Up Down Compression Spiral Flush Trim Router Bit, 1/4 Inch Shank Solid Carbide Flush Trim Router Bits CNC Spiral Bit with Nano Coating by EANOSIC

I have a triple fluted flush cut 1/4 inch router bit that I usually use in my construction business. I have never used a spiraled flush cut bit, so I thought it might be fun to try out. I used this spiraled flush cut bit it my trim router at first and the bit had no problems cutting 3/4 pine trim boards. However, I did notice that the cut was a little wavy because the trim router has a small base plate so I tried it in my full sized router with a 5ish plate. The cut came out much straighter and I would recommend using a bigger base plate for it unless it doesnt matter if there are a few waves in the cut. It cut through 5/8ths OSB plywood and didnt leave any burrs on the surface. There were some on the bottom of the plywood but I assume that is from the spiral moving downward. I like the fact that the bit is only 1/4 in diameter the whole length and that it doesnt have to take out as much material as my 1/4 fluted bit that is 1/2 at the cutting blades. So far... I really like this bit and am hoping that it stays sharp for a long time so I can use it for many years.

Combination up-down compression spiral trim bits are wonderful for using on material that is laminated top and bottom. It is always best to cut from the laminated surface towards the substrate in order to avoid chipping the laminate. This bit cuts the two services towards the center which is ideal when you want to avoid chipping both sides of your material. I use this for trimming melamine shelves or plywood that has a nice hardwood veneer on both sides. The bit is nicely made and well packaged. I would recommend it not just for CNC but for any edge trimming with a router.

The good thing about this bit, is it is small. I used it with a template with a lot of tight corners and grooves. It did well getting into the small recesses. very little work after wards. Because the shank is 1/4 and the bit is 1/4, there was a little chatter when it was grabbing the grain and would jerk the wood and gouge. I did use very small passes with this, because I had to use smaller passes to prevent the chatter and for safety to of course. If you think about it, a safe pass is less than 1/2 the bit, if not 1/3 and less of the bit. if this is a 1/4 bit, then you should only take 1/16 off on each pass. I think if I was going to use this again, i would use a larger bit to take most of the material, then use this bit to get into the intricate places.

This ball bearing router bit came very sharp and did a great job cutting veneer with minimal chipping or tear out. The ball bearing allows you to precisely follow a template or guide to make perfect, repeatable trims/cuts. My only observation is that for the price, this single bit was a little expensive. Overall though, it performs as advertised and did the job for me.

Having once snapped a premium 3/8 inch spiral on its second use, I’ve managed to suppress any interest in a long, tiny 1/4 inch one. The opportunity to test one through the Vine program overcame a couple of decades of reluctance, and, with less than an hours use, trepidation has transformed to enthusiasm. This is one useful bit. Not surprisingly, it allows me to enter smaller spaces for interior cuts, and to follow more finely detailed templates for external cuts than I could ever hope to achieve with a larger bit. The up/ down spiral does indeed leave a far smoother finish—top, bottom, and in between—than I can achieve with my straight bits. I have used it only for light, slow cuts with the same knowledge “Amazon Customer” shared in his/her January 9th review, which I recommend reading. As others, I still worry the 1/4 bearing is going to hold up. I wish they had included 3-4 replacements with the bit. Time will tell if my concern is warranted, but over that time I’ll be checking often to ensure the bearing rotates smoothly.. I won’t be using this bit often, so it may be some time before I can report on actual bearing life. For now, I can only affirm others in their praise for this bit. It is well worth its modest price,

The 1/4-inch Up Down Compression Spiral Flush Trim Router Bit performed well in my testing. The bit cuts fast and leaves a smooth surface. I tested the bit with 7/8-inch-thick air-dried Cherry wood. The bit performed as described.

This bit is 1/4 from head to toe. So the bearing is also 1/4. Ive never seen one this small. Who knows how long it will last? Ill update if there are any problems. The blue coating and/or the flute design makes this bit cut very clean! For the few materials I tried, there were no blowouts or chads left hanging on top or bottom! I didnt have any kind of chatter or wobbling that I expected. However with the tiny bearing diameter, it will definitely transfer smaller imperfections from your template to the workpiece. More so than with a 1/2 bearing. This is just a lot easier to work with. I think youll have to be careful not to rely on bit color to tell you when youre making too much heat. You wont see discoloration on this coating. I guess youd have already made way too much heat if your bit was bluing. Best to keep your pass speed under control anyway.

As it is an off brand from Amazon, I dont have high hopes for longevity. That being said, for a hobbyist the price is right and it works great so far. Only time will tell on durability.

A spiral flush-trim bit such as this is a somewhat newish design that combines features and benefits of both upcut bits and downcut bits. And flush trim means that this bit is designed to follow a pattern along its bearing, to allow the material above the pattern to be cut flush to that pattern. You don’t want to ask a bit such as this to hog off much material; it’s forte is trimming small amounts smoothly even with sheet goods and areas of changing grain direction. So use your saw to cut close to the line, and this bit to just make that last 1/16” tight to the line and smooth. I can’t say that I have past experience with this company, but this bit does a nice job for a very good price and I would buy one of these again. I’ll update this if the bit seems to not hold up well! I hope this review has been helpful to you!

Hmm, well this has a good cutting edge, seems to make a perfect edge, no wobble in the bit and good longevity. Good buy when compared to the same bit I got from HD at a better price.