Cheap and Simple ideas that work
 

In these difficult economic times I thought it might be a good idea for us to share our ideas in respect of cheap and simple things that we all could use so that we can save a few pennies. (To spend on other model products of course).

I will kick off with the following which was the subject of a thread that gave me the idea for this thread:

1) Make non return fill valves for retracts and brakes from car tyre or motor bike valves using the valve and a nipple soldered into the end. Saving per valve approx £19.00

Please feel free to post your ideas

Regards

Dennis

RE: Cheap and Simple ideas that work
 

a little physics here....torque=force x lever arm...so most of us will use a 220 oz torque servo and the thing only moves a few degrees in either direction....suggestion: use a smaller arm on say 110 oz digital servo (and maybe a longer control arm) you can calculate your actual power using the formula......and before anyone loses there minds about the safety issue..remember the weakest link...if your servo for instance put out 50 pounds of torque but your hinges will break out of thier BALSA blocks at only 20 pounds???..using this you could save hundreds in servo money [8D]

RE: Cheap and Simple ideas that work
 

Coincidentally, there was another thread recently regarding inexpensive air system components. That one was for making AIR TANKS.

[link=http://www.rcuniverse.com/forum/fb.asp?m=8303418]walmart ait tanks[/link]

Is it OK to talk sourcing and not just ideas? I don't want to dork up your thread....Send a PM to Sean and see if he will weigh in. The guy is a genius at saving $$ by finding "RC" stuff in other marketplaces before they recieve the 500% "RC" markup and packaging and that adds up to HUGE savings on the small items, just like your bike tire valve thing.

This thread [link=http://www.rcuniverse.com/forum/m_8386712/anchors_8390337/mpage_1/key_heat%252Cshield/anchor/tm.htm#8390337]heat shield blanket sources[/link] sourced, for example, ceramic heat sheild blankets at about an 80% discount to the major RC suppliers.

RE: Cheap and Simple ideas that work
 

Great idea...I found this program to help [link=http://members.cox.net/evdesign/pages/linkage_design.html]servo requirement calc[/link]

RE: Cheap and Simple ideas that work
 

Dave Rigotti posted this bit of brilliance a while back for a cheap and simple BRAKE which is effective and meets AMA regs. It could save a LOT of $$ for the guys flying lighter jets and jets off of grass where hard-core brakes are just expensive overkill.......



http://www.rcuniverse.com/forum/fb.asp?m=4350040

RE: Cheap and Simple ideas that work
 

Old method: I plugged the ECU battery in via a deans plug to a charging jack & through a double pole switch to the ECU.

New method: Fitted the plug straight to the ECU & just plug the pack in to turn it on.

Not a great money saving but I eliminated the switch, charge jack & a heap of wiring. I changed plugs to the Sermos type as they are easier to plug/unplug. - John.

RE: Cheap and Simple ideas that work
 

Here's the source for the best airline.

http://www.freelin-wade.com/fre-than...157-p-260.html

RE: Cheap and Simple ideas that work
 

Instead of spending $65 on a UAT, simply use a small $4 Dubro (or any other brand) tank with a centered pickup -
I have used this in all my jets including the 1/6 F-16 with 100 flights, and I have never had a single flameout!
KISS...

Tor

RE: Cheap and Simple ideas that work
 

Tor,

I use a 2oz. Sullivan tank (stood vertical) with the clunk centered in the tank on my Kolibri nano-turbine. Works great.

Chad

RE: Cheap and Simple ideas that work
 

Cheap and Simple ideas that work,
always show up right after i have spent lots of money on 2-3 complex schemes that don't work.

can i get an "amen"

RE: Cheap and Simple ideas that work
 

Aman Brother!!!! Ha.

RE: Cheap and Simple ideas that work
 

My hopper tanks are 4 oz Sullivan tanks standing horizontally on the narrow side, without clunk as it can move
during high G maneuvers. It simply has the pick-up tube centered inside the tank, this way it will always be in
the middle of the fuel and far away from any air - works great!

RE: Cheap and Simple ideas that work
 

Totally agree with the above . Hundreds of flights with no problems . IMO , UATs are a waste of money.....

Marc

RE: Cheap and Simple ideas that work
 

BVM and SM? hahahah I couldnt resist!

RE: Cheap and Simple ideas that work
 

Quit RC and take up hiking.... :D

RE: Cheap and Simple ideas that work
 

After my expensive electronic brake valve failed I was looking for a more reasonable alternative. I have switched to these valves and lube the wheel brakes lightly with silicone grease. Works awesome! re-lube brakes about every 30 flights or so Works just like ABS braking....14.95 vs about 100 dollars....85 dollars saved on each jet!!!


Robart 186 One-Way Air Control Valve

RE: Cheap and Simple ideas that work
 

skywritter smoke pump $89.99 and a single $15 smoke nozzle from Todd, puts out just as much smoke if not more than my buddies $200 jet smoke system. I do run a 11.7 volt lipo to the pump and he uses a 7.4v .


http://www2.gpmd.com/image/s/sulg0753.jpg

RE: Cheap and Simple ideas that work
 

Sorry, I don't understand how a clunk hurts in this app? And it seems to me that while an air trap drains nearly all of it's fuel before it sends a bubble down the line, this setup will drain less than half before causing a flameout. What am I missing here?

