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General Category => General Discussion => Topic started by: dannyboy on May 25, 2016, 09:53:00 PM

Title: Drilling perspex sheet
Post by: dannyboy on May 25, 2016, 09:53:00 PM
I am in the process of constructing a control panel and want to cover the top in perspex. As long as it is done reasonably slowly, I am presuming that it is okay to drill the fixing holes using an ordinary drill bit  ???. Can anyone who has fixed perspex in this way confirm that I am correct in my thinking? Many thanks.  :beers:
Title: Re: Drilling perspex sheet
Post by: Farmer chap on May 25, 2016, 10:02:38 PM
Hi,

Yes perfectly ok to drill with a sharp twist drill.

Best to use a small pilot drill first and don't force it through and maybe support the perspex.

Ian
Title: Re: Drilling perspex sheet
Post by: Sprintex on May 25, 2016, 10:06:03 PM
I drilled mine using a wood bit as it scribes a circle rather than putting outward pressure on the material

(https://upload.wikimedia.org/wikipedia/commons/thumb/2/25/Drill_tip_spur.jpg/200px-Drill_tip_spur.jpg)

:thumbsup:


Paul
Title: Re: Drilling perspex sheet
Post by: dannyboy on May 25, 2016, 10:10:02 PM
Ian and Paul  :thankyousign: (Handy tip that Paul - what I mean is, what you said, not the picture of the drill tip  :)).
Title: Re: Drilling perspex sheet
Post by: Zogbert Splod on May 25, 2016, 10:15:24 PM
Don't drill so fast that you melt the plastic. The more blunt the bit, the slower you must go. COMPLETELY support the material and drill small hole first and come up in steps to the size you need. Don't rush and you will get a good result.
Title: Re: Drilling perspex sheet
Post by: austinbob on May 25, 2016, 10:22:05 PM
Next time you need clear plastic better to use polycarbonate rather than perspex. Much easier to drill and machine.
:beers:
Title: Re: Drilling perspex sheet
Post by: Newportnobby on May 25, 2016, 10:24:36 PM
When I purchased my 5mm thickness perspex I was told to make sure it was well supported before drilling, drill slowly with an HSS bit, put some masking tape down first and to allow 10% extra on the hole size as perspex can expand in very hot weather.
I sourced mine at a boatyard who do window conversions and the owner uses his product on his own model railway. I just haven't got a round tuit yet as the timing isn't right construction wise.
Title: Re: Drilling perspex sheet
Post by: dannyboy on May 25, 2016, 10:29:22 PM
Quote from: austinbob on May 25, 2016, 10:22:05 PM
better to use polycarbonate rather than perspex


I only put perspex cos I can't spell polycarbonate  :). Seriously, it is a piece I have left over from somewhere and I do not know if it is perspex or polycarbonate, but I appreciate all the replies.  :beers:
Title: Re: Drilling perspex sheet
Post by: NinOz on May 26, 2016, 05:16:40 AM
Advice from the tradesmen at my former work ( they did a fair bit of perspex and melamine cutting, drilling and engraving : making HV control booth panels mostly) was to use a correct perspex drill but if using a metal drill make sure it is dull as a fresh sharp drill can grab and crack the perspex, especially if using a hand held drill .  Slow feed rate and, if thick, pause to cool and clear the cut plastic.  A drill press is best.

http://www.diydoctor.org.uk/projects/cutting_and_drilling_acrylic.htm (http://www.diydoctor.org.uk/projects/cutting_and_drilling_acrylic.htm)
http://www.wikihow.com/Drill-Plexiglass (http://www.wikihow.com/Drill-Plexiglass)
Title: Re: Drilling perspex sheet
Post by: Bealman on May 26, 2016, 06:58:07 AM
I've always reckoned that perspex is notoriously difficult to work with. Indeed, a workmate of mine sliced his hand very badly cutting the stuff.

I needed a piece for an Arduino project I'm currently working on, and a mate gave me an old piece that was too big. I managed to cut it to size by scoring both sides with a Stanley knife, and then snapping bits off with long nose pliers. I was then able to file it smooth.

