Rush!

Need advice.... and Thanks in advance!

Whats the best practice for airtank reservoirs for 1/8 scale models? I have the two stock airtanks for a SMF16 1/8th scale and was thinking of running the two kit air tanks in parallel for the brakes, gears and doors.

Or should i buy another, smaller tank, just for the brake system? Use the two airtanks and dedicate them to retracts and doors?

Thanks again!

Rob

bukeym

Hi

I would suggest using a separate tank always for the break system. Brake system needs less pressure to operate smoothly compared the the langing gears and doors. Of course another reason is also about safety.

CraigG

My Feedback: (40)

I always use a separate tank for brakes. Too many opportunities to loose pressure in the brake system and no reason to loose gear at the same time.

Just size your gear/door air tanks to allow at least 3 or more complete retract/extend cycles. One larger or two smaller tanks depending on what fits in your model.

Craig

Rush!

Thanks Guys... Will run separates. One tank for brakes and the other tank for gear and doors. I'll check how many cycles i can do with a one tank setup for the gear/doors.

Hopefully the stock tank will be enough for 3+ up./down cycles.

marc s

An option which seems to be also used is to hook up the brake air feed off the gear down air line , this way the brakes run off the same air system (less connectors/leaks possibly) but only work when the gear is down. Reduces the extra air tank and weight.
If you use a good failsafe device the gear should deploy if there was ever an air leak regardless.

marcs

rcjetsaok

My Feedback: (7)

I have asked myself for years why we can't maintain our pnumatic systems to help with low pressure and leak problems by tapping bleed air off the turbine????? Is it because the turbine does not produce enough pressure.. not multi-staged????? I know Someone can explain this to me...

Danno

marc s

I have heard of people pressurising smoke tanks via turbine bleed to do away with pumps but I understand the pressures are not high enough to drive these sorts of ancillaries - I guess we need and expert to chime in here.....

marcs

highhorse

My Feedback: (2)

That compressed air is pretty hot, even before the combustion happens. And I suspect that it would have it's OWN maintenence issues? PLus, of course, there would be no PSI during a deadstick situation.

rcjetsaok

My Feedback: (7)

Well all that sucks !!!!! I'm gonna build a big Cessna Citation one of these days and how am I gonna pressurize the cabin ????? All my little Disney Characters are gonna die from hypoxia !!!!!!![X(]

Danno

gooseF22

I agree with the above...I used to run two, now I just use the Down side of the gear to feed the brake valve. If the gear doesn't come down, having brakes is pointless. It makes for one fill valve. I tandem two tanks.

Some folks use the behotec valve to "turn on" the feed to the brake or use as brake valve.

causeitflies

If I remember correctly you can expect about 40 PSI from the turbine. This is what I was told my smoke tank would have to take if I used the turbine for pressure.
I too have thought about tapping the turbine for a safety in case of air loss. 40 PSI is better than none IF it can get the gear down. The gas wouldn't flow enough to get hot unless there was a major leak.

On my 1/8 SM F-16 I use the stock air tanks, one for gear/doors and one for brakes. Can't remember but I think four to six cycles easy with about 90 PSI.

Rush!

Thanks Mark,  i really didnt want to get another tank. It's getting quite busy in the cockpit area already... 

AndyAndrews

How about using one of these micro pumps? The pressure desired can be calibrated and they work in our voltage range. Pop on a festo pressure relief valve and you have a system that keeps pressure at all times.

http://www.xavitech.com/

rcjets_63

My Feedback: (4)

Those pumps have a max pressure of 450 mbar which is about 6.5 psi. No bueno! As for your suggested setup, the problem with that is the pump would always be running (venting through the relief valve) and needlessly consuming power. Should an appropriate pump come on the market, controlling it by means of a pressure activated switch would eliminate that issue.

Jim