What did I do wrong?II

[granpa]

I had for me a good covering job on a Fokker DR1. I used light silkspan for covering and I covered wet. Final stage I applied 50/50 dope and now the entire plane is covered with waves in the silkspan. Murphy's law...the thing has to have 3 wings!

[granpa]

Waves remained after 2 days...Bummer

[Wildpig]

You said 50/50 dope, do you mean 50/50 water and white glue or dope/thinner mixture?

What did you attach the silkspan to the model with?

Yeh, it would have to be a tri-plane.

[granpa]

The 50/50 was dope and acetone. I used Elmers and water to attach the silkspan....Dennis

[atesus]

Hi Granpa,

I'm not sure about thinning dope with acetone. Are they compatible, I have no experience myself? If acetone is useable as thinner, then your problem may be caused by high humidity? If the humidity is high when you're doping the tissue, there's a chance that the finish will have white spots/blotches. If that's the case, going over the wing with thinner (but on a drier day) should cure it.

Another potentially possible scenario is that there may be white glue (Elmer's) residue on the tissue which makes it behave differently towards dope compared to areas that are clean. I don't know what to do for that, paint maybe?

I hope this helps,

--Ates

[paul]

Granpa
I feel so sorry for you having come so far with your build
I too have the same problem when it comes to the final stage of the build and ends up a disaster

You are not alone

[ADW 123]

Re atesus's response, you can thin dope with acetone as long as the dope is the fuel proof kind like aerogloss. I use acetone for mine and It works every time. I agree with the comment on the white glue. if there are spots of white glue on the tissue the finish might look strange. take pictures so we can see what you are talking about

[Bill Gaylord]

This experience is reminding me of my electric DR1 experience. I used a so-called lightweight iron-on covering, before I knew about the real light weight iron-on coverings. It's a tank at 6oz, but it flies. Would be a lot better at 4.5oz though. I can relate to three wings being quite a chore to recover, especially when assembled. I had to reset the incidence of the top two wings on mine. Somehow I got in there with a blade and cut the glue between the struts and the wing, and then reset them. My consensus with putting any more effort into the model now is, "Aw heck we'll build another one someday". Considering that I acquired and gave away a Guillows DR1 kit recently, I'm not sure if that will even happen.

[granpa]

On april 4th I reported on a covering job gone bad, well shame on me. Each day I checked on my covering job but today I got a surprise....All better, back to the orginal covering befor the application of the 50/50 dope. Please do not ask me how......Dennis

[Bill Gaylord]

On april 4th I reported on a covering job gone bad, well shame on me. Each day I checked on my covering job but today I got a surprise....All better, back to the original covering before the application of the 50/50 dope. Please do not ask me how......Dennis

Good to hear it shrunk tight. Reminds me of my painted Coverite Microlite iron-on jobs. When you first paint them, they wrinkle like a prune. After drying a full day, nearly all or sometimes even all of the wrinkles disappear, but it takes a full 24 hours. Very light heat gunning with a high power hair dryer takes care of the rest, but I've learned to wait a day before doing that. I used to get impatient and try to shrink them out right away, but now I've learned to let them dry and shrink out as much as possible, before applying heat.

Humidity!

Using dope below 70* farenheit and dope too thin will slow drying time, also.

I learned that lesson with epoxy. For whatever reason, just a few mere degrees can be so critical. I've found that if the initial curing starts at too cool of a temperature, that it never sets properly, even if moved to a warmer location. It likes to start curing at it's ideal temperature, right from the "get go". I imagine dope and other compounds can be like that also.