Basically I think the trick to working with perspex is to take your time and use care.
Title: Re: Drilling perspex sheet
Post by: Geoff on May 26, 2016, 10:14:38 AM
I have worked with perspex for a number of years now and there are different types, some are brittle and some are more forgiving, I have found that drilling a pilot hole with a small drill bit first ie 3mm to start is the way to go, I then use the drill size I need then drill half way with that and turn the perspex over and drill through this stops any splits occurring.

You do need to fasten the perspex down if its a not a big piece as it can attach its self to the drill bit while drilling and you end up with a windmill and we do not want that.

Perspex can melt so take your time and if you see this happening then your drill bit is either to blunt or you are running at a to faster speed.

Hope that is some help.
Title: Re: Drilling perspex sheet
Post by: Takamine on July 02, 2018, 04:48:56 PM
Hi all
Don't mean to hijack the post but had my share of fun this weekend with perspex for a miming panel. Then I found a step drill and it makes it so easy - thanks to youtube. Just drill the hole - slight pressure and medium speed and cuts clean every time.

Got a set on the web  - not overly expensive

Here's a before and after


(http://www.ngaugeforum.co.uk/SMFN/gallery/67/6449-020718164651.jpeg) (http://www.ngaugeforum.co.uk/SMFN/index.php?action=gallery;sa=view&id=67146)

The double circles are using step drill - the others are all normal HSS drill. You can see the shatter marks even on the 2.8mm led holes and the big crack speaks for itself - so start again........
Title: Re: Drilling perspex sheet
Post by: Takamine on July 02, 2018, 04:53:46 PM
And here is the drill

BR
Chris
(http://www.ngaugeforum.co.uk/SMFN/gallery/67/6449-020718165341.jpeg) (http://www.ngaugeforum.co.uk/SMFN/index.php?action=gallery;sa=view&id=67148)
Title: Re: Drilling perspex sheet
Post by: ntpntpntp on July 02, 2018, 08:37:26 PM
For drilling this sort of stuff I always ensure my drill press is on its slowest speed, and work my way up through drill sizes applying as little pressure as possible and letting the bit do the work.  Support the workpiece with scrap wood.  I've not tried a step drill bit but worth considering.
Title: Re: Drilling perspex sheet
Post by: The Q on July 03, 2018, 08:24:28 AM
You are better off using drill bits specifically ground for drilling acrylic..

https://www.theplasticman.co.uk/products/tools-drill-bits-etc.html (https://www.theplasticman.co.uk/products/tools-drill-bits-etc.html)

they are much less likely to "grab" the plastic and cause chips and splitting..

there are much cheaper suppliers around, that was just the first site I came across with them..

found  cheap ones on EBAY
https://www.ebay.co.uk/sch/i.html?_odkw=drill+bits+for+plastic&_osacat=0&_from=R40&_trksid=m570.l1313&_nkw=drill+bits+for+plastic+slow+spiral+drill&_sacat=0 (https://www.ebay.co.uk/sch/i.html?_odkw=drill+bits+for+plastic&_osacat=0&_from=R40&_trksid=m570.l1313&_nkw=drill+bits+for+plastic+slow+spiral+drill&_sacat=0)
Title: Re: Drilling perspex sheet
Post by: Takamine on July 03, 2018, 05:16:39 PM
Hi all

Just some additional feedback on my experience on the step drill. As the name implies a single bit has multiple sizes so cost saving on buying - bought a set 3mm to 15mm for less than £6. In testing, there is no grabbing and it just works. Drills clean every time and no issues yet.....  only issue is watching you don't go to the next size when at correct hole diameter.

I found this tip on YouTube from guys that rebuild arcade machines and regularly drill Perspex - their recommendation tried and tested 😄

Works for me and thought I would share.

BR
Chris
Title: Re: Drilling perspex sheet
Post by: Newportnobby on July 03, 2018, 07:20:35 PM
Quote from: Takamine on July 03, 2018, 05:16:39 PM
Drills clean every time and no issues yet.....  only issue is watching you don't go to the next size when at correct hole diameter.


