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Old Jan 07, 2013, 11:00 AM
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United States, TX, Austin
Joined Dec 2012
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Holy Dan!

That sounds like a close call! I'm glad you weren't injured, and I'm sure you have learned to be more careful around those Lithium bombs that you're using! Another thing to be careful of is not putting a battery in a box with a bunch of other gear like pliers, etc. Imagine if your screwdriver shorted out your battery when it's sitting in the passenger seat as you drive out to the field

Regarding battery damage, I'm no LiPo expert but a dead short like that would cause current (Amps) to rise until the ESR of the battery was met. At some point, even these batteries can only deliver so much current at once. Since the connection was broken so quickly (due to vaporizing wire) my gut feeling would be that they are fine. But maybe charge them on a stone cutting board or something

Interesting ideas about different wing shapes... I should be working now so I hope to post about that later!
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Old Jan 07, 2013, 11:21 AM
Romans 8:34-39
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United States, FL, Davenport
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Get the lipos out of the house, NOW, if you haven't done so already. They can catch fire even days later. They're very dangerous once damaged and metal fires are difficult to deal with. They're cheap enough not to take any chances with. And, when you do decide to replace the connectors or standardize on one (I use xt60 myself) do yourself a favor. Cut the positive side of the connector off, put on shrink tube, solder on the positive terminal of the new connector, shrink tube it, then do the negative side. Or vice versa on the + / -. DO NOT CUT BOTH WIRES AT THE SAME TIME. You can short the battery with the wire cutters! Never having more than one lead exposed at a time while soldering makes it much more likely you won't short out the battery.
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Old Jan 08, 2013, 01:29 AM
Hot glue held together by foam
United States, WA, Vancouver
Joined Aug 2010
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Hey Dan , it says on your blog page that you like rocketry , so I thought you might be interested in this video

Flite Test - ROCKET PLANE (7 min 47 sec)


Al
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Old Jan 08, 2013, 09:31 PM
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United States, TX, Austin
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OK Dan, I've got a story for you!

Lately the weather has been cold and windy, but we occasionally get a calm day and I've usually been itching to fly again by the time it comes.

On Saturday, while it was still windy, I decided to ride my bike around the neighborhood and see if any good flying spots appeared. My current spot is a bit far away and not the best place. Lo and behold, I found a huge piece of state property nearby. It was big, open and had a slope and a view of downtown...nice! There were a few signs about it not being a dog park, although there were many people with dogs running around in one area. It turned out to be some state business like a sign making shop, but being the weekend no one was working.

On Sunday, the wind died down so I charged up the Lipo and headed to my new field! And it was awesome! It was a nice big area with no people and plenty of room. The grassy area was in an L shape and I was standing in the corner of that L, getting maximum use of the flying area

After a while, I decide to take the plane way up high and far and am having fun when suddenly the motor quits and it stops responding to my controls!!! UHOH, I think, it must have gone out of range!!!

The plane was headed back towards me at the time, so before the panic could truly set in, the motor started up again and the plane was back in my control. ! Scary. Who knows how far it would have glided if I had lost it at that altitude (maybe 200-300 feet?) but it would have been in houses for sure...

Anyway, I decided to keep it closer in after that and start researching better receivers than my HK $8 cheapie.

Fast forward to Monday... I work from home, so if there's a nice day it's not really a problem for me to duck out for an hour to go fly. Yes, I know

I head back to that same field, but this time it is full of state vehicles, pickups and big trucks. I wonder if I should really be flying here, but the field is really huge and quite wild, so I decide it's better to beg forgiveness this time

But, I parked in a different place this time, closer to some trees <cue ominous music>.

