Closed Loop Questions

[shermoen]

Let me know if you’d like a few tricks on increasing the diameter of a hole-sawn hole accurately, or drilling acrylic in general!

Please tell about the best method to drill holes in acrylic?

I am an electrician by trade and have had to cut existing holes to larger sizes. But I have not had to do that in acrylic. So what is the trick to do this?

 

[UncommonSense]

Please tell about the best method to drill holes in acrylic?

I am an electrician by trade and have had to cut existing holes to larger sizes. But I have not had to do that in acrylic. So what is the trick to do this?

There are several methods to precisely enlarge a hole in more or less any material a typical hole saw can touch!

Trick #1: use a scrap of plywood or other thinner lumber, drill the desired hole-sawn hole size in said scrap… you now have a hole saw guide! — clamp this drilled scrap over the existing hole, centering the scrap hole over the smaller target hole… now you can drill that target hole larger without using the hole saw’s centering bit! (The scrap with a sized hole in it holds the hole saw centered!)

(^^ bulkhead drilling template/guide combo for my hexagon)


Trick #2: find a hole saw that fits perfectly in existing acrylic hole… find the desired hole size hole saw… use a hole saw arbor with plenty of threads… spin the smaller hole saw onto the same arbor as the larger hole saw! — — this method uses the smaller (current hole size) hole saw as a centering bit, while the target size hole saw cuts precisely!

(^^ 2” [51mm] interior hole saw, 2.375” [60mm] exterior hole saw; for example purposes!)


Bonus tips for acrylic:

— use water cooling as you cut, this process makes a ton of frictional heat! — I just recently drilled over 50 holes in a row with a 1” hole saw in 3/8” thick acrylic; the hole saw wasn’t even warm to the touch because I was just letting a hose trickle a stream of water on my cutting area!

— just like drilling glass; use your drill’s clutch! 12-20lbs before slip seems to work well for reasonably sized hole saws!

— check the hole saw’s teeth regularly during your drilling process for plastic wadding up in the gullet of each tooth; clear all wadded up plastic from teeth before continuing the process!

— drilling a smaller hole right inside the perimeter of your target hole-sawn hole will give all the hole-sawn cut chips of any material being cut a place to evacuate the cut; dramatically improving hole saw performance!

— high speed on the drill can be used for the majority of the hole; just shift to slow/be gentle when punching through the end of the hole-sawn acrylic hole to minimize any risk of chipping/cracking!

 

[shermoen]

Those are many of the same methods I have used! I did assume having to use water as I cut would be very important, otherwise I would think the acrylic would start to melt.

So another question.

Whats the best way to clean dried coraline off of the acrylic?

Without scratching it up too much.

 

[UncommonSense]

Those are many of the same methods I have used! I did assume having to use water as I cut would be very important, otherwise I would think the acrylic would start to melt.

So another question.

Whats the best way to clean dried coraline off of the acrylic?

Without scratching it up too much.

I’ve had great luck here using any old plastic wallet card! Typically an old gift card/etc!

You always want to use a type of plastic scraper less dense than acrylic; polycarbonate is a good example!

You can cut acrylic without water cooling, but it’s a slow process and can lead to breaking the piece you’re working on if the hole saw melts itself to the acrylic completely! — best bet is to just trickle a garden hose/etc on it as you work!