NOTE: I sell finished mallets at my etsy store here.
The theory for making a mallet from recycled plastic is straight forward.
- Create a mallet handle
- Create a brick out of plastic
- Make a hole in the brick for the handle
- Attach the handle
So lets get straight into it.
Create the mallet handle
I drew up the mallet in CAD so I had a drawing of the handle which helped.
There is a slight taper so the head of the mallet doesn’t fly off the handle.
We have a large static belt sander in the shop that helped make this handle. Using a CNC is another option which I have used. If i didn’t have either of these i’d probably grab a plane out.
Create a brick out of plastic
This was a bit more involved than the handle. First the plastic.
Getting the right type of plastic is important. HDPE (2) and LDPE (4) are great for mallets. HDPE is what milk bottles are made of which I had access to so that is what I used. I wouldn’t use PP (5) as it can crack when impacted, so not so great for a mallet.
The first step in plastic recycling is to clean and shred the plastic. Cleaning is important to help bonding and to avoid bad smell.
The plastic needs to be dry before heating to avoid creating air pockets (through steam).
If you don’t have a shredder (and i didn’t when I made my prototype) the easiest way to shred plastic by hand is to make one of these:
Here’s a video that I looked at when making mine:
To use it, cut the top and bottom off of a bottle (I used milk cartons), feed a little bit of plastic in and then pull the rest of the bottle through.
You will get a long ribbon of plastic, then you simply cut it into pieces. I had to do about 20 milk bottles to have enough plastic for my mallet head. It looks like a lot but it will shrink.
Make the mold
Once you have the plastic shredded, you need to make the mold. The quickest way is to bend some sheet metal up. Using a vice, some 90 degree angle and a hammer is a good way to get the mold together. Using rivets will hold it together.
(Unfortunately I don’t have this anymore and couldn’t find any photos. But to paint a picture it kind of looks like a cake tin for a brick)
TIP 1: Experienced plastic mold makers will have what is called a draft angle on their mold. This is to make it easier to get the part out. Essentially instead of a 90° angle, you would have the opening of the mold bigger than the bottom.
If you have the opportunity to do this i would recommend it.
TIP 2: Make the mold taller than the mallet head you want. My height of my mallet head is around 68mm so Making the mold 100mm tall is something I would recommend. You can mark with a sharpie the line on which you want to get to with your plastic.
Once you have these two pieces you can start making your brick with the aid of an oven.
Making the mallet head
Fill the mold up full of plastic. Turn the oven on at 180°C and then regularly keep pressing down the plastic to compress it and add more until your mold is filled.
I had a piece of plywood the same size as the opening in the mold to push down the plastic and make it into a brick.
TIP 1: When I did mine I could see the plastic go from translucent to transparent when it was in the molding state.
TIP 2: Do this step in a well ventilated area. HDPE isn’t as bad for you as other plastic (source), but it still isn’t great.
When it’s finished, it will need to cool for a little while, at least a few hours for the centre to really cool down.
Make a hole in the brick for the handle
Once you are happy with your new HDPE brick it’s time to put a hole in it. Take your time marking it out. Drill out as much as you can and then clean it up with a chisel.
The hole should have a taper on it to match the handle so it fits, and also stops the mallet head from coming off the end.
Attach the handle
I used another mallet to whack the handle in. Once it’s together your ready to use your mallet.
Sounds simple right?
In theory everything is simple, so here is a bit more information in the form of questions.
FAQ:
How hot do I have the oven?
Start here, if you aren’t getting the results you want, turn the heat up a little
- HDPE = 180°C (356°F)
- LDPE = 175°C (347°F)
Where do I find more information on plastic?
For more in depth information on plastic go to this page from preciousplastic.com
What’s the easiest way to clean a milk jug?
Isn’t a plastic mallet going to break?
Is this the way you make the mallet on your Etsy store?
This article details how I made my prototype. I thought it was more useful to someone reading beause it’s easier to replicate. Now I use an extrusion machine and an aluminium mold. Here’s a vid of the process:
Is there any more resources for making a mallet like this?
I watched this guy when i started. It’s gives good detail on each of the steps, although it’s not exactly the same way that I did mine.
What happens if I don’t take the labels off?
You can see with mine there are bits of red in it. This is because I didn’t take off the labels of my milk containers.
Watch the cleaning video if you want to see how to easily take off milk jug labels.
Thanks for reading
This has been my guide on how to make a mallet from recycled plastic. I do sell a more refined version on my etsy store if you are interested, otherwise best of luck with your plastic mallet!