Which drill bits for Acrylic sheet please ?

[EuroTrotters]

Hi

I need to drill some holes in plastic (acrylic) sheet.

Worried about it cracking.

Sheet is 5mm thick.

Any suggestions please ?

ET

 

[Gaston aires]

I would use tile drills started off by a very small ordinary drill. Only if it’s a smallish hole. If a large hole use a hole cutter.
Phil the drill

 

[HugoBNB]

Personally. Pilot hole using 2.5mm then final size. Sheet fully supported on MDF or similar. Masking tape on the face to prevent slippage. Slow speed. No hammer action.
Test pieces first if possible.
Good luck.

 

[meanders]

Drill speed is crucial. Almost as slow as you can take it. Higher speed will melt it, jam the drill then crack it. I prefer an old fashioned hand drill if drilling hard plastics.

If cutting a large hole with a rotary cutter, make sure it's flat and really well supported. Start from one side and go roughly half way, then flip it over to finish. Be very careful at the point it starts to break through as it will snatch.

Or approach your local school/college to see if they have a flat bed laser cutter that they will cut them for you for a decent donation. The finished holes are superb.

 

[The Wino]

I'd be worried about cracks starting from the edge of the holes. I suspect it's going to be important to make sure the fixings don't cause stress at the edge of the holes when you put it in place.

^{_{Subscribers  do not see these advertisements}}

 

[TheBig1]

Always use a new very sharp HSS bit for small holes v-e-r-y s-l-o-w-l-y

Always support the sheet from behind to prevent flexing and control break through

The other option in some cases is to heat a piece of metal tube and use that to carefully melt through the plastic, but it can result in raised edges around the hole that will need to be sanded flat

 

[PeterCarole29]

Hi

I need to drill some holes in plastic (acrylic) sheet.

Worried about it cracking.

Sheet is 5mm thick.

Any suggestions please ?

ET

As its cold you could use a hair dryer to warm up the area you are drilling first

 

[Jim]

Top Tip. If your drilling causes cracks, drill little holes at the end of the cracks to stop them spreading

 

[Steve and Denise]

Top Tip. If your drilling causes cracks, drill little holes at the end of the cracks to stop them spreading

I won’t quote the belly button joke

 

[Dave Scadding]

Hammer and bolster

^{_{Subscribers  do not see these advertisements}}

 

[Widge]

!I HAVE NEVER TRIED THIS!
But I wonder if a wood bit might do the trick, becouse it has a blade at the outside edge it might score the outside edge of the hole stopping any cracking.

As I said I have never tried it so experiment on an offcut first.

Whatever drill you use make sure it is sharp, and let the drill do the work dont force it.

 

[Wonders]

Sandwich the sheet between 2 pieces of scrap wood clamped together.
Pilot hole then full size slow speed.

 

[eurajohn]

If possible reshape a hss metal drill from the 60° angle to 120° and set you drill to a slow speed, support the workpiece and don't push too hard.
Dependant on what the hole will be used for if as a securing method ensure the hole you drill is a good clearance fit for the fastener.

 

[RobertJary]

Have a look at:

Drilling PLEXIGLAS®

www.plexiglas.de

for some useful information.

 

[Stealaway]

I always used to use one of these on my race bike fairing screens- See if you can borrow one

Small lathe centre drill

^{_{Subscribers  do not see these advertisements}}

 

[EuroTrotters]

Thanks Everyone.

Now I just need to know what Glue to use.

Aluminium - Acrylic

 

[Gromett]

Thanks Everyone.

Now I just need to know what Glue to use.

Aluminium - Acrylic

Depends...

If the join won't be visible once done, I would recommend looking at 3M VHB tape.

Outside that, too many options depending on the applications. outdoors. indoors. ultra violet protection required? Temperature sensitive zone? etc etc.

