Our premium Bits & Bits Company *AstraHP Coated* 1/2″ x 2″ LOC Spiral Compression CNC Router Bit is designed for many different applications requiring high feed rates and compression cuts. Compression flute design pulls wood fibers towards the center of your workpiece resulting in crisp clean edges. They work well for double-sided melamine and laminated material. Be sure to see our entire line of 1/2″ router bits!
Note that the overall length is 4″, on most standard 1/2″ routers, this bit protrudes past the router plate about 1/2″.
What is a Compression Bit?
A Compression bit is a spiral bit that combines up cut and down cut action into one bit. The cutting tip pulls the fibers and chips up towards the center of the workpiece. The rest of the bit is cutting and pushing wood fibers down, also towards the center of the workpiece. This up cut down cut action is what leaves a sharp, clean edge on both edges of your workpiece. The up cut flutes on a compression spiral bit is typically equal to the diameter of the bit, for example, a 1/2" diameter has a up cut flute of 1/2". The transition point is referred to as the 'Spiral Change'. We also offer several sizes of compression bit with a shorter up cut flute length which is referred to as a short flute compression (also called a mortise style compression bit). The slow-mo video clip below was shot by none other that Jonathan Katz-Moses and shows the cutting action of the compression bit. You can clearly see the difference between the up and down cut portions of the bit.
How do I use the Compression bit correctly?
In order to properly use a compression bit to get it's full benefit, your initial cut needs to be slightly deeper than the upcut flute length, which as mentioned above is usually equal to the diameter of the bit. When used correctly, you shouldn't see any tear out or chip out on the edges. In the video above, the bit on the left is seen cutting not deep enough to pass the up cut flutes. The bit on the right is set at the correct depth.
Can you use a Compression Bit in a router?
Yes, all of our compression and spiral bits can be used in a CNC, handheld router or a router table.
Philip (verified owner) –
I use mine in a table router, not freehand. Cuts very clean, and given the 1/2″ shank, doesn’t wobble like some 1/4″ bits do. Expensive, but worth the price. Way better than my cheap-o straight edge bits from Amazon and the big box stores.
Mj –
Philip, thanks for taking the time to let us know how it worked for you! Let us know when you’re ready to step up to the flush trim version!
Zach (verified owner) –
Fast shipping, great product. I don’t have a jointer so I used this and a straight edge as a make shift jointer for a table I was building. Hits the pocket book pretty hard but like the other reviewer said, the quality is way nicer than any other router bit out there. Got a perfectly straight edge on 1-1/2” White Oak boards.
Mj –
Thanks for the review Zach!
jlmcneal54 (verified owner) –
What a difference these bits make, smooth cuts with no tear out, glides right through everything I’ve used it on. You will be shocked just how much easier your routing is with these bits.
This was my first try with these bits but have just started replacing all my bits with astra coated ones, the difference is that noticeable .