How much do you wind a rubber motor?

supercruiser · Post by **supercruiser** » Fri Mar 25, 2011 9:17 pm

The answer is: it depends.

Depends on size of the rubber band, condition, and the rubber qualities.
Which can vary from batch to batch. The rubber is not consistent in quality
even with the same size and manufacturer.

So what to do? Again, I recommend Don Ross' book on rubber powered models. There is a chart that gives an idea of how much to wind a rubber motor. But, it's not guaranteed.

You can always buy some rubber and test how many winds until it breaks.
Then when you put a rubber motor in your model; go about 90% of turns it took to break it.
Pre-stretching or "breaking in" the rubber has a great affect on how much you can wind it. Cleaning and lubing also has a big affect.

Just as a rough idea..... for 3/32" width rubber you can wind 100 turns for every inch of relaxed length.( the rubber must be cleaned, lubed, and pre-broken in)
For example: If your rubber loop is 15 inches long, you can stretch-wind 1500 turns, with FAI tan II rubber. (100x15=1500)This isnot the rubber supplied in the kits.

The rubber supplied in most of the Guillow kits can only be wound 75 to 125 turns. Thats all. After a couple of flights, throw the rubber away. It will break easily.

ADW 123 · Post by **ADW 123** » Fri Mar 25, 2011 9:26 pm

Thanks again

Supercubber95 · Post by **Supercubber95** » Sat Mar 26, 2011 9:24 am

Rubber is something I'm not good at. I'm flying a Cessna 180, a Super Cub 95, (the 600 series one) and a 900 series Mustang. They all fly fine but run out of power too soon. I'm flying with "Super Sport" 1/8" 1.5 times the length of the plane, doubled back. Is my problem too small of rubber? I wind it 200-250 turns. Lubed with Armorall. Thanks.

Phugoid · Post by **Phugoid** » Sat Mar 26, 2011 9:49 am

you can tripple the amount of winds you are using without even pushing it too hard........

Supercubber95 · Post by **Supercubber95** » Sat Mar 26, 2011 1:17 pm

Okay... Next question: How long can I use one piece of rubber if I wind it that much?

Phugoid · Post by **Phugoid** » Sat Mar 26, 2011 2:29 pm

As long as you like, just keep it clean and inspect it for knicks and cuts and leave it to "rest" for a bit. It's weird, I know but it seems to recover when left for a bit. I have a piece that I use with my favourite FROG model, it must have made 50 or so flights but it still keeps on going.

If I use castor oil as lube I wash it out after a flight session, dry it with a tea towel, then leave it to dry in air before sealing it in a bag before keeping it somewhere dark (an old biscuit tin).

ADW 123 · Post by **ADW 123** » Sat Mar 26, 2011 2:31 pm

how would you suggest getting the rubber band in and out of my arrow quickly and easily?

Phugoid · Post by **Phugoid** » Sat Mar 26, 2011 2:47 pm

a stuffing stick.

ADW 123 · Post by **ADW 123** » Sat Mar 26, 2011 3:06 pm

thing is, the fuse for the arrow is very long

Supercubber95 · Post by **Supercubber95** » Sat Mar 26, 2011 3:12 pm

Thanks. Should the rubber be real relaxed or taught? For getting it in the fuselage, I use a long piece of coathanger wire with a hook on the end.

Phugoid · Post by **Phugoid** » Sat Mar 26, 2011 3:28 pm

ADW, just use alonger stick!?

ADW 123 · Post by **ADW 123** » Sat Mar 26, 2011 3:37 pm

is the top of that thing forked?

Phugoid · Post by **Phugoid** » Sat Mar 26, 2011 3:39 pm

yup, it holds the rubber to stop it slipping off

ADW 123 · Post by **ADW 123** » Sat Mar 26, 2011 4:13 pm

gotta get myself one of those.....

Phugoid · Post by **Phugoid** » Sat Mar 26, 2011 5:53 pm

5 minutes work, nothing for a man of your calibre.......