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Need diamond file recommendation

magneticanomaly

Titanium
Joined
Mar 22, 2007
Location
On Elk Mountain, West Virginia, USA
There are lots of diamond files on the market. Many are single-layer diamond grit captured in electroplated nickel, some look like diamond grit mixed with metal and then sintered, or anyway seem to have a much thicker abrasive depth. Some have holes to look bigger with less material

I want a few simple files with which I can file or touch up carbide by hand. Form factor like an ordinary 6" or 8" flat file would be fine. I do not want one with holes, because small or pointy workpieces would foul the holes and get blunted. I have no experience with diamonds so I do not sure what grits I need a) to file .010" off a 1/8" x 1/4" carbide tip in reasonable time, then b) to get a durable cutting edge

Of course I want e-bay price and De Beers quality. How close can I get? Who has bought some and been happy? Fool's errand?
 
Explain more on touch up carbide by hand and what is reasonable time. (or not)
Most plated files are way to course for this work.
Resin bond diamond grinding wheels are cheap on e-yuck.
Smash one with a hammer and you have broken sections that make great diamond files.
.010 in carbide is a lot to do by hand filing but will .002 off the top and .002 off the front do the trick? Much easier than trying to take the wear land top work only.
Ten thou off the top by hand will need to start with a serious grit and work your way down in grit or the edge will be poop.
Bad picture but below some sections that came out or wheel wrecks. One a 120 the other a 400, not on purpose but useful.
Use some water, not dry. All finish strokes need to be into the cutting edge keeping the carbide in compression.
I do not think you will like doing doing this very often and HF bench grinders are cheap. Slower speed better.
Bob
 

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I have a nice cheap set of Chinese files from the early 90s that I still use, around 100 grit. That said you REALLY want your diamonds spinning fast in disc form for both speed of cut and quality of surface left. I have 5" resin bond disks stuck to the end of a 4000 rpm dc motor with a speed control, leftover from a previous job but very handy.
 
I have a set of Eze-lap files. I use them for just exactly what you intend. They vary from fairly coarse to very fine. I will use them to quickly refresh a cutting edge on brazed carbide tools. I’ll use a medium one if the edge needs a bit more removal but finish with the green which produces a very shiny mirror edge that is very sharp. I also use them on brand new square-end end mills to just ease the dead sharp corners. With the end mill in a vise and using an illuminated magnifier, that takes only a minute or two but makes the cutter much less prone to chip. Same for brazed carbide—-after sharpening them on my SG diamond wheel I put whatever radius is needed on the nose and , depending on the material being cut and precision needed, may put the mirror on the flats. One set has lasted me a decade.

EZE-LAP L PAK5 Set SF/F/M/C/XC Color Coded Diamond Hones - Sharpening Stones - Amazon.com

They are diamond grit nickel plated onto steel shims.

They come in handy for a lot of other tasks as well.

I also have a set of the coarse and fairly crappy red-handled Chinese diamond needle files. They would be way too coarse for sharpening cutting tools, but find an occasional task.

Denis
 
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I have a set of Eze-lap files. I use them just them for exactly what you intend. They vary from fairly coarse to very fine. I will use them to quickly refresh a cutting edge on brazed carbide tools. I’ll use a medium one if the edge needs a bit more removal but finish with the green which produces a very shiny mirror edge that is very sharp. I also use them on brand new square-end end mills to just ease the dead sharp corners. With the end mill in a vise and using an illuminated magnifier, that takes only a minute or two but makes the cutter much less prone to chip. Same for brazed carbide—-after sharpening them on my SG diamond wheel I put whatever radius is needed on the nose and , depending on the material being cut and precision needed, may put the mirror on the flats. One set has lasted me a decade.

EZE-LAP L PAK5 Set SF/F/M/C/XC Color Coded Diamond Hones - Sharpening Stones - Amazon.com
...Denis

These are good for what you want to do.
A bit cheaper to buy them individually in just the few individual grits you need. One maker of these on plastic paddles is Foredom (the drill company) and they can be bought cheaply from, among other suppliers, PRECISION SCALE MODEL ENGINEERING

-Marty-
 
I find diamond needle file really useful for refining hand ground hss form tools. Removes material much faster than anything else. And my understanding is that at very low speed there is no problem using diamond on steel. Mine are a set from ebay 20yrs ago. Originally bought them to use on mother of pearl.
 
I just steal the diamond finger nail files from my wife. They are basically disposable and will do a pretty good job on carbide. When they get dull I just steal more from her. She still hasn't figured out where they disappear to.
 
A thing to keep in mindis what CB mentioned above, the grit.

You can put a radius of x with your 200 grit file, and watch how it breaks down in _a_ cut, much less several. For a lot of turuning the burnished final radius is ok. But for a lot of other stuff not so much.

My standard Agathon grinder is rough (100, 150 micron?) then fine, 14MD or around there, I finish by hand on a worn 7micron wheel to approach mirror finish. Makes a big difference in tool life and finish. Before I got my beloved D7 wheels I'd finish on a copper wheel charged with 3 micron diamond paste. A D7 with 10 minutes on it cuts like a copper lap witb 3 micron paste or better!
 
I have a few vallerobe needle files, they are really quite good, I beleive they do different grits or mesh, mine were a mix from a flea market, I found the Chinese ones get bald, eze Lapp are known for reasonable quality though as mentioned,
Mark
 
I have used the Eze-Lap diamond paddles for 20 years, they work great for general use. Finish lapping a tool could use a finer grit for longer life, but at that point you might as well go to a powered grinder/lap.
 
Just for clarity, the EzeLap set ranges from 150 to 1200 diamond grit size. I do have a diamond lapping setup that I can charge down to .5 micron diamond paste, But, the 1200 provides a very shiny surface that seems very durable and is sharp enough for most of the lathe work I do.

Many years ago, when I first started working with my lathe, a friend recommended I get brazed bits at Harbor Freight. At least I thought he was a friend. He was a very experienced machinist and millwright at a local aluminum smelter, so, I took him at his word. That advice set me back several months on the learning curve as I now know those bits that are advertised as “sharp” are anything but. Eventually I ended up buying some brand-name inserts and life got better. But I have also learned that, in general, the HF and Big Bear brazed inserts will work quite well if I put an edge on them with my diamond wheel on the SG and put a little nose on them with the files. The fine file provides an easy way to quickly refresh an edge. Works (well) for me.

Denis
 
Another happy Eze-Lap user. Buy a couple each of the Fine and Medium, maybe one of the Very Fine. Skip the coarser ones, they are a lot like trying to sharpen your pocketknife on road gravel.

Hit up YouTube and search out 'low speed carbide grinder', for some examples of how to make a decent operating rig on the cheap.
 








 
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