General Category => Plans, Projects, Building and Flying Tips => Topic started by: Deerslayer on September 23, 2018, 08:52:45 AM

Title: More Fun With Foam(board) = Paper Removal
Post by: Deerslayer on September 23, 2018, 08:52:45 AM
I used to use the Adams foamboard, as stocked by $Tree, for my flying contraptions. The paper is easily stripped off, you can then either leave the foam sheet alone or paint it.

As more folks started building foam planes, often the FliteTest Spitfires, etc., I saw that they left the paper on. Part of the reason seemed to be the difficulty in removing the paper covering. I wondered why, since it always came off easily for me. Then one day, to my great horror, $Tree was out of foamboard just when I needed more. So, I tried Dollarama. I found the foamboard and later discovered that the paper was extremely difficult, sometimes impossible, to remove cleanly. The reason? Their foamboard was made by Elmers, not Adams! Now, I understood what Flypaper and others had been talking about.

I have built a number of planes, usually flying wings, using the Dollarama/Elmers foamboard. Apart from the first time I bought some white, they have only stocked black. I did develop a technique for carefully removing strips or sections of the paper, if desired. Otherwise, I left it alone and usually painted it over with thinned Polycrylic to waterproof it, possibly even tarting it up with some colored craft water-based acrylic.

The black Elmers foamboard is interesting, in that the foam itself is black, yielding a somewhat higher visibility surface, almost sparkling in direct sunlight.

If you need to laminate a couple of sheets together, say, for a stiffer fuselage or to layer up a KFm style wing, you have a choice with the Elmers, but not with the Adams. You can strip the paper off or leave it on, then use sprayed or brushed water-based contact cement. Note: Don't leave the paper on the Adams foamboard, at least where you need to glue it, as your structure will pull apart easily.

So, to cut to the chase:

I want to use the Adams foamboard, but I want to remove the paper. How to do it? Very simply - use drug store alcohol! I use the Life brand 99% USP isopropol, although the more diluted alcohol will probably work. I spray or dribble a generous amount onto the surface, it should be in a thin puddle, and leave it for a few seconds. Then, I start lifting the paper. I may keep dribbling, spraying or brushing more alcohol into the interface of paper and foam as I pull it apart, using a very shallow angle. If there is a spot where the paper seems to be coming apart, stop pulling, load it with alcohol, or begin paper removal from another side or edge. After all the paper is removed, if there are any spots of paper fibres, soak them and rub or carefully scratch them off with something like a credit card.

While you think about this, here is a great way to create a hinge with the Adams foamboard, if you decide to leave the paper in place:

Take a balsa stripper, or make up a tool with a fresh #11 glued to a block of wood, such that the blade will protrude just a hair less than the thickness of the foamboard with its paper attached. Run it along your hinge line, the idea being to cut ALMOST to the paper on the other side. Then, crack your hinge open. Now, you can carefully cut a bevel into the one part of the structure, say, on the Rudder, and leave the other part alone.

You will be able to move the surface freely; if there is interference, or to just clean things up a bit, you can carefully sand the exposed foam surfaces. The paper is very strong, you will not damage it, as long as you are careful. Even if you do nick it, there should still be more strength that you will ever need to use.

If you wish, you can always wipe a thin layer of hot glue across the exposed foam in your hinge. It is very unlikely that, even if you do nothing, the paper will ever separate from the Elmers brand foamboard - unless they change their formula or technique for manufacturing.

You can, of course, do the same hinging technique  with the Adams stuff but you WILL have to use hot glue or something along the hinge line to ensure that the paper will not separate from the foam.

Try it. Good luck!
Title: Re: More Fun With Foam(board) = Paper Removal
Post by: Wilf on September 26, 2018, 06:51:45 PM
Thanks Gary, I have had a miserable time trying to make a matching pair of wing panels for my FT Explorer but the don’t curve evenly therefore don’t match. The reason, the paper would not strip where needed. I will try your technique with the incohal “HIC”.
Title: Re: More Fun With Foam(board) = Paper Removal
Post by: Deerslayer on December 29, 2018, 06:09:44 AM
Here is a new, very important discovery in the world of penny tech!

An altenative to the usual foamboard has occasionally shown up in the various  Dollarama stores in Kingston. Note: not Dollartree

Aside: Who knew that we have so many Dollaramas around here?

It is called UCreative, with a big, colorful label stuck on it. All sheets are white base but one side has been very lightly coated with a color, typically Yellow or some sort of Red.

Important features:

1. No paper covering.

2. Construction. It is obviously 2 layers of material bonded to form a very stiff sheet that is slightly thicker than either of the paper-covered foamboard products we have been using.

I think that this material is the same as Depron, which is just one company' s name for its polystyrene sheet products.

If you want some, you may have to shop around. I discovered it at the new Cat Center Dollarama several months ago. When I went back a few months later, there was  none. I checked at the downtown store; a shelf stocker guy thought he knew what it was, even checked out back for me, but no luck. Then one day, I found some at the RioCan store. Yippee!

What a great find is this product, for those who hack out foamy flying objects  - a fraction of the price of "official" hobby shop Depron, very disposable!