Drill-bit for Peel-n-seal Roofing material.

[James Evers]

I need to punch a whole through a speaker cabinet composed of a plywood exterior, peel-n-seal constrained damping layer, and a particle board interior. Is there any bit material capable of doing all 3. I have wood bits, but I'm thinking something different is needed because of the aluminum.

[Chris Padilla]

Aluminum is quite soft...all your carbide cutters will cut it just fine...normal drill bits should work just fine.

[Tom Cornish]

Just make sure your regular bit is sharp and that you keep it cutting. Aluminum can melt and stick to your bit if your bit is dull and heat builds up. No matter what - for just a few holes you're going to be fine.

[Jay Jeffery]

Roofing material is pretty hard on cutting tools. I'd use a sharp bit, but not a really nice one.

How big does the hole need to be?

[Chris Jackson]

James...unsure of what bit would be appropriate but I just bought a bunch of Brad Point bits from Bob over at Woodworkers Tool Works (no affiliation). You can find them with a google search. He was very knowledgable of both materials and applications and quick to respond, and best of all the price was right and I could buy my bits one at a time. I understand they run a full machine shop and make many different types of bits for specific applications...hope that helps.

Chris

[hank dekeyser]

Grab a bit and let 'er buck - you didn't say how large the holes are ? If in doubt try a 1/8" bit first to "test the waters" I use aluminum on a lot of stuff - no problem for regular bits. If its 1/16 or thicker you can use rubbing alchohol as a cooling agent. keeps the chips flowing and cools the bit. Curious what kind of speaker cabinet is this ? Anything other than a giant sub seems like overkill on the materials ?? If the damping layer is rubber, it could gum up and give you some trouble. I hate when that happens

[James Evers]

Grab a bit and let 'er buck - you didn't say how large the holes are ? If in doubt try a 1/8" bit first to "test the waters" I use aluminum on a lot of stuff - no problem for regular bits. If its 1/16 or thicker you can use rubbing alchohol as a cooling agent. keeps the chips flowing and cools the bit. Curious what kind of speaker cabinet is this ? Anything other than a giant sub seems like overkill on the materials ?? If the damping layer is rubber, it could gum up and give you some trouble. I hate when that happens

On the contrary the higher the pass band the greater the need for bracing, damping, and stiffness. The Peel-n-seal forms a constraint layer between the layers of wood that reduces the driver-box vibration. Rockwool is used to treat the internal box vibrations and the judicious use of oak bracing raises the frequency at which the box is excited.

http://www.audioholics.com/education/loudspeaker-basics/lowering-mechanical-noise-floor-in-speakers-pt-2 is a good overview if you are interested in further research on the topic. The goal of the project is to complete a reference level 3-way loudspeaker.

[hank dekeyser]

On the contrary the higher the pass band the greater the need for bracing, damping, and stiffness. The Peel-n-seal forms a constraint layer between the layers of wood that reduces the driver-box vibration. Rockwool is used to treat the internal box vibrations and the judicious use of oak bracing raises the frequency at which the box is excited.

http://www.audioholics.com/education/loudspeaker-basics/lowering-mechanical-noise-floor-in-speakers-pt-2 is a good overview if you are interested in further research on the topic. The goal of the project is to complete a reference level 3-way loudspeaker.

Good info- Check out "The Loudspeaker Cookbook" and EV's "PA Bible" I used to work in an Ultra High End shop years back, so I understand what you're doing. Another very deep rabbit hole