An old trick I use when drilling to a size/depth is to wind some masking tape round the drill leaving the correct length before drilling. Just drill down to the masking tape then. That's the cheap way.
I have seen collars used with a small bolt in the side to tighten down onto the drill but it only does the same thing.
Title: Re: Drilling perspex sheet
Post by: Mr Sprue on July 05, 2018, 12:08:47 AM
Quote from: The Q on July 03, 2018, 08:24:28 AM
You are better off using drill bits specifically ground for drilling acrylic..

https://www.theplasticman.co.uk/products/tools-drill-bits-etc.html (https://www.theplasticman.co.uk/products/tools-drill-bits-etc.html)

they are much less likely to "grab" the plastic and cause chips and splitting..

there are much cheaper suppliers around, that was just the first site I came across with them..

found  cheap ones on EBAY
https://www.ebay.co.uk/sch/i.html?_odkw=drill+bits+for+plastic&_osacat=0&_from=R40&_trksid=m570.l1313&_nkw=drill+bits+for+plastic+slow+spiral+drill&_sacat=0 (https://www.ebay.co.uk/sch/i.html?_odkw=drill+bits+for+plastic&_osacat=0&_from=R40&_trksid=m570.l1313&_nkw=drill+bits+for+plastic+slow+spiral+drill&_sacat=0)

Or if you have a bench grinder sharpen the point to 60 degrees. A standard drill point angle is about 120'

An approximate simple drilling speed guide for Acrylic (Perspex®)

1/8" drill = 3500 rpm
1/4" drill = 1800 rpm
1/2" drill = 900 rpm
1" drill = 450 rpm

If your drilling deep holes you should "peck" the drill to prevent it clogging. If drilling a number of holes then put a little water in a small container to use as a coolant to dip the drill bit in, this will prevent it getting hot and melting the stuff!
Title: Re: Drilling perspex sheet
Post by: mr bachmann on July 05, 2018, 06:22:59 PM
should you manage to scratch the PX , don't worry it can be polished out using the finest wet 'n dry paper (wet)  then polished with T cut or Brasso .
Title: Re: Drilling perspex sheet
Post by: Phoenix on July 05, 2018, 07:26:06 PM

I just got the "new in" newsletter from 4D modelling co which I get a lot of stuff from.
As well as some different blends of ballast, some stone wall sheets (a bit big for our scale) they have Perspex sheets now in .....

http://modelshop.co.uk/Shop/Item/Perspex-large-sheet/ITM8015 (http://modelshop.co.uk/Shop/Item/Perspex-large-sheet/ITM8015)

All best wishes
Kevin



Title: Re: Drilling perspex sheet
Post by: Takamine on July 07, 2018, 07:13:40 PM
Hi all

Well redid mimic panel with step drill. Used a hand held power tool - no drill press and found it very easy. Looks like this and you can see how close some of the holes are - no mishaps at all! There are one or two starry edges where I was overenthusiastic with the pressure - learnt quickly to let the drill feed. Its great to be able to do this without waiting for something to go wrong.

BR
Chris


(http://www.ngaugeforum.co.uk/SMFN/gallery/67/6449-070718191305.jpeg) (http://www.ngaugeforum.co.uk/SMFN/index.php?action=gallery;sa=view&id=67281)
Title: Re: Drilling perspex sheet
Post by: Takamine on July 07, 2018, 07:21:49 PM
Which will look like this  - very happy with the result

BR Chris


(http://www.ngaugeforum.co.uk/SMFN/gallery/67/6449-070718192139.jpeg) (http://www.ngaugeforum.co.uk/SMFN/index.php?action=gallery;sa=view&id=67282)
Title: Re: Drilling perspex sheet
Post by: Caz on July 09, 2018, 08:39:12 PM
That looks superb Chris, nice panel.   :thumbsup:
Title: Re: Drilling perspex sheet
Post by: daveg on July 09, 2018, 10:33:58 PM
Excellent!

Dave G