SpeTool Carbide O Flute Spiral Router Bit 1/8 Inch Cutting Diameter 1/4 Inch Shank with Coating Acrylic Non-Ferrous Metal CNC Milling Cutter

This bit has been great for cutting HDPE. It's super sharp and leaves a great finish on the top and bottom. I only do .25 deep passes, (I don't want to stress anything), but it is a work horse for sure.

I am amazed at how well these bits cut. We recently started cutting thin aluminum sheets on our CNC router (0.025 inches thick). We were having issues with our expensive, name-brand uncoated carbide bits loading up with aluminum and destroying the cut edges of the parts. I did a bit of research and came across mention of TAC coated bits being the best for aluminum. I decided to order one of Spetool's TAC coated 1/4 inch O flute upcut bits to test out. This bit has blown me away. I have never used a bit before that goes through aluminum so easily and cleanly. I have cut hundreds of feet of .025" anodized aluminum with the same bit, as well as some 3/4" MDF. It is still razor sharp with no visible wear on the edge or the coating. I am cutting it on a vacuum table, with no coolant and no air blast. I can grab the bit immediately after cutting up a sheet and the bit is cool to the touch. The large o-shaped flute never clogs and the surface of the bit is so smooth and slippery that not even painter's tape will stick to it when I run through a strip of it.I am running the 1/4 inch bit at 15,000 RPM and feeding at 60 inches per minute, step cutting parts out in two equal passes and have had no issues whatsoever. I'm sure it can go faster, but I did not want to push it on a project close to deadline. Oh, and it's about a third of the price of the bits we normally buy. Buy this bit. You will be happy that you did.

very impressive tool bit. Managed 1/4 inch cuts with out breaking.

Got this for HDPE milling, works great, have 10 hours into this bit and still cutting like new.

These should probably just be used on plastics. I broke 3 of them in the process of cutting some soft aluminum. Not quite sure why they broke, the temperature was low through the cutting process and the speeds and feeds were set correctly for the material and size of bit. I have been successful in the past, but these bits didn't make the cut!

Purchased to make edge lit acrylic signs. Cuts well and leaves a nice finish on the edge walls. There are better bits, but for the price these will do well for my use case (18000 rpm. 100 ipm, xy feed, 30 ipm. plunge.Quick delivery on Amazon (got to love prime).

Sharp and as advertised

Bought this for a spare just to have on hand. The first one is still cutting well.