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Andy7:
19 Aug 2019 09:14:20
Good for you!  ~~
DarkButterfly:
18 Aug 2019 19:13:57
Had another negative encounter, it's been a few years since the last one, just an uneducated ******, going on about drones being illegal yada yada yada.    :-/
Still that didn't spoil my flying time, had an absolute blast  ~~
Gaza07:
07 Aug 2019 19:52:01
ooooh mrs jones  :D
hoverfly:
30 Jul 2019 15:26:34
D.B. you tightwad.. :cool:
atomiclama:
29 Jul 2019 20:14:10
DB that just means you have shed loads of props in the first place ;-)
DarkButterfly:
29 Jul 2019 18:53:33
Just had a thought, even with all the crashing I've done, I haven't bought any replacement props in over a year ~~
ched:
09 Jul 2019 19:45:42
May the sun shine and winds be light for BFU#8. Son't forget lots of vids for those of us unable to attend.  :D
Gaza07:
09 Jul 2019 18:10:30
Hope you all have a great day  :beer2:
Andy7:
09 Jul 2019 14:05:28
BFU#8 details locked in for this saturday - see the head of the forum thread for all details.
hoverfly:
05 Jul 2019 21:51:05
Good for genital warts as well......or so I'm told.. :hmm
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3d - Printworx

Printing 3d Forum

Tricopter Build WIP.

Started by JT, Saturday,June 22, 2013, 19:08:58

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JT

Saturday,June 22, 2013, 19:08:58 Last Edit: Wednesday,August 07, 2013, 16:27:30 by JT
 Much as I love my quad, I bought it ready made, I have done enough repairs and changes to it to have built it myself but its still something that I bought complete(ish). I like the idea of having something I have made myself from scratch that will fly. I have found myself seduced by the weirdness of the tricopters, its just something about the way they look in the sky that is so appealing :cool:. I';ve watched a lot of youtube and read much on the interweb and decided to build an rcexplorer style tri as the frame is easy and light looking. Having a quiet day Thursday I made a start....

I printed out templates for the centre plates and found the thinnest bit of ply I had kicking around, and nicked my kids ';pritt stick'; to attach the templates to the ply.


I cut out the templates roughly with a bandsaw and finished to the exact lines with various motorised sanding implements. I had to go out and buy some 12x12mm pse square dowel and cut some for the arms and front...


I put it all together with the thinnest bolts I had, they were M4 thread which gives a bit more weight than the suggested M3s would have but the local cost of bolts takes the proverbial p--- so I used what was at hand :laugh: The camera/battery tray was errr shall we say ';fun'; to make (well making the parts was ok but the ';fun'; was in the assembly :hmm:). After it was done I gave it a quick coat of black paint....


I got 3 Turnigy 2213N 800Kv motors and looking at the vulnerability of the wiring decided to use rcexplorers tip for strengthening the weak point with epoxy...


I have some HK 18/20A ESCs flashed with simonk that I scored from ebay and have all the necessary wiring bits and bobs on the way to do the business.  I';m short of a flight controller, servo and more desperately the bits to make the yaw mechanism (HK don';t have the brackets used in stock :cry), I want to use rcexplorers yaw design as its very simple(not much to go wrong) and will weigh next to nothing. If anyone knows where I could get some of these brackets I would be mahoosively grateful :smiley:

There will be more to come as I get the bits to continue the build ~~

Biffa

Steve

amxen

Saturday,June 22, 2013, 20:30:11 #2 Last Edit: Saturday,June 22, 2013, 20:34:28 by amxen
not a 100% on this as iv not used them but this maybe the same thing you just need 2 sets

http://www.ebay.co.uk/itm/Front-Wheel-Steering-Arm-Mount-Set-40mm-AC276-/230991127552?pt=UK_ToysGames_RadioControlled_JN&hash=item35c824e400


or they do a smaller one thats a bit cheaper

JT


JT

 Well the bits for the yaw mechanism are on their way ~~ 

Next thing I know nothing about......servos. I know I need one with metal gears due to the forces of moving a motor with a fast spinning propeller but that';s about it. Can anyone point me in the right direction?

DarrellW

I think..........I think I am........therefore I am.............I think!

JT

 Thanks Darrell, ordered one and decided to get some prop savers for the motors to try too. I have the collet type adaptors with the big cone on top on the quad and have so far bent 3 shafts, so these should be a bit gentler in case of motors/props meeting the ground.....

DarrellW

Quote from: JT on Sunday,June 23, 2013, 17:38:16
Thanks Darrell, ordered one and decided to get some prop savers for the motors to try too. I have the collet type adaptors with the big cone on top on the quad and have so far bent 3 shafts, so these should be a bit gentler in case of motors/props meeting the ground.....

