Honing Carbide Cutters

[jttheclockman]

Somewhere in one of the recent posts someone asked how to hone carbide cutters. I could not find that post again so thought i would pass this info on. I recently was at a woodworking show and bought a Trend Diamond honing kit. I got this through a recomendation from a well known turner on another site. I saw the demo at the show and was very impressed. I brought the kit home and tried it on some old cutters and it worked very well.

I used the credit card stone with the trend cutting oil and a couple of quick figured8's on the flat side of the cutter is all it took. I will use the other stones in the kit to sharpen some saw blades as well. Also some router bits and fostner bits. Money well spent. I have found that not all dimond hones are the same. These are abit pricey but will last a long long time. As they say you get what you pay for.

http://www.woodturnerscatalog.com/docs/trend_diamond_sharpening.pdf

 

[Joey-Nieves]

That was me. There a video from fool4 peppers but what I do is I use a Block from Harbor Freights that has 200,300,400 and 600 grit diamonds for about $9.99.
I rub the insert, face down about 6 time on the 600 grit, if it's in bad shape i rub it on all 4 sides. just put it face down and move it in a circular motion about 6 times.
Remember this is a diamond file that can be very aggressive, even at 600 grit. Also diamond files are only for carbide, HSS reacts to the diamond and neutralizes the file rendering it useless.
CBN wheels on the other hand are made for HSS and are worth every penny but they will not work on Carbide, they also react and are ruined by the carbide.

Joey

 

[jttheclockman]

That was me. There a video from fool4 peppers but what I do is I use a Block from Harbor Freights that has 200,300,400 and 600 grit diamonds for about $9.99.
I rub the insert, face down about 6 time on the 600 grit, if it's in bad shape i rub it on all 4 sides. just put it face down and move it in a circular motion about 6 times.
Remember this is a diamond file that can be very aggressive, even at 600 grit. Also diamond files are only for carbide, HSS reacts to the diamond and neutralizes the file rendering it useless.
CBN wheels on the other hand are made for HSS and are worth every penny but they will not work on Carbide, they also react and are ruined by the carbide.

Joey

Joey you may want to read the info in that link I posted. Diamond hones can be used on HSS also. Not sure where you got that info. I have been using diamond hones on my turning tools for some time now. The key is to use a lubricant and clean the hone. That is why they supply an eraser in the kit that I mentioned. HF hones are cheap and break down very fast. To me not worth the money. Also probably not very flat to start with.

 

[Joey-Nieves]

According to Norton Diamond and CBN http://www.nortonindustrial.com/upl...og_PDFs/NortonCatalog-DiamondCBN-Products.pdf page 6 on the PDF, page 263 of there catalog, and Also while attending a seminar at Craft USA, Kirk Dehier also stressed the point, if you also access different forums you will also find more information on this.
It is basically the combination of heat and carbon that reacts with the diamond and dissolves it.
I supposed that this is one of those technical issues that falls under the category "if it works".

 

[monophoto]

Obviously, this is a complex subject. But my brief search of applicable information indicates that the sky is not falling, and this does not bode the end of the world as we know it. Ultimately, the issue hinges on whether we are talking about a manual honing operation, or a powered machining operation.

One of the significant differences between CBN and diamond is that the diamond molecule has a couple of electrons that are less tightly bound. The presence of those electrons means that diamond 'graphitizes' at high temperatures. The temperatures required to cause this reaction are very high, but the presence of iron can lower the temperature at which the reaction takes place (to as low as around 700-800 degC). Once a diamond crystal graphitizes, it becomes soft and will fail mechanically.

I suspect that for most woodturners, diamond hones are used to manually sharpen tools, and when diamond hones are used manually, it would be almost impossible to achieve a temperature much higher than room temperature, much less high enough to fail diamonds. So I don't think there is a problem with manually sharpening a chisel, drill bit or other tool.

On the other hand, using a diamond abrasive in a powered machining operation certainly could lead to higher temperatures that could cause failure of the abrasive.

 

[jttheclockman]

This all maybe true and way above my pay grade. All I can say for what we do Diamond hones are readily used and work just fine. Yes they are hand held. No need for power. As i said though there are different diamond stones and the way the diamonds are attached and what type diamond stones are used. use the link that I provided in anyway you see fit. Just wanted to supply a little info.

 

[Joey-Nieves]

thanks