Cutting circles

[Hawkwrench]

I need to cut about 4 styrene discs. 020 thick and 3/8 wide. Any recommendations as to what's the best for such small disks?

I've looked at the Olfa one and it doesn't go that small. 

 

Tim

[LSP_Kevin]

I use a circle template and a needle in a pin vise for this kind of work. In the image below I'm cutting an oval hatch using a similar technique:

 

 

Kev

 

[Hawkwrench]

So just run the needle around the inside of the circle on the template???

 

Tim

[LSP_Kevin]

1 hour ago, Hawkwrench said:

So just run the needle around the inside of the circle on the template???

 

Tim

 

Yep! Just tape the template down firmly so that it's less likely to move. You'll also have to press it down with your fingers, as the needle will really want to push it out of place as it goes around. The thicker the styrene, the less successful this method tends to be, and you need to focus on keeping the tool as vertical as possible. Start lightly and try not to dig the needle in with too much pressure. Tricky, but it works pretty well given the right conditions.

 

Kev

[allthumbs]

Another technique for creating circles of this size is to bevel appropriately sized brass tubing to a sharp edge, creating a metal punch that can be struck into the sheet of plastic with a hammer.

[Hawkwrench]

54 minutes ago, allthumbs said:

Another technique for creating circles of this size is to bevel appropriately sized brass tubing to a sharp edge, creating a metal punch that can be struck into the sheet of plastic with a hammer.

That's a good idea. 

I'll try Kevin's and your idea each.

 

Tim

[Greg W]

FYI

 

Pricy, but it will easily and precisely cut 3/8" holes and discs in thicker plastic sheet.   

 

https://www.micromark.com/Precision-Disk-Punch-Set

 

 

[dmthamade]

Sometimes you can use old brass from shooting, sizing may be limited.

Don

[alain11]

another way , however a little bit expensive ( you can find it to different price ), but very useful to cut even very small circle , that works on thin plastic sheet too ...... find it 

Alain

 

[scimitarf1]

21 minutes ago, alain11 said:

another way , however a little bit expensive ( you can find it to different price ), but very useful to cut even very small circle , that works on thin plastic sheet too ...... find it 

Alain

 

For the price of this a Cricut or Silhouette cutter is not that much more expensive and they are much more versatile.

[alain11]

1 hour ago, scimitarf1 said:

For the price of this a Cricut or Silhouette cutter is not that much more expensive and they are much more versatile.

hi

you are right , the " Silhouette cutter is way more " versatile " . If I  dare to say , the limit , is your imagination , but its prise is from 150 Euros to 250 Euros more or less 

" my" tool  , is .......25 to 66 Euros .....more or less , but............. we are limited to cutting only ...... circles 

[Bob MDC]

Automotive/aerospace "wad punches" should be able to buy the size you need

https://www.amazon.co.uk/s?k=12mm+wad+punch&adgrpid=103193631246&gclid=Cj0KCQjw4cOEBhDMARIsAA3XDRioCxc093F8CIqDTYHGZV920aeKVqIyviMQvww44ngBX4dwHEOmkJgaAhATEALw_wcB&hvadid=448575748304&hvdev=c&hvlocphy=9044859&hvnetw=g&hvqmt=b&hvrand=5267704876836837296&hvtargid=kwd-434161278377&hydadcr=27348_1726524&tag=googhydr-21&ref=pd_sl_7o561k0szu_b_p50

 

Bob