I hate to say this but prop savers are not a good idea unless you are running your motors as pushers, it not unknown for the o rings used to hold the prop on to give way -if so crash for sure - if used as pushers then the prop is forced on not trying to lift off.
You can reduce the risk of bending the shafts by cutting them off as near to where the shaft exits the motor with a dremel (making sure that no dust gets into the motor - I mumify the motor with masking tape), be careful not to take too much off - if you measure how much bare shaft is there when the collet is on and cut the length about 2-3mm more it will be ok.
I think..........I think I am........therefore I am.............I think!

JT

 Thanks Darrell, that makes perfect sense. I have seen cable ties used instead of the bands, although that may not be a good idea either?  What do you think?
I';m not worried about damaging props, just motor shafts really if the cable ties seem to be a bad idea I will use collets and cut down the shafts as you suggest.

DarrellW

Quote from: JT on Monday,June 24, 2013, 08:15:38
Thanks Darrell, that makes perfect sense. I have seen cable ties used instead of the bands, although that may not be a good idea either?  What do you think?
I';m not worried about damaging props, just motor shafts really if the cable ties seem to be a bad idea I will use collets and cut down the shafts as you suggest.

Prop savers used for 3D profile foamies (like my Crack Yak) are very worthwhile - saves me loads of prop replacements  ::) but not the best idea for what we';re doing as I said unless being used on a Pusher setup, best way to go is to shorten the shafts or buy short shaft motors (they do exist).
With the prop savers you';ve now ordered well....
http://www.parkaero.com/twisted-hobbys-crack-yak-55-32-epp-blue-1352-p.asp
Welcome to the Fun factory  ::)  ::)  ::)
I think..........I think I am........therefore I am.............I think!

JT

 Made a little more progress with my tri :smiley:

After amxen found me someone selling the steerable gear brackets on ebay I stumbled across someone selling  two of them put together with a bit of CF rod for the same price as buying 2 individually so I ordered one :smiley: I found a small metal bar of the exact diameter of the hole thorough the centre of the rod and made the hole through my servo control horn the same size so that I could use it to exactly centre the control horn on the axis of the steering mechanism.


I used some CA glue to stick the horn in place, drilled and fixed it with some screws out of the servo packet and finally trimmed away the excess plastic with the dremel.


Next I had to take a little bit out of the rear arm to allow for the wires coming out of the servo.


The really cool thing about the servo DarrellW recommended to me was after removing the mounting lug to allow it to be placed on its side on the arm it is a perfect height for connecting to the mechanism without the need for awkward shimming! So fitting it all was a doddle :smiley:


The other two arms were much more straight forward to put the motors on.


So here it is as it is now, I';ve done all the wiring and have it all fitted ready, I will have to extend both the servo wire and ESC control wire from the back arm but then thats all the build part pretty much done. I have just got to put a FC board on and a reciever :smiley: I have ordered a crius se v2 as I know my way around multiwii and will be putting my flysky receiver on it  as I accidentally ordered a FRsky module and receiver for the quad(when no one is looking I';ll order another FRsky receiver for the tri :laugh:)


I also have 3 collet type prop adaptors on the way and will start out using 9x4.7 props as I already have a load of them!

Biffa

Excellent stuff, almost as good as my build ~~ :rolleyes:
Steve

JT

Quote from: Biffa on Wednesday,June 26, 2013, 18:06:23
Excellent stuff, almost as good as my build ~~ :rolleyes:


  :rolleyes:

  :laugh: Thanks Biffa, just want to get it flying now!!!


Biffa

Quote from: JT on Wednesday,June 26, 2013, 18:09:16
  :rolleyes:

  :laugh: Thanks Biffa, just want to get it flying now!!!


Just don';t rush and do something stupid, would be terrible to see that end up as kindling :crossfingers:
Steve

JT

Quote from: Biffa on Wednesday,June 26, 2013, 18:12:13
Just don';t rush and do something stupid, would be terrible to see that end up as kindling :crossfingers:


Rushing and doing something stupid is what I do best.......  :frantic:
No I will be gentle to start with ,I have no idea about how a tricopter behaves yet so just a bit of hovering will be the order of the day. I';ve got plenty more ply and 12x12mm dowel anyway :laugh:

JT

 The postman turned up with my final bits for the tri build today ::)

So on the crius se v2 went! For dampening I mounted it on some draught sealer stuff that I got with a shot blast cabinet, its pretty heavy duty and a double strip exactly matches the size of the little crius board, it self adheres so I stuck it to the frame and used small poundland double sided sticky pads on the board to attach it to the foam.


Here it is attached


I only needed to extend the servo wire to reach and I put the receiver up front attached with the same sticky pads.


Well that looks like a tricopter!! ::) I do need to shorten those motor shafts dramatically but other than that........... Will it fly!!!

nub

looks good, i look forward to seeing it fly :smiley:
Point and click.

Monkey see, Monkey do.

JT

 Well, I flashed the crius with multiwii 2.2 made sure everything did what it should and went into the garden filled with trepidation. It was a bit breezy but what the hell.......




