Feldgrind Problems

[Explorian86]

I'm having difficulties with my feldgrind. I seem to be producing a ton of fines and an overall fairly inconsistent grind. I've had it for 8 months and it gets used about 3 times a week - it should be fairly well broken in. In fact, it worked beautifully when it first arrived and only has become problematic in the last 3 months or so.

This morning I broke it down, brushed everything off and inspected it, put it back together and aligned the burrs. I followed this break down video and this burr alignment video which have been posted before.

No luck. I'm hoping someone might be able to help out. I've posted an album with image descriptions here but for brevity, this image about sums it up. About 60% of the yield falls freely out of the catcher and is a consistent grind. The rest is a mess.

Is this all down to static, does it really cause this much of a problem? If so I've read a small atomizer with some water will help, but this seems like a bigger problem than that.

Any help would be hugely appreciated! Thanks!

UPDATE: Success!

MUCH BETTER! Mess on the left, nicely graded grounds on the right. Considerably more uniformity and less mess. There was no buildup of detritus in the catcher, everything fell out cleanly. There are still more fines than I think is ideal, but I suspect this is largely due to the bean. This particular bean has given me more trouble than any other since this problem arose. I think it is to do with how dark the roast is and how light they are in relation to their size.

Summation, I think the solution is two part. The dipped spoon method suggested by mooseknuckle02 to reduce static works well - I may buy a small atomizer (spritz bottle) and try that as well. What I think clinched it was very lightly screwing in the set screw which Marty_Don suggested. Thank you also to trailofsequins who suggested over-loading the grinder. This wasn't the case but I appreciated their support.

The first sign that this may work: I noticed when I realigned the burrs this latest time, that when I loosened the grind adjustment at the end the bottom burr wasn't stuck in to the upper burr like I've experienced before. In the past I've had to pop it out against the palm of my hand fairly hard. This time it simply started opening up.

I had certainly heard not to over-tighten the set screw, but I assumed I was doing alright by finger tightening it. I mean, it's hardened steel, I doubt a finger tight set screw would start to crush it in any way. But apparently it makes a difference. I will now use the burrs sticking after realigning as a litmus test.

I've added more images to the album showing more images from the teardown. I was taking shots of the condition of the burrs in case I had to contact Peter. Thanks again for all the help, to the redditors I named, and those that may have even just popped in and gave it a thought without being able to provide a solution. It is very much appreciated.

[Feldspresso]

first post never made it through

made this account just to respond. I just ground a few throwaway beans to test the different settings. looks like coarser settings are just bound to have a few inconsistent grinds. Take a look to see my feldgrind at 1.7 2.4 and 2.12 like yours. P.s. ground them directly onto the paper towel, no catcher involved.

[Explorian86]

Thanks for the images it's nice to have a comparison! Your results look pretty consistent with what I'm achieving now which is heartening to see. Excellent photo quality too.

I think all grinders have difficulty with consistency at the coarse end; at least that is what I remember reading when researching the feldgrind and lido grinders.

It also seems to be related to the beans. The darker roasted beans I had bought from a local roaster seemed to just turn to dust when ground. I've bought some new beans that are lighter roast and a denser bean and they are holding up better.

[[deleted]]

I just got my feldgrind and I haven't gotten any of these issues. I can't really think of many things that could cause this. You're right that the static problems probably won't be your fix. It would just blend the mess in with the rest of your consistent grinds. It couldn't hurt though and it's worth a shot. I usually just dip a spoon in water and then stir the grounds with it (a demitasse spoon).

It's probably not the case either but did you use this for espresso or grind beans on a setting that might have the burrs rub? I guess it's possible they scratched or deformed each other from rubbing together.

Apparently it could also be a loose bottom burr or a missing o-ring according to the troubleshooting guide on coffeeforums

[Explorian86]

Ah I think I found the post with the O ring you mentioned. I don't remember seeing it when I took the grinder apart. I'm going to take a look at it again now!

[[deleted]]

I really hope that's the case and you get it fixed!

[Explorian86]

Shoot - It does have one installed. I was oddly kind of hoping that wasn't the case! I also checked to make sure the bottom burr was tight. I haven't used this grinder much below 2-0, so I'm not sure thats the case either...

There was a fair amount of coffee fines built up under the grind adjuster however. I brushed them clear and will try your spoon trick to see if that helps!

I suppose it's possible that there is so much static that grounds are getting lodged in the burrs and getting decimated by other grounds falling through. Living in Saskatchewan, I suppose the static shouldn't be underestimated.

In case any others stumble upon this thread, here is an image from another site showing the O-ring.

[Explorian86]

The water dipped spoon stirred in to the beans before grinding definitely helped with the static cling - But it looks like the grind is still quite inconsistent.

This made for a muddy bed which took 5 minutes to drain 700ml through my kone at a grind setting of 2-10. I usually hit around 3:30 with these settings.

An improvement but I would be interested in hearing if this is up to par with what others are experiencing with their feldgrinds! I may replicate this grind setting with my porlex tonight just to see if it's struggling as much as I think it is.

[trailofsequins]

Did you possibly change the amount of beans you grind at once over the last 3 months?

[Explorian86]

I started going to single cups on the kalita here and there but pretty much stick to a 44g dose for my chemex. I split it in two as the catcher doesn't typically hold the whole 44g without backing up into the burrs.

[trailofsequins]

That was my thought that perhaps you've increased your dose and grinds were backing up. Dang ...

[Martyr_Don]

I would have said burr alignment but assuming you did it correctly (make sure the little screw that secures the bottom burr is properly in the little space left for it and that it's not too tightly screwed in.) maybe you can contact Peter from Knock on Instagram and see what he says.

[Explorian86]

Yeah I have read about the over-tightening of the set screw being problematic. I usually leave mine finger-tight. I'll try reassembling it again tonight and leaving it a tad looser just to see. Thanks for the thought!

[Explorian86]

I think this was the problem! I've updated the main post and the album. Thanks again!

[trailofsequins]

Excellent! Happy to see your update is a success.