Mini Rio Rebuild

[larryrose11]

Hello all, I just thaught I would share this.
First of all, I love to build stuff, all sorts of stuff.
I liked my Mini Rio, but it had design issues I didnt like:
- The hull was too narrow. I wanted it to be more stable.
- The access to the inside sucked.
- The hatch seal had a curve in it, and made taping it difficult.
So, I am rebuilding it.
I have done a lot all ready, but Ill start from the beginning.

Rebuilding the hatch. I covered everything I didnt want to get glass on with saran wrap.




I ended up making a flange that went all the way around, and had a square front end.
I didnt ake a pic of the final glass work, but it will show up.

[larryrose11]

Widing the hull, and cut new access.

I epoxy foam to the sides of the hull, and started shaping it. I rough cut the new access holes.

I ended up glassing the foam once it was all nicely shaped.


You can see the BIG CRACK in the hull, which was a major motivator to this undertaking. I had now way to do a decent CF inlay to strengthen the hull. The yellow was Old epoxy from previous attempt to glass the inside.

[SirBudman32]

This is my daughters mini rio, upgraded with a mini mono motor a water cooled esc running a 32mm prop. Sry fro the "word at the end"

[SirBudman32]

Couple of pics of the lay out. She liked the mini mono top better so I had to make it fit.

IMG_20130205_202439.jpgIMG_20130205_202425.jpgIMG_20130205_202405.jpgIMG_20130205_202335.jpgIMG_20130205_202318.jpg

[larryrose11]

Hatch rebuild
In the first pic, I was about to lay up fiberglass on the hatch to make a flange around the outside. I did that, and a lot of other work to the hatch as well, like filling ans some priming / sanding, a LOT of sanding filler and such

Here is the bottom. you can see the original part in the inside, the white ABS plastic. You can see the fiberglass I laid up, and the filler on part of the flange on the right. The filler is there to support the curves on the hatch top, and make it fit the hull easier.






Here is the top, anll nicely filled and sanded. ready for final primer.

[larryrose11]

Motor mount.
I wanted a good way to mount and cool helicopter out runner that looked nice, and has an integrated floor mount. I came up with this.
I took 2 cooling plates, TIG welded them together, then bored and cleaned out the water passage. Threaded plugs in the side.
I sanded them till smooth, and buffed to a mirror.
My first time polishing aluminum.


Here is the water passages, drawn on the image

[larryrose11]

I have made a lot of progress, but not updated anything here. Sorry
OK!!
CF inlay, and some initial priming / filling. What you don’t see is the CF that I put on the outside of the foam in post #2. For ALL of my CF work, I use West System 207, and peel ply. I mechanically clamp it down with foam and clamps so the peel ply will squeeze the CF against the part, and squeeze out the extra resin.
Im pretty happy with how it has turned out so far.


Here she is with her lid on.

[larryrose11]

A lot of progress, updates, not so much.
She is done!! Maiden voyage is later on today, in 35 deg water.


Here is the interior: 4400KV heli out-runner, 35A Seaking, and cooling lines., Gonna run her on 3S. The battery and receiver go n the front.


The business end, X427 prop.



I didnt like the rudder pick up on this unit. It may be sufficient for smaller setups, but this is a hot setup.
The solution is to make my own through hull water pickup. The aluminum pickup tube is nested in a brass tube, so I can adjust it, meaning it doesn't have to be totally flush. I have it sticking out a few mm for the maiden run,. If the temps are OK, Ill pull it back in more.


Interior of Through hull pickup.
The reason that the CF is not totally flat, is because I had to sand the old fiberglass reinforcement out.

[larryrose11]

Turns out, the 30A ESC was not enough. I put a 60A ESC in, and man doe it run smooth!!

[larryrose11]

I have learned some lessons.
With the 4400 KV motor, with the 30A esc, on 3s. It seemed to just poop out. The unloaded RPM was high, but nothing even close in the water. I suspected this would happen.
I then upgraded to the ESC to a 60A, and nano-tec 3S battery, The speed was the same, the battery came in warm. I put a larger prop on, a X432 mm, but it went the same speed.
Battery came in hotter. Clearly, it was a lack of torque to swing the prop.
I put in a 3200 KV ADS400XL motor, and the same 30A ESC as in the pic, with a X428 prop, and WOW, It just came to life!! MUCH faster!!! Cooler ESC! Cooler batteries too!!
Here is the lesson: A lower KV motor of the same size has the ability to spin a appropriate sized prop faster, because it can produce more torque for a given current.