It´s possible to fuse PET together ?

[RaZias]

In Europe there isn´t PL premium, altough I know some european sites that sells glues that make the same effect.

I was wondering if it would be possible to heat two layers of PET with a heat gun so they would get sticked togheter.

I am not talking about the techniques...I know that the bottles will possibly get heavily deformated, I am speaking in gluing 2 layers and just that.

After I will think in the bottles.

What would happen if I put PET inside the Heat-gun ? Would it make a hot-PET-glue ?

[Spaceman Spiff]

In Europe there isn´t PL premium, altough I know some european sites that sells glues that make the same effect.

I was wondering if it would be possible to heat two layers of PET with a heat gun so they would get sticked togheter.

I am not talking about the techniques...I know that the bottles will possibly get heavily deformated, I am speaking in gluing 2 layers and just that.

After I will think in the bottles.

What would happen if I put PET inside the Heat-gun ? Would it make a hot-PET-glue ?

Hi! I think the answer to your question is ultrasonic welding!

[Stevo14]

I've had some success in the past with "welding" various pieces of PET together using a large hex screwdriver head heated on a gas stove. I think the key here is temperature control. If you get the plastic too hot, it starts to oxidize (turning a shade of yellow-brown-black) and become brittle, which is not what you want in a pressure vessel . Here is a picture of my best (strongest and best looking) weld to date. You can see that I was able to keep the temperature mostly under control, but there are still places where the plastic got too hot.

PETWeld.jpg (528.9 KiB) Viewed 85 times

[rockets-in-brighton]

I've had some success in the past with "welding" various pieces of PET together using a large hex screwdriver head heated on a gas stove. I think the key here is temperature control. If you get the plastic too hot, it starts to oxidize (turning a shade of yellow-brown-black) and become brittle, which is not what you want in a pressure vessel . Here is a picture of my best (strongest and best looking) weld to date. You can see that I was able to keep the temperature mostly under control, but there are still places where the plastic got too hot.

PETWeld.jpg

Interesting, what pressure can that hold? (and welcome to the forum)

[RaZias]

Can you post a picture of the tool you used next to that bottle, I want to know the head size of the tool you used.

That is really a innovate technique.

[Stevo14]

I've never actually done a pressure test on this weld in the traditional sense. I worked on this method for some "hydrogen" rockets that needed better airflow between bottles. I found that a good weld was able to hold the momentary high pressure from the exploding hydrogen, and that a bad weld riped apart. When the weather is good, I will do a more traditional pressure test.

Can you post a picture of the tool you used next to that bottle, I want to know the head size of the tool you used.

I actually used two different sizes depending on exactly how I needed to weld the plastic.

toolscale.jpg (332.04 KiB) Viewed 72 times

It was easiest to use when I could hold it like a pencil. Anything that is long and thin and can hold the tool head will do.

[Spaceman Spiff]

I've never actually done a pressure test on this weld in the traditional sense. I worked on this method for some "hydrogen" rockets that needed better airflow between bottles. I found that a good weld was able to hold the momentary high pressure from the exploding hydrogen, and that a bad weld riped apart. When the weather is good, I will do a more traditional pressure test.

Can you post a picture of the tool you used next to that bottle, I want to know the head size of the tool you used.

I actually used two different sizes depending on exactly how I needed to weld the plastic.

toolscale.jpg

It was easiest to use when I could hold it like a pencil. Anything that is long and thin and can hold the tool head will do.

That's very innovative. By welding the thick parts of the bottles (neck and bottom) you don't get shrinkage and the plastic dissipates the heat better preventing fast crystalization.

Nice job and welcome!

[Stevo14]

I did the pressure test today and the weld sprang several pinhole leaks at about 4 bar (~60 psi) but did not rupture. I don't have the equipment to test above about 5 bar (~75 psi), but I think strength is not the problem. Making it leak-free will be harder and might require a sealer on the inside of the bottle.