Feeling confident, I decided that I'd try strapping my point and shoot camera to the plane like I have done once before. It's pretty janky but doesn't seem to affect the flight at all. So I chuck the plane into the air and I'm flying around, showing off because I know the camera is recording... I like flying toward myself and trying to catch myself in the frame you know, so I'm doing that when all of the sudden WHERE DID THAT TREE COME FROM THAT IS NOW RIGHT IN FRONT OF THE PLANE???

and then CRRRRRrrrrrrashhhhh..... Camera falls out and lands with a bounce...ouch! But the plane is still in the tree!!!

hmm, ok well it's just barely hanging there, maybe the wind will blow it down. <waits> no, not coming down, hmm...

Well, I could go home and get a ladder, but what if the wind knocks it down before I get back? Maybe I'll just try to knock it out of the tree with something.

<rummages through car and finds empty water bottle>...perfect!

<throws it in an arc so that it just barely touches plane>....nothing happens.

<tries again>...nothing...<again>...nothing...

<goes back to car and gets a shoe>... <throws shoe at plane in tree> ... it moved!

A few more taps with the shoe and suddenly! The plane pivots to face nose down and then plummets in a low drag fashion from about 12 feet high down to the ground nose first One wing snaps off and the nose is crunched,

By now I am sure that the entire Texas State Sign Commission is watching and laughing from their offices, so I try to gather my things and quickly leave. I get the plane and the bottle and radio into the car and...hey, where's the shoe?

I look here, there, everywhere and then (forehead slap) I look in the tree. Sure enough, my shoe is hanging in the same branches that ate my plane moments ago

I briefly go get the other shoe from the car and make a few halfhearted attempts at retrieving shoe one, but stop before I end up with two shoes in a tree

Now, this pair of shoes is worn out and basically ready for the trash already, and by this point I imagine ALL of the state employees are standing by the windows watching and laughing, so I pack up my shoe that is not in the tree and get out of there.

Cheers
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Old Jan 08, 2013, 10:01 PM
Hot glue held together by foam
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Datura , was that your Bixler or your SUE ?
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Old Jan 08, 2013, 10:40 PM
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Originally Posted by balsa or carbon View Post
Datura , was that your Bixler or your SUE ?
It was the Bixler! I am especially glad I have a SUE now though, as I can still fly while I am repairing the Bix

I do still want to make another scratchie, I'm just feeling a little overwhelmed at all of the things I could be doing... I've got an ArduPilot sitting here that's never been in the air, I want to get a better flight camera, I want to figure out how to program elevons for my existing SUE in my TX, etc. etc...

I am discovering that I do like to fly aerobatics, loops and rolls and stuff, so a scratchie that was more aerobatic does sound appealing. I have a feeling that with the right dimensions, the same cheap motor+esc on a foam core plane could blow the socks off of my stock Bixler.
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Old Jan 08, 2013, 11:56 PM
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It was the Bixler! I am especially glad I have a SUE now though, as I can still fly while I am repairing the Bix
I know how you feel. My Hawk Sky is sitting in the Ad Astra repair facility (kitchen) until I feel confident enough to take the poor thing out and give it another bea... beautiful flight... (you thought I was going to say beating, dincha?).

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I do still want to make another scratchie, I'm just feeling a little overwhelmed at all of the things I could be doing... I've got an ArduPilot sitting here that's never been in the air, I want to get a better flight camera, I want to figure out how to program elevons for my existing SUE in my TX, etc. etc...
I know how you feel. I don't have the ArduPilot (yet), but I have identified a few pieces of unused equipment in my business that I'll sell through eBay to afford those toys... ArduPilot, FPV, FatShark glasses, etc...

Mind you, it is probably a good idea for me to learn to fly, first.


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I am discovering that I do like to fly aerobatics, loops and rolls and stuff, so a scratchie that was more aerobatic does sound appealing. I have a feeling that with the right dimensions, the same cheap motor+esc on a foam core plane could blow the socks off of my stock Bixler.
I KNOW how you feel. I was working on a HEMI SUE tonight dreaming of SEMI SUE and MEGA SUE and ... dare I say it ... NON SUEs.... Everything was going well until I picked up the Locktite Spray Adhesive (Safe For Foam) and sprayed the KF2 spar... pressed it onto the wing... and watched it turn into abstract art as the solvent ate the foam up.

