When I go on deployment I want to bring with me some small airplanes so I am working on this Plantraco Shoestring #16
http://www.microflight.com/Online-Catalog/ARF-Kits/MicroRacers-Kit-Shoestring-16

1s lipo 20c 100mah
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7567&Product_Name=ZIPPY_100mAh_20C_single_cell__

hexTronik 2 gram Brushless Outrunner 7700kv
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7230

TGY DP 3A 1S 1g Brushless Speed Controller
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7184

GWS EP Propeller (DD-3020 82x50mm)
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=4278&Product_Name=GWS_EP_Propeller_(DD-3020_82x50mm)_

I ordered all the parts and am waiting for the shoestring kit.  I will need to buy some silver solder so I can do the connecters.  I plan on using the ztron timer.  should have an overall weight of around 22g with a 35-40g thrust.  not sure how long the lines will be.  I will post photos as soon as I start construction.  let me know your thoughts and ideas.     

my multimeter reads 3.9 volts on these cells.  I thought all lipo's were 3.7 volts per cell?  am I mistaken?

Jeffrey,
You don't need silver solder for connectors---normal solder is just fine.

I assume your lipo's were shipped roughly at a 50% charged-up level. They really should be charged up before trying them out. Otherwise you can inadvertently overdischarge them.

Also, Jeff, better make sure the z-tron will work on one cell - this ESC has no
BEC.  (Under load, the cell will only be about 3.6 v.)

Mike A

isnt that what this is?

Low Voltage Setting: 2.8, 2.9 or 3.1v (Stop motor or reduce power 50%)

if not Ill just run it 30s at a time until i figure out the drain on the batt.

pretty sure silver solder will work.

isnt that what this is?

Low Voltage Setting: 2.8, 2.9 or 3.1v (Stop motor or reduce power 50%)

if not Ill just run it 30s at a time until i figure out the drain on the batt.

pretty sure silver solder will work.

I'm not sure what you are asking here - the Low Voltage Setting is the voltage at which the ESC will cut off the motor (or reduce it to half throttle) to avoid over-discharge of the cell.

If you are asking about  my comment on the z-tron, what I was saying was that the z-tron may need more than 3.6 volts to operate at all -- (or it may not, I don't know).  This speed controller cannot make 5 volts to run your timer circuit, because it only has a 3.6 volt supply.

Since my first post, I scrounged up the z-tron instruction sheet - it doesn't have a voltage spec. listed anywhere BUT I also scrounged up the JMP instructions and it specifically says that it will work with 2.5 to 5.5 volts -- my guess is that the z-tron uses a similar cpu and will most likely be fine on 3.6 volts.  It can't hurt to try it anyway - maybe Mike Palko would know if that spec. is available anywhere.

Mike A

There ya go - another non-issue put to bed   .   How did the soldering go?

What length lines are you thinking might work? 

I finally finished the shoestring (I have been out of town the last week.)  15' lines were too long but 10' seemed about right.  the foam that they used for the kit is a little to brittle for my taste.  I am making a new one out of 1/16" balsa.  you can see my first test flight on youtube. 
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the bellcrank got caught in the full up position.  I didnt video my other tests but the foam breaks too easily.  If you used a 1/32 plywood doubler that went 1/3 into the wing it might be fine.  also the "wheels" on the shoestring are fake so I was a bit dissapointed in that.  the bellcrank I made out of .20 plastic sheet.  pictures to follow later when i upload.

I am about 1/2 done with my balsa shoestring.  I used siff 1/16" balsa for everything except the rudder which is soft balsa.  I also used 1/32 basswood for the motormounts.  I weighed it at work today and it came in at 20 grams with everything except leadout guides, landing gear & control system.  I think that I am going to cut holes in the wing and cover it with monokote of some form to further reduce weight.  I would like the completed airplane to come in under 16-18 grams.  Pictures when I get my camera working again...

does anyone know if super thin steel wire would be lighter than spiderwire fishing line?  If so I might look into making a set of steel lines for it. 

For a 20 gram (plus l.g., controls -- so say 1 ounce) model, there should be no problems with ANY line material.  There is not going to be much line tension, no matter what.  It would be expensive but you could get the very small (I think it is about .006) 6 lb. test Spiderwire.  I can't even begin to guess at a reasonable pull test if one were trying to define it.

Mike A