 

[TheBig1]

This is what racing teams use to bond in screens for rally and race cars. Very similar to that used with glass screens but formulated specifically for acrylic sheet and perspex

Polycarbonate Perspex Window Bonding Bond Adhesive Glue Tube | eBay

Use when bonding polycarbonate / perspex screens, 1/4 lights and side windows. Bond direct to the body of the vehicle. Other SPECIALIST ADHESIVES CORROSION PREVENTION HIGH BOND TAPES SOUND DEADENING SEAM.

www.ebay.co.uk

 

[Folkranger]

Check out how I cut this hole in situ
https://www.motorhomefun.co.uk/forum/threads/holesaw-through-perspex-splashback.246318/

 

[EuroTrotters]

Depends...

If the join won't be visible once done, I would recommend looking at 3M VHB tape.

Outside that, too many options depending on the applications. outdoors. indoors. ultra violet protection required? Temperature sensitive zone? etc etc.

Motorhome window, visible. So UV and Temperature change

^{_{Subscribers  do not see these advertisements}}

 

[Gromett]

Motorhome window, visible. So UV and Temperature change

Ahh. No idea on that one sorry. Never did anything along those lines.

 

[EuroTrotters]

Thank you all for your replies

 

[Gromett]

Motorhome window, visible. So UV and Temperature change

Please let use know which adhesive you end up using and how well it works.
With alumunium and plastic having different coefficients of expansion I am curious as to what would work and survive UV and temp changes like that.

 

[Gromett]

https://multimedia.3m.com/mws/media/1204168O/3m-vhb-design-guide-brochure.pdf

 

[L' Hobo]

Please let use know which adhesive you end up using and how well it works.
With alumunium and plastic having different coefficients of expansion I am curious as to what would work and survive UV and temp changes like that.

What about windscreen sealant, that has to withstand lots of stresses and temperature change? Cross someone's hand with silver, he might get some?

^{_{Subscribers  do not see these advertisements}}

 

[Derek’soldvan]

!I HAVE NEVER TRIED THIS!
But I wonder if a wood bit might do the trick, becouse it has a blade at the outside edge it might score the outside edge of the hole stopping any cracking.

As I said I have never tried it so experiment on an offcut first.

Whatever drill you use make sure it is sharp, and let the drill do the work dont force it.

I commissioned a sculpture made of acrylic sheets a while back, they used wood bits & wood cutting bits, masked up both sides to prevent jarring & breakouts

 

[TheBig1]

What about windscreen sealant, that has to withstand lots of stresses and temperature change? Cross someone's hand with silver, he might get some?

The window fitting sealant I linked to is designed for the purpose as some sealants will react with the acrylic. I know the likes of autoglass use a mastic to fit temporary screens. Both to aid removal when fitting the glass one and because it does not fog the acrylic. I drove round with a temporary screen in the back of my pickup truck when some scrote smashed it and it was in for 2 months without coming loose or leaking, but it was easy to pull out.

The stuff the rally teams use is super strong and needs cutting out with a blade

 

[L' Hobo]

The window fitting sealant I linked to is designed for the purpose as some sealants will react with the acrylic. I know the likes of autoglass use a mastic to fit temporary screens. Both to aid removal when fitting the glass one and because it does not fog the acrylic. I drove round with a temporary screen in the back of my pickup truck when some scrote smashed it and it was in for 2 months without coming loose or leaking, but it was easy to pull out.

The stuff the rally teams use is super strong and needs cutting out with a blade

As you probably know, a lot of Passenger Coach windows & windscreen these days are permanently bonded against the body with a sealant, the one I blagged and used on some of my Coaches is made by Dupont and is called BETASEAL 1580. This is the stuff I wrote about.

As you say, this also has to be cut out with a blade.

IF this is suitable for acrylic, I have no idea but I thought I would mention it to be investigated as an alternative?

 

[Bleau’s]

Pick the brains of FT in tias i always do when over in Lanzarote so trythere local branch near you