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Posted by derk | Jun 06, 2013 @ 11:29 PM | 2,283 Views
probably one of the best ideas anyone ever had was to put LEDS on a quad copter and fly it at night!
it seems inevitable that each time i fly it outside, i get all kinds of remarks either towards me or just to the ufo-like image that they see. the fact that it is low noise and the little noise it does make sounds unlike anything else, is just the icing on top.

on my quad i installed the lights so that it is easy to orient myself and also so it resembles a flying car or similar. the last installation i made was to disassemble my 6 led headlamp and attach it so it points slightly down and right out of the center frame between the front motors. with the spotlight leds lit, it shines a very very bright well defined search beam, so to an outsider, it would look like its searching for something

so last night i was flying it around in a dark dirt lot right next to a big construction site, as a car drove by i hear a guy yell out his window "WHAT THE
@%$&??" it really made my day hearing such a reaction!

feel free to post any funny reactions you guys have of flying your multicopter or other night fliers.
Posted by derk | May 13, 2013 @ 02:05 AM | 4,888 Views
here is another butterfly model i built recently, its popped up on the forums a few times as inspiration for gliders as well as color schemes.
this one is slightly larger than average actual size at 7" span. made from eps foam as my previous ones were.

one of the aspects of these butterfly models that i love is how they fly in random patterns, turning with the slightest air currents like they have a mind of their own. in flight, they fly nearly identical to a live butterfly gliding around!

well the other day the wind was maybe 1-2mph blowing right up my local micro slope, so i went out with the wild glider and let it do its thing.
a few times it managed to stay in the lift and cruise along the hill line, and a couple times gaining height and going over the top and into the grass up top.
Rajah Brooke's Birdwing (3 min 21 sec)

Posted by derk | Nov 22, 2012 @ 12:05 AM | 3,384 Views
so, a friend of mine is coming to visit us this weekend, and she has had a really hard time recently. to help cheer her up, i thought i would make something really cool, an aluminum light saber handle

it started life as a 7.37 inch 2 inch round. after a few hours on the lathe, it was down to 1.5 inches on the handle and the "emitter" (as the other light saber enthusiasts call it) was turned down to about 1.75 inches or so. then i cut some fins and did a few nice radii and bored out the center to .88 about 1.25 deep

next was the really fun part, turning the handle into an octagon on the mill

with the part raised high enough to use the large 1.5 inch 6 flute end mill, i did a single pass .060 down from the top of the round (zero out the Z axis with the mill resting on the part)
then after that was cut, i used the flat surface at the back of the vise to give me another cut at exactly 90 degrees from the first. for the 3rd cut, you lower the mill an additional .060 to .120 so that your still only taking .060 inch and all cuts are even.
now the fun begins, to get the other 4 sides really close to the proper angles, i put the part in with the rounded uncut part up and between the vise jaws. then i used a center finder to make sure the chuck was centered on the round portion and then moved back to the flat sides.

the center finder we have uses a pivoting 90 degree angle with tick marks on it and the shank, move the table in Y until they match up. by...Continue Reading
Posted by derk | Aug 16, 2011 @ 10:25 PM | 4,695 Views
Well, posting my new tool modification

i needed to do some delicate soldering with small parts i couldnt hold, so naturally i went out and bought a "helping hands" station at radioshack. after using it for a while, i noted a need for decent lighting, and i didnt have a table lamp so thought i would take my helping hands to the next level

i dug around in my parts and found some replacement string light LEDs i had bought on clearance for $0.30 for a four pack. i also located a wall wart transformer that puts out 6.5 volts and 500ma.
so i soldered up the 4 LEDs 2 series and the 2 pairs in parallel so each is getting 3.25 volts and shines happily.
i made up a set of servo connectors so its not permanently wired.

the nice thing about these leds is they have a molded in divot so the light is cast both down and around the LED.

i know its ugly, but it's a TOOL and not a model

anyways, here are some pictures!
Posted by derk | May 16, 2011 @ 06:02 PM | 5,479 Views
I went on an off-road trail run with my dad saturday, there were 11 vehicles total, some more capable than others. it was going alright, dad had to be pulled out a couple times when he got stuck, and had to fix a few minor malfunctions on his old jeep wagoneer. we were going to go mess around in an area called "rollercoaster" its full of trails and humps, but because there was about 2 feet of snow on it, we decided to back out and go up a different trail. once they figured out where the trail is they had took last year, we headed up that way. there were some serious cut humps into the trail, dad had to be pulled through one but made it through the next one. the "main attraction" was these 2 DEEP and WIDE humps. about 4-5 rigs got through alright, a few (including dads) had to be pulled through it. it was fun to watch while one by one they got over it. it took about an hour to get them all through. then the rest of this trail was supposed to loop all the way back to the start, near where we left trailers and trucks.
the REST of that trail happened to be covered with 2-3 feet of not just snow, but thick heavy slushy snow. we slowly had the best vehicles cut trails for the rest to go through, and pulled each other when they got stuck. the worst part was when my dads tank of a jeep would start to slide down the trail towards the edge of the mountain, usually a clear long roll to the valley floor. it was extremely stressful, and even gave me flash backs to...Continue Reading
Posted by derk | May 03, 2011 @ 07:49 AM | 5,312 Views
i finally got to drive my sub with all controls functioning
its pretty quick for such a small sub, and can turn on the spot. it has to be trimmed just right or the little 4mm motor doesnt pull it down hard enough, i may have to throw a slightly larger prop on it to make up for that.

