Hi JJ There are a few things that I would guess it could be so here are a few questions/suggestions.
What coffee are you using? My first guess would be that you are getting channeling when going to a courser grind. Check out your puck after you pull the shot and check for holes in it. Also, you have a bottomless PF so you should see the coffee jetting through it, from your description however it does not sound like you are. I have always found it easier to pull shots with fresh coffee (less than a month old that is), it seems less prone to channeling and usually tastes better :-). Perhaps try a different coffee on your next attempts Is your machine a vibration or rotary pump machine? Vibe pump machines do take slightly longer to ramp up the pressure, but you should still get to 9 bar within (i would guess) 5 seconds. How long are the shots you are pulling, how many .ml? Good luck JohnB On Fri, Apr 6, 2012 at 3:14 AM, guido <[email protected]> wrote: > hello jj, > > i am only operating a brewtus iv for a couple of months, so i'm not > exactly an expert. but since no-one else seems to be responding, here are > my thoughts. > > have you measured the pressure against a blind filter again, is it still > at 10 bar? i think you should check this first. > > have you tried to go finer in the grind again? you could just offer too > little resistance with your coffee-bed for the pressure to build up. > > all the best, > guido. > > > Hi, I am new to this group and would love to hear some comments >> regarding my problem. >> >> For starters I just recently purchased a new Brewtus IV, along with a >> Baratza Vario W grinder and Espro (calibrated) tamper. >> >> I am relatively new to the espresso world and thought that this group >> of equipment would minimize some of the variables that can have an >> adverse effect on shot extraction. The temperature of the Brewtus is >> at the factory setting 96 degrees C (approx 205 F) and I'm using a >> naked portafilter (for assessment purposes) >> >> My goal was to attempt to achieve an 2oz pull in roughly 25 seconds. >> I would use this as a baseline and then tweak from that point. >> Ultimately, taste would be my guide. >> >> On the first day of pulling shots I will admit that I didn't really >> have a plan nor did I keep track of times and volumes. Big mistake. >> I ended up getting shots that where either took too long or too quick >> to pull. The shots either looked like crude oil, 75% crema or >> something in between. Taste ranged from almost undrinkable (crude >> oil) to something that you would expect to get from one of those >> roadside coffee kiosks (you'll drink it because it's the only place in >> town). One thing I did notice that the brew gauge frequently >> indicated 4 to 5 Bar during the extraction. >> >> The next day I decided that I would chart my pulls in an attempt to >> resolve the problem. >> >> I started by adjusting the OPV by using a blindbasket on the >> portafilter. The factory setting was at 12 Bar which I have been led >> to believe is too high. I adjusted the setting to 10 Bar which now I >> believe might still be a little too high (9.5 Bar). Anyways the >> current setting seems to be better than the factory setting. >> >> My methodology was the following: I would start by setting my grinder >> at a very fine setting, pull a shot, measure volume/time and adjust if >> necessary. I ll spare you all the details (this is getting very >> longwinded I know) but will provided a summary. Basically the first >> shots (with a very fine setting) were very dark in colour and took >> approx 60 seconds. Brew pressure measured at 9 Bar. I then made the >> grind increasingly more coarse. The dose size (14 grams) would remain >> the same. My hope was that I would be able to reduce the shot time >> and maintain the brew pressure. What ended up happening was that the >> shots times did decrease to a point and brew pressure remained >> consistant. Then mysteriously brew pressures would only climb to 4 or >> 5 Bar after pre infusion. Towards the end of the shot (at the point >> where blonding has occurred and the fluid has changed to a clear >> state) the brew pressure shoots up to 9 Bar (I realize that I am >> allowing the shot to continue too long once it has reached this >> stage). >> >> I then tried pulling shots with a 16 gram dose using the same >> methods. Basically the same pattern occurred, full brew pressure with >> the finest settings although very long shot times. Once the grinds >> became more coarse, brew measure failed to reach more than 4 or 5 Bar >> and only reached 9 Bar well after the shot should have ended. The >> same pattern occurred at 18 and 20 grams. >> >> The naked portafilter suggests that tamping and ground consistency is >> OK. The fluids tend to first appear around the perimeter and then >> focus to the center. There is a 'barber pole' effect until blonding >> occurs. Sometimes is does take a few more seconds before a single >> funnel occurs but this doesn t seem to effect the shot times and >> volumes that I have been getting. >> >> I ve run out of coffee for now and probably could use a break. >> >> Any suggestions would be greatly appreciated. >> >> Thanks, >> >> JJ >> >> > -- > You received this message because you are subscribed to the Google Groups > "Brewtus" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to brewtus+unsubscribe@** > googlegroups.com <brewtus%[email protected]>. > For more options, visit this group at http://groups.google.com/** > group/brewtus?hl=en <http://groups.google.com/group/brewtus?hl=en>. > > -- You received this message because you are subscribed to the Google Groups "Brewtus" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. 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