|1 forum posts|
I need to cut some 56mm diameter polycarbonate discs from 2mm thick sheet, with no hole in the middle.
Have so far tried
- hole saw in bench drill. - teeth get very quickly clogged up , bit like sawing mdf.
- fretsaw/piercing saw - pretty tatty edge , which takes forever to sand down to anything remotely respectable.
- lathe face plate , - difficult to make a tool that cuts cleanly without clogging up.
teenage daughter came home from school and dismissed my attempts saying I needed a laser cutter like they have in D+T.
useful suggestions welcome.
|Flying Fifer||07/02/2012 23:47:14|
|180 forum posts|
Agree with your daughter laser is the way to go. Modern lasers give a very fine finished edge with no tool marks and consistent dimensions. All you need is is to draw the circle the size you want in Corel draw or Autocad, load to the laser & cut as many as you want.
4659 forum posts
With aluminium I would use the backgear because you get almost no heat.
Things clog up when you have too much speed because of the heat.
It may be a "cutting speed" thing with your perspex too
Try slower speeds and a nice sharp tool
|Jim Guthrie||08/02/2012 08:37:14|
|102 forum posts|
Edited By Jim Guthrie on 08/02/2012 08:38:18
|maurice bennie||08/02/2012 09:32:43|
|164 forum posts|
Hi Capanab, I always cut perspex circles by cutting roughly with hacksaw and then grind to edge of circle with my 6" grindstone .To accurately cut straight lines ,Clamp to top of bench with steel straight edge.Make a cutter with a Stanley knife by grinding a hook cutter on the blade and pull it along the line of the steel.Leave the edge of the plastic slightly over the edge of the bench so the cutter comes of without digging into the bench.With 1/8"plastic cut about half way through and bend the plastic upwards and it will crack of.With 1/4" its easier if you cut both sides..Practice on some rough first.
Good luck Maurice.
PS you dont have to cut right through.
|Les Jones 1||08/02/2012 10:19:45|
|2234 forum posts|
Cut them out roughly with a hacksaw (Rough octagons) cut out a wooden disk just less than the diameter you require and centre drill it.
Mount another block of wood in the chuck and turn the end down to just less than the diameter of the finished disks and face the end. clamp the disk (or disks) between the blocks of wood using a live centre. Turn to the finished size taking light cuts. An alternative is to stick the disk to the block of wood in the chuck with double sided adhesive.
|470 forum posts|
...and the Oscar goes to - Les!
Strange that one has to wade through 6 mostly off-topic answers for finding the only sensible one.
Btw, polycarbonate is neither perspex nor alu.
|19 forum posts|
Ask teenage daughter to make some in her D+T class!
Brand new good quality hole saw does work if run slow and eased through gently.
Too much force or speed and things get a bit warm and sticky.
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