mreloc wrote:Whelp, I spent a few hours digging into alignment. I'd initially aligned the top (fixed) burr by shimming the carrier and marker test and got it pretty even, with good flavor but concerned that I could only grind acceptable espresso 3 lines off of chirp. Then after reading suggestions to align moving burr, applied a depth gauge method (it's a bitch since the needle constantly bounces and speed affects the degree of bounce when measuring from peak to peak on the edge) and it felt like there was too much room for human error. After doing my best and reassembling, I got 2 lines up on the coarseness scale, but the espresso lost clarity and just tasted blah.

Needless to say, I undid the shimming on the bottom burr and tried my best to get the top burr realinged- which got me back to where I started- 3 lines off of burr chirp for espresso but better balance in the cup.

A couple of issues with my situation: 1) The misalignment seems to only exist midway between the screws, which would mean shimming away from the screws instead of under them which I'd prefer to reduce the fulcrum effect.
2) my top burr carrier screws are getting tired of being tightened and removed by teh T-20 bit. I think I've been overtightening since the aluminum burr carrier now has indents where I tighten the three screws down to hold it to the body of the grinder. Be careful with those!

I'd like to find a local pro to do this for me. Hopefully I can find one.

I am sorry if I send you on an odyssey.
I hope you find the local pro that you are looking for.

For anyone that might be interested in the solution for these issues I would give this advice.
Only start working on machines you are comfortable to work on from experience (at least from other fields) or don't mind breaking.
Use a torque wrench for any screws that have something to do with the alignment. Not only might this save you from damaging your grinder but also it helps with consistency when adding shims as a different torque on different screws might deform any metal temporarily or permanently, e.g. after adding shims. I won't tell you which torque is right for the 807 as I don't know and don't want to get in trouble, but I have never heard of anyone using more than 4Nm on any grinder and I have only used way less than that myself. For reference somebody with medium hand strength probably won't reach 4Nm with a screwdriver, but this is not supposed to mean that you should tighten screws as hard as you can. Also 4Nm is easy to achieve with any kind of wrench even if it is really short like the ones from the Swedish furniture house.
No need to worry about the precision of a a jumping depth gauge. Just make sure that you are turning the burr in the direction so that the needle falls down the 90 degree angle instead of forcing it against it, this will allow the needle to slowly go up the slope between two teeth. Turn the burr slowly by hand or screwdriver. Only look at the highest number the hand reaches on the dial before it falls down. It takes a while to get used to the jumpy movement, but in the end it doesn't matter.
Something else to check before checking the burr is the moving burr carrier. Just remove the burr and measure the burr carrier with the depth gauge. The carrier should be running with minimal play.
Also checking both ways that you can mount the burr on the carrier for the better starting point might save you some time. For burrs with 3 screws you need to check 3 positions.
About question 1: the burr only having 2 screws is annoying. And yes bending the burr is a real concern here, but not so much when using a torque wrench.
It sounds like you have 2 low points. In any case I would recommend to only add shims at one point at once. This helps to keep the guesswork out of it and also might save you from crucial mistakes. I would recommend starting with the point where the longest area with marker left on it is.

coffeeOnTheBrain wrote: I won't tell you which torque is right for the 807 as I don't know and don't want to get in trouble, but I have never heard of anyone using more than 4Nm on any grinder and I have only used way less than that myself. For reference somebody with medium hand strength probably won't reach 4Nm with a screwdriver, but this is not supposed to mean that you should tighten screws as hard as you can. Also 4Nm is easy to achieve with any kind of wrench even if it is really short like the ones from the Swedish furniture house.

I just got a torque limiter screwdriver. It is inch-pound. ~8.8 inch-pound is a Nm. I was planning to do 10, tighten both screws, then tighten both to 18, then both two 26. You think 3Nm, ~26 inch-pound is too much, or okay? Prima Coffee said to tighten half way on a torque screwdriver. Most are 10 to 50 inch-pound rang, so half would be about 30, so a bit more than 3 Nm, but I do not know the range of their screwdriver.

Not terribly helpful information from the vendor.

Remember that torque settings for bolts (or "machine screws" in this case) are generally close to the point at which the bolt fails and depend on the lubrication. My guess, and only a guess, is that being uniform may be important and that maximizing the force the screw presses down on the burr is less important. Breaking a screw or deforming the threads in the burr carrier aren't good outcomes. So much force that you're deforming the burr probably isn't a good thing either.

https://www.trfastenings.com/knowledge- ... ng-torques

Note that "socket head" (hex or Torx) may have lower ratings as shallow heads may fail before the bolt itself does. See https://www.trfastenings.com/knowledge- ... ng-torques

So i contacted a vendor in Germany and asked about people reporting bad alignment and not being able to grind fine enough for light roast. I got this answer back:

"That the grinding discs are not properly aligned is absolute nonsense.
The so-called experts who post the mill unpack the mill and screw around.
What is true is, this grinder is not suitable for light roasted coffees. For dark coffees, this grinder is a dream."

Bue wrote:So i contacted a vendor in Germany and asked about people reporting bad alignment and not being able to grind fine enough for light roast. I got this answer back:

"That the grinding discs are not properly aligned is absolute nonsense.
The so-called experts who post the mill unpack the mill and screw around.
What is true is, this grinder is not suitable for light roasted coffees. For dark coffees, this grinder is a dream."

The level of detail of the vendors's answer speaks volumes on his expertise
I would agree that the Lab Sweets burrs are not pronouncing clarity in the same way some SSP burrs do, but that only means one should research what the Lab Sweet burrs pronounce and if that is what one is looking for.

Well put!

coffeeOnTheBrain wrote:I am sorry if I send you on an odyssey.
I hope you find the local pro that you are looking for.

Don't be-it's all good. Yesterday I went through and did marker alignment on the moving and stationary burrs and got them 90-95% swiping evenly, just using manual turning of the burr vs actuating the switch. Funny thing is that it didn't change my grind position at all (3 to 4 lines above chirp)- but flavor is good, and espresso flows pretty much without channeling. I suppose I'll just leave it alone at this point and let the burrs continue to break in over the next few months before doing anything else.

All this talk about light vs dark roasts has me thinking the lighter roasts will be trickiest to find the grind setting for requiring a finer setting. I'd always considered my beans "Medium" but have attached a couple of images for opinions on roast level to help us all calibrate.

mreloc wrote:Don't be-it's all good. Yesterday I went through and did marker alignment on the moving and stationary burrs and got them 90-95% swiping evenly, just using manual turning of the burr vs actuating the switch.]

Do you mean you just switched the burrs 180 degrees each? What is actuating the switch?