Team MedBots

[maddox10]

You're planning to run the Bosch 400's @12V. That gives you 2 realistic options for LiPo. 3S or 4S. (5S is 18.5V, right in the ballpark for "overvolting", but then the gearratio is a tad low). A 8000mah pack will probably see you trough a fight.

This means you need 1 Imax B6 AC , cost, less than £50 delivered at your door. And that one can charge the 4S 8000mah pack from "safely flat to full" in less than 2 hours.

Pricetag together, a tad more than 1 45Ah gelcel or AGM SLA without charger.
Difference in weight..... huge. 1 kg compared to 12 kg.

[maddox10]

4 kg of CO2. That's 2000 liters of gas @1 bar @ roomtemperature. Your ram uses per stroke 27 liters. That means 60 strokes at least(not counting losses due liquid CO2 venting). In a 3 minute fight it's an action every 3 seconds (or 6 if it's double acting)

I would say, use only 1 main storage bottle if size is bothering you.

[Max]

It's 800mm long, about 900mm wide- not sure how that compares. The good thing is only the front needs heavy armouring as all the expensive parts are there, just need to protect those bottles from axes.
Losing the buffer could save some space but not very much, and by having the ram, buffer and valve inline I should get a nice flow, even with just one Burkert.
If I went for SLA I'd buy a number of 6v 10ah batteries then change them each fight, that gives me flexibility to upgrade to 18v and means I don't have a ton of weight! I feel I'd need 2 of those 8Ah lipos to stay safe with discharging, then I'd need 2 chargers as I can't charge them in parallel. I may see if a mate has one I could borrow for events, he does rc planes so should have one.

[maddox10]

I would retain the buffer, such a 1.1 kg CO2 bottle is exact the size you want for that ram.

You can do the setup with 1 Burkert, use the same setup as most feathers use. The flow is enough to satisfy your ram.

[Max]

Should have thought of that about an hour ago before I ordered 2! I meant just one burkert as an inlet, second for an outlet.
The advantage of going lipo is I won't need a voltage boaster to operate my 12v burkert, does it need overvolting?

[maddox10]

A 12V burkert? You sure that's a 5404?
But even if it's a 5404 with 12V solenoid, you want 15V+ going to that. There is a small difference between every burkert, what makes that one will work reliably @ nominal voltage, and another will want overvolting, especialy when it is warm.

[Max]

I'm unsure if I am getting a 12v or 24v coil, I thought it only came with a 24v coil but apparently not

[Max]

For my featherweight I've bought 2 3s lipos, they will be run in series. Can I make up a connector to charge them in series as well? I'd also have to make up a connector to connect the balancing plugs, does anyone know what kind of thing I'd need for this?

[webby]

Do you mean parallel? You cant charge in series haha and 2 3s in series would give you 22v

[maddox10]

Do you mean parallel? You cant charge in series haha and 2 3s in series would give you 22v

Euh, an Imax B6 charger can charge 6S LiPo. And the S stands for Series. If you hook up 2 3S packs and wire the balance leads as a 6S setup, you can charge 2 3S batteries as if it's a 6S pack.
But, I don't see the advantage. Chargers are rated in watt , and except the time to switch the packs on the leads there is no advantage in time or ease of recharging.