[swCObob]

I would like to drill a 2" diameter hole in a 12"x24"x3/8" thick piece of acrylic, to use as a bowl making jig.

What is most suitable for making the 2" center hole, a hole saw, forstner bit or my only 2" router bit, a 4 wing Whiteside spoil board bit? Would it help to use a drill press and water while cutting?

Will a standard metal bit work for safely drilling the small diameter router plate mounting holes? Thanks to anyone who has experience drilling this material. Bob

 

[old55]

Welcome to the forum.

 

[mgmine]

I used one of these expandable bits once. Not only did it cut the hole but it put a bevel on the side of the hole. So what I did was cut 3 holes each a little smaller, I then used the cut outs to make a set of rings for different sized bits. Each one nested inside the smaller one and held firmly. I may have turned the cutter so that the bevel went in the opposite direction than normal but I can't remember for sure. I cut the largest one first and went down from there and had the plastic sitting on a piece of wood as a backer. I didn't use any water, just drilled.
Mibro Adjustable-Radius Hole Cutter|Rockler Woodworking and Hardware

 

[harrysin]

I would like to drill a 2" diameter hole in a 12"x24"x3/8" thick piece of acrylic, to use as a bowl making jig.

What is most suitable for making the 2" center hole, a hole saw, forstner bit or my only 2" router bit, a 4 wing Whiteside spoil board bit? Would it help to use a drill press and water while cutting?

Will a standard metal bit work for safely drilling the small diameter router plate mounting holes? Thanks to anyone who has experience drilling this material. Bob

A hole saw in a drill press is the fastest, but this being a ROUTER forum I rout them. A standard metal bit is perfect for the small holes. No lubricant has ever been necessary in any of my projects.

 

[swCObob]

A hole saw in a drill press is the fastest, but this being a ROUTER forum I rout them. A standard metal bit is perfect for the small holes. No lubricant has ever been necessary in any of my projects.

Thanks everyone.

 

[TenGees]

The biggest issue that I've had when drilling small holes in plexi is when the bit is coming though near the end of the cut. Especially when hand drilling the bit can snag and chip on the exit. I like to use stepper bits for that purpose but they probably don't have long enough 'steps' for 3/8 inch.

 

[roxanne562001]

Welcome to the forum I would use a hole saw no water bore half way through then flip it over and bore it the rest of the way or use a fly cutter as mgmine suggested but you must use a drill press with that cutter. I use fly cutters for many things like stepped holes and adaptor bushings they are very handy.

 

[harrysin]

The biggest issue that I've had when drilling small holes in plexi is when the bit is coming though near the end of the cut. Especially when hand drilling the bit can snag and chip on the exit. I like to use stepper bits for that purpose but they probably don't have long enough 'steps' for 3/8 inch.

When drilling holes in acrylics it's essential to have a scrap piece of wood underneath as shown.

 

[CharleyL]

I use Lexan rather than acrylic because it doesn't shatter or break easily. A little bit more expensive, but lasts nearly forever. They make bullet proof windows from Lexan and it comes in many colors, including clear. I can usually get drops up to 1 ft square or sometimes larger at very reasonable prices from my local plastics supplier, because they frequently cut their sheet products to size for their customers, leaving many drops and scraps. Clear is almost always available, but I have ended up with a smoky clear as well.

Charley

 

[harrysin]

I've been very lucky having friends with access to off-cuts of many types, thickness and sizes. Some of the larger sheets were old and removing the protective paper was a chore

 

[swCObob]

I use Lexan rather than acrylic because it doesn't shatter or break easily. A little bit more expensive, but lasts nearly forever. They make bullet proof windows from Lexan and it comes in many colors, including clear. I can usually get drops up to 1 ft square or sometimes larger at very reasonable prices from my local plastics supplier, because they frequently cut their sheet products to size for their customers, leaving many drops and scraps. Clear is almost always available, but I have ended up with a smoky clear as well.

Charley

Thanks, if Lexan is more workable and durable than acrylic this is a valuable suggestion. After reading your reply I did a quick search. It looks like I could have gotten a 12"x24" piece of 3/8" thick Lexan for only 2 or 3 dollars more (Ebay) than the same size piece of acrylic I ordered through Home Depot.

In my rural area the opportunity to find cutoff scraps of either, particularly of a specific size, is very limited. Bob

 

[roxanne562001]

Lexon is way better in my opinion