Bending a strip of perspex into a circle

[plewlandsbob]

Hi,
At work,I need to bend a strip of 6mm thick perspex, into a 750mm diameter circle. I tried doing it cold, but it snapped as it was almost there. Tried heating with a hot air gun, moving along, while pulling the perspex round, but it seemed to snap easier, if anything. Has anyone got any tips or techniques?
Using perspex, as that is what we have available.

Alternatively, what would be a more flexible type of plastic, to use?

Thanks
Bob

 

[Parm]

Are you bending it around a former?

It will need controlled heat and probably two pairs of hands

It can be done

 

[500e]

Have used electric fire, old type.
You have to get it hotter than you think, but not to hot that it flows and upsets clarity.
The person who helped
worked at Derry&Toms as a window dresser and made stands for display
Even heat both sides was one of the things she said was a requirement ,

 

[Barking Mat]

Hot air gun, and the will of god.

 

[optima21]

polycarbonate/lexan is more flexible than perspex, but I think you'll need a flexible wallet to pay for it.

 

[plewlandsbob]

Are you bending it around a former?

It will need controlled heat and probably two pairs of hands

It can be done

No, it is to fit inside, part of a machine. Just clamped one end, with a pair of vise grips and tried to bend it round and in.

 

[Turbo]

As you've found perspex does not bend easily, even when heated.

What you need is polycarbonate, will not snap when bent but you might need some heat to help.

 

[Anguz]

does it need to be 6mm ? whats the application?

 

[6ply]

Hi,
At work,I need to bend a strip of 6mm thick perspex, into a 750mm circle. I tried doing it cold, but it snapped as it was almost there. Tried heating with a hot air gun, moving along, while pulling the perspex round, but it seemed to snap easier, if anything. Has anyone got any tips or techniques?
Using perspex, as that is what we have available.

Alternatively, what would be a more flexible type of plastic, to use?

Thanks
Bob

We use a strip heater. Is that 750mm circumference, 238mm diameter?

 

[plewlandsbob]

It is a 750 mm diameter.

Yes it needs to be 6mm. It is to go inside, the spinner housing, of a machine for dispensing pig feed, to act as a wear strip, to prevent metal from wearing out. The machine manufacturer closed down, a few years ago.

 

[Keith 66]

Perspex or Acrylic will bend easily, we used to do it all the time at school. Hot air gun or oven will do it, trick is to keep the gun moving & get it hot. You have to watch you dont overheat sections as it will bubble & boil if you do. Once you get it hot enough it goes really floppy.
If it wont bend it aint hot enough!!! Heat proof gloves are a good idea & something to hold it in position once bent.
Being a good insulator it will retain the heat far longer than you expect & cooling with water will help.
Alternative plastic that bends at lower temperatures is PETG, that can be formed easily.

 

[Agroshield]

If it won't bend it ain't hot enough

I think I read last night that it needs to be 160 degrees or so. Would you think a cheap thermometer gun would help him in this?

 

[Mark 2]

3 layers of 2mm?

 

[Keith 66]

A cheap thermometer gun isnt really needed, we used to lay the acrylic on a sheet of steel to protect the bench, as you heat it the acrylic will warp a bit due to the back being colder, or hang the strip up & play the gun on both sides. Keep the heat gun moving. It goes floppy really quick once you get up to temp. 160 degrees c is about right. Gloves are good as you will burn your fingers without.

 

[plewlandsbob]

Thanks for your help guys.

It is now bent and fitted in place. Fired up the space heater and held the strip, in front of it, to heat it. Used an offcut ,to test it first and got it soft enough, to fit no bother.

 

[Pete.]

Thanks for your help guys.

It is now bent and fitted in place. Fired up the space heater and held the strip, in front of it, to heat it. Used an offcut ,to test it first and got it soft enough, to fit no bother.

Nice work. High volume lower heat beats focused high heat every ti.e in these circumstances.