Greg, is that a shadow in the grind port? or is that grounds sticking in there? hard to tell...

They're grounds. You can see some more over on the opposite side - it was a while back when I took this picture, but I think I had just removed the cover and the top burr right before taking the picture. So most likely some grounds fell out of the top burr when I was removing it - they wouldn't be there under normal use.

The tiny bit of grounds in the exit port probably _would_ be there in normal use - but it's a tiny fraction of a gram.

Thanks for that, Greg. Your picture has inspired me! I'm scheming away again.... but I'm at work right now and no access to my k10. Boy am I loving this week! its really the first full week that I've had with this wonderful grinder, the other times I've used it, it was only to grind a shot and then off to the garage to modify it. Man it is a wonderful grind... very flavorful, and fluffy! No more WDT... I simply bang the pf sideways until its more or less even, then tamp the corners in.

Does anyone know the internal diameter of the grind chamber on the k10 offhand? I need to order some delrin for it... I'm pretty sure the 3 paddles are not pushing the grounds out fast enough, it needs more paddles/fingers. Also, the stock paddle fit leaves a lot to be desired... there is a considerable gap between the end of the paddle and the wall of the grind chamber, so grounds get pushed out to the wall and can hang up there, and slowly work their way around to the opening sometimes... I thought about 'capping' the ends of the arms with Velcro, but the Velcro i'm using is adhesive backed and I didn't want to risk trapping a piece of Velcro that was slowly coming undone, against the wall and exit port.

OK, I wanted to use it for a week before taking it apart, but I'm getting antsy and I need those dimensions anyway to see what machining stock I have to order for my next step in this evolution... so I pulled it apart tonight, I'm a few days short of a week now; this is what I found on the inside (I have been using the brush to sweep the opening, but NO USE of the blower at all (not needed):
Outer burr appears normal:

Grind chamber and inner burr:

That is not coffee grounds sticking to the paddle... its the velcro coming out.
detail of one of the paddles:

So, the short answer is yes, the velcro allows use of the stock paddles to sweep out the chamber VERY well, indeed; nearly retention-free. The taste of the singles has been AWESOME, I am really happy with this grinder. However, as can be seen in the last pic, the velcro tabs are slowly migrating. The paddle 'spider' is being pushed down and the velcro rubs with considerable drag against the chamber floor... I noted this earlier when I noticed the grinder stops quickly when you shut off power to it. Since the drag is applied in only one direction, the glue holding the velcro is acting like a super cooled liquid and the velcro is slowly oozing out from under the paddle.
So, this can be rectified, I suppose... get another kind of velcro and use a permanent silicon glue? or cyanoacrylate or epoxy. Or simply just torque the middle burr screw a little less during re-assembly and experiment with less tension on the burr. Or, the simplest way to fix this would be to just shave away the underside of the paddle slightly to provide a little more clearance height so the velcro doesn't scrape as hard. Or put a very thin washer under the center of the bearing ring to lift the whole spider up slightly. But, I'm not that happy with the k10's stock spider anyway. Time for something better. By the way, I've named my mazzer the frankenjolly, so of course the k10 must be named the frankenpak. I've also decided to name my Rancilio Rocky the frankencilio. Talk about family with a checkered history!

Walt, do you know if the adhesive holding that felt is food safe? You're likely ingesting small amounts of it.

Hi Tom, nope, have no idea... maybe that's why the shots have been tasting so good!
its so sticky, I doubt it will come apart and go into the grind like that, though, and the amount is tiny anyway. Although the velcro works excellent (aside from slowly moving out from where its supposed to be), I will just replace the spider/velcro at this point with something better. The trick is to get a good sweep of the floor while still retaining adequate capture of the inner burr, its sandwiched between the spider and top nut... so the spider, which is now aluminum, probably needs to have fingers made of something lightly compliant, like delrin, to accommodate slight changes in the floor contour but still sweep it clean. I was playing with the idea of making it a hybid; main body of aluminum mated to delrin fingers, but its easier to just make a new spider out of delrin entirely, I think. Don't have any in that size, have to order some.

OK, the aluminum stock and delrin stock I ordered has come in. Will post pics tonight when I get home... took apart the K10 top turret and its 155mm main gun and... oh, wait, wrong post. sorry!

anyway, had a few designs in my head come and go, the machining quality and tolerances of the pieces I found in the top turret were BEAUTIFUL and I am reluctant to trash some of these parts. So... question to the group; has ANYONE tried to use the K10 without tightening down the little pogo stick tensioner? The turret seems pretty tight and not really prone to move.... I found a wave washer inside the turret that tensions the outer burr carrier, so it stays still while you rotate the turret to adjust grind size; I was going to chuck all of that and build up the bottom, but when measuring the center spindle, found a (small) bit of misalignment. Its not exactly in the center of the grind chamber, which complicates things a little (for one thing, it will affect the sweep of the new delrin spider). Now I am more partial to keeping some of the original elements as it makes the turret/outer burr carrier 'floating' so the outer burr will center on the spindle, within reason. So again, the question is; has anyone just ignored the tensioner in the turret and just ground without tightening it down? has it ever moved under grind pressure?

walt_in_hawaii wrote: So again, the question is; has anyone just ignored the tensioner in the turret and just ground without tightening it down? has it ever moved under grind pressure?

I just backed off the tensioner & ran 18g through my K10. The cover didn't move at all.

Neither of the K10's I've used needed to have the collar locked to hold grind setting.

I feel like threads of this nature create an irrational perception. In this case, the K10 is a wonderfully simple grinder considering it's commercial pedigree & size. The latest model PB I have is a piece of cake to use for single dosing w/o any mods. Essentially no retention with a little brushing of the chute & pulsing of the grinder to clear the chamber. I've seen several folks modify these commercial doser grinders to doserless & IMHO the doser is a handy tool. Since these large commercial units need a little assistance to move all the coffee through (pulsing/chute brushing) the doser is a fantastic catch receptacle. Once you've cleared all the coffee - you just give a few thwacks to fill the PortaFilter. This process actually has a hidden bonus of allowing you to evenly distribute the coffee & break up any type clumps or static. No RDT required period in this style of grinder.

jammin wrote: This process actually has a hidden bonus of allowing you to evenly distribute the coffee & break up any type clumps or static. No RDT required period in this style of grinder.

That's been my experience also.