3PCS Carbide Engraving V Groove Cutting Bit 2 Flute Straig 6mm Shank 0.5mm Tip 15 Degree CNC Router Tool Blade for Steel Brass MDF Wood

I wanted to share my experience with this bit and give some details that differ some from the other reviews posted here. I use this bit in a CNC router.Firstly, this is a metric bit. The shank is 6mm in diameter.This will NOT safely secure in a 1/4 inch collet. You must use a 6mm collet on your router or spindle.There are some bad reviews listed here complaining that the bit did not fit well in thier 1/4 inch collet, and that is the reason why!!The description states that it can be used for steel and brass, but I don't think that is accurate.The bit angles down to a .3mm tip and I doubt very seriously that the thin tip can withstand cutting into any type of metal.I use mine to cut wood, specifically hardwoods, and it performs beautifully.Though a word of caution, you can't push this bit hard due to the thin tip.It will break very easily, so your feed rate needs to be slow.I broke the first couple of bits that I bought, but once I found the proper feeds and speeds, I have not broken a bit in a very long time, and I have put several miles on it.It is very sharp and the geometry seems to match the product description, though admittedly I have no way of measuring it accurately.This has become my go-to bit for engraving fine detail, and it seems to be the only bit that I have found that possesses the shallow angle (15degree) as well as the small tip diameter.If you need a narrow bit for super fine detail, I don't think that you can get any better than this.

I've been Benn running my CNC business for 6 years and decided to try a new brand. The shank is not .25" but actually .2335". I figured it was a random error so I tried the next one then the last one (bought a 3 pack). All the same within .005" of the first one. Way outside normal machining tolerance errors and apparently they have terrible quality control. Even with my collet fully tight, the bit falls out freely. Initiating refund now.

I use these bits for doing inlay work on my CNC. I used Amana bits before I found these. Much better than Amana and much less expensive. Great for the deeper inlays needed on end grain cutting boards.

Broke the very tip off the first bit quite early. Actually was almost sharpened to a point less than 0.3 mm. The shank size is listed at 6mm. By actual measurement was 5.94mm. This meant that my 1/4" collet was clamped down pretty good and did not release properly because it was sprung a little from clamping on this bit. That is a caution that you might consider if using a 1/4" router. I used a diamond file to flatten (shorten) the one with the broken tip, and it is now around 0.5mm, and still works great.

As a concrete sculpture artist this are perfect for cutting the castings

The quality looked decent but I had to return these because like most I don't have a 6mm collet for my router

The description claims this is will fit a 1/4 shank. That is a not true. Will just fall out. I bought these to do inlay cravings. I can't use them. This was for a wedding gift and had a limited time to make it. Thanks to the false description I was unable to make the inlayed cutting board for the wedding. Do not buy. False description.

Works in a chuck but not a 1/4” router, to small.