I'm back. I got the last few gussets made for the roof and took everything to the welder so the roof is gone for a couple days. I want to do some of the finish work on the rear deck and deck lid while the roof is out of the way.
If your edges look more like butchery than artistry, fear not. When I made the deck lid, I left plenty of room to fit into the opening since everything surrounding the deck lid is permanent and not adjustable. Now it's time to tighten it up. There was some wobble along some areas of the deck lid edges so I had welded 1/8" metal rod along the edges in those areas and smoothed them out so I wouldn't need to add duraglass on a very thin edge like that. The surrounding surfaces have a lot more surface area so I'll use Duraglass to bring the outer edges in to the deck lid.
First step is to scuff the primer lightly by hand with some 80grit. Then mask inside the jamb. Back tape the deck lid with the tape hanging out beyond the edge and close it. The additional tape will keep the Duraglass from sliding down into the opening.
Duraglass itself is too thick to do what I want here. I won't be able to press out the bubbles down in the gaps. You can thin it down by adding about 10% fiberglass resin. Mix it thoroughly before adding the hardener. Spread it out and let it run down into the gap. Don't do too much area at a time, I need to catch it just as it starts to kick. Too soon and it is still soft and will drag along with the blade. Too hard and it won't cut.
I use two single edge blades and a scrap of 3/16" steel with some vice grips holding the whole mess together to cut the gaps in.
Cover the gap pushing down lightly. Since the Duraglass has been slightly thinned it will sag down along the verticle surface of the opening and stick like it was welded. It has a very strong bond.
Watch it closely and check it by touching it with your finger. If it sticks to your finger, it's still too soft. When it starts hardening, run the double blades through using the edge of the deck lid as your guide. If you caught it at the right time it should cut easily and leave a thin strip in the middle. Use a small pocket screw driver to lift the strip out and let the Duraglass finish hardening and move on to the next section. The cut will be straight and clean but it will need additional flilling and sanding further down into the opening.