RE: Cheap and Simple ideas that work
 

HH,

A regular UAT is also only good for about half the tank size (dpending how far down the air trap goes.) It can't go to far down or it will flame out inverted. I don't understand the missing clunk either, but the main difference is of course, the price.

RE: Cheap and Simple ideas that work
 

I use the same setup with a pleated paper filter in the center of the 4oz tank. Gets all but about 1oz. Even with half a tank you are only looking at 2oz.

RE: Cheap and Simple ideas that work
 

Guys,

The reason it works is that the pick up is ALWAYS in the centre . A clunk compromises this and effectively just turns it into another tank ( just smaller) . Any air that is introduced into the tank will hug the outside of the tank and stay away from a centralized pickup . A clunk pickup flailing around could possibly move into the air zone . If you never burn into the air trap you can be sure that you'll never get air in the system from an unported main fuel tank clunk . People who see the sack in a UAT as a feature that will filter out air bubbles and suck to the end are missing the point that the airtrap fuel should be considered unusable . At the end of a flight I very rarely have more than a fifth of the airtrap filled with air .

As far as the filtering benefit of the UAT , I figure all the filtering that occurs before the fuel goes in the tank and before the engine is enough.

Marc

RE: Cheap and Simple ideas that work
 

Marc,
I think what they are confused about is years ago the same setup was used but there was either a sintered bronze filter or a pleated filter on the end of the brass tube, supposedly to break up any air bubbles.
As stated above, a lot of people think that the fuel in a UAT tank is usable, when in fact, the UAT fuel should never be used.
If, after a flight, you find you had to use the UAT fuel, either get a bigger main tank or shorten your flight times.
BRG,
Jon

RE: Cheap and Simple ideas that work
 

I used to make mine with the pleated filter but decided that it was overkill . The plain central pickup in a 2 or 4 oz tank ( depending on the size of the plane) has served me well for the last 5 yrs .

Marc

RE: Cheap and Simple ideas that work
 

Marc,
I assume the second tube in your tank goes to your main tank(tanks). Why even bend the tube?

RE: Cheap and Simple ideas that work
 

...to fill it up all the way.

RE: Cheap and Simple ideas that work
 

If you stand it on end, you can simply cut it off completely.

RE: Cheap and Simple ideas that work
 

OK guys, I feel like this is turning into an entirely different thread, BUT I want to say that OF COURSE I know that the fuel in the trap should be CONSIDERED unusable etc (who in their right mind wants to eat into the last TWO OUNCES or fuel? Duh! )...that is, however, no reason to deliberately MAKE IT SO. The "get a bigger tank or shorten your flight times" concept, besides falling into the "state the obvious" category completely ignores the fact that air can get into the trap for a lot of reasons, not just cus someone can't tell time. If an airleak in the system, main tank clunk problem or some other malady introduces air into a trap without a bubble-eliminating sock or clunk then the "air eating/flameout-preventing" CAPACITY will be reduced a full 50% in the configuration shown above.

Not to be disrespectful at all since I'm certain each of you has more experience than me, but since there are also a lot of very experienced folks who DO see the value of a traditional UAT type of device I remain personally unconvinced regarding this particular cost saving idea and will err on the side of caution.

RE: Cheap and Simple ideas that work
 

Instead of buying a new car, keep the old one and spend the money in a new jet.. this could also help avoid having eventual relatives borrowing your money or better yet you borrowing money from the bank! ;)

Enrique

RE: Cheap and Simple ideas that work
 

ORIGINAL: erbroens

Instead of buying a new car, keep the old one and spend the money in a new jet.. this could also help avoid having eventual relatives borrowing your money or better yet you borrowing money from the bank! ;)


Especially since you US folk just spent about $800 billion today! Ouch that's a lot of money.

Tim

RE: Cheap and Simple ideas that work
 

" besides falling into the "state the obvious" category completely ignores the fact that air can get into the trap for a lot of reasons, not just cus someone can't tell time. If an airleak in the system, main tank clunk problem or some other malady introduces air into a trap without a bubble-eliminating sock or clunk then the "air eating/flameout-preventing" CAPACITY will be reduced a full 50% in the configuration shown above.

I guess the best money-saving tip here would be to build and maintain your fuel system in such a manner that air does in fact NOT get into the trap - when I land, I never
have more that a small "drop" of air in my hopper tank, if I should ever see that there is more than that, it's about time to go over the system again. If you have a serious
air leak, no hopper tank or UAT can save you from a flame-out for more than a few seconds...

That also goes for all other systems onboard - the air system, batteries, fuel, retracts... build it and maintain it well, and you will save the entire amount that you will loose
if you don't!!:D Don't accept "a small air leak" in your retract or brake system, don't fly with batteries that are old or worn, don't fly with retracts that fail every 3 or 4 times
you test them, and you will save a lot of money!![8D]

Tor