Removing fixed port frames

[Saunter]

I want to replace the crazed glazing in my fixed ports (windows). The glazing is held in large aluminum frames approx 10" x 30" each. The mounting screws are easily removed, but the frames are still being held in by ancient sealant. I spent half a day removing one by brute force and prying tools. The frame got bent and scratched, as well as the adjacent gelcoat. There must be a better way. The cabin wall is about 1/2" thick plywood bonded to the fiberglass outer molded cabintop. I've thought of using a tiny pin router between the frame and cabin. Also, some sort of hot knife might work. Are there any experts out there who know better than me?

[darylat8750]

Not an expert but I've heard that oscillating tools with a smooth blade work great for this.
The Best Oscillating Tools: We Put 9 to the Test - Popular Mechanics

[Saunter]

Thanks,
I've never used an oscillating multi-tool, but it looks like just the ticket. I'll have to raid the cruising kitty and get one!

[jongleur]

Maybe piano wire and two dowels? Lemme know
if this works, 'cause I'd like to try it.

[FlyingCloud1937]

Set up 4 to 6 clamps, one in each corner, use a 2 X block now screw down the clamps until they have pressure equal to a hard double hand twist.

Now take a heat gun and heat the frame, working as equally as you can imagine.

Increase the tension on the clamps, as you heat.

Bang, they pop!

Lloyd

Originally Posted by Saunter

I want to replace the crazed glazing in my fixed ports (windows). The glazing is held in large aluminum frames approx 10" x 30" each. The mounting screws are easily removed, but the frames are still being held in by ancient sealant. I spent half a day removing one by brute force and prying tools. The frame got bent and scratched, as well as the adjacent gelcoat. There must be a better way. The cabin wall is about 1/2" thick plywood bonded to the fiberglass outer molded cabintop. I've thought of using a tiny pin router between the frame and cabin. Also, some sort of hot knife might work. Are there any experts out there who know better than me?

[billr]

My wife and I have had to a lot of them. The key is to realize the sealants use will flow with force over time; and heat helps too. From a standpoint of cheap tools for this, go to a thrift store (Salvation Army, etc) and buy maybe 15-20 of used steak knives (maybe a couple of bucks total). Those can be used a thin wedges to slowly pry up the edge around the perimeter, but take the whole process slowly (and heat helps). That way, you won't mess up your rim. Also, serrated knife edges help cut the old seal. We mix these with an assortment of wood chisels to be used carefully for wedges. We have taken off a lot of 3M5200, and it can be done if you have patience, the right tools, and lot of time.
Billr

[keepondancin]

Put a couple of layers of masking tape around the frame to protect the gel coat. Use either the steak knife, or the blocks and clamps and heat, or the oscillating tool(my first choice), bot also make up some oak wedges with a fine edge. Drive them in equally around the frame as it loosens to keep pressure on breaking the sealant. You will need to try all methods to see what works best.