Barley Crusher roller gap runout

[DeafSmith]

How much runout do you see on your rollers? I just got a B.C. and I measure about .005 inch (0.13 mm) difference in the gap between maximum and minimum, both measured at the center of the rollers; i.e., the gap at the maximum is .005 inch greater at that position of the crank handle than with the handle turned by 180 degrees (minimum position). Is .005 more than normal tolerance?

 

[Schnitzengiggle]

I have a BC, and get a great crush at the factory default setting. Perhaps it isn't the roller itself.

 

[DeafSmith]

I haven't used my Barley Crusher yet, so I don't know how it will work. The .005 gap variation may not matter, and the crush may be just fine. Maybe I'm worrying about nothing, but I thought I'd ask in case anyone just happened to know if that is likely to be a problem. It will probably be a month or so before I get a chance to use it.

 

[Schnitzengiggle]

I haven't used my Barley Crusher yet, so I don't know how it will work. The .005 gap variation may not matter, and the crush may be just fine. Maybe I'm worrying about nothing, but I thought I'd ask in case anyone just happened to know if that is likely to be a problem. It will probably be a month or so before I get a chance to use it.

Well, if you are an engineer, the it might be a problem, but it works fine in real world applications.

Don't worry about it, because I took mine out of the box ran about 1/2 lb of the least expensive grain I had through it, brushed the rollers off and put into use.

I have had consisten 80% brewhouse efficiencies, w/o any complaints from the BC itself. don't fudge w/the factory settings until you've crushed a few grainbills through it. I think you'll be satisfied with your first crush, I know I was, especially coming from using my LHBS mill and crush (it sucked balls!).

Check out my picture gallery it has a few pictures of my crush with the BC at its default.

When your sone with that check this out and enjoy!

DWHAHB!!!

 

[DeafSmith]

Looking good!

Oh, the grain crush looks real good, too.

Thanks!

 

[jja]

Measure at the actual observed min and max, not 180 deg position of the knob, i.e. measure several times through the adjustment range. You should be able to see the min and max pretty easily. My 1st gen BC knobs go from min to max in far less than 180 deg rotation. I know I've tried various grains at .030 up to .048.

 

[DeafSmith]

Measure at the actual observed min and max, not 180 deg position of the knob, i.e. measure several times through the adjustment range. You should be able to see the min and max pretty easily. My 1st gen BC knobs go from min to max in far less than 180 deg rotation. I know I've tried various grains at .030 up to .048.

I'm not talking about the adjustment range with the eccentric knobs, but about the variation in the gap at a single setting as the rollers are turned through one revolution of the crank handle. With the rollers set at the factory setting, as I turn the crank handle, I can measure a gap of .035 inch at one point and .030 at the point where the handle is in the opposite position. It'll probably work OK, but I just wondered if this was typical or not. I don't have any grain right now to test it - trying to put together an all-grain system, but it'll be a little while before I'm ready to try it out.

 

[jja]

I'm not talking about the adjustment range with the eccentric knobs, but about the variation in the gap at a single setting as the rollers are turned through one revolution of the crank handle..

Ahh... no, I have not seen that much variation. I typically run my spark plug guages up and down to be sure the set screw sticks, and seem to get good even gaps. You could disassemble the unit and run the rollers against a straightedge.

 

[BrewBeemer]

How much runout do you see on your rollers? I just got a B.C. and I measure about .005 inch (0.13 mm) difference in the gap between maximum and minimum, both measured at the center of the rollers; i.e., the gap at the maximum is .005 inch greater at that position of the crank handle than with the handle turned by 180 degrees (minimum position). Is .005 more than normal tolerance?

Steve; are the end journals part of the knurled roller one machined piece or they just pressed in stub journals? If two piece the journal bore may not be concentric with the roller or not dead nuts parallel with the roller.
On the Monster Mills the journals with knurled rollers they are made of a single piece of stock plus there is a center bored pilot at each end of each journal.
This for maintaining concentric machining, they spin dead nuts true between centers on the lathe. I checked my MM rollers while polishing the journals removing the rough tooling marks on the journals to a miror finish then sent out and case hardened. This for long oilite bushing and knurling life.
I would question the manufacture if this is within their spec tolerances, for me this is too far off. I would ask for a replacement mill unless this is their normal runout, hard to believe. Spin them on "V" blocks maybe the rollers can be thumped with wood and hammer to correct this eccentric problem without ending up with a wobbling journal ends when done.

 

[DeafSmith]

Steve; are the end journals part of the knurled roller one machined piece or they just pressed in stub journals? If two piece the journal bore may not be concentric with the roller or not dead nuts parallel with the roller.
On the Monster Mills the journals with knurled rollers they are made of a single piece of stock plus there is a center bored pilot at each end of each journal.
This for maintaining concentric machining, they spin dead nuts true between centers on the lathe. I checked my MM rollers while polishing the journals removing the rough tooling marks on the journals to a miror finish then sent out and case hardened. This for long oilite bushing and knurling life.
I would question the manufacture if this is within their spec tolerances, for me this is too far off. I would ask for a replacement mill unless this is their normal runout, hard to believe. Spin them on "V" blocks maybe the rollers can be thumped with wood and hammer to correct this eccentric problem without ending up with a wobbling journal ends when done.

Carl, I took off one roller (the easiest one, with the eccentrics). It has a hole in each end, with a bronze bushing pressed into the hole. The eccentrics rest in the aluminum end plates and have a stub which fits into the bushing in the roller. I assume the other roller is similar - in that one I can see bronze bushings in the aluminum end plates - not sure how the shafts are mounted to the roller since I didn't remove that one. And, of course, I'm measuring on top of the knurling - maybe the bottom is actually more critical to the crush? - and I have no way to measure that. I don't have any "V" blocks to spin them on - I'll just have to see how the crush is when I get some grain. If it's OK, then I'm satified. Not worried about lifetime of the mill, as it will see light duty - I doubt that I'll brew more than about a half dozen 5 gallon batches a year, since I'm the only one drinking it. :rockin:

 

[BrewBeemer]

At 0.005" that about equals the slop in the two seperate roller bushing alone, your not that far off like having a 0.015" variation. If the knurling is rather sharp I was thinking take a piece of brass shim stock app 0.040" x 1" to 2" wide and loop a piece of fine emery paper like 320 grit around it. Adjust until your just making contact between the rollers and first rotate the driven roller (free wheeling) first to make sure it's trued up first. Then apply the same process to true up the drive (motor powered or hand crank) roller until it's concentric. Just checking to see that both become concentric. With only 0.005" out you shouldn't knock down much of the knurling points to affect the grain pulling ability. Granted bushing slop alone can be 0.002" to 0.005" alone depending on the oilite interference fit and bushing crush. Bushing clearance should one sided with the roller repelling each other due to the grain crush pressure. This should be a one beer correction project. Cheers Steve, laptop no slide tonight. Survivor my favorite TV program is starting i'm off.