Food grade plastic water tanks your DIY tips for welding plastic

What is polyethylene? It is your family friendly food grade plastic or known as Polymer sheets. This plastic does not contain dyes and has small amounts of recycled plastic in it.

But it is regulated by the U.S. Food and Drug Administration or known as the FDA.

They tell us we have to use a plastic with a greater purity than other plastics used for non food items, 9 quality of being pure.

Small key: remember when welding plastic, keep in mind that it is a thermal plastic, which means it will melt to itself.

This is a great article that goes in depth to help explain the, "how to" of plastic welding. Basic principles of Hot Gas welding for Thermoplastics. Plastic welding, PDF

...Drum roll please...High density polethylene, yes that is a mouth full! But don't let that intimidate you.

"Let's say it all together now", high density polethylene, HDPE...lol...I have to entertain myself!

If you can get past the name high density polyethylene, you too can learn how to weld plastic. Food grade plastic that is...

HDPE is used for milk, juice, water containers and most five gallon food buckets and shopping bags are made from it.

Small key: The food grade polyethylene plastic that we picked up was the natural high density polyethylene sheets.

*Natural is the white in color.

Food grade plastic is excellent because it is impact resistant, high tensile strength, low moisture absorption and chemical and corrosion resistant properties.

In order for you to build these boat water tanks, you will have to purchase polyethlene sheets, you will need them quarter inch thick, forty eight inches wide, by ninety six inches long. Also diameter HDPE welding rod.

Small key: **Important, make sure when your polyethylene welding that you use the same plastic rod as the material you are welding together. If you don't it will not weld together correctly.

It is very easy to cut with any wood working tools. Use a plastic cutting blade or the Dewalt DW #3176 blade on the circular saw or table saw. Most of the other blades cause too much heat and the plastic will melt to it. The edges can be finished with a router

Make sure you clean all dust, dirt, oils off of the food grade plastic before you weld. Lacquer thinner, alcohol, mineral spirits do the job just fine.

Ok, How to weld plastic so you can DIY and build your boat water tanks?

Before you can start welding plastic you need to prep these plastic sections and treat them like you would when welding aluminum or any other metal.

Come on it's not that bad!

Such as good joint prep, air pressure and right heat, the right plastic welding rod or also none as filler (what you use to join the pieces), and the right tip for your welding gun. Make sure you heat up the plastic piece you are welding until it is soft, doughy or plastizied.

If you can work with wood you should have no problem with this plastic. You can use the same wood working tools like circular saw, jigsaw, and router bits, they slice through it like butter.

Small key: you will have plastic shaving just like when you are cutting wood except there will not be any dust.

Make sure you clean all dust, dirt, oils off of the plastic before you weld. Lacquer thinner, alcohol, mineral spirits do the job just fine.

The great thing is the plastic will not rust, rot, mold, and it is also an insulator and chemical resistant.

Keep it simple when trying to figure out your pattern, shapes, sizes, curves of your water tank. Use free cardboard boxes as a pattern and lay it down on your sheets, trace them and cut them out. This way you have one less thing to worry about!

For our plastic water tanks we welded the pieces together as in this example, Figure 2 welding plastic magazine.

The water tanks in Magic Dragon are surrounded by aluminum shell on all sides except for the top, as you can see in the pictures...

Small Key: This type of food grade plastic has been used to build this boats refrigerator liner, fresh water tanks, shower sump, shower bottle holder, battery boxes, engine drip pan, and many more small items.

This product is also known as Polymer sheets, the FDA, US food and drug Administration requires food grade plastic used for food or drinking water to be free of what contaminates (quality of being pure).

This material has been used to build this boats refrigerators liner, fresh water tanks, shower sump, shower bottle holder, battery boxes, engine drip pan, and many more small items.

The great thing is the plastic will not rust, rot, mold, and it is also an insulator and chemical resistant.

I wanted to give you several examples of plastic welding to give you guys a better idea. Keep in mind there are all kinds of different plastic welders out there, but they all accomplish the same thing.

Here is a link to plastic welding and hot air welding hand tool...The hand gun for plastic welding, video

This water tank holds...one hundred gallons

If you have extra left over, go ahead and make yourself a cutting board!

Welding Plastic: How To Instructional video by Techspan.

Return from Food Grade Plastic welding-plastic to Sailing Home Page

New! Comments