Cutting / Drilling Sheet Perspex

KenMcCulloch

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One of this winter's projects is to make a new panel for my electrical switchgear, engine panel and TinyTach. I have found some nice black acrylic sheet which will look a lot nicer than the rather sad looking sheet of cheap plywood it will replace. I have to cut 3 rectangular openings and drill various holes for assorted switches. Any recommendations for particular tools, techniques, types of drillbits etc to use/avoid?

I am a reasonably competent woodworker but have never worked with this material before. I have a good cordless drill that will do very slow speeds which I suspect is right, and an electric jigsaw. Anything else needed?
 
There was a recent topic regarding drilling perspex hatches one here.
Try a search for it, if I recall there were some others that had sucessfully drilled perspex
 
I find a very sharp but coarse wood cutting blade in the jigsaw best for cutting it (counter intuitive - e.g. Bosch T118B). Cut oversize then finish with a router to give a classy finish to the edge (I'm not brave enough to try flame polishing!). I find it drills OK with normal metalworking drills, but others will give you info on how to re-grind the drill angles to make them work better. The enemy is heat, so sharp blades, and slow feeds are the order of the day.

Leave the protective film in place until you have finished the machining!

Loads more information on machining here

Andy
 
This webpage will be of interest. I suggest that you take note of the advice on drilling when it comes to largish holes for switches.

There is a workshop manual to download as well. I have not looked at it so don't know what is in there.
 
Use masking tape to mark hole positions, it will stop the drill sliding. My friends also blunts down his drills slightly so that they do not catch as they surface on the back of the sheet
 
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I have a good cordless drill that will do very slow speeds which I suspect is right, and an electric jigsaw.

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You need high tool/cutter speeds and very light feed pressure. Make sure the perspex is fully supported - you can do this by using a backing sheet of ply, stuck on with double sided tape - especially when drilling, as it helps to prevent the drill corkscrewing its' way through the last bit of the hole when it breaks through.
If you have a bench grinder it helps to grind the rake angle to 90 degrees, so it scrapes rather than cuts.
A jigsaw is ok but use a blade with plenty of teeth, not a coarse one. Again, keep the blade speed high and use a light feed pressure.
If the cut edges are on show on the finished panel, you can file, wet n' dry and Brasso to get a polished finish.

Edit: 90 degrees - should that really be 0 degrees? Look at fig 7 on this page here - http://www.mmsonline.com/article.aspx?id=14722 - they call it 'dubbed'.
 
Hi, I worked with plastic sheet material, number plates. If you score the sheet deeply it will break as you bear down on it. You must bear down on both sides of the score with the score at edge of a flat surface. If it is small then a vice to hold one side will help. Try on some scrap till you are an expert. The drilling method; slow speed and back with hard wood or a scrap of same plasic, the promblem is when the drill bit clears again practice on scrap. If you use clear plastic it is great to use reversed rub down letters to name the switch, after putting the letters down spray with black paint two light coats is better than one heavy. Go have some fun and make all sorts of signs. Peter
 
I made a panel from perspex to cover my engine control panel, actually to stop peeps treading on the engine key ! I used 200 x 150 x 10 thick sheet . Using a hole saw in a pillar drill at slow speed I drilled 2 x 40dia holes (access to key & engine shut off button) & cut joining tangents with my jiig saw, finishing off with fine emery. The finish was quite acceptable.
 
When I worked on old aircraft and mistakes were VERY expensive, we used drills with very low angles. Around 10º or less. If worried about skidding, clamp a bit of wood with the same size hole above the work to line it up. Drill presses help a lot. The jigsaw/medium tooth SHARP wood blade and router worked well for me to cut out.The high cutting speed of the router tends to heat seal the edges. A squeezy bottle of water/washing up liquid helps with the jigsaw to stop hot swarf build up. I notice my local DIY shop now has drills ground esp. for perspex and other plastic, almost flat.
Andrew
 
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