We have a good relationship with MK...if enough are interested I'd be game for managing a group buy (mods, I hope this is OK, for the last MK group purchase I acted as facilitator and it was profit-free save for the collective discount)

i'd be down, depending on price

Folks interested PM me and CC Russell. Leave this thread on topic of the grinder itself. Further sales posts will be removed.


EDIT: Don't ask me about discount prices, I don't have any inside information yet. I'm just offering to organize an interest list and I want to keep it off the thread since it's off topic.

boar_d_laze wrote:Some Ditting/Mahlkonig cast burrs can be resharpened; but I don't think any of the forged ones can. Like I said though, I don't really know.

Rich

From earlier video we learned about materials, so I'm not going to that.
I guess, burrs being resharpenable or not depends burrs cutters shape. MK Peak burrs looks like they are easy to resharpen. But burrs like in picture are much harder to dialing in to grinding machine. I don't say its impossible. Maybe someone knows better.

Both Bunn & Ditting will resharpen their cast burrs up to 3(?) times. I've never seem any company offer to sharpen one of their machined burrs.

JohnB. wrote:Both Bunn & Ditting will resharpen their cast burrs up to 3(?) times. I've never seen any company offer to sharpen one of their machined burrs.

If I was guessing, I'd suggest that's because they can make machined burrs at the minimum size and cast burrs either start out thicker or they have less detail so more room for resharpening. There is no reason machined burrs could not be resharpened if they were designed for that.

Ira

This is nothing more than speculation on my part since I haven't seen a process sheet, but in regards to their fully machined burrs I would wager they are getting their final hardness using a gas nitride or ion process just prior to final grind. That kind of process has a rather shallow case depth and resharpening would likely blow through it.

With the cast burrs they can heat treat to a much higher hardness to start with since they are just surface grinding the tops off. With the burrs machined from rod stock they have to go through machining processes so they have to start with somewhat softer material and get that final hardness later on or else their tooling costs would be astronomical. Once you get steel as hard as they are in their final processes, the only steps left you can do are really grinding and EDM (and to a limited extent hard mill.) Any machining operations need to be performed prior to final hardness. The process used to get that final hardness will alter dimensions, so grind is usually the final step with the exception of exotic coatings.

Again, without a process sheet, it is just guessing. There are many many ways to make the same part. This is very similar to gear cutting / gear grinding. There's lots of youtube vids for that. Not too many vids for coffee burrs!

Mahlkoenig's coffee grinder technology and craftsmanship

http://gcrmag.com/marketing/view/mahlko ... ftsmanship

Shife wrote:This is nothing more than speculation on my part since I haven't seen a process sheet, but in regards to their fully machined burrs I would wager they are getting their final hardness using a gas nitride or ion process just prior to final grind. That kind of process has a rather shallow case depth and resharpening would likely blow through it.

Again, without a process sheet, it is just guessing.

Might be just guessing, but it sure sounds like a better guess than mine, didn't even think of that.

Ira

Beenbag wrote:There is a Utube vid of a tour of the Mahlkonig factory...

Very cool video...and what a mullet at 5:15. Billy Ray would be envious.