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I need some help – I am planning on using using some 1/4 mil clear Mylar on a new P-30 I am building but I do not know the best way to add some color (visibility) without adding excess weight. I am aware of the Rit dye approach but I am very concerned about the mess. My wife is also not a big fan of me using any of her large pots for dying model covering. Are there other approaches that effectively improve visibility with minimal weight penalty. Thanks
Have you thought of covering some of the Mylar with colored tissue! Go to The Pensacola Free Flight Team home page and then to articles….and look for article ..Tissue Over Myrlar…this may help you.
Dye is probably lightest.
Floral Spray (I buy it at Michael’s) seems most common, a light dusting adds little weight.
If appearance is not critical sharpie pen strokes might be lighter than Floral Spray
Cheers!Tape the mylar to a flat surface.
Now then. Two options. The first is Dykem layout fluid, available in spray cans or brush cans. Spray an even coat and wait a minute for it to dry and then apply the mylar with the color to the inside. The drawback with Dykem is that you need to like red or blue.The other option is india or calligraphy ink. You’ll need to spray it. An airbrush or a Preval sprayer will to it. Thin the ink with some dope thinner. Apply the mylar with the ink on the inside. Ink has a lot of colors available and it won’t fade. Neither will the Dykem.
You only need to color one surface. The adhesive will grab the colored surfaces without a hitch.
I use Dan’s method with Pete’s color. Get Floral Spray at Michael’s or some other craft store. It comes in a lot of colors. A very light dusting is all you need. Resist the temptation to make the color “solid”. The specks will merge when the model is any more than 10 ft overhead and it will look really great, like the traditional translucent tissue covering. The Florid Spray adds little if any weight.
If this is a gas model, and you need the added torsional rigidity, go with tissue over the mylar. See the Pensacola website mentioned above. It is no heavier than dope sealed tissue, and much, much tougher.
‘Thanks everyone for the help. I will give these each a try. I did some other research on the web earlier today and found some interesting stuff about the weight per area of various products including Japanese tissue, Nitratae dope, 1/4 mil mylar and, Microlight covering. I was surprised at how close the numbers were. Does this agree with your experience ( I am pretty new at this )? The data I found indicated that tissue with 2 coats of 50/50 nitrate would be 1.65 gm/sq ft, Microlight would be 1.9 gm /sq ft, and 1/4 mil Mylar (less adhesive or color) would be 1.58 gm /sq ft. Another question comes to mind: are the properties of Mylar a significant advantage over tissue? I know of the issue of moisture making tissue sag, but this is not much of a problem here in Arizona. I am trying to understand the options and issues. Thanks again
Bruce
Has anyone dyed any Mylar recently?
The reason I ask is that I am not having any success. So far I have tried three times unsuccessfully, two packs of the Rit powder and one bottle. The Mylar just doesn’t want to accept the color.
Now for some past history. Five or six years ago I had fantastic results. I’ve done red, blue and purple all without any trouble. Simple to do, zero problems.
Back to present date, I’m using the same crock pot, same batch of Mylar and a new batch. All following the same old Al Brusch instructions.
My only conclusion is that Rit has changed their formula. Has anyone else run into this problem.Mike
Bill Hunter wrote a article for the Oct. 1972 issue of American Aircraft Modeler on applying color to mylar. The article goes into a lot of detail on applying the color to the mylar. It is too long to publish here, but the basic idea for example is to tape the mylar down on your work bench and spray on your color, spraying works best. You can use Kandy Apple brand translucent color spray cans available at most auto parts stores. Put a thin light coat of color then let it dry and put a second coat on. Don’t try to apply the color too fast or heavy. You want the color to be translucent.You want to put the color on the bottom side of the mylar that goes against the structure, that way the color is fuel proof. Using 3M 77 spray adhesive on the wing outline you simply attach the mylar to the structure. I have the article and if you don’t have the back issue of AAM, I could always e-mail it to you or anyone else for that matter, if you provide your e mail info.
Mike
@mikeschwartz wrote:
Bill Hunter wrote a article for the Oct. 1972 issue of American Aircraft Modeler on applying color to mylar. The article goes into a lot of detail on applying the color to the mylar. It is too long to publish here, but the basic idea for example is to tape the mylar down on your work bench and spray on your color, spraying works best. You can use Kandy Apple brand translucent color spray cans available at most auto parts stores. Put a thin light coat of color then let it dry and put a second coat on. Don’t try to apply the color too fast or heavy. You want the color to be translucent.You want to put the color on the bottom side of the mylar that goes against the structure, that way the color is fuel proof. Using 3M 77 spray adhesive on the wing outline you simply attach the mylar to the structure. I have the article and if you don’t have the back issue of AAM, I could always e-mail it to you or anyone else for that matter, if you provide your e mail info.
Mike
Thanks Mike S, I have that article but now it has become a “quest” to find out why the Rit dye no longer works. I’m also a Wakefield & Coupe flyer so weight is a big concern for my models. That’s why I have always dyed the Mylar. Floral spray will be my 2nd choice if I can’t figure what is going on with the dye.
Thermals
Rit makes a new dye to use on polyester material. It is called Rit Dye More. Hobby Lobby sells it. Polyester is like plastic . Since mylar is plastic, you should try this new material. One of the things Rit recommends when trying to dye plastic type material is raise the water temp. to 180 degrees F. and maintain it through the dye process. I would try a small sample and see what happens. Are you using tap water to mix the dye? Sometimes the city water supply’s have added chemicals to its water, these chemicals could have a adverse effect on the dye. You could test for this by getting some purified water from your local supermarket and make another test. There are two schools of thought on weather to apply tissue on top of the mylar to make the wing stronger and more rigid. The other method is to put the mylar over the tissue. Either method produces the same results. However if you apply the mylar over the tissue, it is 100% fuel proof, so you could use a little less dope on the tissue and would not need any additional fuel proofer saving some weight. You can soak mylar in 100% nitro for days , pull it out and let it dry with no ill effects to the mylar. The mylar has a shiny gloss look to it over the tissue. Tissue on top of the mylar will give you the more traditional look of tissue and you can then add tissue trim. Its whatever method and results you prefer.
Mike
@MikeRichardson wrote:
@Dan Berry wrote:
Ink.
Berry, any idea why it worked a few years back and now it doesn’t?
The RIT Dye?
I would guess that the formula has changed. I would also guess that the EPA regs had a hand in the change.
I use ink. Brushed on. Spraying works but isn’t worth the hassle.Look for Rit batch numbers ending lower than 11. Lots of info here- http://www.dgcoursereview.com/forums/showthread.php?t=38339
@stevej wrote:
Look for Rit batch numbers ending lower than 11. Lots of info here- http://www.dgcoursereview.com/forums/showthread.php?t=38339
“NOW that’s what I’ve been looking for”. Thank you Steve, I had my suspicions and this confirms it. I’m going to head to the store and see if I can find that lot number. I will update my results after I cook a 4th batch.
Thermals to all
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