Search found 23 matches

by AC5ME
Sep 01 2022 10:13am
Forum: Motor Technology
Topic: MGM-Compro controllers?
Replies: 0
Views: 139

MGM-Compro controllers?

I've been successfully using a MGM HBC280120-3EI controller for a couple of years now, although there's been plenty of grief. It's in a (yet to fly) aircraft running 115V at 250A. Does anyone else have some experience to share? The documentation is good, but has some errors and omissions and leaves ...
by AC5ME
Sep 01 2022 9:49am
Forum: Items for Sale - Used
Topic: MGM-Compro display
Replies: 0
Views: 172

MGM-Compro display

Like new condition, with bezel. 5V power supply. Used briefly for a development project, works as advertised for the HBC280120-3EI with "RxD / TxD (RS 232 TTL) galvanicaly isolated". $550 new, I'd take $250 OBO.
by AC5ME
Aug 31 2022 12:08pm
Forum: Electric Aircraft
Topic: Self-launching sailplane conversion
Replies: 27
Views: 2798

Re: Self-launching sailplane conversion

The electronic braking provides about 15lbs of force measured tangent to the rotor, I'm hoping this will be sufficient to prevent windmilling but I don't know until I do some flight testing. I have a mirror in the cockpit to verify the prop is vertical, I hope I can rotate the motor slowly enough to...
by AC5ME
Aug 31 2022 10:16am
Forum: Electric Aircraft
Topic: Self-launching sailplane conversion
Replies: 27
Views: 2798

Re: Self-launching sailplane conversion

I though an update might be of interest. I've made the first taxi test recently, and all is well so far. I'm hoping for first flight next week, depending on how the ground testing moves along. I'd be grateful for any input from the members here, as I've yet to have my design vetted in-person. Except...
by AC5ME
Jan 28 2021 12:44pm
Forum: Battery Technology
Topic: Li-ion Wholesale?
Replies: 3
Views: 386

Li-ion Wholesale?

https://liionwholesale.com

Anybody care to share their experience with this company?

Thanks!
by AC5ME
Jan 21 2021 8:50pm
Forum: Battery Technology
Topic: kWeld - "Next level" DIY battery spot welder
Replies: 1549
Views: 253818

Re: kWeld - "Next level" DIY battery spot welder

It's not making any tones at all, and it would be nice if it did.

Thanks.
by AC5ME
Jan 21 2021 6:05pm
Forum: Battery Technology
Topic: kWeld - "Next level" DIY battery spot welder
Replies: 1549
Views: 253818

Re: kWeld - "Next level" DIY battery spot welder

I've been having fun welding bits of metal together with my new Kweld but it's not beeping at me as described in the manual. Is this something I can fix?

Thanks!
by AC5ME
Jan 14 2021 7:30pm
Forum: Battery Technology
Topic: Battery Design advice sought
Replies: 22
Views: 1600

Re: Battery Design advice sought

What type of BMS did you go with?
by AC5ME
Jan 14 2021 7:28pm
Forum: Battery Technology
Topic: Design help?
Replies: 17
Views: 1157

Re: Design help?

Thanks for that John, but I've written off Lipo for a number of reasons. I'm pretty much locked in to the 18650 format.
by AC5ME
Jan 14 2021 1:42pm
Forum: Battery Technology
Topic: Design help?
Replies: 17
Views: 1157

Re: Design help?

My design goal at this point is for 250A max for no more than 2-3 minutes so 12.5A per cell, which I believe is longer than what's considered a "burst"?

The 3500mA LG MJ1 is appealing but at 10A max continuous, I'm guessing it would be over-stressed.

Thanks.
by AC5ME
Jan 11 2021 2:40pm
Forum: Battery Technology
Topic: Design help?
Replies: 17
Views: 1157

Re: Design help?

Any advice on tools for selecting the best 18650 for my application? I found this spreadsheet which seems like the best thing going so far:
Cell comparison spreadsheet.xlsm
(414.33 KiB) Downloaded 51 times
Any suggestions on US-based suppliers as well?

Thanks!
by AC5ME
Jan 10 2021 3:04pm
Forum: Battery Technology
Topic: Design help?
Replies: 17
Views: 1157

Re: Design help?

Thanks for that Mr. Sanchez, it looks very similar to what I'm planning and well done. I've yet to find a suitable copper bus like that since I'm using the "diagonal" style holders due to space constraints, do you have a good source?
by AC5ME
Jan 10 2021 1:25pm
Forum: Battery Technology
Topic: Design help?
Replies: 17
Views: 1157

Re: Design help?

