BatBone V-tail Build

Well after a long wait I finally got the Batbone frame from Flitetest.com. I have not included a build post here as I posted one over on the Flitetest site.

Please follow this link to the build 

There are a couple of alterations that have been made after the first builds.

I have replaced the rear motors to be the same as the fronts, RcTimer 1000kv. I also increased the splay of the rear arms by changing out the nylon spacers with wooden ones as show below. One of the cool things on how I build the quad is the ability to change all angles easily.

I also decreased the angle of the motors from 40 degrees to 30 degrees. This better suited my flying capability and the yaw speed is more than enough.

Plan XV : Vtail Quadcopter ESC

The QBrain ESC showed up a couple of days ago so I went ahead and started to figure out the mounting for the VTail quadcopter. The QBrain is not a square and is a little larger than the kk2 board so it makes it a little tricky to fit.

After numerous tries, both with a single plate, with the QBrain on the same layer as the booms and on a separate layer. I finally decided on having it on a separate lay for this build.  It gives me more room to play with, however on the next build... (yes there will be another build taking all my learning from this one) I will aim to reduce the build by one layer.

The Qbrain in its new home. you can see its a tight fit around the nylon spacers.

Building up the build layers, and mocking up the landing gear

Additional holes cut on to the plates to mount the bottom plate that will hold the landing gear and QBrain.

Heli landing gear holes made and bottom plate zip-tied to the landing gear.

Hard to see, but the bottom plate screwed together with nylon standoffs and nylon screws. You can also see the QBrain double-sided taped to the base plate. The double sided tape I used is automotive trim tape.

The frame complete, now waiting on motor mounts and motors.

After crashing the 330mm quadcopter I finally went out and got some foam balls and practice golf balls to provide some extra protection from crashes.

I just cut a slot in the foam balls and pushed them onto the feet on the bottom of the arms.

I then used some 6mm wooden dowel and hot glued the practice balls on to give extra landing protection. This also allows easier skimming on the ground when Im practicing flying in different orientations.

Plan XV : The homebuilt VTail quad .... the beginning

This Quad thing is addictive ....

After the making the fiberglass sheet with reasonable success the next step was to start working out the mapping out the frame design.

The main measurement is the space between the ends of the VTail booms need to be 120mm. That is the only thing that I have to get correct, otherwise I will have prop clash.

I am using stock 12mm diameter ally tube with 1mm wall thickness. Base n the drawing I had done previously I cut 3 250mm lengths.

I am using the 110x65 plates I had made and cut earlier.  The plates will be held together with 12mm nylon standoffs ... and zip-ties.

The basic parts ready for building.

First mockup to get the general locations of everything.

Drawing out reference lines as the plates are not square from the cutting process so had to measure everything from a center line.

The first holes drilled were to space the rear boom at the correct angle.

Standoffs inplace showing how they are placed and holding the booms out. (This was later changed)

The plated taped together to transfer the holes to match on the second plate.

First full bolt down, I had to change how I held the from of the booms in the plate as the way I had planned didn't work.  I changed it to have three standoffs holding holding the front of the rear booms on place.

here you can see the three standoffs for each boom holding the front in place.

The front boom after trying may different ways is held in place with bolts. You will notice the blue zip tie at the rear of the fiberglass plates. This is there to hold the booms against the rear standoffs and to stop the rear booms from splaying

The underside plate with 20mm stand offs, there will be another plate that will house the Q-Brain ESC and have the helicopter landing gear mounted to it. The battery will be strapped to the bottom of that plate.  

I now have to wait for the additional motors (SK3 1275kv, same as the small Quad) and the motor mounts that I got from ebay that fit 12mm tube before I can finish the build.

Plan XV : Making fibreglass sheets for Vtail Quad

With my plan to try and make a VTail quad and the difficult nature of getting model making stuff at a sane price here in NZ, I decided to try and make some fiberglass sheet for quad body plates.

Since I already had the fiberglass resin and some chopped matt from my other "Summer" project I just used that. Im sure if I went and got mesh I could make thinner and lighter sheets, but for this first test i used chopped matt, and I didnt want to spend any more $$ until I can prove I could make fiberglass sheets.

After doing some googling and reading this is how I went about it ....

I had a old beach cut off that was cover in formica (hard flat surface) and a toughened glass panel from an old computer desk.

Next I worked out the workable size and then masked it off with Waxed paper. Each side had he waxed paper taped down. The waxed paper is used as a cheap release agent.

The next step was to cut some the chopped matt to fit inside of my defined working area.

I then mixed up the resin and layed down the first layer of resin and wetted out the layers of matt.

This is three layers of 1mm chopped matt wetted out and fully rolled with a fibreglass roller.

Next I placed the glass sheet on top and then walked over it all to apply pressure and hopefully get a condensed flat sheet and smooth surfaces on both sides. I then put some very heavy item on it and left it overnight in a cold garage.

24hrs later I carefully split the glass off. This was tricky and required patience and I was really nervous that it would have bonded together, but it popped apart pretty easily and I was really happy with the finish. There were some areas where is wasn't fully wetted out and there was some exposed fibre. But overall really happy with the result. Next was to get it off the base board. 

It popped off the base easily due to the waxed paper. There was some seepage. Next time I would use two layers of paper. The picture below shows the sheet fully realised.

Since it was still not fully cured due to the cold I was able to cut with a craft knife. It took about 10 passes to cut fully through the sheet. 

I spent about 30-40mins cutting out various sized plates from the sheet. The plate sizes I cut are guesses on what I think I might need. 110x110mm, down to 65x65mm. The ones for the Vtail is 65x120mm. I hope my estimates are correct. 

Overall it was a fairly easy process. But that is due to my previous learning on the TBucket and having the materials. It may not be cost effective if you had to go and buy all the materials. 

It will be interesting to see what strength the plates have once fully cure.