DTFB edge treatment

[cee-eff]

Built my first DTFB plane from plans - a Viggen (I'll buy kits from here on out, though!). First flight was not completely successful but the repairs were quick! What I'd like to see is a segment about treating FB edges, with closeups of the finished products to determine if I'm the only one who's messy with hot glue. I'd like to see:

* Glueing a skewer to an edge. My small test was OK, but needed too much cleanup;

* How to taper or round an edge, if possible, to eliminate the square cut. I tried the hot iron technique but the foam created a bulge behind the taper;

* Any other edge treatments that have worked.

Thanks.

 

[nerdnic]

Ironing is the cleanest way. Like with any technique it takes practice. The bulge is from too high heat and pressing to hard to fast.

 

[Gryf]

I usually use a thin application of hot glue, then scraping with a notched DTFB squeegee. It stays relatively neat if you don't go overboard with the glue.

On the other hand, I've covered a couple of my FT planes with clear packing tape, butting the tape edges with no overlap. If your DTFB edges are straight (meaning, not curved), you can apply tape along the edge first, wrapping it over before taping the top and bottom of the surface. It gets a bit trickier on a curved edge like a Spitfire wing.

Gryf

 

[Kurt0326]

If your looking for easy and lightweight, I've sealed the ends with wood glue or elmers glue. It makes it a little harder to peel.

 

[sconner]

This is a topic I recently started experimenting with. In the past I simply tried to add a small amount of hot glue between the paper, then using the side of the hot glue gun tip rolling the paper over onto the glue closing the end. It works, but is messy and doesn't seem to really close the gap completely. It's the quickest and easiest I've found yet.

Two other options I'm testing now is
1.) Using clear Gorilla Glue - Polyurethane glue lay a thin bead between the paper in the channel created by the laser cutter. Then using little scraps of foam board squeegee the excess off regularly turning and throwing away the ones with glue. (I'd recommend gloves. That glue is nasty to get off your skin!) Place it in a place with the edge facing up for best results. Make sure it's over paper as it sometimes drips if you get too much. Once dry, it makes a nice round edge where the glue foams up and dries to make a hard, light weight edge. I sand smooth before painting.

2.) Using Hot Wire Foam Factory glue, again fill the gap and let it dry. It doesn't foam up near as much, if at all. Gives a decently hard edge but doesn't fill the gap.

Seems the best looking option is the poly glue. It's time consuming, and messy. But if you do a good job it leaves a great rounded, hardened edge that is quite protective. I'll try to post some pictures if I get a some time.

Steve

 

[sconner]

Here is a picture of the edge using Hot Wire Foam Factory's Styrogoo. Filled to the top, squeegeed flat with the top and then hardened. Very firm, but still somewhat flexable as compared to the clear (white when dried) Gorilla Glue.


Here is a picture of the Gorilla glue, once again, fill the gap, squeegee flat and then let to dry. This is untrimmed. I also didn't quite fill this one all the way. See the next two pictures for a better example.


I then did a little trimming and sanding and this is what you get. It goes fairly quick.


Same piece from a different view.


As you can see, the poly glues although a bit tedious to fill the gap and spread, it produces a very nice edge once you cut off the little warts.

 

[Larry Laitner]

use the lowest iron setting that will work

Experiment with a scrap to find the lowest heat setting that will melt/round the edge. It takes more time to do it with the coolest iron, but a hotter iron does more damage to the foam. Take your time. If some of the melted plastic oozes out past the paper, just slick it down with the iron. Paint your plane after the rounding process. It will look great and be very tough. The paper will bonded to the foam very tightly and the edge will be very dent resistant.