SpeTool Compression Router Bits 1/4 Inch Shank 1 Inch Cutting Length with Coated Carbide Spiral Up Down CNC Router Bit End Mills for Carving Wood Woodworking Tools

The key here is understanding what you are buying and how it works.A compression bit attempts to combine the up-cut and down-cut spiral bits, but in doing so it requires a transition point that goes from up-cut to down-cut. This bit transitions at about 3/16" from the tip of the cutter. This means if you only plunge 3/16", or less, you will only engage the up-cut portion, unless you make more passes on both sides at a depth over 3/16", you will not get the benefit of having both on a single bit.Up-cut leaves a cleaner bottom, down-cut a cleaner surface edge. Basically pick where you will risk tear-out or a rougher surface. To get the best of both your initial cut needs to clear 3/16" or else you have to expand it at full depth.If you are looking for a clean face, as in less surface tear out, and won't be going deep on your cuts... this isn't the right bit. Go buy one of their down-cut spiral bits.For the price I decided to give this brand a go over my normal brand that is quite expensive, and so far so good. Early results - 1 project done - are that it is sharp and when used correctly leaves a good surface and bottom.Longevity is always the question with less expensive bits. This isn't a "cheap" bit, per se, but it is in that mid-tier area. I won't know how this truly does for another couple of months, but if it lasts anywhere over half as long as the other bits, at about half the price, it is a win.I normally avoid 1/4" shank bits when I need to plunge a ways down, but no one seems to make a 1/2" shank compression, so 1/4" it is. If they made this with a 1/2" shank I'd pay more for that in a second.I am not sure if these have an actual coating that will extend life by cooling the bit, or if it is cosmetic only, so don't assume the unique colors mean it has a proprietary coating that another brand has. It does look cool, though, lol.So far, so good, and I am considering testing out a downcut of their as well, instead of my normal brand. The price is very alluring, and if their total line is quality then switching over may be worth it.

Cutters are sharp and perform well in my CNC at an attractive price compared to name brands

Excellent cutter. I purchased to use in my CNC machine and could't better satisfied. Smooth and efficient. Definitely recommend.

Pros:Beautiful, crisp cuts with minimal to zero tear out.Seems to be well-made, sharp and durableLong length means I can use it in my router table and with a jig and still get the required depth on my piece with plenty of bit to spare.Cons:Unfortunately, I bought this specifically to use with my box-joint jig, and it cuts slightly wider than 1/2 inch, making it loose on the key. For something that requires a certain level of precision, it’s not great.Overall, I’ll keep it for those cuts that don’t have to be precise, or if I ever need a slightly oversized bit, but unfortunately, the purpose I bought it for, it’s not great.

I will say this might be the best purchase I have ever made for my CNC. I was having squealing issues with other bits, down, up, tried a lot of bits. This is my first compression bit, but it just had a low hum as it cut, and it left a great finish.I am going to try other compression bits as well, but for this price and the great quality cut and most importantly the noise reduction I wasn't expecting. Maybe because its so sharp, the coating looks nice to, maybe that will help with the durability and life of the bit. Its performance for the money cant be beat, especially when it is cheaper than other bits I have used before.

Cuts fast if needed

I didn’t need to make a deep groove, so it lasted a long time. Hard to find 1/16” and I was delighted to find this. My wood could chip easily, so I needed to sand the grooves, but I think that was more a function of my material than the bit.

Apparently not well made at all. Performed well but broke the third time I used it on poplar wood too! Not that hard of wood. Should have lasted much longer. I’ll be ordering from another manufacturer.