I remember we used silk back in the day on models that would not last long, like combat.  Price was $1.00 per square yard.  Used nylon on stunt and scale airplanes.  I used to have enough patience to cover with either and not have wrinkles.  Just enough dope to seal and go fly.

Campbell's Custom Kits, Peck Polymers, Micro X, Aerodyne, FAI supplies, and other freeflight sources have either Esaki silk, or very similar, in a variety of colors.  It is near $20 a yard.  If you amortize that over the thousand flights you will put on your airplane, it is not much.  The Dharma silk I have seen is considerably heavier, but people get good results with it.  I don't expect to run out of Esaki silk, some marked $1.95.

I have covered several airplanes with the silk and have had no problems. Still working on using up the 5 yards I purchased. Good stuff as far as I'm concerned, can't see paying 25 bucks a yard for basically the same stuff.

I tried some of the heavier stuff and found it way too heavy for anything except front end reinforcement.  The 5.5 mm is OK for covering.

I just received my Darma 5mm silk, it looks to have a denser weave than what I used as a kid, but with the tighter weave it should take less dope to seal.  I will be trying it soon possibly on my Continental, but I want to run some comparison test with Polyspan. I want to see how well it shrinks up and how much dope it takes to seal and when sealed how much it weights compared to polyspan.  But for the price it is a hard deal to beat.
Andy

Hi Ty,

How did you like the Polyspan on the I-Beamers? (not a hijack, just a "covering" question! LOL!!)  It is a lot faster to apply than silk, so I am considering that possibility.  I am still going to use the Dhrama Silk on the Airon.

Bill

Used Poly-span on both the Staggerwing and Spifire by Sheeks.   

Hello Folks,
  Re the problem of using 10 coats of dope to seal the silk. What I do is to cover the wings with mylar. The very, very, lightweight stuff that the free flight competition guys use. I thin down impact adhesive and paint that on the wings, then use a modelling iron to tack down the mylar and finally go over it, to shrink in place. This covering weighs next to nothing. Then cover with silk and use a single coat of dope (use the dope as an adhesive).
  You finish up with a very tight covering that imparts lots of rigidity to the wing structure and it is very lightweight indeed! The silk plus mylar is a LOT lighter than the silk and 10 coats of dope! The mylar seals the wing and the one coat of dope shrinks the silk.

Regards,

Andrew.