Paul's Goblin 700 KSE

[pvolcko]

Son of a...

Now I've got a pulse stick pack with a bad cell! Doing a very slow charge. .2C to see if I can bring it back. Sick of these battery problems.

[cml001]

New pack?

[pvolcko]

Purchased a year ago or more but been on the shelf. Opened and used to do bench work on the new goblin 700 KSE. Went to charge it up for the test flight tomorrow and one pack wouldn't recognize on my cell checker. Was down at 2.6v somehow. Rest were at 3.7-3.8v.

[pvolcko]

After this second bad experience with a stored battery pack I'm not buying spares anymore. Only what I'm actively using.

[Graham Lawrie]

Unlucky Paul, how are you going to get it back? I have tried a method of using Ni -mh for a few seconds and then normal lipo balance and that has worked

[Tony]

That's a bummer Paul, like Graham I've used the nimh setting before on charger to recover lipos. Worked for me too..

[Marius]

Catching up on the forum. That's a real nice piece of equipment you've got there. Congrats again, Paul Sorry about the cell though... Can't wait to see this monster in the air!

[pvolcko]

I used a normal balance charge on my PL8 charger. It saw and reported the low cell. I put it on 1A (for a 6s 5Ah pack) and let it trickle charge for a couple of hours until the charger got the low cell up to about even with the rest of them. Then I switched to 2.5A charge rate and charged the rest of the way up. IR on the bad cell ended up at the same place as the others so hopefully it was just a fluke and the cell is still good. I'm going to limit the test flight to 2.5min and see where the pack is at. I expect to be able to get 5+ out of the pack with hovering and light sport flying.

Weather is great here today. Got the last of the stuff buttoned up on the heli for testing. Gopro battery charged and card in it. Good to go.

[pvolcko]

It didn't crash!

Video will get posted later tonight. Maybe. My internet connection is painfully slow today. Not sure what's going on with it. Upload speed especially is pitiful. Might do a low res render and upload to get it up quickly and then upload a fullres later.

Three small issues:
1) Tail is hunting around a bit, slowly. May just need a bit higher tail gain.

2) Blade tracking is a hair off. Difficult enough getting it right with two blades...

3) There is a slight "whine" when it is spooling down. May be gear train wearing in. Maybe the OWB wearing in a bit too. I need to lube the main and tail shafts for the swash/slider. That may be what's making the noise too, dry contact with the center sphere of the swash. Everything seems pretty much freely moving so doubt it is anything binding or unlubed in terms of bearings or gears.

[cml001]

SCORE! How did the pack fair out?

[pvolcko]

The trouble pack drained normally. You'll see in the vid, I only did a 2.5 min flight just in case the pack was fubar. But they both came down in the 3.90-3.95v/cell range, so all good.

Vid is uploading now. Should get it posted here in the next hour or so.

[pvolcko]

Just finished up processing on the video now, according to the all mighty Youtube. Should be live shortly.

http://youtu.be/m5BwflXVoHg

[pvolcko]

Hmmm. not sure what's up. Did the video in 720p but it's showing max res of 360 on youtube. Hopefully just processing delays on their end.

[cml001]

Very nice!

[pvolcko]

More exciting video to come tomorrow.

[pvolcko]

Two more flights today. Playing with some gyro settings and starting to push it a bit harder.

Chris Reibert posted a comment that the whining noise is from the owb.

[pvolcko]

Yes I did record them.

[danhampson]

looks awesome Paul, does it feel much different to the stock goblin 700 with 2 blade head and tail?

[Marius]

Congrats on the maiden! That thing looks insane!

[Lee]

Looks great Paul