Tomorrow I'll go back to Office Depot and get my money back for the spray. "Safe for Foam" my furry grey posterior !!!

However, I've been looking at a lot of flying wings... One is the Pribos from Europe http://rc-soar.com/pibros/

Another is the Raptor, made by a couple of fun nerdy kids who call their video blog "My Geek Show". The first in a series of about 8 planning, build, fly, and crash videos is
Episode 52 - Announcing the Raptor! (6 min 45 sec)
The thing that impresses me about the Raptor is that it's based on a foamy from Black Sheep that is very rugged... "fly it into brick walls and it's still okay" rugged. If you go to the original Black Sheep website (the Youtube has references to it), you can see their complete build video and see how they robustify their foamy to make it so durable. The raptor is ultra acrobatic, by the way.

Of course, it would help if I could learn to fly.

Ad Astra... if I could learn to fly...
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Old Jan 09, 2013, 11:49 PM
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Get the lipos out of the house, NOW, if you haven't done so already. They can catch fire even days later. They're very dangerous once damaged and metal fires are difficult to deal with.
Already done. I have all my "questionable batteries" in individual plastic bags in the all-metal BBQ out in the yard. I just hope that you aren't going to tell me that temperatures below freezing are also bad. Of course, if they do catch fire I'm going to have to seriously clean the grill, or risk dosing eveyrbody with lithium salts. Nobody would be depressed anymore...

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Originally Posted by bhoov128 View Post
And, when you do decide to replace the connectors or standardize on one (I use xt60 myself) do yourself a favor. Cut the positive side of the connector off, put on shrink tube, solder on the positive terminal of the new connector, shrink tube it, then do the negative side. Or vice versa on the + / -. DO NOT CUT BOTH WIRES AT THE SAME TIME. You can short the battery with the wire cutters! Never having more than one lead exposed at a time while soldering makes it much more likely you won't short out the battery.
I'm a volunteer firefighter. Every now and then we have to cut the service wires going into a house. We have a nice long cutters on an insulating pole to do this... and of course the rule is "DO NOT CUT THE WIRES AT THE SAME TIME"

Years ago the then-Chief gave a rookie the assignment of cutting the service wires. He grabbed the pole and hustled off around the side of the house. A minute or so later there was a loud explosion, a bright flash, and a loud yell. He had reached up and cut all three lines at once. Fortunately he was okay. The cutters on the pole were not. There was a hole the size of a quarter missing from one of the shear blades... and the other shear blade was simply gone..

His name was "Sparky" for the next year or two. Nope - it wasn't me. Not to say I didn't do dumb things... But this one I managed to miss.

Ad Astra, with sparks !!!!
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Old Jan 09, 2013, 11:53 PM
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OK Dan, I've got a story for you!
... and it is a good one !!!!

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I briefly go get the other shoe from the car and make a few halfhearted attempts at retrieving shoe one, but stop before I end up with two shoes in a tree
Cheers
So... why would having two shoes in a tree be much worse than having one shoe in a tree? Well, yeah, there is the embarrassment of being seen trying to recover it... but unless you have a one legged friend, one shoe is pretty useless.

Ad Astra, but not with bare feet.

Dan
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Old Jan 10, 2013, 12:10 AM
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I'm building a 1m wingspan biplane out of Depron. The closest thing I can describe it to would be the foam trays you get meat in at the grocery store.
Hmmmm.... foam trays for meat...

That got me to thinking... what about using the flat part of a big meat tray? A little work with a search engine turns up a 14 3/16" by 18 3/16" foam tray ... which would have a clear flat center of about 12.5 to 13" by 16 to 16.5" ??? Turns out those are relatively cheap. Cost - $36/100

http://www.webstaurantstore.com/genp...0%20WHITE.html

And this is a link to the original manufacture's full line. http://www.genpak.com/product/standa...rmarket-trays/

Does anybody else see the wings of a plane in there? you can probably get a 32" wide model pretty easily... and cheap. I see a biplane myself. I like my Uberlite biplane. I want more biplane in my life.

