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Drag Boat Bob
05-21-2009, 05:43 PM
No water for me today...

I was topping off my new batteries and 5 min into the charge my new Bantam BC6 started to smoke. :eek: (charging at <.5c)

After checking all connections etc. I tried the other battery. This time 3+ minutes into the charge I was again sending smoke signals. :mad:

After a lengthy call with the tech at Common Sense RC, the thing went back RMA.

I WILL get it into the water someday... :olleyes:

detox
05-21-2009, 09:11 PM
Bummer. I hope you get it fixed really soon. What prop will you be trying in your UL-1?

Drag Boat Bob
05-21-2009, 09:37 PM
Thanks Detox.

Since I have been waiting on batteries (until now), the boat has not hit the water...

However, the 1st will be the stock prop (which will most likely be uneventful, (but must record data); 2nd will be the Grim 38x55; 3rd the Grim 38x63 (both are ready).

I also have the Grim 40x57(3) and the Octura M445 (not sure which is first).

I have been paying attention to the (and your) capacitor failures. I am looking for an outlet for some Rubycon Rx30 caps. They are good to 130c instead of the usual 105c. So far no luck in a respectable voltage.

I will most likely 'bank' some low esr caps before trying the last two props.

BTW, Common Sense RC customer service was "Outstanding"!

detox
05-24-2009, 02:23 PM
Moving up from one to two 105c capacitors my capacitor temps have dropped down from 198 to 98 degrees.

Here's Rubycon's higher temp 125c capacitor:
http://www.newark.com/rubycon/25zt1000m12-5x25/capacitor-25v-1000-uf-capacitor/dp/26M6969


....

Drag Boat Bob
05-24-2009, 03:37 PM
Detox,

Great to know that the temps are cut in half when the caps are banked together.

Are you measuring the temps at the top of the cap?

A bit off topic: I have been reading miles of threads on "storing lipos". I read where you were going to use an ammo can with added muffler (for venting). Is that what you ended up with?

detox
05-24-2009, 05:52 PM
Detox,

Great to know that the temps are cut in half when the caps are banked together.

Are you measuring the temps at the top of the cap?

A bit off topic: I have been reading miles of threads on "storing lipos". I read where you were going to use an ammo can with added muffler (for venting). Is that what you ended up with?

I measured capacitor temps at the top of cap.

I store my lipos on my bedroom shelves and in my "non" vented ammo box.


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