Search found 116 matches

by decaf_Ed
April 22nd, 2013, 11:55 pm
Forum: Grinders
Replies: 83
Views: 18644

DIY robur belt-driven grinder

There's one degree-of-freedom (of the two or three you care about) of bearing stiffness that benefits greatly by spacing, namely the rotation you get when each of the two bearings has simultaneous radial deflection in the opposite direction. This stiffness tends to go with the square of the spacing....
by decaf_Ed
January 4th, 2013, 10:37 am
Forum: Espresso Machines
Replies: 6
Views: 2568

Vibiemme Double Domobar PID tuning

Apparently on my machine, when turned off for a short time (like one minute, +/- 300%), there's often a big temperature overshoot after turning back on. That's the only big overshoot I've seen, now that I've been looking for overshoot. I wasn't looking for any overshoot before I changed the PID valu...
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by decaf_Ed
December 5th, 2012, 6:45 pm
Forum: Espresso Machines
Replies: 6
Views: 2568

Vibiemme Double Domobar PID tuning

FYI... I got a 6-degF overshoot with D=15 (as opposed to the usual 2-degF, over and under, with the factory settings), so I dropped it down to D=5 and things seem better. I haven't seen more than a +/-1 degF variation so far. I'll try raising D again later and see if I can repeat that +6-degF behavior
by decaf_Ed
December 5th, 2012, 6:27 pm
Forum: Repairs, Restorations & Mods
Replies: 1
Views: 480

Vibiemme Double Domobar vibration noise... solved.

So did you put some thread locker on it this time? -Ed
by decaf_Ed
November 22nd, 2012, 8:40 pm
Forum: Espresso Machines
Replies: 6
Views: 564

Running Vibiemme DoubleDomo with steam boiler off

For rattle-suppression, a very small blob of silicone caulk in the right locations will do wonders. That's the 100% (real) stuff, not the water-cleanup variant. It's good for way over 200F. Clear version may be best (aesthetically) in visible areas. -Ed
by decaf_Ed
November 18th, 2012, 11:58 pm
Forum: Espresso Machines
Replies: 3
Views: 1086

Expobar Brewtus IV: PID Brew Temperature Rising Past Setpoint

I've seen that same behavior on other double-boiler machines. As JimG suggested, the steam boiler is a potential heat source for the brew boiler, but the PID circuit for the brew boiler only controls the heater for the brew boiler. There's typically no actively-controlled cooling mode available, so ...
by decaf_Ed
November 13th, 2012, 9:23 am
Forum: Espresso Machines
Replies: 9
Views: 4204

When E61 expansion valve (OPV) fails...

Randy, You did an extraordinary job on that manual. Hopefully the rest of the world takes note and follows your lead. -Ed
by decaf_Ed
February 16th, 2012, 8:50 am
Forum: Grinders
Replies: 23
Views: 19161

Large conical vs flat burrs: Consistency and pour characteristics?

Doug, Thanks for the insightful (and civil) post. -Ed
by decaf_Ed
November 28th, 2011, 11:49 am
Forum: Knockbox
Replies: 5
Views: 634

Effect of brew temperature on flow rate

That is very interesting data. How do you correlate flow rate through the puck with flow rate into the boiler, with presumably varying resistance in the puck? -Ed
by decaf_Ed
September 13th, 2011, 12:38 pm
Forum: Knockbox
Replies: 9
Views: 922

Any machinists want to build a custom part?

I totally agree on the concept... mass that isn't changing (plunger) is high, mass that is changing (beans) is low, therefore consistency. It's just the comment on having to add WDT to the prep that kinda suggests the possibility that the auger isn't totally isolating the burrs from the effective we...