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 couple of bits from this company, and I’m impressed with the quality. This particular 1/4” bottom bearing flush cut bit is a useful size for following tight patterns or for trimming flush to another piece. You do need to make sure your pattern is accurate and smooth as any imperfections will show, given the small bearing diameter. I’d consider this a tool for precision work, rather than hogging out the edges of countertops- solid carbide is not for forcing, and the 1/4” diameter means you need to take it slow. If you have never experienced the improved quality of cut from a good spiral ground router bit, you should give this a try.

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.

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,

This bit is only used to produce repeatable results using a pattern attached to the workpiece as a guide. A bearing is used to follow the pattern and neither the process or this type of router bit are anything new. What sets this bit apart is that it cutting edges are slightly angled to slice both up and down. This results in a shearing cut rather than a chipping cut and should produce a smooth cut with little or no chip-out - well see. This is also a small diameter bit. Itll get into tighter areas, but its small size requires a bit more time and patience. You cant force this bit because its cutting tip speed is much slower than a bit of larger diameter. Both rotate at the same RPM, but the larger bit has to move faster around a larger circumstance. This little bit has the potential to produce edges ready for finish, but you cant rush it. Its also important to rough-cut work pieces very close to their finished size because you cant hog material with bits as small as this. This bit is for the last 1/8 give or take, youre not going to plow with it, at least not very far before it breaks from heat buildup. Use it as intended and with care and it shouldnt disappoint.

This is my first experience with an up down compression spiral flush bit. It did not disappoint. So far, I’ve only used it in testing and one small project, but the results have been very encouraging. Plywood trims were clean with no significant chipping. Softwoods like fir and cedar trimmed clean and smooth. I used it with my trim router and, as another reviewer has stated, a larger base would be helpful. I did get a few waves but that was entirely due to my too-casual technique at the time. Key unresolved issue is longevity of the product. So far I’ve seen no red flags in that regard and expect this bit to serve my purposes for many years to come. If that should change, I will update my review.

Bit works great, stays sharp

This is a very interesting take on a compression spiral bit, one Ive not seen before. Its not what you would typically expect from a compression spiral, with upward and downward flutes meeting at roughly the center of the cutting area. Instead, its more like a down-spiral bit, with a pair of shearing rakers like a Freud Quadracut bit at the tip end. I wouldnt want to use it for something you need a real compression spiral to get the best performance out of, but this has performed very nicely for me in the little bit of testing I have done so far. It was able to make nice, clean pattern cuts in walnut, oak, and pine with no fuzzing or tearout. The bit comes razor sharp, as youd expect from a spiral, and so far has held up well. I will be really interesting to see how it holds up longer term, but at least in the short term it has held and cut very nicely.

Sharp and leave a good top and bottom finish. I have had no problems with bits from this company. easy to use.

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!

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.