This insturctable will go through how I turn milk bottle tops (and various odd ones) into blanks for working with, mainly for turning but you can work it just like timber so your imagination is your limit :)
To start off with you need LOTS, just to be clear here LOTS of milk bottle/coke/fabricsoftner tops I get various places like cafes, staff canteens an family to save them for me just ask whoever you can.
A mold, this should be near the shape/size you want to use less caps, in my case im making a bowl so i used a bowl. If you want to be safe have one that you can melt into at 200 celsius because trying to melt it and move molds is unplesnt the lids retain loads of heat and stick to most surfaces so its just asking to cause serious burns.
An oven to melt it in. an expensive bit of kit but if you look hard in the kitchen (the place you take the lawnmower apart when it breaks before you manly shave the lawn) you might be as suprised as me that you already have one. (same applies to the mold the next cake my wife bakes will have plastic in it...)
And a work shop or tools to create! in this case a lathe was all i needed
Step 1: Wash and Dry
This is a really important step if you don't want material that smells of old milk and this is also a good time to remove any of the little silver seals stuck in the lids.
Step 2: Fill Your Mold
Fill you mold with the caps and back as hot as you can. The lids are HDPE which is a recyclable thermoplastic (can be heated and reshaped) which softens at about 120 Celsius but we want to go as molten as possible so high heat (I was at the 220c mark) these will liquify for lack of a better word and sink to the bottom so keep topping up with caps till you reach your desired fill level, at this point if your very well equipt stick it in your vacuum chamber to get the air out but alas is don't so i must suffer air pockets in my work (its good you sell them and proof of fully hand made recycled item) now switch the oven off and let the blank cool slowly in there to stop it warping this will take 8 hours plus if its a large blank.
Step 3: Remove the Blank
this was a gamble as i usually do this in loaf tine paper cases so the just lift out but this time i decided to see if glass would keep it loose, it didn't until i stuck it in the oven at 200 for 5 minutes then up ended it which should work on all smooth molds? but wont leave the mold completely clear. this can be remidied if really needed with more heat just burn it out after scraping any big bits off the hot surface.
Step 4: Make!
Whatever you want to i've done pens, bottle stops, garden dibbers and now a cereal bowl.
This isn't a wood turning tutorial (i can do one at some point if its wanted) but I will take anyone interested through my process (everyone works differently especially with turning)
I mount the blank between head tail stock as centered as I can by eye (brilliant tool impossible to buy a new one even from screwfix so put a protective case on yours such as goggles) and then make it true round from said centers and the shape i want before cutting a rebated dovetail in the base for my chuck jaws to expand into and grip.
clean the base as you wont have it spinning at 2000rpm and accesable at the same time after this.
spin the blank round and grip with the jaws and turn out the center which ever method you prefer as the all work on plastic do a clean pass on the outside and the rim aswell and make it all nice and clean and then out have a bowl.
Step 5: Done
my first suggestion is save the shavings or any other type of HDPE you can get as they can all be melted together.
second suggestion is be really creative with ideas and if you can implement them let me or others in the comments know about them so we can try them.
third is tell me off for grammar and spelling as needed as I'm more comfortable with a chainsaw then with writing stuff.
And lastly if you like this idea or instructable spare me a vote?
All the best making and breaking and thanks for reading
Third Prize in the