any how, here is the video of its first good run in the tub:
Micro sub-1 (1 min 2 sec)

Posted by derk | Apr 28, 2011 @ 04:56 AM | 6,013 Views
thats right, an airplane guy making a submarine?? hes got to be nuts right? well, not entirely, as we do have a pool at our apartments (not open yet) so a sub is actually a nice change of scenery for me. because of the expensive nature of underwater craft and the lack of many decent micro rtr subs, i decided to make one from things i had around here. i frequent the subs forum and always see parts similar to things i have laying around so at least they will get some use.

ok first example is one i had started a while ago but didnt progress until a few days ago. it started life as a bottle of garlic salt the bottle was just the right size (i thought when i bought it) for a micro sub. so it sat for a while until i got the itch to make a working model. i added motors, an equipment plate and a nose cone to it and even got it balanced in the tub.
but then SilentHunter posted pictures of his awesome micro sub, even smaller than mine, and i just had to take it farther

so i found another tube, this one used to hold some JB Weld putty. its 1" in diameter and has one end sealed so half the job is done right there lol
i made the nose and end cap out of sculpey polymer clay, molded to fit the tube and baked them in the oven. after baked it is fairly hard and easy to drill or cut for fittings.
after much struggling with tiny wires inside the tube, i followed SilentHunter's advise and made a tiny equipment tray to hold all the gear and even repositioned the motors to the...Continue Reading
Posted by derk | Apr 03, 2011 @ 06:09 AM | 7,769 Views
here is my latest in the line of bird like gliders, this one is somewhere between a hawk and a seagull. weight of the airframe with a 7 gram nose weight is 10.8 grams, span is 21.5 inches. it glides very well and responds great to lift, will float on an ant fart from the swale.

i am thinking of positioning the brick in the head as shown, but need to build a "camberon" control crank. it will be similar to an aileron crank but be a pull only type, a string to each camberon will pull it up and a small piece of rubber will keep tension and a stop to keep them from going down.

i will also add a balsa/plywood spar right around the CG so its not as flexible. i am thinking of gluing some white paper to the leading edges of the wings and part of the body for added strength and durability.

*edit* i got the brains installed and functioning. flight testing is still underway but here is a quick shot of the controls:
Bird glider controls.3gp (0 min 33 sec)

Posted by derk | Mar 30, 2011 @ 12:42 AM | 6,047 Views
nearly every modeler has at some point watched a bird or an insect flying so effortlessly through the sky. at times it is completely mystifying and also captivating. we all yearn to fly as they do, to be kings of the air, but are stuck on the ground with our heavy wingless bodies
so it is of coarse no surprise that these wondrous creatures get emulated in our little hobby. they come in various forms; ornithopters, slope gliders, motorized birds. but most forms do not fully emulate not just the looks but the function and control schemes that are used in nature. a link was recently posted to a video of a fellow modeler in Japan who studied gliding birds and tried to copy the way they control their wings and tail for direction. i think he got it DARN CLOSE, his models have absolutely no vertical surfaces just as the birds do and yet fly with a good amount of stability.
so it is now a personal mission of mine to build my own flyable bird in the same manner, and what i am posting here is the beginning of just that and my experiments so far.

the Black Vulture and Rough Legged Hawk weigh 1.5 grams and the butterfly weighs 0.5 grams. i got them to fly, but had trouble getting them to go where i wanted them to, usually they had a slight left turn. i tried using a mix of ailerons and flaps and tail trim, but it usually still wanted to turn left... so i emailed KOUBOU, and he replied with the answer the next day.
apparently in his research and testing, he found that using the...Continue Reading
Posted by derk | Feb 28, 2011 @ 08:29 PM | 6,597 Views
I was cleaning today and came across some of my old paper models. they are all VERY small 1 inch or less generally, printed from the computer and glued together.
some of them are parts of real aircraft cobbled into original creations.
among them is a few pieces of origami i folded from tissue paper. i used tissue as normal paper doesnt scale down this far and becomes too thick....Continue Reading
Posted by derk | Feb 01, 2011 @ 12:49 AM | 6,228 Views
So with a recent magnet order from k&j magnetics, I bought some pyrolitic graphite and cube magnets.
For those who haven't seen it, pyrolitic graphite is diamagnetic or repells a magnetic field and if said field is strong enough, can be lifted against gravity and even carry a very small weight.
So I cut it into small "levitatable" pieces and carved some futuristic looking vehicles. I plan on getting more magnets to make a full track or maybe a road layout similar to a mini train set

