End mill for 3/4" Plywood

Hello everyone,

I’m looking for a good end mill I can use for cutting pockets, holes, and perimeters in 3/4" birch plywood. I’m debating between the 1/8" straight cut available here on inventables or a 1/4" down-cut. I’m having some trouble finding bits that have the proper length for 3/4" ply.

Looking for good value as I’m a beginner.

Any and all info or recommendations are welcome. Thanks!

A lesson I wish I had learned earlier … be very certain to use downcut bits for plywood.

The Inventables ones are good and fairly priced, I think. An ebay seller named drillman1 offers a huge range of bits with great service and good prices if you need something longer.

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Unfortunately, both down-cut bits on inventables and drillman1 only have a cutting depth of 17 mm or ~0.69", not the 0.75" I need. Do you know of any other places I could look?

It would take some testing but you could do 1 pass with a downcut to go a quarter inch down and then finish with the longer bit. That may alleviate the tear out issue.

Not a bad idea! Probably will need to tool change in most projects anyways. Do you have any experience with 1/4" bits? any cutting performance difference? I have the standard dewalt 611 on 1000mm

No, not much. I’m sure someone will be by with some learned advice.

I get my 1/8" down cut bits from Inventables and cut thru 3/4" material all the time. Also keep in mind plywood is ussually not 3/4".

I checked my 3/4 ply and sure enough one board is .703 inches and the other is .733. The neon yellow, 1/8" down cut from inventables is working great for me. Thanks for the suggestion.

Bonus: I learned the hard way you need a waste sheet directly under your cut or it will blow out the bottom of the plywood. a 1/2" sheet of mdf has been working well for me.

This looks like an older thread but I’ll throw my two cents in here anyway. An up cutting bit will clear chips easier, but is not a good choice for plywood as it will tend to tear out the thin veneer coating. A down cutting bit is a better choice, but is also forcing the chips “down” into the work, and you can actually start a fire (quite literally) drilling out holes with a down cutting bit, so be careful.

What I found does a very nice job is a two flute bit. I’m especially fond of the Amana 2 flute as it allows plunging. Not all two flute bits have the cutters going to the center or even if they do the cutters tend to be flat or straight. This is not good for plunging. You need a cutter that is slightly angled, so the outside edges hit first, and then the rest of the cutter clears the chips kind of like a drill bit.

Lastly, better software will allow you to “ramp” into the work which makes it easier for the bit to plunge into the work. This is not possible with 2.5D work or what most other people call 3D work. The amana cutter mentioned is $15 or so vs $30 or so for a downcut bit.

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Thanks for your input Troy! Is it the 1/4" Amana 2 flute? I’ve never used a 1/4" bit so I’m curious if there is any performance advantages.

Here’s a link to the bit used. This is one of my favorites so far.

I use standard upcut spiral 1/4" router bits for 99% of my jobs. And I can buy them locally. I haven’t really had tear out issues to speak of, as long as they are sharp

If you live in a really dry climate or have a really dry shop, veneers can become extremely brittle and chip. I agree that a sharp bit helps, but IMO you’ll have less problems with tear out overall if you use a down cutting bit or one of the two flutes bits mentioned.

Here’s a nice video that compares an upcut, downcut, straight bit, and up/down end mill.