old4570's blog View Details
Posted by old4570 | Yesterday @ 08:42 AM | 5,817 Views
Round two : Using the transmitter that came with the T720 .
A) Flight was much smoother
B) Tx is still rubbish with this model
C) S720 is way too sporty for this Tx to handle

OMP S720 with T720 Tx (7 min 48 sec)

The Dinky Toy transmitter is just not good enough for the S720 . All that dead zone at the centre of the gimbals is just too much . The Tx from the T720 was better than the one bundled with the S720 , but the flight was still complete rubbish . The S720 is just too high performance for such a Trashmitter . I am really hanging out for a 3rd party Rx so I can bind the S720 to the Taranis .

From my personal experience with the S720 , there is no way I would recommend it a a first model or a model for anyone but the experienced . The S720 demands to be BNF or PNP so that a proper hobby grade tx can be used . The garbage tx that the S720 comes with , simply will not give you the flight experience a proper tx will . I am also left wondering about the CG ?

I used a zippy 350 and , is it still a little tail heavy ? or is it just the trashmitter that is so ???? The S720 did hunt up and down and for some reason rolled right all the time . ( Same as the first flight , just not so bad on the 2nd Tx ) The trashmitter simply did not fill me with enough confidence to try out the stunt mode . ( The flight performance in the fully stabilised mode was so terrible ) . The response to gimbals input was so lacking as to be almost laughable .

The first flight , did I give a score of 5 out of 10 , well this 2nd flight simply backs up my first opinion . 5 out of 10 .
Next time I fly the S720 will be on the Taranis ..
Posted by old4570 | May 23, 2020 @ 01:08 AM | 5,897 Views
39.47 grams so far
Projected flying weight looks to be a little over 50 grams I would say at this time .
A little Porky Pig for a small DLG , maybe ok for a small slope model .
Wing came out at 20.13 grams

Not terrible for my first Printed DLG effort .
Obviously the next design will have to go on a diet !
Posted by old4570 | May 21, 2020 @ 08:17 PM | 7,431 Views
OMPHobby S720 maiden (3 min 18 sec)

Forward !

I really wanted a S720 , especially with so many crowing about it . After watching a lot of youtube video I finally got me one . I was worried about the CG location and there for I put in a zippy 350 battery to move the CG a little more forward .

Maiden Flight !

Nothing - nothing - nothing - Too Much ! That was my flight . It was beef jerky !
That Dinky Toy transmitter deserves to be hammered to death !
The S720 is a relatively high performance model being controlled by a very low performance transmitter .
For me , I simply could not fly the S720 smoothly because when I did gentle movements = Nothing happened .
So you give more stick and still nothing , then more and nothing , and then more and the model jerks rather violently in the direction you want because you are now over controlling . The trashmitter is junk ! In my humble opinion the S720 should be BNF or PNP ..
The trashmitter simply does not cut it .

Calibration !

The calibration on my S720 was a little out . There was this slight perpetual right turn .
I came home and re calibrated the model .

A) Put the model on a flat surface ,
B) Give it the attitude you want
C) Pull both sticks down and out and hold till the lights that signify calibration stop = You just re calibrated the gyro !

Final word ? ( For now )

It's been cold / rainy / wet N windy for a while now . So my location was not the best for a...Continue Reading
Posted by old4570 | May 21, 2020 @ 03:28 AM | 9,823 Views
Ok , got something achieved today in the form of some stabilisers .
Weight is now 20.13 grams , up from 17.95 grams .

Looks like ! , I won't say it , might jinx the project .

Hmmm , might just give me other ideas ...
Posted by old4570 | May 19, 2020 @ 09:03 PM | 10,258 Views

Wow , all the parts are printed and ready to rock and or stroll !
3D printed parts + 3mm Square Carbon rod = 17.95 grams .
The V911 control board is 6.04 grams ..

