# Tip for putting screws into plexiglass



## treeman

When I was building my router table I needed to attach the plexiglass door to the cabinet. I had a couple of brass hinges that would work but I needed to attach these hinges to the plexiglass door. I could have drilled through the plexiglass and used brass machine screws with a nut on the back but I didn't have any in the shop and didn't want to make a trip to the hardware store to get some.

I tried drilling a pilot hole into a piece of scrap and using the screws that came with the hinges. Every time I did this, I either chipped the plexiglass or stripped out the screw head. This stuff is too hard and brittle to readily accept a wood screw.

I solved the problem by placing the screw on the end of my magnetic screw driver and using a butane lighter to heat the screw for about 5 seconds. I then screwed it into the proper sized pilot hole and it went in smoothly and held strong. It stuck out on the back a little so I removed it from the door and screwed it through a piece of scrap plexiglass the same thickness. I then used a Dremel tool with a cut off disc to trim it flush with the plexiglass. When I reinstalled the screw into the hinge it was now perfectly flush with the back of the door.


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## Dennisgrosen

thank´s for the tip
my way of doing it is to drill the hole just a tyni smaller and make a tread were the machine
screw match works every time for me
but I think nomatter how you do it both solutions solve it and you have to take care when you
scew them in and not do it too tight

Dennis


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## Kindlingmaker

Great tip! Thanks.


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## davidpettinger

Here is a set of instructions given out by the Aircraft Mechanics Guild. May help us with our projects.

Sawing flat sheet:

In sawing flat sheet as for windows etc., this sawing can be done very easily on an ordinary table or circular saw, only cross cut or finishing blades should be used. Saws should turn at least the speed as recommended for lumber. Smoothest cuts; will be obtained by keeping the blade adjusted to a low level and by not rushing the work through the Saw. This causes melting and allows the blade to stick to the Plexiglass.

Drilling holes in Plexiglass:
The drilling of holes in Plexiglass seems to be the big bugaboo among many aircraft mechanics. The principal difficulty lies in that drills as sharpened for steel are used, it is near impossible to drill a hole in Plexiglass without cracking using a drill that has been sharpened for drilling steel and especially so if the hole is much larger than 3/16 diameter. Drill sharpening for Plexiglass is relatively simple, in general take the drill as sharpened for steel and just grind off or dull the cutting edge. The object is to sharpen the drill so that it scrapes its way through the plastic. Lower the angle of the flutes, this is done by setting the angle of the drill sharpening jig to 12 degrees which gives the cutting edges a toal od 120 degrees from tip to shank edge. This is the proper angle.

A drill used in drilling steel will not work for drilling Plexiglass, due to the fact that it digs in, causing cracks.

A drill sharpened for Plexiglass does not dig, but scrapes it's way through the Plexiglass.


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## PurpLev

thanks for the pointers treeman and UnionLabel. might be using plexiglass in the next few weeks… probably as a floating panel which does not involve drilling - but does involve cutting it down.


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## a1Jim

Good tip thanks


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## chriswright

Good tip, I wouldn't have thought of that, but it makes sence.


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## PaulfromVictor

Do you think a small Forstner bit would make a clean hole ?


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## cliffton

easiest way i found to drill holes in plexiglass is to cut the head off a nail of the size i need and use it to melt its way through. for anything larger than 3/8 inch ill drill small pilot hole and use a forstener bit to drill the bigger hole.


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## 559dustdesigns

I used to install car stereo for about ten years and I used Plexiglass a lot in high end installs. There are some help full hints like if you want to drill holes in plexi, I like to use a small bit then move up to the larger bit. Dennisgrosen mentioned using machine screws. To use them, you can tap the plexiglass just as you would metal. The plexi can over heat your cutting bit or blade so I learned to spray wd40 on the blade of the table saw every 6 inches while making the cut. Also put masking tape on the glass where your cutting or drilling. The tape helps keep the glass from chipping and you can place lay out marks on the tape with a ball point pen. I had to display electronic components behind these windows so I came up with ways to dress up the edge of the plexiglass. It comes with paper protecting it, I used to mark off borders and remove paper (with a razer blade) on the back of the panel. Next with a coordinating color, spray paint the unmasked section. When you remove all the paper you have a nicely finished border. The paint on the back side really looks nice. To add lettering, I applied vinyl stickers that are cut back words which are applied before the paint. One could put a logo like Porter Cable or Bosch on their router station. Here is some of that work. Hopefully it is helpful and can be applied to one of your woodworking projects.


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## 559dustdesigns

Treeman, I never used heat for drilling plexi before. I have heard you can heat the edges of the glass with a torch to get it to look polished or smooth, but haven't tried it. Thanks for the tip and That router station is really nice.


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## jeletta

I found this site when I was trying to attach a plexiglass top to a frame on desktop that I use for art pastels. When I couldn't handle the hot screws, I tried heating the drill bit and it "worked"! The screws went in like a charm. I thank you for the heating tip…..


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## 33706

I use brad-point drill bits, and feed slowly into the work.


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