Ok thought I would do a quick tutorial on
how to wind coils. First you need a jig. Mine is pretty simple, a 1/2"
black iron pipe run thru a couple 7/8th bearings bolted down to a table
with a pillow block. There are three eye bolts installed near the end to
ensure that the coil gets plenty of grip when turning.
Step
one. Using a small tubing bender from harbor freight, put a slightly
less than 90 degree bend in the tubing and run it thru the eye bolts.
Step two:
After running the tubing thru the bols, turn the eye bolts at an angle
to better grip the tubing and screw them into place.
Step three:
This is the second most difficult part after the final bend after
coiling. Slowly start the tubing around the mandrel while holding it
down to keep it from kinking. Once you get this one down it gets a lot
easier.
Step
four keep turning:
Step five: Keep on turning while allowing about
an 1/8" on an inch of space between the tubing... keep holding down so
the tubing doesn't kink.
Step six: Once you get the inner coil as long as
you want it, it is time to start the outer coil. However again you need
space between the tubing for maximum effect. To accomplish this I used a
notebook cover would around the inner coil and secured with some
sacrificial zip ties. To start the coil around the tube simply pull it
over and turn while holding down.
Step 7: More
winding.
Step
8: At this point I decided to add on some cardboard tubing to increase
the final diameter of the coil to better match the exterior of 2" copper
tubing using exactly one round of cardboard. I recommend a 50-50 mix of
notebook/cardboard to create a dual size coil.
Step 9: When
you get to the end, be sure to leave about an inch unwrapped. This will
allow your uptubes to fit better. This is the really tricky part... if
you can get this done your home free. I bent the tubing carefullly with
the benders and then finished up with some channel locks and the spring
bender.
Step 10:
Cleanup of copper. Soak in warm Rid-X or weak lye solution for about one
hour then take it down to the local car wash and blow out the cardboad
with the pressure wand.
Final fit pics:
Well thats
how it is done. No salt or other BS just a nice clean coil.
Attention:
I will soon be offering these coils for sale for $50 each plus shipping
anywhere in the USA. While very easy to wind as shown above, keep in
mind that there is a bit of a learning curve. It can take hours to build
a jig, if you screw up winding one at any point and you have to start
all over again from scratch, and its a one shot affair... you only need
one coil that should last a lifetime. Time and materials can easily add
up to more than the price I am asking. If your interested in purchasing
one already completed, drop me PM for details... I take Paypal and will
be happy to list it on Ebay.