As an update: the whole Kinu company is apparently on holiday until September 10th, but Christian was able to get somebody to prepare and send a new drive axle to me from Germany. Arrived yesterday. The axle indeed appears more "finished" and when mounted on the grinder the base of the axle is much closer to "flush" against the bottom of the inner burr.

But.......this axle doesn't fix the problem and indeed makes it worse -- it is still difficult to adjust the grind in a finer direction. The axle (or inner burr) seems to "catch" on the side of its channel when adjusting finer. Sometimes it is very hard to adjust finer (even when I'm out at a full turn from zero) -- other times it is not too hard but I still don't get any "clicks" in this direction. I confirmed again that the inner burr travels smoothly up and down against the spring without the drive axle installed.

I believe I'm experiencing the exact same problem as before -- the drive axle is only contacting the bottom of the inner burr at one point and is therefore pulling up on side, making the inner burr scrape and catch against its axle while traveling up to adjust finer. Though the drive axle appears flush against the bottom of the inner burr -- if I look closely I can see a very teeny tiny gap on one side. And no matter the tiny size of this gap, it has the same effect -- pulling up on one side of the inner burr leading to drag.

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One thing I didn't mention before is that the original M68 that Kinu sent me had two problems (this same problem + the handle would not lock in place due to the set screw not being long enough). Christian sent me a new M68 in two days (from their US shipper in Florida) and a FedEx label to return the faulty grinder. I thought this was fantastic service!-- especially since I'd initially thought I'd be waiting for this grinder to ship from Germany.

But this good service does not make up for a lack of quality control, which appears to be affecting multiple grinders that they've made on this run.

ProCyclist wrote:Nice shots wow. Latest M68 looks like a much cleaner design than the previous version (Stanic's photo with tape measure)

surely you're not going to compare professional product pictures of a new unit with coated burrs, with a phone snap of a used one

Securing the M68 to the worktop with bench dogs by Orphan Espresso

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