How do I get rid of the "6 holes of death" from my puck

[Kuban111]

Hi all,
Can someone please help me get rid of the 6 hole imprints on my puck.

This is my situation.
Using a naked P/F with a double basket & a RB flat tamper.
My machine is set to 9 bars.

I dose and distribute using the WDT method.
I've tried dosing 16, 17 or even 18g.
I know I leave enough space between the grounds and the screw,
No imprint of the screw on the puck.
I've tried light to heavy tamp.

But I still see the hole's of death on my puck.
The holes are all ways at the same place & same distance from each other.
Not all over the puck like I've seen on some of the pics here of channeling.
I'm thinking that it's due to pressure build up coming from the screen
I could see that it's due to were the water comes out of the group head screen.
I tried brushing and cleaning the screen.
But I still get the wholes.
Just for the record some times I only get 4 or 5 holes on the puck.

The size of the holes are not like pin holes they are more like nail holes.
They are also in a circle patter.

So what am I doing wrong or what should I be doing better.
Please help, any light in how I can get rid of this problem will sure help.

Thank you,
Michael

[dsc]

Hi Michael,

You mean holes like this:



or this:



?

I get that when I put less that 18g in my double basket on my Gaggia Classic. Don't know why I get it or how to eliminate it either:)

Cheers,
dsc.

[Kuban111]

dsc,

wow thanks for the pic. Sorry don't have any myself.
the 1st pic sure has the same size holes I get.

[Kuban111]

If you can imagine 6 holes in a circular pattern.
That's what I get imprinted on my puck.

Not always all the 6 holes come out on the puck

Sometimes I get 3 or just 4 in a circular patter.
It's always in the same pattern


Thanks again to anyone that can help

[Beezer]

Maybe try dosing a bit higher? Is your puck wet and soupy when you're done pulling the shot? Do you get an imprint of the screen and screw on the puck after you're done? If not, you might be underdosing a bit, which can lead to pinhole (or in this case, nailhole) channeling. I know I get pinholes if I don't dose fairly high with my Anita.

[scottyg514]

I once found by underdosing I would get less channeling.

Maybe you can think of the water coming out of your group like anything being forced under pressure.

The futher it travels, the more the drop in velocity.

So if the puck is just about touching the group screen at the start of an extraction,the streams may shoot right through it.

But if you have a little distance between the screen & the puck, when the water hits it, it may get deflected & do whats it's suppose to do & not instantly go through the puck like a bullet.

I could be wrong, but this has worked for me.

[another_jim]

I get it on the Elektra when the dispersion block needs to be cleaned (it's just above the shower screen, and has a screw that removes it, mostly the same one as for the shower screen itself). The Elektra block has six holes in a hexagon pattern; other machines have different patterns. When these get slightly clogged with coffee oils, they can spray hard enough to indent the top of the puck. The cleaning frequency depends on how small the holes are. The Elektra's are tiny, and I need to do it every month.

[Psyd]

Hi all,
This is my situation.
Using a naked P/F with a double basket & a RB flat tamper.
My machine is set to 9 bars.

You don't tell us how old the machine is. It could be that you need to replace the dispersion screen. They aren't remarkably expensive (probably cost as much to ship as to buy the thing!) so it'd be a cheap experiment even if that's not it.

[Kuban111]

Hey guy's,

Thank you all for the very helpful input & replies.

My machine is only 1 month old, it was a floor demo model that daily grind had on sale.

It looked and smells new, I checked it out from top to bottom (my first machine).

I will try cleaning it and I believe I did get fewer holes when I under dose the basket.

I'm going to focus and experiment with under dosing the basket.


Any suggestions on amount of grams I should start at?


Thanks againg for everyones help.

[edwa]

If you've been grinding up 18 grams why not try starting at 14?

[Kuban111]

14 G on a double basket is ok?

Should I change my grind too.

[Jasonian]

14G on a double basket is "normale".

If you were getting the correct time on your pours at 18 grams, then you should probably grind a little finer for a lighter dose.

[DaveC]

Hi all,
Can someone please help me get rid of the 6 hole imprints on my puck.

The size of the holes are not like pin holes they are more like nail holes.
They are also in a circle patter.

So what am I doing wrong or what should I be doing better.
Please help, any light in how I can get rid of this problem will sure help.

Thank you,
Michael

When I reviewed that machine, I was not totally happy with the shower screen and noticed a similar problem. The brew pressure on the machine was too high, but I see you lowered it to around 9 bar (as I did). However the situation below is commonplace and difficult to remedy.

The shower-screen had a tendency to clog easily, and unless kept clean could send high pressure jets off at strange angles. Also flow from shower-screen
tended to be unneven This caused correctly tamped pucks to show evidence of channeling and cratering. Not all, but more than is reasonable (often leaving a real mess on the shower-screen). Additionally the higher pressures mentioned earlier and showerscreen design (not as free flowing as other designs), cause a high pressure shock" to the puck at beginning of pour and not such a gentle infusion (small powerful needle jets).

One of the other problems is of course if the machine is a bit too hot, which only makes matters worse, so it might be worth flushing slightly more and definitely keep that shower screen clean. I just reviewd my photo archive and I hve closups of the screen, I remember what a pig it was for clogging and how removing it for cleaning on a regular basis is advised.

Dave

[Kuban111]

Dave thanks for the info,

Do you remember what size basket you used and grams?

I did find that the machine does tend to get some what piggish like you said.
I do have to clean it up more than I thought.

I've been playing with the steam wand, leaving it open for the first seconds when I pull my shoots then closing it. I've been getting great results from this. (Pre infusion) type of technique.
http://www.home-barista.com/forum...tomatic-t3656.html

It also looks like the Venus responds well to an overdose double basket

This is my first machine so I'm open to anything & trying it all right now so I can get to know her.

Dave again thanks for the help and if you have any other suggestions, bring it on.

PS: checked you website looks really great. Also I lived in Coventry for a while, miss the brown sauce.

[DaveC]

Dave thanks for the info, Do you remember what size basket you used and grams?

PS: checked you website looks really great. Also I lived in Coventry for a while, miss the brown sauce.

Just checked my photo archive and the horribly cratered puck is in a single, I think the problem is very slightly lessened with a double. Opening the steam wand then closing it to get a slower pressure ramp up is a good idea, I never tried that. Just know that you will be intimately familiar with the other side of the shower screen

I hope by "really great" website you mean the Coffeetime forum and the Coffeetime Wiki, the website holding the review isn't mine. Just to confuse matters there is an OLD coffeetime website that isn't updated anymore, I thought that the UK/Europe coffee community was better served by a Wiki and Forum working together. The website approach to holding articles was just to difficult to maintain as the software wasn't geared up for doing it.

So
http://myweb.tiscali.co.uk/coffeetime/index.htm (is old and not updated any more, plus it's got a load of "April Fool" Products on it, that don't really exist, like the Lattegraphe and the infamous Digitamp ). I simply keep it to help the search engines find the other sites



of course if the Digitamp really existed, I think people would want to buy it!

More fun but fake/non existent products at http://myweb.tiscali.co.uk/coffeetime/_sgg/m4m1_1.htm

[psycho_supreme]

bahaha, that's a great site. I love the "latte art cup mover device" that makes latte art without moving the pitcher.

It's a little comic relief on a long day

-Matt

[Kuban111]

Just know that you will be intimately familiar with the other side of the shower screen

I can just hear my wife, more time spend with the espresso machine than me.

Davec Thanks for reminding me
You've been very helpful.