OK, here are some updates. This time, I'll document my experience about bending aluminum moldings and trims.
I'm not an expert in this so I can't guaranty what I did will work for you too. But I found all my techniques from this forum and Google, so I feel this should work for you too.
First the materials.
I'm using "M20 Corner Insert" by All-Rite. This has 5/8" leg. This comes in 16' long so the first problem is getting the material longer than 8' long if you don't have the source near by. I needed mine at least 12' so I strapped 4" PVC pipe on the roof of my car and traveled about 400 miles to get some. I combined my vacation, so it worked out fine.

This was cheaper than freight.
This molding is used at edge of roof and wall, and hatch edges.
I'm also using "Regular Roof Edge Molding". This will be used mainly at base of walls.
Both types were able to bend with same method.
OK, here is actual bending.
I first try to bend without annealing. I haven't measured the radius, but I think it is around 6-8". And this happened.

So it's time to bring on some fire power! I think other type of torch will work too, but you need something that gets hot enough. I got BernzOmatic Mapp/Map torch.

Before I start annealing the piece, I made a bending jig.

There are rabbits on both sides of edge so that legs of aluminum can be recessed to clamp.

When I first researching annealing, this seemed very specific and technical. But the "Sharpie" method works so easily.
Basically you mark the area that you want to bend with sharpie (I don't think color matters, but I used orange and red), then heat the area with torch until the marking disappear. What I understand is that the whatever the ingredient in the Sharpie burn off at the similar temperature aluminum softens. I guess it depends on the ambient and material temperature, but it took me about 20-30 seconds.
Once you get the aluminum heated, start bending using the jig and clamps.


Here are some pointers
1. When you are bending "insert" type molding, put blockings in the insert to clamp so you don't damage the lips for insert.
2. You will have better grip and leverage to bend if you have extra length on ends. You can trim afterward.
3. When you make a jig, make it such that you count for the "bounce back".
4. Don't freak out if you see some kinks. If you annealed, you can hammer it back easily. Make sure you use wood blocks or rubber mallet.
5. I don't have it shown in the photos, but I used other clamps to hold legs from kinking.
6. Go slow. Only heat and bend small portion. For the piece shown in the photo, I probably heat and bent in 3 sections.
7. Wear heavy leather glove. It will get hot! Once you burn off sharpie marks, it's hard to see hot section. I burnt my thumb really good...
8. Go to Harbor Freight and buy a few more clamps than you think you need.
9. Make sure you follow instruction of your torch. I don't want to hear you blowing up your garage.

Thanks for looking.