I also like cheap. The Missus doesn't ask so many pointed questions if I can do things on the cheap.

Those food trays might be a bit more rugged than 'de-paper-ed' DTFB. On the other hand, the DTFB is much bigger than the clear center of a meat tray. Hmmm... life is always compromises.

Think I'll visit the butcher with a strange request the next time I'm in town.

Ad Astra, on wings made of food trays?

Dan
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Old Jan 10, 2013, 10:01 AM
Romans 8:34-39
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United States, FL, Davenport
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Originally Posted by Ad_Astra View Post
Hmmmm.... foam trays for meat...

That got me to thinking... what about using the flat part of a big meat tray? A little work with a search engine turns up a 14 3/16" by 18 3/16" foam tray ... which would have a clear flat center of about 12.5 to 13" by 16 to 16.5" ??? Turns out those are relatively cheap. Cost - $36/100

http://www.webstaurantstore.com/genp...0%20WHITE.html

And this is a link to the original manufacture's full line. http://www.genpak.com/product/standa...rmarket-trays/

Does anybody else see the wings of a plane in there? you can probably get a 32" wide model pretty easily... and cheap. I see a biplane myself. I like my Uberlite biplane. I want more biplane in my life.

I also like cheap. The Missus doesn't ask so many pointed questions if I can do things on the cheap.

Those food trays might be a bit more rugged than 'de-paper-ed' DTFB. On the other hand, the DTFB is much bigger than the clear center of a meat tray. Hmmm... life is always compromises.

Think I'll visit the butcher with a strange request the next time I'm in town.

Ad Astra, on wings made of food trays?

Dan
Well in that case, here ya go.
http://www.rcgroups.com/forums/showthread.php?t=1672929

Instead of just using the flat part for wings, I used the rolled edge for undercambered wings.
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Old Jan 10, 2013, 10:11 AM
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nice use of materials!
did you ever manage to maiden that 'Garbage plane' ? (YOUR words... it looks nice! )
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Old Jan 10, 2013, 12:27 PM
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nice use of materials!
did you ever manage to maiden that 'Garbage plane' ? (YOUR words... it looks nice! )
YEAH... Inquiring minds want to know. I want to know too.



Ad Astra per garbage

Dan
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Old Jan 10, 2013, 01:01 PM
Romans 8:34-39
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Nope I have never maidened it. I knew with my flying skills I would destroy it immediately and something about creating the whole thing without plans from the ground up made me attached to my trash pile.

Now that I am comfortable flying I think I'm actually going to maiden it, perhaps I'll shoot for this weekend. I'll need a videographer - my 7 yr old daughter tried to video my UM Spitfire last week and I got lots of shaking, lots of narration, some singing, and very loud gum-chewing. Not much Spitfire though.
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Old Jan 10, 2013, 02:04 PM
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I'll need a videographer - my 7 yr old daughter tried to video my UM Spitfire last week and I got lots of shaking, lots of narration, some singing, and very loud gum-chewing. Not much Spitfire though.


I got one of these $20 Turnigy video cams from HK. It's actually pretty good quality ! I've attached it to the hat band of a ball cap worn backwards. The Missus thinks it looks Very Stupid Indeed. The big problem is that it can shift around a bit I don't where it is actually pointing. I've gotten home and found videos that contain a lot of shaking, lots of narration, some wheezing but not much plane. So I've gotten out an old hard hat and I'll be firmly attaching it to the rigid bill. That way I'll not only improve my aim, but I'll also be improving safety !!! I'm just trying to figure if I want to attach a stick and viewing frame so that I'll be really annoy... know where the camera is pointing.

Ad Astra, although our daughters will keep our hearts on Earth with them

Dan
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