Silk Span after it dries

[Marty Hammersmith]

     My first silk span effort was using Brodak medium on a Sarpolus Challenger. I put it on wet with Windex. It relaxed like crazy and shrunk up beautifully. I'm getting ready to cover a Sig Akromaster and was considering medium silk span for it as well. However, the wing doesn't have a lot of structure. What do I do if I build in a twist to the wing when the silk span dries? Is there was way to manipulate the twist out of it.

     I do have an open package of light silkspan too. Probably enough to do this wing if you think "light" might be more appropriate for this application.

[Perry Rose]

What does Windex do that water doesn't?

[Marty Hammersmith]

What does Windex do that water doesn't?

I can't say. But, I believe in emulating success. I was a first time silk span user. Sparky says to use Windex so that's what I used. It worked fabulously so no need to change unless demonstrated to do otherwise. 

[Dennis Toth]

Marty,
Use the medium silkspan the light stuff is ok for 1/2A. Once it is dry check for warps. If you see any now is the time to address them. Just mist the panel again and jig it straight with weights. Once all is straight you can start with the clear dope. For the dope always do a whole half wing top and bottom then do the other side. I like to alternate applying coats starting on the top for one coat then after it dries for the second coat start on the bottom then do the top. Let each coat dry a few hours between them for the first 4 coats then let it dry overnight.

Check for warps along the way you can use a heat gun to add a little heat to a warped area and straighten (just bend it a little past straight, hold and let cool, you will get a feel for how much to bend). From the 5th coat on as it starts to fill the wave let it dry 3 -4 hours between coats. Usually around the 6thor 7th coat you start to see a little sheen and its then ready for the rest of the finish.

Best,    DennisT

[Steve Helmick]

I first applied silkspan wet around 1958 and don't see any reason to use Windex. If Sparky would post his reasoning for using Windex, I'd be interested in reading about it. Windex is good for applying sticker, decals, films, and cleaning bugs off my windshield.  Steve

[Dave_Trible]

The silkspan shouldn't warp your Acromaster wing.  I covered two of them with silk and had no trouble.  Providing the wing is built straight to begin with,  if you apply even coats of dope top and bottom then let them dry at the same time they will sort neutralize each other.  If there IS a warp a re-coat will usually soften it all up and the wing will go back to it's original form.  If not block the wing with a little twist the opposite direction until the dope dries.  If all a else fails   (it won't)  then a bit of steam will soften it up and allow you to twist it back.
The Windex thing...well I sort of think it was something suggested a long time ago by the late, great Phil Granderson in an article he wrote about finishing.  Maybe that is where Robert picked it up.  I think it was just the handiest spray bottle available and the Windex did no harm.   It's basically water with a bit of alcohol I think and all evaporates.  That is true of the 'original'.  I'm not sure I'd want to try the flavored versions since we don't what is flavoring them.  The Windex is pretty effective to clean the oil off your airplane at the flying field...

Dave

[Marty Hammersmith]

I am admittedly surprised at just how much the Silkspan "relaxes" when it is wet with Windex. That really helps making sure there are no sagging or wrinkles in the dried covering. I can't imagine trying to attach this stuff dry. I sort of wonder if the Windex relaxes it more than plain water? I'm just about ready to cover my new Akromaster so maybe I'll try straight water.

[Dave_Trible]

I use an old Windex bottle filled with water.....

Dave