# Need some help with consistency



## RagingMammoth (Sep 21, 2013)

Well, first shot was as planned. 17g in, 28g out in 24 seconds. Perfect.

Second took 20 seconds to get 8 grams out.

Thing is, I'm using a tamping mat for pressure. Same machine and grinder (Alex Duetto, Macap M4 something) and I don't know why the shot altered so drastically. My guess is that the first shot had some of yesterdays stale grinds in it... would that have done it?

I'm going to fiddle with the grind later, I've kind of lost my temper at the moment.


----------



## Mrboots2u (May 10, 2013)

You weighed your dose on a a scale to 0.1 g ?

That a fairly big change in shot time , I'd be surprised if tamping pressure variable made that big a difference to the timings ...

Stale grinds would normally make a shot run faster .....

Distribution in the PF could have played a part

Your single dosing when you grind ?

Same pre infusion on each shot ?


----------



## The Systemic Kid (Nov 23, 2012)

Stale grinds will have dried out so would offer less resistance to the pressure of water through the puck. With the same grind, using fresh beans, your grind is too fine for 8grms out in 20 secs, so back off the grind - keep tamp pressure constant and adjust until you have 25-34grms out in 25-30secs.


----------



## RagingMammoth (Sep 21, 2013)

Mrboots2u said:


> You weighed your dose on a a scale to 0.1 g ?
> 
> That a fairly big change in shot time , I'd be surprised if tamping pressure variable made that big a difference to the timings ...
> 
> ...


Yeah, I weighed in 18g. I said that the stale grinds made my first shot faster. I single dose every time, and I didn't add any extra time to the preinfuse. Normally it takes 6 seconds though.


----------



## RagingMammoth (Sep 21, 2013)

The Systemic Kid said:


> Stale grinds will have dried out so would offer less resistance to the pressure of water through the puck. With the same grind, using fresh beans, your grind is too fine for 8grms out in 20 secs, so back off the grind - keep tamp pressure constant and adjust until you have 25-34grms out in 25-30secs.


I'm going to have another try now, I'll update you all.


----------



## Mrboots2u (May 10, 2013)

Ok either there is a massive difference in the consistency coming out the grinder from shot to shot and or same with distribution and tamping ( any channeling first shot ? )


----------



## RagingMammoth (Sep 21, 2013)

Mrboots2u said:


> Ok either there is a massive difference in the consistency coming out the grinder from shot to shot and or same with distribution and tamping ( any channeling first shot ? )


I'm not using a bottomless. I can't use my tamping mat if I use bottomless.

I tried again without altering anything, and it came out with 28g in 33 seconds. Bit over but I'll try again.


----------



## johnealey (May 19, 2014)

RagingMammoth said:


> I'm not using a bottomless. I can't use my tamping mat if I use bottomless.
> 
> .


You should be able to use your tamping mat with a bottomless, just requires a little edge of the counter jeopardy:act-up:.

Seriously though, use a 22g vst in rancillio handle every time ( am sure some of that is based more on "bought it therfore must use it" than inconcistent tamping.

John


----------



## RagingMammoth (Sep 21, 2013)

johnealey said:


> You should be able to use your tamping mat with a bottomless, just requires a little edge of the counter jeopardy:act-up:.
> 
> Seriously though, use a 22g vst in rancillio handle every time ( am sure some of that is based more on "bought it therfore must use it" than inconcistent tamping.
> 
> John


I tried it, tamp was wonky every time I tried.

Right, I dialled it down a tiny bit more. 28g in 26 seconds. Tasted great.


----------

