Need to drill thick acrylic, is diamond bit better than hole saw?

[cherubfish pair]

I have an expensive acrylic tank to drill with 3/8" back. I hate drilling acrylic but might try a diamond glass bit on a thick scrap of acrylic first. Anyone do this?

[HippieSmell]

No, I haven't tried a diamond bit, but I think the biggest thing about drilling acrylic is to keep the speed low.

[Gbear]

A normal wood hole saw will result in less melting.
A saw with a pilot drill helps.
Suggest you clamp a piece of wood to the backside to help avoid break through chip out.

[Da Maui life]

Diamond glass bit is not the way go. A wood or even a bi metal hole saw would do the job, slow RPM’s or a squirt bottle filled with water would help heat/melting issues. I would drill the hole undersize then finish with a router and template.

[cherubfish pair]

You say keep speed low, you mean drill speed or pressure on the acrylic?

[Da Maui life]

They both go hand in hand.

Low RPM and low pressure, let the hole saw do the cutting. Acrylic will ball-up and leave globs around the hole if it melts, not to mention mar the inside diameter as well. That’s way I recommended the above ‘I would drill the hole undersize then finish with a router and template.’ you’ll get a nice clean hole that way.

Flush Trim Router Bit like this one

http://www.amazon.com/CMT-806-127-11...outer+trim+bit

[NanoReefWanabe]

3/8's acrylic is not that thick...i would just use a wood bit and have at it...you dont have to drill all that slow either...too slow, like you would to grind glass, will also ball up and melt, as the bit will not be able to clean itself out...a little faster then you would grind glass and a nice sharp (new) wood bit will work just fine...i love the idea of routing the hole afterward...you could also just use a plunge router and bit with the bearing mounted on the top, rather then the bottom, just clamp your template to the top side..

[Timfish]

Like Da Maui life said, go slow and use a spray bottle to keep the acrylic cool. Once it gets warm enough to melt it will gum up the teeth of your hole saw.

[Gandolfe]

A diamond bit is for glass and tile, use a regular hole saw with fine teeth would be best. Drill with normal speed and a spray bottle full of water to keep bit cool. it should only take a few seconds to go through 3/8" thick acrylic. A backing piece of wood or acrylic will make a neater hole. Just use a piece of sand paper to go over hole after you drill it. If there are bigger "chunks" use a razor blade and scrape around the hole to remove any burrs then finish with sandpaper.

[A Reef Scene]

If you drill fast you risk warping the acrylic. At the very least you don't want hot plastic shavings hitting you.

[BeanAnimal]

Carbide tipped hole saws are the best choice. If you douse the area with running water, the shavings will come out whole and there is no chance of the saw getting caught in molten plastic. The water and subsequent reduction of heat will also prevent stress cracking or crazing if the area is to be solvent welded.

[cherubfish pair]

I've drilled acrylic before and the bit will cut for awhile then it gets hot and I slowed my drill speed and let some pressure off. Then it starts to cut again but how to keep from gumming? I've never used water. Sounds like it could make one heck of a difference.

I need a 1-5/8" hole. Should I drill a 1-3/8" hole and use a router from there or maybe a 1-1/4" hole and use a router from there?

What could I use for a template? a scrap of acrylic? Would a 1x dimension scrape wood be too thick?

[Da Maui life]

[QUOTE=cherubfish pair;21841081]I've drilled acrylic before and the bit will cut for awhile then it gets hot and I slowed my drill speed and let some pressure off. Then it starts to cut again but how to keep from gumming? I've never used water. Sounds like it could make one heck of a difference.

I need a 1-5/8" hole. Should I drill a 1-3/8" hole and use a router from there or maybe a 1-1/4" hole and use a router from there?

What could I use for a template? a scrap of acrylic? Would a 1x dimension scrape wood be too thick?[/QUOTE]

Ten ways to skin a cat, I use a ½” MDF drill holes in template to finish size/placement with hole saw. Put some double sided tape to bottom of template if you can’t clamp use a hole saw and drill undersize, leave just a little meat for finishing with router . Make sure you go slow with the router if your using tape.

[kapoorplastics]

Just use a regular battery type drill with a standard spiral bit suitable for wood. Try to keep the drill speed low and take your time when drilling through.

[salty joe]

All these cautions about heat are right on the money. Anytime I drill acrylic, I like to drill a little then cool the hole saw, drill bit, whatever I'm cutting with. I do this beforeI see gummed up molten acrylic.

Gbear's suggestion to use a plywood backer is a good one.

Sharp tools are a must, take your time, it won't take long.

[mcgyvr]

Guys the post is from 4+ years ago..
kapoorplastics is just attempting advertising for their site..

I will alert the mods to have their post removed..

[ericarenee]

Drilling speed depend on the bit you use.. If you use a normal spiral wood bit.. Speed needs to be Fast, Drill very stable no wobbling and No pressure... Running a Drill slow is more likely to cause the Bit to bind and crack the acrylic ....


The key is stability and no wobbling of the drill or bit...Also to keep from having melting I use a shop vac with the hose on the out put to blow away the shavings..