Ok Plastic Welding requires a few things.
First off the you have to find out whether the Plastic you want to weld is Thermoform or Thermoset. We are after Thermoform.
Tools you require is a Plastic Welding Gun.
Plastic Welding Rod
Ok the test to find out if Plastic is Thermoform by using the tacking tip on your Plastic Welder and push it into the Plastic. If it melts and sinks into the Plastic it is Thermoform what we are after. If it just slides and doesn’t sink in it’s Thermoset and we can’t weld it.
Whenever Plastic Welding we must make sure the Plastic Welding Rod is the same Material as what we are trying to weld.
We then scrape the Plastic to be welded to remove any Oxidization and use Alcohol wipes to clean the Plastic we are to join.
This ensures maximum bonding ot the Plastic Welding rod.
Once you set your Plastic Welding Gun to the correct temperature, you will have to trial this and experiement on scrap to enure you have the correct settings.
You can then begin Plastic Welding by heating up the rod first and then simultaneously heating the Plastic, using a pendulum motion.
You will see the Plastic Welding rod begin to bond and you will feed it into the Plastic whilst moving the heat along the Plastic.
Then you can trim off the excess rod with a knife.
You can also speed weld using the speed welding tip that is an extra when you purchase a Plastic Welder.
I find Speed Welding is excellent as you obtain a much stronger weld due to the extra pressure involved in feeding the Plastic Welding rod.
For larger work as in Plastic Tanks it is advisable to use an Extrusion Welder. These are expensive but you can usually hire them out at a reasonable rate. These guns are excellent to use as they are fully programmable using a prompting selection guide which sets the Temperature of the gun and also the feed of the welding rod for you. All you have to do is weld. These guns create a much stronger weld suitable for large tanks, and have a greater area of penetration.