Is that good or is that bad ? Dont know yet !
But ready to start cutting 3mm Depron .
Can I make it lighter than a whip ? ( UMX Whipit )

Posted by old4570 | May 18, 2020 @ 06:19 PM | 4,595 Views
3D printing DLG parts (1 min 19 sec)

A quick and dirty video to show the direction I am taking .
DLG will be in the 600mm to 700mm ball park .
I want to 3D print everything but the fins and wing .
Control will be VIA the V911 flight control board .
I would have preferred the F949 flight control board , but I ran out of those ( last one is in my Micro F16 )
Posted by old4570 | May 17, 2020 @ 09:32 PM | 7,200 Views

I have been searching for the OMPHobby S720 since last year .
Everywhere I looked the price was up and with a decent to horrendous chunk of green for shipping !
So I was looking at taking a hit for wanting to scratch an itch . ( The S720 was on my must have list )

After much searching I came across Makerfire , and they had a deal ( a real deal ) on the S720 with free shipping .

The S720 is here now .

Sharp eyes might pick up on the fact I put the wheels on mine the other way round ( forward ) .
Small wheels are not great on grass so I prefer having them more forward to resist nosing over .
It's windy outside and we have some nasty winter weather on the way . So not sure when I get to take the S720 for a stroll ?

I am really impressed with the physical qualities of the S720 .
Foam , and how everything goes together .
I just need a 3rd party Rx for it now so I can bind it to my Taranis . ( Do away with the toy Tx )

Posted by old4570 | May 16, 2020 @ 06:15 PM | 7,532 Views
Is it just a pipe dream ?
My first attempt at a fuse was a failure in the worst possible way .
This is my 2nd attempt , and does appear strong enough to do the job . ( Different design )

V911 board comes in just over 6 grams
The printed fuse comes in at 7.75 grams ( Is it too heavy )
And combined around 13.76 grams ( V911 board in the fuse )

Hmmm , I dream of a 3D printed DLG !

I think I need to minimalise the fuse , still need a nose cone after all .
Posted by old4570 | May 16, 2020 @ 12:08 AM | 6,218 Views
I am still playing with the design of a all moving elevator for the UMX Whipit ( or similar built micro DLG ) using a 3mm square tail boom .

This print was R2.1 ( revision 2 in design ) . I just printed out R2.2 which hopefully addresses some printer induced errors .
Yes , the printer induces errors .
It's one thing to design something , then you have to print it and asses where the short falls are and correct them . ( Revisions )
R2.1 was close .
But corrections were needed for the way the printer lays down PLA .
Also R2 brings down the elevator height closer to default for the Whip . , as well spreading load better and being more rigid . Well , not that a whip is going to put that much load on the elevator . I think the fuse and wing take most of the load .
Fingers crossed for R2.2

R2.2 came out better and good enough to be a keeper !
Posted by old4570 | May 14, 2020 @ 11:03 PM | 7,698 Views
Leaving off from Revision 1 > https://www.rcgroups.com/forums/show...-TinkerCad-ing

There had to be some minor design changes .

Rather than two pins to make the hinge , I extended the main pin and than made a washer to go on the end .
I also increased the internal channel for the carbon tube for less hand fitting .

Viola , Revision 1.3 works ..
Washer snaps in place = Yeah !
Carbon 3mm square tube needs minimum hand fitting = Yeah !

Weight = 0.97 grams / 0.034oz /

Now back to trying to design a Pod .. / nose / canopy / fuse ... ( 1st was a huge fail )

Posted by old4570 | May 14, 2020 @ 09:18 PM | 8,097 Views

I do like DLG , especially small DLG like the UMX Whipit .
Just one problem , a serious lack of parts to play with .

This is my 2nd Mini / Micro DLG part I have designed . The first being an abject failure !
This is a all moving elevator bracket to fit a 3mm square carbon tube . ( Like on the whip )
This part is partially good and partially bad for a overall rating of average .

