Building Tips and technical articles. > Paint and finishing

How I Cover With Silk

(1/8) > >>

larry borden:
After being away from the hobby for a gazillion years, I decided to start building control line airplanes again. It also helped that we had moved to a place that allowed me to have a circle in my back yard. I decided to go 'old school' with my planes, silk and dope.

I did a how to cover with silk on the other forum, but it was lost when the forum crashed.

It seems there have been quite a few out there that have an interest in covering with silk, so here goes.

After I have the plane sanded to my satisfaction, I brush on a few coats of nitrate dope to seal the wood. Nitrate seems to seal better than the butyrate.

larry borden:
The next step is to cut a piece of silk to cover the wing. I cut it about an inch or so larger so I'll have something to pull on when it comes time to stretch the silk. I cover the wing with the grain/threads of the silk going span wise.

After I have the silk in place, I take a spray bottle of water and spray on the silk. This helps to keep the silk in place while I apply the nitrate dope to attach it to the wing. I then stretch the silk to make it tight and then apply nitrate dope to the perimeter of the wing.

After applying the dope, I keep stretching the silk as the dope is drying. I still use t-pins to hold the silk in place around the tips.

To avoid warps, I silk the top and bottom of a panel and then do the other panel the same way. The excess silk is easy to sand off after the dope has dried.

larry borden:
After I have both wing panels covered, I apply nitrate dope the perimeter of the wing until the LE, TE and tips are smooth.

I spray several coats of thinned tautening nitrate dope to fill the silk. I spray the wing panels, with several coats of clear until the silk is filled. At this point, I spray a couple of coats of non-tautening butyrate, before applying color coats.

After I have applied all my color coats, I let the plane gas off for a couple of days. I apply any graphics and then spray the plane with several coats of Brodak's crystal clear. At this point it's time to finishe the plane and go fly.

If anyone has questions please feel free to ask. Hope this has been some help.

Jim Thomerson:
What Larry says is good stuff.  My experience is with Esaki silk, some packages which I bought for $1.95 many years ago.  If I am doing a diesel powered airplane, I go nitrate all the way. If a glow airplane I go butyrate all the way. I put enough non tautening dope on all surfaces which will touch the silk to make the surface shiny.  If you don't do this, the open bays will get shiny and the wood will still show the silk grain because the dope will wick through. I put the silk in place, then wet it.  I get it really wet, which is another reason to do a good dope job on the wood. The silk can be stretched tight and the water will hold it in place. 

As Larry says,  keep the weave straight.  Silk is very easy, but you must be patient and demand perfection.  Once it is in place, I go around the edges with dope thinned at least 70% thinner.  This will adhere to the underlying dope, and blush.  If it is a constant chord wing I will demonstrate my expertise  ::) by starting at the bottom trailing edge, going around the leading edge, not sticking to the leading edge, and back to the top trailing edge. I stick it down there and on the ends.  Keep everything wet, and hang the wing vertically so the silk dries evenly and does not pull in a warp.

Once dry, I brush on several coats of tautening dope, thinned 70% thinner.  This will go through the silk to start, but will not make the puddling effect.  I do a couple of panels, then turn over and do a couple of panels.  Once most of the pinholes are filled, I go to progressively thicker non tautening dope until it shines to suit me. 

If I am going to use tissue numbers and letters, I put them on before going to the thicker coats, just sticking them down with thinner. This presumes you are doing a clear or tinted finish.

Fellow's I sure do thank you for these "hints". I am planning to silk a wing soon.
  One of the things that I noticed is use "tautening" dope on the first few coats.
 I have been covering with silkspan on several, well all, of my models for a loooong time and just recently have been using "non-tautening" dope and the paper is plenty tight enough, was wondering if this will work with silk also??
  Many years ago I tried covering with silk, and at that time all we had was Aero Gloss dope, after a while the silk split l/e to t/e between all the ribs!!
  Haven't used silk sinse..
  Again thanks for the advise... n~


[0] Message Index

[#] Next page

Go to full version