I’m looking to close the gap a bit on my mill but I don’t have feeler gauges. Can anyone tell me what household items may suffice to measure a certain gap? I would think a credit card would be a specific gap that would work. Thanks!
Credit card is a bit thicker than .040
Anything flat will suffice as long as you can use it to be sure the gap is even. You could fold up paper even. The number only matters if you adjust frequently and want to be able to reset easily at 0.0XX
A credit card will get you close.
This mill is set to .045", I’m looking to get closer to .040 or .035. Looks like credit cards are .030.
My bad, try a Costco card, they are thicker.
I use a 0.88mm guitar pick, which is 0.035"
I use four standard business cards. You can use two sets on either side of the mill to make sure it’s even all the way across. Works good so far.
The credit card thicknesses are changing with the roll-out of “chip & pin”. The new cards are much thicker than your old Visa/MC was.
Just something to keep in mind going forward.
Paul
My grain mill (BrewTek) has dimples on the round things that are rotated to adjust the setting and a diagram that shows what location of the dimples is what setting. While not as accurate as feeler gauges it’s worked for me.
Why not just adjust based on the crush?
Too pragmatic?
Crazy talk.
My mill is difficult to adjust. Sight turns on the knob move the gap a lot (relatively speaking). If I try to adjust by eye balling the gap I think I would waste my time loosening when I want to tighten, etc. So I use a feeler gauge to ensure the gap moves the direction I want it to go.
Guess so. People seem more worried about gaps than crush.
Of course they are because the “gap” largely dictates the “crush”, and when adjustments needs to be made you can’t dial your mill to a certain “crush level” but you can dial to a specific “gap distance” between rollers. One serves as a sort of measure for the other.
Otherwise, we’d just recommend that the OP set his mill for the “optimal crush” and he’d be all set. 
My Cereal Killer has marks. I cant remember what they say, .025 .050 .1 maybe? I run it halfway between the lowest and middlest. Crush looks like crush and I dont get stuck. I ran it at the tightest for a long time until my last batch that got stuck. Too much flour I reckon.
There are different mills. I have a 3 roll MM, the first gap is gentle to crack the grain, the and the second is where it does the more thorough milling. Then there are those that condition the malt and get more intact husks, and can mill a little tighter, and it still looks good.
How about 6 row that has a smaller grain size? Or rye, wheat berries, or golden naked oats that are smaller than barley?
The lauter screen will also have an influence on how you want the cruch to look. For my false bottom not so fine. For the round cooler with the bazooka screen I can go finer. I have a SS hose braid in the 72 quart blue cooler I can go pretty fine, maybe not at fine as Denny goes, but I wouldn’t use it on the false bottom.
Like most things, it depends.
But IMO that’s exactly what he should be doing. The gap that works for me may not work for you, so how could I recommend a setting to anyone? Besides, I have no idea what my gap is. I set it for optimal crush years ago and it’s never been changed.
IMO get a feeler gauge. if you’re roller is different then mine…2 vs. 3 for instance, you may get different results. for me, i know exactly what gap I want for barley,vs rye, vs. wheat…no guessing. they are cheap so no reason to guess and just know what gap for what grain.
EDIT: as Denny mentioned, do visual. husks intact but separated, and good mix of crushed grain and flour. for me and my system, gap of .030 for barley works great. just depends on your system.
I understand. The reason I commented about this is my last brew missed the OG by quite a bit. New grain mill and perhaps everything isn’t listed perfectly in BeerSmith, but it was enough to say perhaps I should move it from the “medium crush” setting.