Hello, The reason I suspected my preinfusion was inadequate was the new M3 grinder. With my mini E and my pump running full flow, the shots were good, but the Versalab was wetting the front half of the puck first, and stayed that way thru the shot, overextracting that area. I thought it could be the fast flow, and using the mid lever position added preinfusion time - even till drops formed on the bottom of the basket.
That did not help, as even the preinfusion would show up at the front half of the basket first.
I plugged in the min E and pulled a couple of shots with good results.
I'm being careful to screed the dosed basket in four directions while filling up the hole it leaves in the center. The coffee is sprayed down in a circle with the center almost empty. Other M3 users seem to have good results distributing the grinds and tamping with the way the M3 puts it in the basket.
I even took my filled and tamped basket and rotated it 180 deg before locking it in - this produced wetting the back half of the basket first. If I WDT the grounds, or grind into something and then transfer the grounds to my basket, the problem goes away. I cannot seem to get a good shot working with the grinds as they are flung into the basket unless I rework the distribution entirely.
Ha-Ha -Jim, I know what you're thinking - throw the M3 against the wall!
Eric, thanks for the tip - I descaled my baskets yesterday - they are four years old .

One more question - Changing gicluers will affect the preinfusion time, but also affects,the thermosyphon flow too correct? My needle valve is at the output of the pump and should only affect flow rate? - Dennis

When I first got the Versalab, it was producing donut rings which I knew I'd have to work on. I took the bottom funnel & wiper off and the static wiper off to clean first time, but didn't touch any thing else.
Now it floods the front half of the basket , so that very well could be something I have screwed up.
I know my wiper is different now because it make a little noise spinning.
Question: Upon completion of grinding & removing the p/f there is always a rather large chunk of ground coffee that fall out last. It is about 3/8 to 1/2" size, and although not tightly compressed, is still one big chunk that falls into the basket. Is this normal?
It produced the chunk from day one - before I took it apart.
I will contact Versalab for advice - luckily I live 45 mi. from Versalab, so my grinder wasn't ever shipped - instead it rode home in a Lexus.
Thanks, Dennis

I've read all the threads since it's debut and re-read them over time, but that part escaped me.
I'm using their p/f holder,and more often than not the weight of my p/f handle drops a little which throw the symmetry off. It is about 1/8" lower in the front sometimes. That could contribute to the problem - maybe if I always hold up properly & level would help. Then I could twist to the left and to the right while grinding as you said.
I ground into the basket with my mini E and could rotate it by hand while grinding and then tap it down once. It didn't clump the grinds most of the time. I ended up with a basket ready to tamp and go that made good shots. - Dennis

The fluffy clump free grinds of the M3 is what always impressed me about the grinder. I was on the fence about one for some time but decided to go another route with my grinders. I did do some playing with pre and full infusion. I consider preinfusion to be filling the head-space with water and partially saturating the puck before the pump kicks in. Infusion was completely saturating the puck but no drops from the bottom of the basket before the pump kicked in. In my case I was using an old two group rotary that had no preinfusion at all, as most solenoid controlled rotary pump driven machines. On this particular machine a full infusion evened out my extractions and improved the shots. I used an adjustable delay-on-make timer so I could allow the puck to fully saturate before the pump kicked in. I believe that was around 8 seconds with my 3 bar mains pressure. On the rotary pump lever actuated machine I had no need for it since it has natural preinfusion.

Unlike your case, even if I dosed half a basket, rotated it 180, or any other amount during dosing my shots always started at the front of the basket. The infusion minimized and/or eliminated that problem. Since you are using the lever based E61 you probably dont need any kind of additional preinfusion. The fact that if you rotate your basket before you lock it in, and the over extraction portion moves from the front to side/back would definitely point the finger at either a bad distribution, of an off center tamp. As Jim points out, it sounds like you may have inadvertently modified the grinder from the way it was suppose to work, that being the fluffy donut distribution. The slightly off center portafilter could be contributing to the issue because of the light and fluffy grind of the M3 but it seams rather extreme for such a minor offense.

I get a good round donut distribution from the M3, extremely fluffy. Very nice. Aparrantly Jim also had a coffee nugget which dropped out the bottom afterwards. I guess I try to use my nugget with the other grinds in the basket. I weigh the dose before grinding now and try not to lose any coffee.
As for my machine, I turned my valve down so flow is 85 ml/10sec. That takes about 10 secs for the pump to pressure up for the preinfusion. That should work out nicely. Dennis

I've got a PID'ed silvia in the mail and I'm excited for it to get here! It's only a slight upgrade from my Gaggia, but I'm excited nonetheless. But all this preinfusion talk has got me somewhat jealous I must admit...

Has anyone experimented with a sort of manual preinfusion, along the lines of this:
-Remove portafilter
-Dose, Level, Distribute, etc
-Tamp
-*Place portafilter directly under group
-*Run pump for a few seconds, soaking the puck evenly with the spray from the shower screen
-Pump off
-Lock and Load and Brew!

I really have not had the chance to play with a machine with preinfusion, but would it be possible that this sort of method could achieve similar results?

Sincerely,
Bill