Introduction: How to Oven Form Acrylic
What you need:
Acrylic
Oven
Baking Sheet
Aluminum Foil
Timer
Felt - for handling the acrylic and to prevent scratches
Tools for forming
Tools for forming may include:
a Mold - any object/shape you can press the acrylic into to give it shape
mallet and/or a peen for shaping
Caution, Ive only tried this in an Electric Oven. I cant recommend for gas ovens.
Im forming the flatware and using 2 forks and 2 spoons I already have to shape my acrylic fork and spoon.
I also turned it into a video, you can watch that down below or click through the rest of the steps.
Step 1: Preheat Oven to 300 Degrees Fahrenheit
Simple enough.
Step 2: Unwrap the Acrylic From Its Protective Sheets
Easier said than done.
Step 3: Bake and Set the Timer
When oven is at 300, place the plastic on a piece of aluminum foil on the baking sheet. Set timer.
Time varies depending on thickness of the plastic. I heard 15 minutes for each 1/43 thickness was the rule of thumb.
My particular acrylic is 3mm (.123 or 3/253), I put it in for 5 minutes - worked great for my thickness.
Step 4: Remove From the Oven
The acrylic should be fairly malleable and will begin to cool rapidly.
Dont touch without the felt. If youre working larger, you will probably want leather safety gloves. The acrylic at this stage will take on any shape, including your finger prints.
The acrylic might stick to the foil. Gently rub it with any smooth object and it will pop right off.
Step 5: Forming
Immediately begin to form. When plastic is on the felt begin to push into the mold/form.
Press acrylic into place for about a minute, until the plastic is no longer moving.
Youre done.
29 Comments
5 years ago
Per United States Plastic Corp. website:
http://www.usplastic.com/knowledgebase/article.aspx?contentkey=583
Never heat acrylic sheet in a kitchen oven. Acrylic sheets give off highly flammable fumes when decomposed overheating. These gases are potentially explosive if allowed to collect in an unventilated area.
Most kitchen ovens do not have accurate temperature control. Temperatures can be off as much as 75°F (42°C), possibly allowing the acrylic to overheat.
And because air is not forcibly circulated in a standard kitchen oven, the fumes will accumulate. When they come into contact with the heat source, there is likely to be an explosion. Repeat: DO NOT heat acrylic in a kitchen oven.
8 years ago on Introduction
FYI, tonight I oven bent 10mm acrylic. I baked it at 180 Celsius (350 F) for about 12min. I was only putting in a simple bend so I used wood blocks cut at the angle I needed, one for each side of the acrylic plus the cool metal bench to press against. The 10mm bent as a curve rather than a tight angle, which is fine for my project. The inside of the angle has the impression of my wood block! If someone needed a tight angle I suspect thinner acrylic would be easier, or perhaps heat it for longer. As I need the rest of the acrylic relatively straight and one of my pieces has bent a little out of line, I decided not to risk additional heating. ;-)
8 years ago on Introduction
Dear Kiki! Thank you for the great tutorial. Definitely will try it.
But I can't understand, how it's possible to be "15 minutes for each 1/43 thickness was the rule of thumb". So you need to put a 1/43 thick sheet in the oven for 15 minutes? Correct me if I'm wrong but if the sheet is thinner you'll need less time. I think it should be 15 SECONDS.
13 years ago on Step 3
3mm is about 1/84 inch, not 3/253. Your numbers seem to be off, but I'm glad the timing worked for you.
Can you add some links to your references? You say you "heard 15 minutes for each 1/43 thickness", but I can't seem to find good consistent sources anywhere on the internet.
Reply 8 years ago on Introduction
My ruler says there's about 25mm in one inch, so 3mm would be about 3/25ths of an inch.
Reply 8 years ago on Introduction
3mm = .11811 inches
1/84 = .0119047619
3/25= .12
I think the thousandths we're arguing is probably negligible to the heat forming, although I do admit your decimal is prettier than mine.
Reply 13 years ago on Step 3
Sorry for any misinformation, I'm just a student currently and experimenting for the first time. Thanks for the correction.
I couldn't find any consistent timing anywhere either. I heard "15 minutes" from my professor for the class I was making the flatware for, Doug Bucci. Or you can find his blog here. I don't remember correctly, it was either an answer someone else had told him or he figured from his own experimenting.
I hope that helps.
Reply 13 years ago on Step 3
No worries! I'd just like to learn more about working with plastics in this way and am a little frustrated about not being able to find consistent information. I think the time and temperature varies a bit by manufacturer and other factors, so we'll just have to practice and play it by ear.
13 years ago on Introduction
Has anyone used a gas oven instead? thanks
Reply 8 years ago on Introduction
I just found this post, and for whatever it's worth, yes — this definitely works with a gas oven. I had set my gas oven to to 300°F and placed two, 12-inch acrylic, translucent-blue tubes (about 3mm thick) on the center rack. They tubes were malleable after about 5 minutes. I used thick winter gloves to remove the tubes and I quickly shaped them by hand, like clay. They were almost hard after 40 seconds, so I would shapes them a little at a time and then place them back into the oven for another 2 minutes between steps. I did this about 3 or 4 times before being satisfied. The acrylic was still resilient enough that if I did not hold it in place, it would slowly try to return to its original shape, so once I was done I quickly dosed it in cold water. During heating there was a smell, but it was not horrible and certainly did not ruin anything, though I would recommend having a window open. I also would not recommend keeping the acrylic in the oven for more than 20 minutes total, as it was starting to melt and fuse to the tinfoil and anything longer could definitely cause greater problems to air quality and the oven.
Reply 12 years ago on Introduction
final product had bubbles from the gaseous nature of the oven :/
Reply 13 years ago on Introduction
I read somewhere that fumes are given off that could be explosive
Tony
11 years ago on Introduction
Is this method able to be done on a larger scale such as a mold of my on face or something more simple such as a large lense for a mask? if someone who knows could email me at flexo123@hotmail.com or best.casey@gmail.com that would be awesome thanks
11 years ago on Introduction
Pardon me if I'm being dense here, but are these "safe" to eat off of? Will they breakdown or give off nasty chemicals as time goes on?
12 years ago on Introduction
Haha, If only.
If only i had found this instructable earlier. Turn's out oven's don't like some of the paper sheeting on the pieces of the acrylic. It also turns out lungs don't like acrylic fumes. It also turns out neither does the oven. Soo in the end i've been poisoned by fumes, particles and now i need a new oven. If only heyy.
: I
12 years ago on Introduction
Did it fume out your oven? Is there any smell left afterwards? I don't wanna have cookies that taste like plastic after this...
Reply 12 years ago on Introduction
Nevermind. I tried it. Only a slight smell left afterwards, to those wondering.
13 years ago on Introduction
This is really terrific! I would have never thought of shaping it this way. Have you ever tried cutting it with an xacto knife while it is hot?
Reply 13 years ago on Introduction
No I haven't. That's really interesting, I've never even thought about it.
Have you tried it, did you get good results?
14 years ago on Introduction
What kind of felt did you use? It seems like wool-based felts tend produce a bit of lint at times, but I'd be nervous using the acrylic craft felts because it seems like they could be susceptible to melting from the heat too...