Bit size for holes

Hardware
1

I am getting started with this and need to know before I buy bits . The size I need for cutting holes.
What size do I use to cut a 1/4 hole in 3/4” plywood?
Thanks

2

1/4" bit should work fine for 1/4" holes

3

Thank you

4

You may get some burn out when using exact sized bits when the depth of material exceeds the depth of the cutting surface on the bit. This is caused by the bit shank rubbing on the wood. So try to get a bit that has cutting height over 3/4".

Up spiral bits will tear out material on top and Down Spiral on bottom. Compression bits (Up/Down) are best for holes where you want clean hole on both sides.

e.g.
Up/Down 1/4" compression bit with 1" cutting height

BTW I have not used this bit and am just giving it as example.

5

Thanks for your help.

6

A word of caution here. Due to the slow movement of the z-axis, drilling a hole with a size-on router bit creates a lot of heat. I had problems with the machine trying to start fires. Babysit the router and keep an extinguisher nearby.

You can also try “pecking” the hole or using a smaller bit and hogging out the hole. Both of these are going to make the operation take much longer.

What I started doing was simply drilling incredibly shallow holes just to mark their locations and then using a hand drill to finish the hole off. This is waaaaay faster and safe than the using the stock z-axis to drill at those kinds of depths.

1 Like
7

Thank you. I thought of doing that. Thanks for your help

8

Make sure you get plunge cutting bits. Many end mills don’t have that ability.

9

Thanks, can you give me an idea of what and where to buy a 3/16" bit?
Thanks again
Rich