Thing is , the part might look good on 3D software ! But once printed out one can quickly see where the design fails in the printing process . Thankfully such small parts use very little if any PLA . I have been stress testing this part ( bending ) and it has not broken . So for a small sub 50 gram glider it should work just fine . This is a Revision 1 part and I have modified the design to R1.2 , and as I type this I have realised that more tweaks are needed and I will do a R1.3 ASAP and then print it out .
Posted by old4570 | May 14, 2020 @ 07:51 PM | 5,952 Views
JJRC H28 ( Retro quad ) (5 min 38 sec)

I haven't played with this one very much .
Simply because it cooks the battery , JJRC 1200mAh - 2s - 30C .
So this might be the 3rd time I have flown the JJRC H28 .

It handles ok , but very much like any large prop'ed - brushed - quad = Float'y and a little slow on the throttle .
Definitely needs a high discharge battery . The factory battery never cut it for the job . Hence the H28 is like new .
What was unique about the H28 was the removable arms .
You could remove the arms for transport in a back pack or something .
This was very much Pre folding arm quads .

Posted by old4570 | May 13, 2020 @ 08:48 PM | 7,934 Views
Volantex SC with 3D printed spinner (5 min 45 sec)

Cold Morning = 9.6 deg Celsius
Only a slight breeze , no sun to speak off .
Posted by old4570 | May 12, 2020 @ 06:51 AM | 6,665 Views
HQprop T5x3 5 Thrust test (1 min 9 sec)

My little 1306 could only handle 15,000 rpm .
Motor was getting hot .
Going on BG the largest motor for this style of prop is a Aokfly BS1408 .. This motor might be able to turn 20,000 with this prop . (?)

We'll find out cos I ordered the motor .

1306 - 2700kv - 3s to 4s motor
About 270 grams of thrust / 76.5watts / 15,200 rpm / 6.22Amp ( 3s )
Posted by old4570 | May 10, 2020 @ 10:53 PM | 7,688 Views
3D printed prop (2 min 39 sec)

Yeah , just had to do it !

The prop probably blows ! , but I ran a test anyways ..
Posted by old4570 | May 10, 2020 @ 01:54 AM | 7,057 Views

Available for NON Commercial purposes !!!!!

1103 etc motor mount for pusher applications .

Wings or DIY RC conversions .

Simply make a hole , and push the mount into the hole with glue . Dont get much easier than that !

Posted by old4570 | May 09, 2020 @ 10:17 PM | 7,256 Views


Another F4U @ Banggood . , I am tempted ...
But I have already spent a bundle ..
Posted by old4570 | May 09, 2020 @ 03:23 AM | 5,960 Views
R1.1 is 32mm Wide 34mm Long
R2.1 is 32mm Wide and 29mm Long

Again available free etc for NON Commercial purposes .

Last 20 + Years there has been a serious lack in smaller spinners ..
This is my Contribution . .

Next I can start thinking about a DLG Pod for 600 to 700mm span DLG's ( UMX Whipit size )
Posted by old4570 | May 08, 2020 @ 11:10 PM | 5,337 Views
32mm Universal Spinner R1 ( First Attempt ) (1 min 21 sec)

This one printed was a test print . 1 1/4 inch spinner ( 32mm rounded out to )
It's one thing to design something , and then see how it turns out / out of the printer !

STL is revision 1.1 ( Slightly revised from this first print )
The nose CAP / locking cap , was made internally longer as the first one was a little short .. Added another 5mm ( simple to make it longer = Rev 1.2 ? )

Now that I see how it looks , I will see about doing another one ...

Again available for non commercial purposes !
Posted by old4570 | May 08, 2020 @ 02:10 AM | 5,410 Views
spinner No4 (0 min 45 sec)

Looks like the 4th time is the charm .

No mods needed to fit the prop .
Also fits the Decat with a rubber band mounted prop .

Looks like my first print project worked out ok ! Yeah , it's Mikey Mouse . But it does the job .
Especially since this is my very first 3D design and print effort .
It was very much a 4 print evolution and a 7 stage design effort .
Now to move onto something else ..

Volantex Super Cub spinner .

Designed with the rubber band post/driver in place .
The nose cap and lower spinner assembly need to be drilled out to fit the shaft .
I drill the cap ( retaining cap ) to 2.5mm and then run a threading tap into it .

Not sure about printing such a fine thread (?) might be possible (?)
I have included the STL for non commercial purposes .