Derek's New 290mm Quad Custom Build

[Derek]

I've been thinking about a new build. Something of my own. I was greatly inspired by Dan's current build....thanks for that, Dan! On top of that, since I've recently crashed my Dart 250 quad, this project just got a huge push. Originally, I wanted a speedy 400 quad. Well, I've scaled it down to 290mm diagonally from motor center to motor center.

So...I've just spent the last 45 minutes drawing up a scaled down version of my original idea. Still using the carbon fiber plate and tubing that I've already purchased, along with tube clamps, motor mounts, and nylon hardware. I'll be taking the plate and tubing to my Dad's house real soon to start the cutting with my scroll saw and his mill press.

Forgive the poor lighting, but here are two pics of what I've drawn up.

New Quad Bottom plate.jpg (46.16 KiB) Viewed 3704 times

This picture shows the bottom plate with the Naze32 in the middle, the motor mounts, and carbon tubing for the arms

New Quad Side Profile.jpg (54.3 KiB) Viewed 3704 times

This picture shows a side profile of what I expect to see when I'm done. I'll be adding a bit of curved carbon to the top plate to help protect the Mobius camera in the event of another pesky tree getting in my flight path, lol. I'm also going to have enough carbon plate in front of the FPV camera to help protect it in the event of another pesky tree. I'm also hoping that the curved carbon plate on top will help protect the battery.

[danhampson]

I like it Derek, I thought about putting the arm clamps in between the carbon plates but I was a bit concerned about space for the electronics and did think about using standoffs as well as the clamps to create a bit more space.

[Derek]

Thanks Dan! This is just a rough draft. Things may change, as they usually do, lol. I'll take the cf to my Dad's this weekend to begin cutting. I hope to have something to report back about by Sunday. I'll try to document the progress with pics as I go along.

[danhampson]

Cool I'll look forward to the progress.

[Derek]

Well Dan...after some time to think about it, I have to agree with you. I'm just going to need more room for the electronics. More specifically, the esc's. That being said, I've added a 10mm tall area, below the original bottom plate for the esc's and the usual jumble of wires, lol.

[Derek]

Some pics...

This first pic, at my Dad's. He's using a pointed router bit and a wood rip fence on his bench top mill press to cut the carbon plates in half.

1 Cutting Plates.jpg (2.14 MiB) Viewed 3681 times

The next two pics, I've got some of the holes drilled and I was test fitting the plates to the tube clamps. I put the motor mounts on, as well, just to get a view of the size of the quad. My first quad was 250mm. This one is 290 but it looks awesome so far!!!

2 Dry fitting.jpg (1.59 MiB) Viewed 3681 times

3 Dry fitting.jpg (1.55 MiB) Viewed 3681 times

.....more to come!

[Derek]

I just realized that I didn't resize the pics, like I usually do. I hope they are ok. I normally resize the pics down a bit because some "other" forums get upset with too large of pics. Sorry guys!

[cml001]

U guys & ur milling press... Jealous!

[Derek]

Thanks Clay! It's an awesome machine and I'm glad that my Dad has one.

I've done some more test fitting and I've made some cuts in the 16mm carbon tubes for the motor wires. I have to say that my cuts aren't as "clean" as Dan's, lol, but I have the cuts made and they will serve their rightful purpose and I'm happy. I'll have to either place an order or go to my LHS for some longer 3mm bolts so that I can attach the lower deck for the esc's and wires. I don't have any pictures right now but I should have some kind of update with pics tomorrow. I plan on doing some flying tomorrow but I also hope to start mounting electronics tomorrow.

Damn I love to tinker, lol

[Derek]

Here's a question for you quad guys...

How much flex with our props flex? I imagine that, at a stable hover, there isn't much flex and then if you give it full throttle, for a massive climb out, the prop tips will flex up, to some degree. I'm curious about this because I have these motor mounts for my 290 quad:

Motor Mount.JPG (10.16 KiB) Viewed 3668 times

When I add the motor and prop, the trailing edge of the prop clears the top of the motor mount by only 2mm, at best. I suppose that I could add some washers, between the motor and motor mount, to lift the motors a bit...therefore getting some more clearance. What do you guys think? How much clearance should I look for between the top of the motor mount and the trailing edge of the props?

Thanks!

[Stambo]

Did your motors come with metal mounting brackets?
Cut off the excess and use them as spacers, longer screws off course.

[Derek]

Did your motors come with metal mounting brackets?
Cut off the excess and use them as spacers, longer screws off course.

Nope...no mounting brackets. That would be an easy solution, for sure.

