(note: Kludge Grinder v2 with a new easy hold grinder base is documented on post #13.
No longer do I need a strap and drill to grind with the Kludge!
K Grinder: a homemade 68mm - titan - conical grinder experiment)

It's called a K Grinder for Kludge Grinder:
kludge
noun 1. an ill-assorted collection of parts assembled to fulfill a particular purpose.
verb 1. use ill-assorted parts to make (something).

I've been wanting to play with titan class, conical burrs for a while. I was able to get some old Compak K10, used, test burrs from an HB member for this project. The test burrs still have some life left in them too! (Thanks to Terranova for those old burrs! )

The burrs I received are the K10 style that doesn't have the keyway. I think that's the K10 Fresh burrs, but I'm not sure. I was concerned about mounting the center burr on a shaft so it would not turn, but a good solid friction mount worked just fine and the burrs are solid.

For a test grinder I got the following parts:
3" drain pipe PVC
3" PVC straight junction
3" PVC drain cap, insert
3" PVC end cap, cover

3/8" carriage bolt
3/8" nylon lock nuts
3/8" nuts
3/8" fender washer
#6 bolts & nylon lock nuts for outer burr mount
#4 screws to hold drain cap & outer burr assembly

I wanted to hand crank this beast, but it's just not solid enough to do that. A cordless drill and a jar strap take care of the grinding bracing. Load it up with a water bottle funnel. Grind into a small cooking ingredient cup placed under the grinder and I get the most beautiful grind and pulls.

So test was completed, but I thought I'd share the construction in case anyone else wants to make one in a pinch.
"Grinder Set"

Showing height of grinder:

Bottom of grinder:

Here's a breakdown of the main grinder body:

Another breakdown showing the drain insert with plastic grate cut out:

As stated above, this was a work to test my spindle mount idea on the K10 burrs. Not a permanent design, but just a proof of concept. Burrs are 68mm OD.

The bore of the center burr is 7/16". I used a 3/8" carriage bolt for the spindle. Mounted the bolt in a drill press and used a file to shape the under head square block to be angular and tapering toward the bolt shaft. This centers the base of the burr on the bolt.

For the top of the burr I mounted a locknut on a 3/8" shaft in drill press and used a file to change the flat bottom of the nut into a taper here too.

Slipped the burr on the shaft, tighten up the locknut, give it a spin and all should look centered. Torque down the locknut, and then added another nut, locking against the locknut. This combination seems to keep the burrs firmly locked into place.

The outer burr dropped right into the drain insert, so a couple of bolts with locknuts and a hot knife to cut out the unnecessary grate took care of the "burr mount". Slipped that into the 3" drain pipe and used 3 small screws from the outside to hold the drain insert in place.

Flange washer was drilled out to 1/2" and a 3/8" ID bushing was placed in there and through a matching hole in the PVC end cap. A second larger hold was drilled in the end cap for loading the grinder.

Single locknut on the shaft is enough to keep the grind adjustment set. 2 more locknuts locked against each other are the turning point for the socket on the cordless drill.

For setting the grind you just follow procedures similar to the Pharos. This unit is constructed of PVC plastic, so the give inherent in that plastic does cause a little issue dialing in the grind, but once it's dialed in everything is great. I've been using it for shots all weekend long, and have been very happy with the results.

Now time to tear it down and move on to the next stage!

Great job! The pharos was really a launching point for me as well. Mod it a little here and there. Then you want to add a motor. Then you really have to make a new body..then learn to machine...then build an entire thing from scratch...then fix it/aka build another one from scratch (new thread coming in 2 months). Good luck!

One thing maybe we could work on together is the funnel. A symmetrical cone at the bottom results in poor distribution that will channel. I know, I built one. Every HG-one owner knows as well. The Monolith grinder guy figured something out, but they're keeping secrets and aren't not open-source types. What we need is either a cone of a really small diameter opening to hit the grinds into each other and disturb them, or a pharos bottom funnel type thing that is a cone sort of tiled 45 degrees. Otherwise there is some funky particle distribution stuff going on that makes for awful channeling. I'm not sure how to make the second part without a 4-axis CNC machine. Maybe hand mold it?

Carry on, don't mean to thread hijack!

Yeah, I'm leaning toward a monolith like adaptation for these burrs. It will be no where close to as pretty though!!! LOL

The grinds that this thing puts out are beautiful though! I like my Baratza Vario, but appearance of the grinds doesn't compare, and the result in the cup is amazing. Even my off shots were good in a cappuccino.

Incidentally I did ask the Monolith creator if they cared to share more photos, but I got no response. I assume they want to keep the design in-house in case there are future market developments. All good though - even what little we have is still interesting design wise.

DanoM wrote:The burrs I received are the K10 style that doesn't have the keyway. I think that's the K10 Fresh burrs, but I'm not sure. I was concerned about mounting the center burr on a shaft so it would not turn, but a good solid friction mount worked just fine and the burrs are solid.

Unless there has been a recent change none of the K10 inner burrs have a keyway slot. It's strictly an interference fit on the shaft.

spressomon wrote:Q: I assume you machined a keyway to keep the upper/male burr indexed to the carriage bolt?

JohnB. wrote:Unless there has been a recent change none of the K10 inner burrs have a keyway slot. It's strictly an interference fit on the shaft.

This is correct.

@spressomon: Thanks. It's working quite well, and as JohnB stated there is no keyway on the K10 burrs, at least on these burrs. (I can't speak to all K10's. I've seen some photos of inner burrs with keyway and some without, but don't really know how Compak ships them.)

The inner burr can be sufficiently attached to the spindle, or carriage bolt in this case, with one nut turned to have a 30 degree or steeper bevel up against the burr. A second nut on top of that keeps everything from loosening up. This also serves to center the burr on the less than bore diameter shaft/bolt. Proper term for this fit is "interference fit" as JohnB pointed out. Works just fine, and I see no need for a keyway so far with nearly a pound run through this grinder so far since there has been no slipping.

Setup of the grinder, getting everything centered and in trim is done much the way the OE sets up the Pharos in their videos. First you want to loose fit the outer burr to the carrier, get the center burr and shaft in place and snugged down, then tighten the outer burr so that you have even contact all the way around for the center burr. (There isn't much room to play around in the "carrier" here, but it does make a difference to tighten it down with the center burr taught.)

I would have some reservations about the grind quality and consistency since they measure that in microns. Of course if your taste buds are no better than mine, you may not notice.

I'm not measuring anything in microns, but I can tell you it is far improved over what my Baratza Vario puts out. Is that good enough measurement? Maybe not, but it tells me something is right.

Also remember that this is an experiment in burr to shaft mounting using an interference fit rather than a keyway. So far I've put nearly a pound of beans through the grinder and the shaft to burr connection hasn't budged a bit.

Once all the plastic PVC pipe is tightly fitting there doesn't appear to be enough give to make a difference on the grind. I'm not gluing it together, as it's an experiment, and that doesn't help the rigidity of the design yet it works.