I made that and it flies! I';m well chuffed. It needs PID tuning, this go was with standard settings, no oscillations but it is a bit drifty..

DarrellW

Looking really good, bet you';re over the moon  ~~  ~~  ~~
I think..........I think I am........therefore I am.............I think!

JT

Quote from: DarrellW on Friday,June 28, 2013, 13:46:50
Looking really good, bet you';re over the moon  ~~  ~~  ~~


  I am  :smiley: Thanks for your advice on the servo etc too :smiley:

DarrellW

Quote from: JT on Friday,June 28, 2013, 14:38:43
  I am  :smiley: Thanks for your advice on the servo etc too :smiley:

No problem, glad to be able to help - those servos are well regarded by most of our club members, used for anything where a good accurate servo is needed. I think you can get them from HK as well, I';ll pass on the information when I know the correct details.
I think..........I think I am........therefore I am.............I think!

JT

 Well I';ve been testing some more today in the wind, my weather station is showing up to 15mph ..... It copes very well with it and is a lot easier to handle with a bit of PID tuning done. I tried the gopro on board(in its waterproof case) and realised I was at full throttle quite a lot of the time, I removed the camera and still found full throttle needing to be used quite a bit.
Nothing was hot and on my 3s 4000mAh it flew for around 20 minutes(roughly, I didn';t time it), I need bigger props I think but how big? I had 9x4.7 props on so I';m thinking 10", my usual supplier does 10x4.5, would these be a good choice?

DarrellW

You could try them but really the best way to be sure it';s ok is to use a watt meter, if you';ve not got one then a rough guide is that it should hover just under 1/2 throttle.
I think..........I think I am........therefore I am.............I think!

JT

 It hovers at more like 3/4 throttle. I';ve ordered some 10x4.5 to try, the original rcexplorer design that used these motors used 10x4.7 props. The motors are 800Kv so should be able to take the bigger props(I think but I am a complete newbie to all this stuff).I have also ordered a couple of overlander 3s 2200mAh as they must be a fair bit lighter than my 4000mAh. This is all guesswork mind you :hmm:

JT

 Showing my newbiness here but I just got my 3s 2200mAh lipos and they are tiny!! Well compared to my one and only 4000mAh pack they are, and roughly half the weight! Hopefully this will help my underpowered issues :cool:

DarrellW

Quote from: JT on Monday,July 01, 2013, 12:38:58
Showing my newbiness here but I just got my 3s 2200mAh lipos and they are tiny!! Well compared to my one and only 4000mAh pack they are, and roughly half the weight! Hopefully this will help my underpowered issues :cool:

It has to help,  your power to weight ratio has improved no end  ~~
I think..........I think I am........therefore I am.............I think!

JT

 I will give it a try later if this pesky 17mph wind drops(the met office website says it will before dark). Still waiting for the 10" props to come though....

JT

 Good and bad Tri news.... :laugh:

The good news is the 10x4.5 props fly much better than the 9x4.7, it was still a little gutless, so I raised the max throttle signal in multiwii from 1850 to 1950, it climbs well now :smiley:

The bad news however is the vibration, I had thought with the 9" props it was probably just out of balance(they were not new) but after checking balance and fitting of the 10" the vibration was still there, after a bit of investigation I found it to be the prop adaptor  :banghead: for £2.75 each I had hoped they would be decent  :banghead:. After one flight with the 10" props fitted the bearings in the motor with the worst wobbly prop adaptor are shot :banghead: :banghead: :banghead: not good. I have tonight had to order another motor(I will sort the bearings in the knackered one but a motor gets it back in the air quicker!) and some 74p each prop adaptors with nuts instead of spinner cone thingymybobs from giant shark.
The other minor annoyance is that it has now ';stopped flying'; mid air twice, the first time I retrieved it from the field and instantly unplugged the battery, when I plugged it back in everything worked. This time I left it plugged in and armed, upon escaping the barley and making it back to open ground I tried it and the left front wouldn';t go. All the connections were fine(after all I soldered them on myself! :laugh:). After unplugging and plugging in again it miraculously worked once more..... It must be the ESC shutting down???(does that sound right????) I have another as I got 4 and will change it before the next flight....

JT

 Right new bearings arrived(they beat the new motor) wobbly prop adaptors tossed out and now it all works and flies like it should. Really controllable,climbs well, smooth and nice ::)
It weights 620g without battery or gopro but it does seem to fly better with the weight of the gopro upfront. I may even have to transfer my FPV stuff to it :smiley:

Best viewed at my house on the telly :laugh: youtube have killed the quality of one of my videos yet again :banghead: I do not live in a pixelated world!!


DarrellW

Absolutely ace! Looking spot on; looking like you';re having a lot of fun with it; well done!!!
I think..........I think I am........therefore I am.............I think!