I also posted my question in the Mini Quad Club on Facebook. One guy said that I'm using the motor mounts upside down. If I were to turn the motor mounts over, 180 degrees, that would give me tons of room for prop clearance. I just thought that the motors should by mounted on the side of the motor mount that would have the 16mm carbon tube next to the motor so that the motor wires would go through the tube. I think I'm just going to drill a hole through the motor mounts to allow the wires to go through that hole and then down the carbon tubes....I'll just use the other side of the motor mount. I'm just a bit nervous about the props hitting the motor mount if I use the other side.

[danhampson]

by the sounds of it Derek I would drill holes through the mounts to allow the cabling to be run on the inside of the booms. Try to remove as little material as possible to try to retain as much structural integrity/rigidity.

Where abouts are you going to drill the hole in the mounting plate itself or on the centre of the mount clamp section? As for the orientation of the mounts I've seen them used both ways around. I personally would use them with the mounting plate in its highest position to keep as much of the mass as possible below the thrust line this give better stability in flight.

Nice workshop your dad has I'm jealous too.
I made up the same sort of arrangement with the wood and clamps when I cut the slots out in my top plate. Looking really good Derek keep up the good work.

[Derek]

Ok, I've drilled a small hole that is just large enough to allow the 3 motor wires to pass through the mount and then run into the carbon tube. I've drilled the hole directly in front, and center, of the carbon tube. It was the best place to drill the hole...in my opinion.

Although I was hoping to have the motors mounted so that they would sit next to the opening of the carbon tube, I've turned the mounts 180 degrees and now the motors will sit above the carbon tube and there is lots of prop clearance and life is good once again. I completely understand what you are saying, Dan, about maintaining better stability in flight. Very cool!

And yes, my Dad has a cool workshop set up in his garage. He has a very nice bench top lathe and mill press...along with some other very cool toys.

Now, I'm off to the hobby shop for some more silicone wire....

[Derek]

I spent a few hours on the quad tonight and i think I've gotten a lot done. Although it doesn't entirely look like my original idea, I'm still very very happy with it and I think this build is going to be fun to fly. I've had some ups and downs during the build, naturally, but I think I've overcome most of the downs. Here is a pic of what I have so far:

quad progress.jpg (44.44 KiB) Viewed 3649 times

[danhampson]

looking really good derek, i cant wait to flight footage.

is the plate on the top on bobbins?

[Derek]

Yes, the small plate on top is on bobbins. That's where the recording camera (Mobius or Runcam) will go

[Derek]

ooooooooooo, i'm getting that exciting feeling again, lol. This quad is nearly done. I just ordered a new Mobius camera, ALOT of props, and the Bluetooth Module. Whoo hoo!!!!

And now...the waiting game, lol

[Derek]

well...it's the usual "good news, bad news" scenario, lol.

The good news is that I've finished the build of the new "Echo 290 Quad". I just named it "Echo" because I thought it was cool. No real other reason. So..the build is done, LEDS and regulator are installed and working properly, recalibrated the accelerometers (just in case, lol), I set the configuration of the board offset 90 degrees because I have the USB port on the left side of the quad. I went to calibrate the esc's (just in case)....3 of the 4 motors turn smoothly and normally. Here's the bad news...motor number 4 (front left) stutters as bad as I do, lol. I've torn the quad down, to get access to the esc/motor wire joints, and everything looks fine and normal. This leads me to believe that I may have damaged either the motor or the esc in the Dart 250 crash (darn tree).

So...I'm going to take that motor and connect it to one of the other 3 esc's and test the motor. If it spins up properly, then I'll know that the number 4 esc is bad. If it still stutters, then I'll take one of the good motors and connect it to the number 4 esc and see what happens. If the motor then stutters, I'll know the problem is the esc. If it spins up normally, I'll know that number 4 motor is damaged.

Bummer!

Here is a video that shows off the quad a bit. It's nearly 10 minutes long. Sorry about that. I guess I got rambling on...imagine that.

https://www.youtube.com/watch?v=pjQhb9TzEfQ

[Derek]

UPDATE

OK, I got my voltage meter out and i did find that I am getting 12.1v into all 4 esc's (only needed to test the front two but I did all 4). I'm using 2mm bullet connectors from the esc's to the motors so it was very easy to swap motors and test. I took motor 2 and connected it to esc 4 and vice versa. Originally, motor 4 stuttered. After the swap, motor 2 (connected to esc 4) spun normally and motor 4 (connected to esc 2) still stuttered and then.............a bit of smoke. Bummer....but this is a clear cut story of a damaged/faulty motor. I disconnected motors 2 and 4 from the esc's and tested motor 2, again, on esc 2 and 4....motor 2 spun normally. So, I simply need a new motor. That's really disappointing but that's also the life of an rc'er. Parts have the potential of NOT working after a crash, lol. I think these motors are $17 each from BuddyRC so I'll get one ordered.