a bit Ridge ratty in style (but with more power)!

 

[thenated0g]

Started finalizing electronic locations. Got the RX setup mostly, need to adjust travel to match recommended. I installed the gps unit so i can get a ground speed reading and cut a hole in the top in case the covering is actually metal and blocks signals. Because of how the wing mates with the fuselage i had to move the battery back to make room for the aileron servo and controls. This means i have to add about 170g right behind the motor to hit cg. Looks like AUW with the 1800mah 70c 4s pack is going to be 1300-1400 grams.

That puts it at 400 watts per lb which should make for an exciting 2 or 3 minutes
https://lucienmiller.wordpress.com/2016/08/10/what-size-motor-do-i-need/

 

[L Edge]

One suggestion is that you should tape the gap between the control surfaces for a/e/r. Much better control preventing the difference in pressure between upper and lower surfaces. Learn that in our first pylon race.

 

[thenated0g]

like this?
https://alofthobbies.com/control-surface-gap-tape.html