Such as bench grinders and belt grinders. The grinding grit thrown downward gets into the sliding mechanisms and causes damage. In the recent training video by Tormek on the BGM-100 use with bench grinders, they commented they don't recommend using the DBS-22 and other jigs. They didn't say why, but the damage I observed is likely part of the reason.
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I had not done any drill bit sharpening for quite a long time. But enough of my bits had become dull that I was getting ready to have a go at it. I've had diamond and CBN wheels for quite a while and had never really used them for drill bits to any great extent. Recently, on another forum, I was exposed to a different style of dedicated drill sharpening, much like the infamous Drill Doctor, but significantly better. I ended up getting one (Vevor) and feel it is a pretty good machine, but I still like the facets and finishes achieved on the Tormek.
So, in messing with all this in past week, I tried setting up the DBS-22 on my Rikon slow speed grinder, using and FVB and USB. This grinder has an 80 grid CBN wheel, which I though would be great for roughing. It is. But the DBS platform and clamping block are very close to the wheel and the grit is cast downward, collecting on the jig parts and getting into the sliding ways, plastic between the platforms and zinc-on-zinc between the clamping block and sliding platform. I noticed significantly greater scratch marks in the grove and ridge of the latter parts.
I have discontinued using the DBS-22 on the Rikon grinder.
As part of all this I was using the CBN and diamond wheels on T8, trying different approaches to roughing and finishing the primary and secondary facets. The nominal method is to grind the primary facets first and then the secondary, the latter requiring a good bit more grinding. I tried roughing the secondary first and then finishing with the primarys. I sort of like this approach and have figured out that the angle of the platform for the secondary facets is about 20º relative to the top horizontal surface of the T8 case - using a digital angle cube.
The angle for primary facets depends on the relief angle used, 7º relief is about 35º and 9º relief is about 32º. I wanted to know these angles so I could go directly to the secondary first. However, even though I know what the relative angles are for 7º and 9º reliefs are, I still use the Tormek angle template for setting these, it is more consistent and faster.
Further messing with roughing first, I decided to see how the "original" Blackstone (SB) would do, as well as the 10" dia. x 1" wide traditional high speed grinding wheel that I fitted to the T8 would do. I found that I like these latter two as much or better than the CBN and diamond wheels. For one thing, there is less fiddling with wheel changes and given how the DBS sets up relative to the grinding wheels, variation in wheel diameter is much less problematic, compared to angle setting for knife sharpening.
I found the grind finish of the SB wheel equal to that of the DF diamond and there is no worry about wearing out the diamond or CBN wheels, allowing them to be saved for knives.
Jumping back to that "other" drill sharpener, the Vevor, I was thinking it might serve as a good roughing first step, reducing the amount of heavy metal removal on the T8. It does, but it creates a single relief angle by rotating the bit, whereas the Tormek creates two flat reliefs in the primary and secondary facets. There is still a good bit of metal removal to do in grinding the secondary relief after roughing on the Vevor. A combination of the two might work, where the the Vevor is used to rough in what will become the secondary and finishing by grinding only the primary on the Tormek. I tried this, it works. But the grind finish of the Vevor (230 grid CBN) is rough enough that it isn't aesthetically pleasing as when the secondary is done with the Tormek. As a result, I'm now wondering about setting up a platform rest on the Rikon for roughing, the way Jan did back in January 2017.
You cannot view this attachment.
Rick
You cannot view this attachment.
I had not done any drill bit sharpening for quite a long time. But enough of my bits had become dull that I was getting ready to have a go at it. I've had diamond and CBN wheels for quite a while and had never really used them for drill bits to any great extent. Recently, on another forum, I was exposed to a different style of dedicated drill sharpening, much like the infamous Drill Doctor, but significantly better. I ended up getting one (Vevor) and feel it is a pretty good machine, but I still like the facets and finishes achieved on the Tormek.
So, in messing with all this in past week, I tried setting up the DBS-22 on my Rikon slow speed grinder, using and FVB and USB. This grinder has an 80 grid CBN wheel, which I though would be great for roughing. It is. But the DBS platform and clamping block are very close to the wheel and the grit is cast downward, collecting on the jig parts and getting into the sliding ways, plastic between the platforms and zinc-on-zinc between the clamping block and sliding platform. I noticed significantly greater scratch marks in the grove and ridge of the latter parts.
I have discontinued using the DBS-22 on the Rikon grinder.
As part of all this I was using the CBN and diamond wheels on T8, trying different approaches to roughing and finishing the primary and secondary facets. The nominal method is to grind the primary facets first and then the secondary, the latter requiring a good bit more grinding. I tried roughing the secondary first and then finishing with the primarys. I sort of like this approach and have figured out that the angle of the platform for the secondary facets is about 20º relative to the top horizontal surface of the T8 case - using a digital angle cube.
The angle for primary facets depends on the relief angle used, 7º relief is about 35º and 9º relief is about 32º. I wanted to know these angles so I could go directly to the secondary first. However, even though I know what the relative angles are for 7º and 9º reliefs are, I still use the Tormek angle template for setting these, it is more consistent and faster.
Further messing with roughing first, I decided to see how the "original" Blackstone (SB) would do, as well as the 10" dia. x 1" wide traditional high speed grinding wheel that I fitted to the T8 would do. I found that I like these latter two as much or better than the CBN and diamond wheels. For one thing, there is less fiddling with wheel changes and given how the DBS sets up relative to the grinding wheels, variation in wheel diameter is much less problematic, compared to angle setting for knife sharpening.
I found the grind finish of the SB wheel equal to that of the DF diamond and there is no worry about wearing out the diamond or CBN wheels, allowing them to be saved for knives.
Jumping back to that "other" drill sharpener, the Vevor, I was thinking it might serve as a good roughing first step, reducing the amount of heavy metal removal on the T8. It does, but it creates a single relief angle by rotating the bit, whereas the Tormek creates two flat reliefs in the primary and secondary facets. There is still a good bit of metal removal to do in grinding the secondary relief after roughing on the Vevor. A combination of the two might work, where the the Vevor is used to rough in what will become the secondary and finishing by grinding only the primary on the Tormek. I tried this, it works. But the grind finish of the Vevor (230 grid CBN) is rough enough that it isn't aesthetically pleasing as when the secondary is done with the Tormek. As a result, I'm now wondering about setting up a platform rest on the Rikon for roughing, the way Jan did back in January 2017.
You cannot view this attachment.
Rick