As mentioned in part 3 of this series of articles, I wanted to cover some lessons learned on the removal of paper from DTF and then sealing (other than Minwax which I covered in part 2) for maximum strength and durability.
With the paper left on, DTF is actually quite strong even before reinforcing, but is very heavy compared to Depron and MPF. Additionally, the paper can become heavy and peel off if it comes in contact with water (why it is good to treat it with Minwax). So it is a challenge to remove as much of the paper as possible while still retaining strength in critical areas and not having the paper peel off over time.
To score the paper along the areas where I wanted to remove it, I used a new, sharp blade in my #11 Exacto knife like this one. I like this knife for this process as it is lightweight and easier to use a very light touch than other knives I like to use.
However, with this batch of DTF I was using, the paper did not always peel off cleanly by hand and as I mentioned in part 2, if too much of the glue I used to secure the plans soaked through the paper on the foam, it was hard to remove and would come off in pieces. Hopefully you can see what I mean on this KF piece.
Based on what Peter had told me, I wanted to ensure the edges of the paper were sealed with glue before applying any Minwax, so after all the sanding was done around the edges, I carefully applied a very thin bead of this glue which is an inexpensive alternative to Foam Cure that I can get at my Dollar Tree store for $0.94 USD for a 1.7 oz bottle. If you are interested, you can read more about this glue here.
I also did the same process along the hinge lines of my control surfaces and along the edges of the foam like on the wing where there is paper right up to the edge of the area where the aileron is located. Time will tell if I got everything sealed correctly :)
I will continue to add articles to this series as I get more flights in and can comment on the plane's performance, strength and durability over time built entirely with DTF :).