The vehicles are depron and eps foam with marker details.
The car and suv are about 0.5 inches while the semi is 1.25 inches.
This would make an excellent school project for a science fair or class report.
Posted by derk | Nov 22, 2010 @ 06:27 AM | 6,942 Views
well guys saturday night at around 8 p.m. the local hobby shop caught fire. it burned it and 2 other businesses down with it. they may not have been the best shop, but it was still the one nearest my house and only about 4 blocks away. i am not sure if they will build a new one or not, but its still a large loss for the area.
this is not my video but it shows the shop going up
Performance RC Hobby Shop Fire Burns to the Ground (8 min 30 sec)


http://www.spokesman.com/stories/201...da-businesses/

well, at least there are about 4 others all within a 45 minute drive
Posted by derk | Nov 18, 2010 @ 11:20 AM | 7,022 Views
wow first snow of the season and while sitting here browsing, an accident right outside! looks like everyones alright but they still sent 2 firetrucks. happened at a 4 way stop, apparently one didn't lol

anyhow, good to see some snow finally. now i can think about my other hobby; snowboarding
Posted by derk | Oct 25, 2010 @ 04:54 PM | 6,210 Views
i read this quote while researching for my tesla coil: I do not think there is any thrill that can go through the human heart like that felt by the inventor as he sees some creation of the brain unfolding to success... Such emotions make a man forget food, sleep, friends, love, everything. (Nikola Tesla)

i think that most all modelers can attest to how true this is, when you finally finish that new plane, its just so exhilarating to see that creation work. you really do forget everything else that could be going on, its just you and your machine.

this is why we need to help the next generation learn to be builders and makers. it really is an artform to make something from the ground up and then see it work.
Posted by derk | Jul 24, 2010 @ 05:03 AM | 7,803 Views
so when i was a kid, i was always fascinated by anything that looked like it came from a science center. things like cloud chambers and fog tornadoes, tesla coils, van de graf generators, you know what i mean. my childhood idol was Bill Nye (still like him too) and i watched his show everyday after school.
there was always this one lamp that i saw in the mall and begged my parents to buy for me but never got, it was the Rocket Tornado Lamp. they eventually stopped showing up in stores so the chance and thought to get one passed.
so not too long ago, i decided it was finally time to make one for myself, but with a twist, instead of little pellets, i'd make one like in the 2 soda bottles but continuous!

i hunted around for ages trying to find the right shape for the body, it had to be tubular about 10 inches high, clear, and NOT glass. it took about 2 months of scrutiny of anything i saw at the store, "is it plastic? would those pieces come out?" or this ones not big enough, its too wide, its too flimsy.

until finally, i found a neat little item that was absolutely perfect for what i needed. it was a straw holder complete with 50 straws at Target for 4.99! roughly 9 inches tall, and 3.25 in diameter, it is exactly what i had been searching for. with a wall thickness about 3/32 of an inch, it wasnt too flimsy like some packaging i had looked at.

so then came the task of gathering the various other components to make this all work. i needed pipe, flexible...Continue Reading
Posted by derk | Mar 21, 2009 @ 04:55 PM | 7,638 Views
i have been looking and watching in the sloping forums for anyone flying true scale modern jets like f-15, f-35, anything newer like this. all i have seen is people ask about it (myself included) and being told that "they dont fly good as a sloper" "they need 30mph wind to fly at all" or just to avoid them at all.
it is my belief that if built light enough, they would perform fine with just a few odd differences vs a "normal" sloper. all the ones i have seen done, were rather heavy hence the 30mph wind requirement and alleged lathargic handling. if i built one, i would shoot for a 25-30" ws and under 25 oz. i think that if kept light and streamlined, it would work in both light wind and heavy wind and be a decent performing plane.

now i know that people will tell me all kinds of things about this, but its what i want to try out for myself because i have not seen it done how i am talking about. if i am right, it will be a fun and origonal plane as far as sloping goes.
if it doesnt, i can always slap on an outrunner and take it to the park

one thing i can say, is i have built a number of powered jets; park fliers, micro fliers and small chuck gliders. all of them will glide so long as they are not a heavy and fast affair.

so in closing, to all those who thought about trying a pss jet and heard it doesnt work or isnt a good performer, watch this blog because i will post results of my own findings.