Good video, thanks for that. Now I've got another YouTube rabbit hole to go down. I'm guessing he had to solder the copper because it's difficult to spot weld but I'm going to try not to after watching this: https://youtu.be/byvr-dwwao4 According to the chart it seems like one wide strip of nickel w...
by AC5ME
Jan 08 2021 7:10pm
Forum: Battery Technology
Topic: Design help?
Replies: 17
Views: 1157

Re: Design help?

This is just what I was looking for, thanks! I like the one wide strip idea, according to this chart my 2P strip won't cut it. Ampacity chart.jpg Then maybe a long strip of copper connected to each cell as a bus down the side? Since you've been kind enough to help me out, I've got another one: If I ...
by AC5ME
Jan 07 2021 7:29pm
Forum: Battery Technology
Topic: Design help?
Replies: 17
Views: 1157

Design help?

Hi all, I'm a first time battery builder and was hoping someone who knows more than me (everybody) would like to comment on my design. It's a 28S20P 18650 split into 2 separate packs wired in serial to provide 115V. There's 280 cells (14S20P) folded like a taco in a 10X9X6 inch package times two. I'...
by AC5ME
Oct 31 2020 1:42pm
Forum: Electric Aircraft
Topic: Self-launching sailplane conversion
Replies: 27
Views: 2798

Re: Self-launching sailplane conversion

Thanks John, that's exactly the kind of input that I'm looking for and I've heard rumors elsewhere along the same lines. I'm not an engineer so a lot of this stuff escapes me but I'm learning a lot as I go. I'd really like to find something US built but I know that's a long shot. Any suggestions? I'...
by AC5ME
Oct 30 2020 10:51am
Forum: Electric Aircraft
Topic: Self-launching sailplane conversion
Replies: 27
Views: 2798

Re: Self-launching sailplane conversion

I contacted Zero about that possibility and they said they'd like to help me except the lawyers won't let them... I'd like to avoid using anything "wrecked", and since there are affordable new components available I have the luxury of selecting something that's just right. It sounds like I...
by AC5ME
Oct 26 2020 10:41am
Forum: Electric Aircraft
Topic: Self-launching sailplane conversion
Replies: 27
Views: 2798

Re: Self-launching sailplane conversion

I've considered re-mounting the engine, there are a number of issues though. The main problem is that no matter the thrust number I come up with through testing, I don't have any real data to show what kind of performance this would produce because nothing's been published in the manuals. I've done ...
by AC5ME
Oct 25 2020 2:56pm
Forum: Electric Aircraft
Topic: Self-launching sailplane conversion
Replies: 27
Views: 2798

Re: Self-launching sailplane conversion

It's a shame Windward Performance quit making this line of gliders, very innovative and made right here in the US of A. They were pursuing a self-launcher years ago based on this airframe, but they're not even answering the phone these days. I considered buying one but it would have been a big job t...
by AC5ME
Oct 24 2020 2:37pm
Forum: Electric Aircraft
Topic: Self-launching sailplane conversion
Replies: 27
Views: 2798

Re: Self-launching sailplane conversion

Any opinions on Neumotor 120xx, APD UHV 28S controllers and the batteries that Neumotors supply? It looks like they may have most of what I need. I'm thinking 28S5P, for around 100V and 250A. 25Kw max output and around 150lb of thrust as a preliminary goal.

Thanks!
by AC5ME
Oct 21 2020 7:02pm
Forum: Electric Aircraft
Topic: Self-launching sailplane conversion
Replies: 27
Views: 2798

Re: Self-launching sailplane conversion

I never ran the motor, and it's already removed. Long story... Are you aware of any online calculators to help determine this?
by AC5ME
Oct 21 2020 9:01am
Forum: Electric Aircraft
Topic: Self-launching sailplane conversion
Replies: 27
Views: 2798

Re: Self-launching sailplane conversion

That's a good tip, it's very close to what I'm doing. Thanks helno. One area where I'm flailing is how to calculate the thrust required for my application. I'm guessing around 100-150 pounds to get at least 500fpm. This number will drive the rest of the design, so I'd like to get it right and I'm ha...
by AC5ME
Oct 19 2020 12:14pm
Forum: Electric Aircraft
Topic: Self-launching sailplane conversion
Replies: 27
Views: 2798

Self-launching sailplane conversion

Hello everyone. I came came across this forum recently while I was researching options for my project. I’m hoping some of you would share your thoughts with me on my conversion. I’ve got a Russian Aviastroitel AC-5M glider with a 25-ish HP 2-stroke. On a cool day at sea level it might do 500 FPM, I’...